Master Radiology Notes Chest
Master Radiology Notes Chest
Master Radiology Notes Chest
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Normal Chest
Oblique views : retrocardiac area, post. costophernic angles & chest walls.
AP view : ribs are projected over different areas of lung from those of PA + post chest
wall is shown.
Appicogram: A.Apical view : Pt leans back, AP projection & tube angled 50-60
upward (projection of clavicles up).
B.Lordotic view : PA view, Pt leans back, (project clavicles,also done in
cases of middle lobe collapse.
Paired :Insp. & exp. film.
1. Demonstrates air trapping
2. Diaphragm movement.
3. Small pneumothorax.
4. Interstitial shadowing.
Penetrated film :
1. To show the hidden areas.
2. Demonstration of rib destruction.
3. Cavitation or calcification.
4. Air bronchogram demonstration.
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* Ant junctioned line: is where the lungs meet anterior to the ascending aorta. It is only 1 mm thick
(from below suprasternal notch).
* Post junctional line : is where the lungs meet posteriorly behind the esophagus. It is 2mm thick
(from
lung apex to level of knuckle).
* Thymus : both borders may be wavy (sign of Mulvey) dt costal cartilage indentation. It is sail
shaped, right border more straight male >female.
* Main fissures : (tangential x-ray beam)
1. PA : horizontal fissure runs from hilum to 6th rib in axillary lines may be slight down curve.
2. Lat : All fissures : oblique fissures commence post from D4 or D5 passing through ! hilum, !
left is steeper & finishes 5cm behind ! ant costophrenic angle.
* Accessory fissures :
1. Azygous fissure : comma shaped, base & nearly always rt sided (failed azygous v. to
migrate). Left side hemiazygous vein.
2. Superior accessory fissure : separates !apical from basal segments of lower lobes.
3. Inferior accessory fissure : separates ! medial basal from the other basal segments (from
cardio
phrenic angle).
4. Left sided horizontal fissure : separates lingula from other upper lobe segments.
Hidden areas :
1. Apices: appicogram.
2. Mediastinum and Hila: lateral film (for central lesions).
3. Diaphragms: post.& lat. basal segments of lower lobes & ! post. sulcus are partially observed.
4. Bones: AP, expiratory film & obliques - Tomography.
6. Lung fields :
Hidden areas :(apices, diaphragm, mediastinum, hilae and bones).
7. Hilum :
Shape, position, density :
-Normally the left hilum is 1/2-1cm higher than right (because left pulm.a. lies above
the left main bronchus before passing post.)
-They should be of equal density and size with concave lateral borders.
-Only the pulmonary arteries and upper lobe veins significantly contribute to hilar
Chest radiology 4
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shadows.
-The maximum diameter of normal descending branch of the right pulmonary
artery is 10-16mm in males, and 9-15mm in females.
-In erect position, the lower lobe vessels are larger than the upper lobe vessels as
the perfusion and areation of the upper zones are reduced.
-The pulmonary arteries accompanying the bronchi, while the veins :
a. Have fewer branches.
b. Less defined and larger.
c. Do not follow the bronchi.( They follow (drain via) interlobular septa)
* Upper lobe bronchus may appear as a ring shadow adjacent to upper outer hilum.
Pulmonary segments & bronchi :
Lymph nodes :
* Intrapulmn lymphatics drain to bronchopulmn node (1st group involved by spread from a periph.
tumor).
* Mediastinal Lns (may be involved by tumors above or below the diaphragm).
1. Ant. mediastinal nodes: (drain thymus & Rt heart - in region of aortic arch.).
2. Intrapulmn. nodes : along main bronchi.
3. Middle mediastinal nodes (lung, bronchi, lt ht, lower trachea & visceral pleura)
a. Bronchopulmn (hilar), drain into.
b. Carinal
c. Tracheo bronchial (Rt - adjacent to azygous , Lt - near RLN).
d. Paratracheal
4. Post mediastinal nodes : drain post diaphragm & lower oesophag. lie around lower descending
aorta & lower oesoph.
5. Parietal nodes: (ant & post behind sternum) ,drain soft tissue & parietal pleura (also intercostal
region).
8. Bronchial vessels :
-Normally not visualized on film.
-The arteries arise from ventral surface of the descending aorta at the level T5-T6.
-Enlarged bronchial arteries, appear as multiple small nodules around hilum.
Cause of enlargement :
* General (congestive cyanotic heart disease).
* Local (bronchiectasis, primary carcinoma).
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Differential Diagnosis
Krleys Lines :
1. A-lines : Thin, non branching lines radiating from the hilum (2-5cm in length,
thick deep intercommunicating lymphatics, DD: blood vessels).
Silhouette Sign :
-It permits localization of the lesion on the PA view by studying the mediastinal and
diaphragmatic outlines.
-These outlines are visualized because the adjacent alveoli are aerated.
-If air is displaced, the adjacent borders are obliterated where the lesion is located,
conversely if the border is retained and the abnormality is superimposed, the lesion
must be either anterior or posterior e.g.:
* Lesions of the middle lobe (rt) and lingula (lt) affect the right and left
cardiac border.
* Obliteration of the aortic knuckle is a feature of disease in apico-posterior
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Air bronchogram :
An important sign. The bronchus if air filled and not fluid filled becomes visible,
when air is displaced from the surrounding alveoli (parenchyma).
*Causes :
1. Consolidation (Pneumonia, infarction, collapse, Pulm hge, TB).
2. Pulmonary edema.
3. H.M.D = Hyaline membrane disease.
4. Lymphona.
5. Alveolar cell carcinoma.
6. Sarcoidosis.
7. Adult respiratory distress syndrome.
N.B:
* An air bronchogram does not occur within pleural fluid or solid tumor.
* It may be present in consolidation distal to a malignancy if the bronchus
remains patent.
Chest radiology 8
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Causes :
1. Pulmonary edema :
-Cardiac pulmn edema.
-Non cardiac (Uremia, hypoalbuminaemia, fluid overload).
2. Pneumonia :
-Localized : (pneumococcus).
-Generalized (fungi, parasites).
3. Neonatal :
-H.M.D
-Aspiration pneumonia.
4. Tumors :
-Lymphoma, leukemia.
-Alveolar cell carcinoma.
-Haematogenous metastasis (e.g. choriocarcinoma)
5. Alveolar blood :
-Pulmonary infarction, hematoma.
-Good pastures syndrome.
6. Miscellaneous :
-Radiation pneumonitis.
-Sarcoidosis.
Causes of Consolidation = Air bronchogram = alveolar shadows
:
-Consolidation pneumonia, TB
-Pulm edema.
-Infarction.
-Hge
-Alveolar cell ca.
-Lymphom
-HMD, ARDS
Interstitial
Shadowing :
-Thickening of parenchymal perivascular tissue.
Chest radiology 9
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- Sarcoidosis.
-ARDS
-Silicosis
- Histocytosis
-fibrosing
-cardiac LHF
-Asbestosis.
- Tuberous sclerosis
- Neurofibromatosis.
-Collagen
- Bronchiectasis
- Neoplasm lymphoma,
lymphangitis carcinomatosa
2. Sarcoidosis
4. Metastasis (renal, thyroid, trophoblastic).
6. Histoplasmosis
B. of high density :
1. Alveolar microlithiasis.
3. Haemosiderosis, silicosis.
2. Calcification (TB).
4. Tin or barium inhalation.
Chest radiology 10
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2-Benign tumors :
-Hamartoma (90% peripheral)
-Adenoma.
3-Granuloma :
-TB./ Sarcoidosis
-Histoplasmosis.
4-Infections ::
-Pneumonia,
-Abscess( Klebseilla, staph)
-Hydatid.
-Mycetoma : fungal ball.
NB: Nodular form of Fungus: Histoplasmosis. Coccidomycosis, Actinomycosis, Mycetoma
Chest radiology 11
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(Aspergillosis)
5-Vascular :
-Pulmonary infarction.
-Hematoma.
-AVM.
6-Collagen disease
-Rh. Arthritis.
7-Sarcoidosis.
8-Congenital :
-Sequestrated segment.
-Bronchogenic cyst.
9-Non Pulmonary :
-Skin lesion (lateral film helps to distinguish extra pulm masses:* Intrapulmonary mass has
acute angles with lung edge. *Extrapulmonary & mediastinal masses form obtuse angles.
-Bone lesion
-Pleura (encysted effusion, plaque)
-Artifacts.
Intracavitary bodies :
-Aspergillesis : mycetoma.
-Hydatid : disintegrated.
-Lung gangrene bl. clot in cavity.
-cavitary sq. cell carcinoma.
-simple lung abscess.
Cavitation :
-Radiologically : A cavity is a translucency within the lung parenchyma surrounded
by a complete wall (thick : 3mm or more)
*Sites of predilection for certain pathologies :
-TB mostly upper lung zone, infraclavicular.
- Aspiration abscess mostly right side, lower zone.
- Amoebic abscess always in the right lower zone.
- Pulmonary infarction commonly lower zones.
- Sequestrated segment left sided.
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Causes of cavitation : (P77, same reasons as solitary nodule, but cavitation occurred, +
bronchietasis, bullae
2. Lymphoma
3. Metastasis
4. Rheumatd nodules
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NB:
* Ruptured hydatid cysts have daughter cysts floating within!cavity = water lily sign.
* Other intracavitary lesions include inspissated pus, blood clot & cavernoliths.
* Blood clots occur with cavitating neoplasm, tuberculosis & primary infarcts.
* Common in primary tumors, & irregular masses.
* Uncommon in cavitating metastases & TB cavities.
* Meniscus sign is when intracavitary body is surrounded by crescent of air,
commonly described with fungus balls such as aspergilloma, ! ball moves as : pt,
change position.
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E. Pulm A : Aneurysm, P++, thrombus.
F. Chest wall : bone, breast, soft tiss., cartilage, parasites.
D. Lung :
1. Compensatory emphysema.
2. Obstructive emphysema.
3. Macloeds syndrome (the late sequalae of childhood bronchiolitis).
4. Unilateral bullae.
5. Congenital lobar emphysema.
E. Pulmonary vessels :
Pulmonary embolism of a major pulmonary artery at least lobar in size.
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Airway obstruction :
1. Partial hyperinflation.
2. Complete collapse.
3. Bronchocele.
4. Bronchiectasis.
5. Pneumonitis abscess.
Value of tomography :
1. To improve visualization of a lesion.
2. To localize & confirm an intrapulmonary lesion.
3. To evaluate hilum & proximal airways.
Chest radiology 18
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Chest Wall
Comment on :
A. Sternum :
1. Developmental abnormality (depressed "pectus excavatum" sternum in cong.H.D.:
ant. ribs are vertical & post ribs are horizontal, heart is displaced to the left &
appears enlarged with straight left border, prominent lung markings (Rt paracardiac)
misdiagnosed as consolidation).
2. Erosion (adjacent mediastianal mass anteriorly, infection).
3. Tumours (chondroma, chontrosarcoma, secondaries).
4. Fractures.
B. Clavical :
1. Absence outer end : (Cleidocranial dysostosis).
2. Erosion : Outer or medial end :
- Rheumatoid arthritis.
- Hyperparathyroidism.
- Infection.
3. Tumour (aneurysmal bone cyst, Ewing).
4. Fracture.
C. Ribs:
Superior or inferior unilateral or bilateral.
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- Poliomyelitis
- Old age.
Cervical ribs :
Fracture :
- Cough fracture (6-9) ribs at axillary line.
- Stress fracture 1st rib.
- Pathological fracture: senile osteoporosis, myleoma, cushing disease.
Selerosis :
A. Generalized (osteo-petrosis, metastasis, myelofibrosis).
B. Localized (Paget disease).
N.B: Loosers zone : areas of uncalcified osteoid tissue (osteomalacia): rib deformity creates
Chest radiology 20
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a bell shaped thorax.
Expansion :
a. Localised
- Paget.
- Fibrous dysplasia.
- Haemangioma.
- Aneurysmal cyst, chondroma.
- Eosinophillic granuloma.
b. Generalized :
- Thalassaemia (expansion more marked proximally + abnormal trabeculae)
- Hurlurs syndrome (generalized expansion sparing the proximal end).
- Rickets (widening of rib ends).
D. Thoracic spine :
Comment on:
1- Alignment, disc spaces (calcification = post-traumatic, ankyloses, ochronosis,
destruction in infective process). 2-Sclerosis (single dense vertebra (ivory)=
lymphoma, paget's and metastasis. 3-Destruction (pedicle = metastases).
4- Paraspinal lines.
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Diaphragm
Appearance ; (normal variants)
1. Scalloping (short curves of diaphragm, convex upward).
2. Muscle slips (small curved lines, concave upward).
3. Diaphragmatic hump or dromedary diaphragm (severe form may appear as double
contour in PA view N.B.: These is no diaphragmatic defect).
Eventration :
- Mainly left sided (thin, weak diaphragm).
- Left hemidiaphragm is elevated with mediastinal shift to the right, a feature rarely
seen with paralysis.
- May be associated with partial gastric volvulus.
- Reduced movement (seen under fluoroscopy) paradoxical movement or abscent.
Diaphragmatic movement :
On screen, normally the left hemidiaphragm move more than right by 3-6cm
Paradoxical movement : (Moves up with inspiration)
- Diaphragmatic paralysis.
- Subdiaphragmatic infection.
- Eventration.
Thickness of diaphragm :
- On left side between fundus gas and left lung (normal average of 8mm) normal
diaphragm 2-3 mm.
- If more than 8mm pathological (may be due to)
- Tumour of diaphragm : Lipomas - neurofibrimas, fibromas & cysts.
- Gastric tumour.
- Pleural effusion.
- Subphremic lesion.
Hernia of diaphragm :
Chest radiology 22
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Rupture of diaphragm :
- Trauma, surgical, may be idiopathic.
- Mainly on the left side herniation of stomach, colon strangulation.
DD : 1. Eventration (intact diaphragm)
2. Pneumothorax.
Subphrenic abscess :
- More on Rt side easy diagnosed.
- US & CT.
- Plain film :
1. Ipsilateral basal atelectasis & pleural effusion.
2. Elevated diaphragm with paradoxical or movement.
3. Gas beneath diaphragm dt. infection by gas forming org (Horizontal beam film).
4. Depression of liver edge or gastric fundus.
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1. Subpulmonary effusion.
2. Ruptured diaphragm.
DD : hump in PA film
appears as a shadow in Rt
cardiophrenic angle:
1. Fat pad.
2. Lipoma.
3. Pericordial cyst.
4. Morgagni hernia.
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5. Sentinel lines (bronch. pulm aspergillosis, malignancy, benign tumors ,congenital membrane.
6. Old pleural & pulm. scars (infarction, healed TB, sarcoid).
7. Curvilinear shadows : bullae, pneumatoceles.
8. Normal fissures & vessels.
9. Bronchial wall thickening.
Chest 24
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Clinically :
-6 hours after exposure fever, chills, dyspnea, cough.
-No wheezes or eosinophillia.
Radiologically :
A. During acute attack :
-May be normal.
-Mainly shows ground glass appearance with loss of definition of pulmon.vessels.
-In severe cases, extensive air space filling acinar shadowing with coalescence,
picture resemble pulmonary edema.
B. Between attacks (normal) :
-In subacute phase: reticulonodular pattern (fine lines together with small nodules
(1-3 mm).
C. With repeated attacks : pulmonary fibrosis :
Characterized by coarse lines particularly in mid and upper zones, together with
ring shadows 5-8mm causing honey comb appearance which is predominant in
upper zones (DD fibrosing alveolitis).
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B. Inorganic :
Damage to lung parenchyma and pleura:
A. Simple pneumoconiosis :
*Causes no respiratory disability.
*Multiple discrete nodular opacities (1-4mm) more condensed in upper zones
which is mainly associated with reticular pattern Reticulonodular
appearance.
B. Complicated pneumoconiosis :
*Causes respiratory disability : progressive dyspnea, Haemoptysis.
*Gives picture of progressive massive fibrosis:
a.Large irregular opacities (1-10 cm).
b.Usually bilateral, upper zonal and asymmetrical.
c. A linear strands from opacity to periphery of lung.
d. Picture of complication (emphysema, ischemic necrosis
Cavitation).
??TB- Bronchogenic carcinoma.
NB: Miners with rheumatoid disease may develop crops of nodules varying in size 110 cm know as (Caplans nodules or syndrome).
2. Silicosis :
Due to exposure to silica particles e.g. sand blasting and pottery, ceramic industries.
Radiologically :
Very similar to cool workers pneumoconiosis which mainly differentiated by eggshell calcification of enlarged hilar lymph nodes.
Simple forms : As cool workers pn. with or without hilar lymphadenopathy.
Complicated: As cool workers pn.
NB: Two important diseases may occur in association with silicosis and coal workers
pn. (TB and Bronchial carcinoma).
Chest 26
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3. Asbestosis :
The asbestos fibers, when inhaled, pass to the respiratory bronchioles and acini,
where they are engulfed by Macrophages and evoke a fibrotic response. Also, they
may penetrate visceral pleura, causing pleural reaction.
A. Pulmonary changes :
-Predominantly in lower lung zones (DD silicosis upper)
-Earliest changes are seen in costophrenic angles.
-At first the vessels have indistinct margins & are associat. with fine irregular lines.
-When fibrosis progress lines become more profuse reticular network pattern.
-With more progression give honey comb pattern, which is best seen in lateral
and oblique views
-Complications : Bronchial carcinoma, which is strongly related to cigarette
smoking.
NB: Fine irregular line Reticular network honey comb.
B. Pleural changes:
1. Pleural plaques :
-They are not seen for at least 10 years following exposure.
-They usually do not calcify until a latent period of 20 years.
-They are of variable size and have a characteristic distribution on parietal pleura.
a. Adjacent to ribs more prevalent in the axillary part of midchest and tend
to spare to upper zones and costophrenic angles.
b. Over central tendon of diaphragm which produce characteristic curvilinear
opacities on diaphragmatic pleura. Best seen in oblique views.
-CT is very sensitive for early detection.
2. Malignant Mesothelioma :
-The majority of such tumor is related to asbestos exposure and it does not arise
from pleural plaques.
-Appear as (see pleural diseases) nodular pleural thickening / hemorrhagic effusion/ central
mid diaphragm dt collapse / Rib involvement may occur.
Chest 27
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Chest 28
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-Types :
1ry: Cryptogenic.
2ry: In association to a variety of systemic conditions e.g. Rh. arthritis,
S.L.E., Ank. Spond., Ulcerative colitis.
Chest 29
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Radiological features :
1. In earliest stage :
-Lungs may look normal.
-The earliest minimal changes appear :
1. Ground glass (Haze) in bases . more easily seen in both cardiophrenic
angles (mainly unequal with more on right) which extend upward and
outward to costophrenic angles forming:
2. Generalized ground glass haziness of lungs.
2. With progression :
The pulmonary vessels lose their normal clarity and a fine reticulo nodular
pattern develops in the lower zones.
3. With more progression :
-Give (honeycomb appearance) coarse reticular pattern (at base) and ring
shadows (5-10mm).
-Best seen in post-costophrenic angle in lateral view.
-CT is very sensitive in early detection.
Chest 30
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2. Histocystosis X :
A disease of unknown etiology, usually affects multiple organs including the lungs.
Abn. proliferation of RE cells in (Bm - lung - HSM - LN).
3 varieties :
1. Eosinophillic Granuloma (mainly affect lungs).
2. Hand-Schullar Christian disease.
3. Laterer-Siwe disease.
Eosinophillic Granuloma :
Young adults (male : female = 4.1)
Pathology :
There is histocytic infiltration of the alveolar walls leading to its fibrosis
causing disorganization of the pulmonary architecture with formation of air cysts.
Radiological features :
-Wide spread, bilateral and symmetrical.
-In earliest stage normal.
-Reticulonodular pattern diffuse nodular shadowing in mid and upper zones (110mm) associated with fine lines.
-With progression give honey comb appearance.
-Spontaneous pneumothorax in 20% (dt air cysts).
-Pleural reaction and hilar lymphadenopathy (rare).
-Open lung biopsy is best method to confirm diagnosis.
III. Sarcoidosis :
Multisystemic, granulomatous disorder of unknown etiology, characterized by
presence of non caseating epithelioid cell granolumas with predilection to involve
lungs, skin, L.N., adrenal, uveal tracts, C.N.S and bone.
Incidence :
(30-50ys), more common in black races, female: male =2:1).
Diagnosis :
1. Clinical data.
2. Radiological findings.
3. Histopathology. Broncho alveolar lavage.
4. Kveim test: intradermal injection of extract of sarcoid tissue reaction = +ve.
5. Gallium 67 scanning (taken by nodes and parenchymal lesions).
Chest 31
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Radiological findings :
The radiographic abnormalities progress through 3 stages :
1. Lymphadenopathy only.
2. Lymphadenopathy + pulmonary lesions.
3. Pulmonary lesions only.
Chest 32
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Chest 33
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V. Neurofibromatosis :
The same as in Histocystosis X.
Radiological features :
1. Pleural effusion - Mostly bilateral, small, associated with pleuritic pain.
2. Segmental basal collapse : Thick horizontal band shadows at lung bases,
which occurs due to restricted diaphragmatic movement by pleurisy.
3. Pulmonary consolidation either due to (2ry infection or lupus pneumonitis).
4. Pulmonary edema : secondary to heart failure.
5. Diffuse interstitial shadowing : as in fibrosing alveolitis (rare).
6. Diminished diaphragmatic excursion: may be due to myopathy of the
diaphragmatic muscles.
Chest 34
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IV. AnkvlS:
-Unilateral or bilateral.
-Upper lobar fibrosis with upward retraction of hilae + bullae formation.
-Apical pleural thickening.
5. Eosinophillic granuloma.
6. Sarcoidosis.
7. Ankylosing spondylitis.
8. Progressive massive fibrosis.
Asbestosis
Cryptogenic
Rheumatoid.
Chest 35
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V. Polyarteritis Nodosa :
-Vasculitis of medium sized arteries.
-Kidneys most commonly affected.
Radiologically :
-Transient areas of consolidation which may appear rapidly then disappear
(Loefflers syndrome).
- Accentuation of vascular lung markings.
- Large nodules (few cm) may cavitate.
Radiologically :
-Single or multiple well defined pulmonary masses varying in size from few mm
to few cm which frequently cavitate.
-Air space shadowing, may occur mainly due to pulmonary hge.
-Pleural effusion.
-Hilar and mediastinal lymphadenopathy.
(??Loefflers $.)
Radiologically :
A. Loefflers syndrome : diagnostic vertical (short & thick) band // to chest wall
separated from pleura :
Chest 36
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Chest 37
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b. Exudate :
-Cloudy amber yellow thick and sticky fluid.
-Protein > 3 gm/dl.
-Caused by :
1. Bacterial pneumonia, pulmonary TB.
2. Pulmonary malignancy (1ry or metastatic).
3. Pulmonary infarction.
4. Subphrenic infection.
5. Pancreatitis.
c. Haemothorax:
-Caused by :
1. Frank blood in pl. sac (trauma, blood dis.)
2. Blood stained effusion (pulm, infarction, bronchial carcinoma).
d. Chylothoras :
-Milky fluid high in fatty acids and neutral fat.
-Caused by obstruction or destruction of the thoracic lymphatics. The
commonest cause is :
1. Chest-trauma.
2. Filariasis, lymphoma.
3. Malignant invasion.
Radiological appearance :
A. Free effusion (in the absence of pleural adhesions).
1. Small effusion:
-< 100 cc; can not be detected by PA and lateral films but detected by decubitus
view, U/S and CT.
-100-200 cc: Can fill the posterior costophrenic recess and appear in lateral film,
Chest 38
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Radiological appearance :
A. Costal encysted pleural effusion :
-Site : Along the chest wall (usually posterior and laterally).
Chest 39
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-R.A: Their radiological appearance depends on whether they are viewed en face,
in profile or obliquely.
-Best determined by fluoroscopy:
*Profile: well circumscribed, biconvex opacity with the peripheral border
adjacent to the chest wall and the inner border is convex and well defined.
*En-face: Radio-opacity of relatively low density.
*If air fluid level is seen it will be either due to therapeutic aspiration, or
development of bronchopleural fistula.
Chest 40
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* Subpulmn encysted effusion : same as free effusion but the fluid doesnt move into
pleural space with changing posture.
* Encysted mediastinal pleural effusion : mimic a mediastinal mass, diagnosis by
CT.
Effusion :
Free/ atypically ( lamellar, / subpulmonary).
Encysted (costal encysted, interlobar, mediastinal, subpulmonary
Chest 41
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II. PNEUMOTHORAX
Definition : Air within the pleural cavity due to defect in parietal or visceral pleura.
Etiology :
1. Spontaneous pneumothorax :
-Is the commonest type.
-In young adults cong. pleural bleb (usually in lung apex).
-Children staph. pneumonia.
-Old age Emphysema or chronic bronchitis.
-Other causes :
*Rupture of subpleural TB focus.
*Rupture of subpleural cyst in bronchial carcinoma or rupture of cavitating
metastasis.
*Conditions associated with interstitial pulmonary fibrosis, cystic fibrosis
Sarcoidosis.
2. Traumatic pneumothorax :
-Chest trauma due to : penetrating wound, closed chest trauma, fracture rib.
-Pleural or lung biopsy.
-Bronchoscopy and oesophagoscopy.
-C.V.P catheters introduction.
Radiological appearance :
A. A small pneumothorax :
-In the erect position, small pneumothorax collects at the apex and appears as a
small radiolucency in the pleural space which is devoid of lung markings. The
apex of lung retracts towards the hilum. The sharp white line of visceral pleura
will be visible.
-Expiratory films diagnostic, since on full expiration, the lung volume is at its
smallest while volume of pleural air is unchanged.
B. Large pneumothorax :
-A large radiolucency, which is devoid of lung markings.
-Lung retraction.
-Mediastinal shift toward the normal side which increase with expiration.
Chest 42
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Complications of pneumothorax :
1. Encystment pneumothorax: due to pleural adhesion.
R.A.: Ovoid, radiolucency adjacent to the chest wall.
D.D.: Subpleural cyst and bulla.
2. Pleural adhesion:
R.A:. Appears as a line shadow between the two pleural layers preventing
relaxation of the underlying lung.
Rupture of this adhesion may produce hydropneumothorax.
3. Lobar collapse or consolidation:
4. Pleural fluid collection :
-Small amount fluid level at costophrenic angle.
-Large amount hydropneumothorax horizontal air fluid level.
5. Pleural thickening :
-In chronic cases, thickening of visceral or parietal pleura may occur.
-Thickening of the visceral pleura may prevent re-expansion of the lung
which needs decortication.
* Cardiac Tamponade
NB:
1. open air in pleura communicate with atmosphere.
2. closedeg: ruptured bleb(So not open). increase pleural pr. but still -ve
3. Tension valve like tear air in not out !! increased pleural pr.
Chest 43
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Common sites :
1. End of pleural fissures.
2. Apices of the lung.
3. Whole pleura (diffuse pleural thickening).
Radiological appearance :
Bilateral apical thickening or symmetrical :
- Elderly patients.
- Uncertain etiology.
- Not due to TB.
- Ischaemia is a probable factor.
Unilateral apical thickening or asymmetrical :
- Pancost tumor.
- TB + Ank. spondylitis.
- Always of pathological significance.
Extensive pleural thickening :
- (unilateral or bilateral) Fibrothorax.
- Common with asbestosis.
Diffuse pleural thickening :
- Usually, the end result of previous thoracotomy, empyema, or haemothorax.
- This may cause reduced ventilation of the surrounding lung decrease in the
volume of that hemithorax.
- Decortication of the visceral pleura is needed.
Chest 44
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V. BRONCHOPlEURAL FISTULA
Communication between the air way and pleural space :
Causes :
1. Complication of pneumonectomy.
2. Rupture of lung abscess or empyema.
3. Carcinoma of nearby bronchus.
4. Penetrating chest trauma.
Radiological appearance :
Plain :
Picture similar to hydro or pyopneumothorax (if persists or enlarges after surgery,
BP fistula should be considered).
Contrast study :
-Injection of lipidol or hydrast into pleural space (sinography or passes into the
bronchial tree.
-Injection into bronchial tree passes to pleural space.
Chest 45
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Pleural fibroma :
Usually associated with hypertrophic osteoarthropathy joint pain and clubbing.
Radiological appearance :
Well defined lobulated mass :
- Site : Costal, diaphragmatic, mediastinal or at pleural fissures.
- Size : Small or occupy most of hemithorax.
Subpleural lipoma :
- Well defined rounded masses.
- May change their shape with respiration (fluoroscopy).
Malignant mesothelioma :
Usually due to prolonged exposure to asbestdust.
Radiological Appearance :
- Nodular pleural thickening around all or part of a lung.
- Hemorrhagic pleural effusion may be present, which may obscure ! mass.
- Mediastinum is mainly central despite of the presence of a large effusion due to
underlying collapse of the lung by:
*Ventilation restriction by the tumor.
*Bronchial ??/ stasis by tumor compression.
- Rib involvement may occur not common as in metastasis.
- Other asbestosis changes (pleural thickening, pl. calcification)
- CT is the best method for assessing the extent of malignant mesothelioma.
- Percutaneous or U/S needle biopsy is diagnostic.
Chest 46
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CHRONIC OBSTRUCTIVE
AIRWAY DISEASE
I-Bronchial asthma :
Definition : Widespread narrowing of the bronchi, which is paroxysmal and
reversible.
Pathogenesis : Hyper-reactivity of the larger air ways to a variety of stimuli
narrowing of bronchi, wheezing, dyspnea.
Types :
1. Extrinsic or atopic asthma : Associated with history of allergy eg.
Aspergillosis ( IgE).
2. Intrinsic or non atopic: Precipitated by a variety of factors as exercise,
infections.
Radiological appearance :
*In between acute attacks: Normal chest.
*During acute attacks :
1. Evidences of hyper inflation see later.
2. Prominent bronchovascular markings.
3. Hilar vessels enlargement (enlarged central pulmonary artery) with
normal pulmonary vessels distal to hilae, mainly due to reversible
pulmonary hypertension.
*Radiographic picture of associated conditions:
1. Recurrent infections especially in children, causing bronchial wall thickening
peri-bronchial cuffing. Appear *End-on ring shadows.
*Profile tubular tram-line shadows.
2. Flitting, patchy infiltrates of Aspergillosis.
*Radiographic picture of complications :
1. Manifestations of lower respiratory tract infection.
2. Lobar atalectasis: dt: obstruction of a lobar bronchus by plugs of sticky mucus
or mycelia of Aspergillus. Most common in Rt middle lobe.
3. Pneumothorax and pneumomediastinum: due to rupture of the alveoli by high
expiratory pressure.
Chest 47
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II-Chronic bronchitis :
Definition : Production of cough on most of day, during at least 3 consecutive
months for more than 2 years, without apparent cause.
(> in smokers, , Pollution)
Radiographic picture :
- 50% of patients normal chest.
- Signs of over inflation.
- An appearance which is characteristic for chronic bronchitis: Dirty chest:- Accentuated bronchovascular marking with small, ill defined opacities which
may represent small focal areas of atalectasis, fibrosis, perivascular and peribronchial edema. DD: IPF & bronchiectasis
- Bronchial wall thickening As before. Peribronchial cuffing : rounded, tram like.
*Picture of complications :
- Emphysema.
- Cor-pulmonale.
- T.B.
- Bronchogenic carcinoma.
- Pneumothorax.
Bronchography :
- Unnecessary but pathogneumonic for diagnosis of chronic bronchitis.
- Shows, evidence of hypertrophy of mucous secreting glands in larger air ways.
- Irregular wall of proximal bronchi.
- Abrupt termination of bronchial division after 5-8 generations = Prune tree.
Emphysema :
Definition : Enlargement of airways beyond (distal) to the terminal bronchioles with
dilation and destruction of their walls.
NB:- *Trachea, bronchi & bronchioles are strictly conducting airways.
*Resp. bronchioles, alveolar ducts & alveolar sacs-conducting & respiratory structures.
*Alveoli are purely respiratory function.
*Bulla : emphysematous space with diameter > 1 cm in the distended state & its walls are
made up of compressed surrounding lung or pleura.
Chest 48
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Types of emphysema :
A. Air trapping present at the respiratory bronchiole symptomatic:
1.Panacinar : Panlobular :
- Non selective process, characterized by destruction of all the lung distal to the
terminal bronchiole. ??Alpha-1-anti-trypsin deficiency.
- It may be localized or generalized.
2. Obstructive emphysema : misnomer : obstructive hyperinflation (bec. distal airway
is not necessarily destroyed).
3. Alveolar abnormality
*Polyalveolar lobe increased number of alveoli in a lobe
*Rigid alveoli with surrounding stroma.
5. Unilateral or lobar emphysema (Macleods syndrome):
- It is probably the result of a childhood viral infection causing bronchiolitis and
obliteration of the small airways, the involved distal air ways are ventilated by
collateral air drift air trapping of pan-acinar type.( hypertransradiant hemithorax
dt decrease perfusion.)
Causes of unilateral lung transradiancy :
Chest 49
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1. Technical radiographic factors.
2. Thoracic cage abnormalities.
3. Pulmonary embolism.
4. Compensatory or obstructive emphysema.
4. Senile emphysema :
- Dilatation of the alveolar ducts due to the aging process.
- Non significant.
5. Compensatory emphysema (hyperinflation):
- Hyperinflation of the unaffected or remaining lung due to collapse of a part or all
of the lung.
Chest 50
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emphysema, ARDS. (Oxygen as much as you want)
*Type II : ventilation defect (hypoxic, hypercapneic) GOAD, restrictive lung dis (differentiated
by FEV1). ( Care with oxygen therapy)
Radiological appearance :
The classical radiographic appearance of advanced emphysema consists of a triad
of findings (overinflation, vascular damage, bullae).
I. Panacinar :
1. Over inflation : manifested by low flat diaphragm
- Normally at end of deep inspiration the diaphragm is at the level of 6th-7th
anterior rib in frontal view, and 10-11 posterior rib. Best seen in lateral view.
- In emphysema, there is low position of the diaphragm below these levels at end
of inspiration, associated with flattening of the diaphragmatic dome.
- The low flat diaphragm results in an apparently small heart, elongated and
decreased cardio-thoracic ratio < 40%, & transverse ribs.
- Limited diaphragmatic movement with emphysema by fluoroscopy and
inspiratory, expiratory films, Where diaphragmatic excursion is about 5-10cm,
in emphysema it is < 3cm.
- Enlargement of retrosternal translucent zone on the lateral radiograph measured
from the back of the sternum to the anterior aspect of lower ascending aorta ..
should be 4cm or greater to be considered abnormal.
- Increased AP diameter of chest (barrel chest) due to bowing of the sternum
and increase thoracic kyphosis.
2. Vascular changes :
A. In widespread, generalized emphysema:
- The midfield and peripheral pulmonary vessels are attenuated in both size and
number, where the normal smooth gradation in size of vessels from the hilum
outwards is lost.
- The hilar vessels being larger than normal with abrupt tapering.
B. Localized emphysema :
Chest 51
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Giant bullae :
Chest 52
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1. Bullae.
2. Encysted pneumothorax.
- The bullae shows - Curvilinear margin, outer aspect of which makes an
acute angle with the chest wall.
- Has lung tissue peripherally.
3. Cyst.
4. Pneumatocele tomography may be needed.
5. Localized emphysema.
Chest 53
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1. Plain :
-Hyperlucency of the affected lung due to attenuation of vessels within it.
-Air trapping effect of the affected lung, but no over inflation as above.
2. Bronchography :
Not usually indicated, but shows a characteristic app.:
- Main and segmental bronchi are normal.
- Irregular dilatation of peripheral bronchi till, 6th order division.
- Lack of bronchial filling distal to the 6th order division (bronchiolitis obliterans)
giving pruned tree appearance.
3. Pulmonary angio:
- Not commonly used, reveals: attenuation of pulmonary vasculature of the
affected side.
4. Isotope :
- perfusion scan shows decrease flow.
- Ventilation scan air trapping
1. Obstructive emphysema.
3. Macloeds syndrome.
2. Unilateral bollus emphysema.
- Arterial :
Chest 54
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- Variable degree of overinflation of one lobe mostly the upper & middle lobes
show hyperlucency with few visible lung markings.
- The over expanded lobe leads to
1. Compresses remaining lung
2. Flattens or inverts ipsilateral lung
3. Mediastinal shift towards opposite side.
4. May herniate across the midline to opposite side.
Pink Buffer :( Pt. by major effort ventilates sufficient to maintain normal bl. Gases).
More common with pan acinar emphysema.
- Manifestation of hyperinflation.
- Peripheral vascular attenuation.
Where we call arterial deficiency pattern of emphysema
Complications of emphysema :
Chest 55
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DD of Emphysema:
1. Asthma: during acute attacks.
2. Primary pulmonary arterial hypertension .... there is no evidence of hyper
inflation.
Chest 56
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Chest 57
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COLLAPSE (ATELECTASIS)
Collapse means partial or complete loss of volume of a lung.
2. Cicatrization collapse :
The lung can not normally expand (decrease lung compliance) decrease it
volume. Occur in pulmonary fibrosis.
3. Adhesive collapse :
Normally the surface tension of the alveoli is decreased by surfactant
disturbance of such mechanism leads to alveolar collapse with patent major
airway. e.g. respiratory distress syndrome in premature.
Acute bronchial obstruction leads to absorption of gases within the alveoli by the
blood of pulmonary capillaries leads to alveolar collapse no air bronchogram.
Chest 58
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PATTERNS OF COLLAPSE
A. Entire lung collapse complete collapse:
Acute obstruction to one of the main bronchi lung collapse and causes
1. Opacification of the hemithorax.
2. Displacement of the mediastinum to the affected side.
3. Elevation of the diaphragm.
4. Rib approximation.
5. Compensatory hyperinflation of contralateral lung.
a. Hyperlucency with accentuation of its vascular marking.
b. Widening of rib spaces.
c. Herniation across mediastinum, mainly occur in the retrosternal space or in
azygo-ocsophageal recess posteriorly or across the midline.
B. Lobar collapse:
1. Right upper lobe collapse :
PA view : -The outer aspect of minor fissure moves upward with concavity inferior.
- Tracheal shift to the right.
- Loss of definition of shape of right border of superior mediastinum
(Silhouette sign),
Chest 59
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3. Lingular collapse :
Mainly involved in left upper lobe collapse :
PA view : Loss of definition of the left cardiac border.
Lat. view : Ant. displacement of lower part of oblique fissure and increased opacity anterior to it.
Chest 60
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Chest 61
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C. Multilobar collapse :
Right middle and lower lobe collapse dt to obstruction of bronchus intermedius.
PA view :
- A triangular shadow, with its apex at hilum and its base on diaphragm extending
laterally to costophrenic angle.This distinguish it from isolated lower lobe
collapse.
- Obliteration of diaphragm and right cardiac border.. DD: subpulmonary effusion
or elevated right diaphragm.
Lat view :
Radio opacity of a well defined upper border extending downward and forward
from back to front which obliterates the whole hemidiaphragm.
Chest 62
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CONSOLIDATION
Definition: Means replacement of air in one or more acini by fluid or solid
material. The smallest unit of consolidation is a single acinus which
casts a shadow approximately 7mm in diameter.
Causes of consolidation:
- The most common cause is acute inflammatory exudation associate with
pneumonia.(TB, infarction, collapse), (same as causes of alveolar and acinar shadows)
- Other causes:
- Pulmonary edema.
- Hemorrhage, aspiration.
- Alveolar carcinoma, lymphoma.
Consolidation is either : patchy, segmental, or lobar
Consolidation :
- When associated with patent air way air bronchogram is seen with to change
in volume .
- When it occurs secondary to bronchial obstruction no air bronchogram seen
and there is decrease in lung volume = consolidation collapse.
Air in alveoli is displaced by:
Fluid
Pneumonia, TB, IPF, bronciectasis
Pulmn. edema
Pulmn. hge
Pulmn infection
Soft tissue
Alveolar cell carcinoma
lymphoma
Chest 63
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OBSTRUCTIVE PNEUMONITIS
Pneumonic consolidation distal to an obstructive lesion :
The presence of underlying airway obstruction with consolid. can be suspected from :
1. Segmental or lobar distribution.
2. Atalectasis : Marked volume loss, which does not occur with simple
pneumonia. Tomography and bronchoscopy can exclude br.
obstruction.
3. Drowned lung: When fluid and exudate fill the lung distal to an obstruction
appears as dense homogenous consolidation with absent air
bronchogram.
4. Slow resolution : Generally if pneumonic consolidation persists more than > 8
weeks after appropriate therapy in a patient who does not
have any systemic disease suspect underlying obstruction
5. Recurrence : Repeated pneumonia to same segment or lobe is highly
suggestive of obstructing bronch. lesion, or local parenchymal
abnormality as bronchiectasis.
OBSTRUCTIVE HYPERINFLATION
See emphysema
Radiological features :
- Oval or finger like branding homogenous opacities along the axis of bronchial
tree usually upper lobe.
- Tomography (this low density is clearly seen)>
- Bronchography shows obstruction as sharp cut off in the contrast column.
- With increasing distension, bronchocele assumes a round shape DD from
bronchogenic cyst.
- Infection bronchiectatic changes.
DD: Arteriovenous malformation by:
*Multiplicity in AVM with presence of feeding and draining vessels.
*Absence of obstructive hyperinflation in AVM.
Chest 64
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BRONCHIECTASIS
Irreversible dilatation of a bronchus (persistant dilataion of ! bronchi ass. with suppurative
infla.
Etiology :
Commonly due to a severe, recurrent or persistent infection which leads to
dilation of large airways and obstruction with destructive process of smaller ones
bronchiolitis obliterans.
NB: Inflammation & destruction: large bronchi dilated (yield under pr.)
* Small obstructed (bronchiolitis obliterans).
Site :
- May be localized, multifocal or generalized.
- It is commonly basal but it may be confined to upper zone e.g. TB.
Chest 65
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3. Fusiform bronchiectasis :
- Varicose bronchiectasis with preserved side branches.
- This appearance, typically at segmental or subsegmental level is highly
suggestive of allergic aspergillosis.
Radiological features :
1. It may be normal in 7%
2. Peribronchial thickening and retained secretions.
3. Cystic spaces = air fluid levels.
4. Crowded vessels i.e loss of volume.
5. Coarse honeycomb pattern in very severe disease.
Chest 66
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PULMONARY NEOPLASM
Benign : Intrabronchial tumors (adenoma), pulmonary tumors (hamartoma, angioma)
Malignant : Bronchial, carcinoma., others, metastasis, malig, lymphoma, (carcinoid,
cylindroma).
3. Undifferentiated carcinoma.
- Small cells (Oat cell type) 20%. (APUD, never cavitates, small , massive hilar LN)
- Large cell type 10%. ( periph. or central.)
Types :
- Central: tumor arising at bronchus - early complain 66%
- Peripheral: tumor arise from lung tissue late complain 33%
Chest 67
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Radiological features :
A. Peripheral tumors: A mass in lung having the following features :
1. Shape : Mainly spherical, may be oval or dumbbell shaped.
2. Border (edge):
- Lobulated, notched (umblicated) or irregular ill-defined.
- Corona radiata: Numerous fine strands may be seen radiating into lung from
mass with more transradiant lung parenchyma than normal between these
strands which is highly suggestive for carcinoma.
3. Size : variability is unusual to identify a nodule, until it is 1cm in size or more.
4. Calcification : Lack of calcification is the basis and when it is present it is mainly
due to engulfment of the tumor to pre-existing calcified granulomata (TB,
fungal)
5. Cavitation : (better seen by CT or tomography).
- The peripheral lung mass may cavitate, revealing central air lucency.
- An air fluid level (when communicates with air way).
*The cavity : a. Frequently eccentric.
b. Thick, irregular wall, rarely smooth.
c. Tumor nodules may be visible, which may break off and lie within
the cavity simulating to a mycetoma.
*NB:-Squamous cell carcinoma cavitates more frequently than the other types while
Oat cell carcinoma never cavitates. -DD : from other cavitary lung lesions.
6. Mass effect:
- Bronchocele, due to obstruction to the segmental or subsegmental bronchus.
- Appear as peripheral tubular density which may branch &occur distal to the
mass.
7. A peripheral line shadow (Tail):
- May be seen between a peripherally located mass lesion and pleura.
Chest 68
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Chest 69
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C. Spread of tumor :
1. Hilar and mediastinal lymph node metastasis :
- May be present at the time of initial diagnosis particularly with adenocarcinoma
and Oat cell carcinoma.
- Central adenopathy may be difficult to be recognized by plain film and can be
only recognized by CT or tomography.
- CT is the most sensitive method for detecting mediastinal adenopathy.
- The size of ! L.N. detected is of great importance in suggestion of metastasis.
* < 1 cm in diameter much suggestive to normal.
* 1-2 cm in diameter considered abnormal but not necessarily neoplastic.
* > 2cm more suggestive of metastatic neoplasm.
2. Mediastinal invasion :
- Can not be evident on plain film, unless phrenic nerve is invaded.
- CT can provide evidence of mediastinal invasion.
- Phrenic nerve paralysis high hemidiaphragm on chest X-ray.
*Cause of high hemidiaphragm in Br. carc.
- Phrenic nerve paralysis.
- Lower lobe collapse.
- Subpulmonary effusion.
- Liver enlargement (2ry to metastasis).
Chest 70
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5.Blood metastasis : To :
- Suprarenal gland (common) or by lymph spread.
- Ipsilateral lung, ribs and spine.
6. Lymphangitis carcinomatosa.
7. Pulmonary osteoarthropathy.
Chest 71
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It is a subtype of adenocarcinoma.:
C/P : Cough with production of mucoid sputum (mucus is produced by malignant
cells.
DD:
1. Pulmonary edema.
2. Widespread broncho pneumonia.
Chest 72
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*Summary
- Central mass + collapse + pneumonia DD LN
- Peripheral size, shape, edge, cavitation, calcification, bronchocele, tail
- Spread: Hilum, medist, chest wall, pleura, blood, lymphangitis + Pulmn osteoarthropathy.
- Alveolar cell (local, diffuse).
- Metastotic lung
- Lymphoma
NB: Increased size of the hilum:
1. Collapse
2. Vascular eg increase Pulmon. or aortic root
3. Lymph node: Met, TB, Lymphoma.
4. Central bronchogenic.
Chest radiology 73
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METASTATIC TUMOURS
A. Pulmonary metastasis :
- Are due to haematogenous spread from breast, GIT, kidney, tests and from a
variety of bone and soft tissue sarcomas.
- Appear as, one or more discrete pulmonary nodules, which are usually spherical
and well defined but it may take any shape and may be irregular.
- A solitary metastasis may be a presenting feature without a known primary tumor.
- Solitary large cannon ball metastasis usually with renal cell carcinoma (hyper
nephroma).
- Cavitation may be seen particularly in metastasis, composed of squamous cell
carcinoma risk of pneumothorax.
- Calcification (rare) except in osteosarcoma and chondrosarcoma.
- Rate of growth is variable: Very rapid: osteosarcoma, slow: thyroid malignancy. .
Chest radiology 74
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Lymphangitis carcinomatosis:
-
Miliary Metastases.
Lymphatic permeation.
Interstitial fibrosis.
DD : Pulmonary edema.
Military metastasis :
- Miliary pattern with no evidence of lung masses or associated lymphatic obstr.
- The commonest causes are : (Thyroid, renal, trophoblastic carcinomas).
Pulmonary hypertension :
- Tumor emboli may block small pulmonary arterioles.
- Picture of pulmonary hypertension.
- It is a particular feature of choriocarcinoma.
Chest radiology 75
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MALIGNANT LYMPHOMA
Primary pulmonary involvement by malignant lymphoma is usually accompanied by
mediastinal adenopathy. (Extension from hilar LN to lung by interlobular, perivascular &
peribronchial lymphatic channels deposits in intrapulmn. small node).
Radiological features:
1. Consolidation : resembling pneumonia.
- May be segmental or lobar in shape.
- It may radiate from hilum without confining to a segmental anatomy resembling
pulmonary edema.(mixture of linear streaks, bands and clusters of small nodules).
- Air bronchogram may be seen.
- Rapid increase in size of lymphomatous deposits mainly occurs with histocytic
lymphoma.
2. Pulmonary masses :
- Usually multiple with irregular smooth border + cavitation.
- May occur subpleural.
- Mainly occurs with lymphocytic lymphoma.
3. Diffuse lymphangitic form : (Kerleys A and B lines)
- Common with histocytic lymphoma.
4. Miliary nodulation :
- May occur and indistinguishable from infection.
5. Associated features :
a. Lobar atalectasis : results from occlusion by endobronchial dis.
b. Pleural effusion.
6. Rib deposits: . Bone.
7. Pericardial effusion.
8. Radiation pneumonitis. + mediastinal adenopathy.
PDF to develop malig lymphoma :
1. Wiskott Aldrich Synd (cong immune deficiency).
2. Ataxia (telengectasia).
5. Organ transplantation.
6. Phenytoin.
Chest radiology 76
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Non-Hodgkin: * rarely starts in thorax.
* Common pulm. lesions without hilar lymphadenopathy.
Extranodal mucosa associated lymphoma ;
1. Sjogern synd, pseudolymphoma.
2. Lymphocytic interstitial pneumonia.
Leukemia :
- Microscopic infiltration of leuk cells around bronch & vessels & alvealor will.
- Mediastinal & hilar LN.
- Infection, infarction, pulmn. hge.
1. Carcinoid tumors :
- Arise from APUD system (argentaffin cells).
- Central (bronchial obstruction Extrabronchial mass).
Radiologically :
A. Peripheral lesion (10%).
- Presented as, solitary, spherical or lobular nodule, with well defined smooth
edge. Average diameter 4cm and almost never calcify.
B. Central lesion (90%):
- The tumor arising from larger bronchi often have a larger mass lying outside the
bronchus than inside it, where this extrabronchial component may be visible as
a hilar mass.
- The endobronchial part, usually seen by tomography as, spherical or lobulated
endobronchial mass and unlike br. carcinoma, the adjacent bronchial wall is
smooth and there is no bronchial narrowing above the lesion.
- Diagnosis is confirmed by bronchoscopy.
Chest radiology 77
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BENIGN TUMOURS
A. Intrabronchial tumors :
1. Adenoma :- True adenomas are rare.
- This type does not include carcinoid or cylindroma.
- It is either (mucous gland adenoma, or mucoepidermoids).
2. Papilloma : Warty tumors, frequently multiple (papillomatosis).
3. Chondroma : Arise from bronchial cartilage.
4. Fibroma and lipoma :
B. Pulmonary tumors :
1. Hamartomas : It is composed of a mixture of tissues normally present in the lung,
including (cartilage and epithelial elements).
Radiographic features :
Chest radiology 78
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2. Angioma :
a. Capillary haemangiomas.
b. Cavernous haemangiomas.
c. AV malformation.
- Often reveals multiple lesions.
- Spontaneous rupture (pulmonary haematoma).
- Draining vein + feeding artery.
3. Neurofibroma.
2. Inflammatory:
1. Granuloma: TB, Histoplasmosis.
2. Chronic abscess.
3. Parasitic (Hydatid cyst), fungball.
3. Vascular :
1. Pulmonary haematoma.
2. Pulmonary infarction.
3. AVM.
4. Others :
1. Bronchogenic cyst.
2. Mycetoma (fungal ball).
3. Sequestrated lobe.
4. Rheumatoid
5. Outside :
Psendopulmonary mass (cutaneous mass, bony lesion, pleural encysted effusion,
tumor plaque).
Chest radiology 79
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A. Infective (Abscess)
- Staph. aureus and klebsiella.
- TB.
- Aspergillosis, Hydatid, amoebic.
B. Neoplastic :
- Bronchogenic carcinoma. (squamous)
- Metastasis.
- Lymphoma.
C. Vascular :
Infarction due to :
- 1ry infection (septic emboli) = pyemia.
- 2ry infection (of a non septic infarction).
E. Granuloma ;
1. Sarcoidosis.
2. Rheumatic nodule.
3. Progressive massive fibrosis.(Pneumoconiosis)
F. Traumatic :
1. Haematoma.
MEDIASTINUM
Is situated between the lungs in the center of the thorax.
Boundaries :
Superiorly : Thoracic inlet.
Inferiorly: Central tendon of the diaphragm.
Anteriorly : Sternum.
Posteriorly : Thoracic spine.
Laterally: Parietal pleura.
Chest radiology 80
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Region I:
1. Retrosternal goiter.
2. Thymic tumors.
3. Aneurysm of ascending aorta.
4. Tortuous innominate artery.
5. Lymphangioma.
Region II:
1. Teratodermoid tumors (germinal cell neoplasms)./young adult-doesnt displace trach.
2. Thymic tumors.
3. Sternal tumors (2ries, primary chondrosarcoma, myeloma, lymphoma, giant
cell tumors)
Region III :
1. Fat deposition and pericardiac pad of fat.
2. Morgagni hernia.
3. Pleuropericardial cysts.
4. Diaphragmatic hump.
5. Lipoma.
Chest radiology 81
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THYROID TUMORS
Less than < 5% of enlarged thyroid glands in the neck extend into the mediastinum to
produce a retrosternal goiter.
Clinically :
- Soft tissue swelling that moves on swallowing.
- Dysphagia, stridor and superior vena cava compression syndrome in malignancy.
Radiographic features :
Plain :
- An oval soft tissue mass in the superior part of the anterior mediastinum, which
extends downward from the neck.
- The outline is well defined in the mediastinum but fades off in the neck due to its
anterior location.
- The mass commonly projects to the right side of mediastinum with displacement
and compression of the trachea to the left.
- In 20%, the goiters are retrotracheal posterior displacement of the esophagus
and the trachea.
- The mass may contain central nodular, linear or crescentic patterns of
calcification (not a sure sign).
CT: confirms the diagnosis :
Isotope scanning :
Shows an area of increased activity extending below ! sternal notch (diagnostic).
US: (Cystic / Solid)
Biopsy.
Chest radiology 82
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THYMIC TUMOURS
The normal thymus gland is the commonest cause of a mediastinal abnormality
in infants. It produces a triangular soft tissue mass which projects to one side often the
right of the anterior mediastinum sail sign.( More prominent in expiratory or slightly
rotated film./ Absence in DGeorges synd : T lymphocyte immune deficiency disease). It may
disappear radiologically in the presence of severe neonatal pulmonary infection.
Presentation :
- Anterior mediastinal mass in non symptomatic adult patient.
- Myasthenia gravis in 10% of cases.
Radiographic features :
Plain :
- A round or oval soft tissue mass, projects to one side of the anterior mediastinum.
- It may contain a peripheral rim or central nodules of calcification.
- Thymolipoma : a very large soft tissue mass with less radiographic density which
changes its shape with respiration.
- Malignant thymoma pleural metastasis.
CT :
1. Shows a soft tissue mass in the anterior mediastinum which occasionally
contains calcium or cyst fluid.
2. Demonstrates the signs of invasion in malignant thymomas.
3. CT guided biopsy can confirm the diagnosis.
Lateral tomography :
Can show the outline of such a mass.
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TERATODERMOID TUMOURS
Germ cell tumors include :
- Dermoid cyst (ectoderm).
- Benign or malignant teratoma (ecto, meso, endo)
- Choriocarcinoma.
- Embryonal cell carcinomas
- Seminomas.
Origin :
- All are thought to arise from primitive germ cell rests in the urogenital ridge.
- About 70% of teratodermoid tumors are benign.
Presentation :
- Anterior mediastinal mass in an asymptomatic young adult patient.
- Dyspnea, cough and chest pain.
Radiographic features :
Plain :
A. Benign dermoid cyst :
- Appears as round or oval soft tissue mass, usually project to one side of anterior
mediastinum.
- The outline is well defined but becomes irregular in very large tumors due to
peripheral atalectasis in surrounding compressed lung.
- The mass may contain a peripheral rim or central nodules of calcification, a fat
fluid level or a rudimentary tooth which is a diagnostic sign.
B. Malignant teratoma :
- Appears as a lobulated soft tissue mass which projects on both sides of the
anterior mediastinum.
Computed tomography :
Solid mass of variable attenuation densities which contains soft tissue, cyst fluid,
calcium, bone or fat.
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Radiographic features :
1. Plain :
- Appears as an oval soft tissue mass in the superior part of the anterior
mediastinum which extends up into the neck.
- It can alter in shape on respiration, but does not displace the trachea.(DD: goitre)
2. CT confirms the diagnosis :
- Cystic swelling.
- Fluid density.
FAT DEPOSITION
- Excessive deposition of fat in the mediastinum usually presents with widening of the
superior part of mediastinum and large epicardial pad of fat in asymptomatic obese
patient + Cushing.
- Diagnosis is confirmed by CT :
- DD :
1. Mediastinal lymphadenopathy.
2. Dissecting aortic aneurysm.
PLEUROPERICARDIAL CYST
Presentation : An anterior or middle mediastinal mass in asymptomatic adult patient.
Radiological features :
1. Plain :
- A round, oval or triangular soft tissue mass in the anterior or middle mediastinum
which alters its shape on respiration.
- About 75% of pleuropericardial cysts occur in right anterior cardiophrenic angle.
2. CT :
- Thin walled cyst containing fluid of low attenuation (0-10 H.U.) = Spring water
cysts.
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3. Pleuropericardial cyst.
2. Lymphangioma.
4. Lipoma.
MORGAGNI HERNIA
Anatomy :
- The foramen of morgagni is a persistent developmental defect in the diaphragm
anteriorly between the septum transversum and the costal origin of the
diaphragm.
Presentation :
- An anterior mediastinal mass in an asymptomatic adult patient.
- The hernia can produce retrosternal chest pain, epigastric pain and dyspnea.
- More than 90% of morg. hernias are situated in the right anterior cardiophrenic
angle due to the protective affect of the pericardium on the left.
Small hernias :
- Contains omentum, which appears as a rounded soft tissue mass.
Large hernias :
- Contain small or large bowel or stomach.
- Appear as soft tissue mass containing either gas or gas fluid levels.
- Barium studies (meal, follow through and enema) confirm the diagnosis e.g. a
loop of transverse colon above the diaphragm and within the chest.
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Radiological features :
- Plain chest normal.
- Abdomen nephrocalinosis or renal calculi.
- Skeletal changes of hyperparathyroidism.
The diagnosis is confirmed by isotope scan.
LIPOMA
Plain : A round or oval soft tissue mass with radiographic density and can alter in
shape on respiration.
CT : Solid mass of fatty attenuation (-50 to - 100 H.U.)
Causes :
1. Metastatic deposits 4. Sarcoidosis
7.Histoplasmosis + coccidioidomycosis
2. Lymphoma
5. Tuberculosis.
3. Leukemia.
6. Other infections and granulomas silicosis + amyloidosis
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Metastatic diseases :
- Intrathoracic (bronchial carc., cancer oesoph).
- Extrathoracic (breast, renal, adrenal, testicular, pharyngeal, laryngeal, thyroid).
Bronchial carcinoma :
- Is the commonest primary tumor to metastasize in mediastinal LN.
- It produces either:
* Unilateral hilar mass with an irregular lobulated outline.
* Widening of superior part of middle mediastinum due to a superior vena caval
compression syndrome.
Esophageal carcinoma :
- May involve the posterior mediastinal lymph nodes.
Lymphoma :
- Usually involves the paratracheal and tracheobronchial lymph nodes producing
asymmetrical bilateral widening of the superior part of the middle mediastinum.
- Involvement of subcarinal lymph nodes splaying of the carina.
- Peripheral calcification occasionally occurs in the lymph nodes egg shell
calcification.
Primary TB :
- Produces an area of consolidation in one of the lobes and a unilateral hilar
enlargement.
- Calcification may develop in both primary Ghons focus and mediastinal lymph
nodes as healing occurs.
Fungal infections :
- Such as Histoplasmosis and coccidioidomycosis.
- May produce enlargement of the hilar or paratracheal lymph nodes.
- Calcification may occur in healing stage.
- Actinomycosis is ! only fungus causing unilateral hilar lymphadenopathy : USA.
??Also :Infections mononucleosis.
Adenoviruses.
Pyogenic lung.
Mycoplasma
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Radiological features :
Plain :
a. Widening of the mediastinum.
b. A round or oval soft tissue mass in any part of mediastinum with a well defined
outline.
c. Sometimes a peripheral rim of calcification.
d. May also involve adjacent bones producing :
1. Pressure erosion of the sternum.
2. Anterior scalloping of one or two vertebral bodies.
Fluoroscopy :
- Pulsatile masses are not a sure sign, because any mass adjacent to aorta transmits
its pulsation.
Thoracic aortography (& DSA, MRI )
- Confirm the diagnosis except if the aneurysm is thrombosed.
Computed tomography :
- Shows a dilated aorta containing a central lumen of blood of high attenuation
(80-100 H.U.) due to enhancement of the blood pool with water soluble contrast
medium (true).
- A peripheral layer of clot of lower attenuation which may contain calcification
(false lumen). The subintimal flap and false lumen of a dissecting aneurysm can
be demonstrated by CT.
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BRONCHOGENIC CYST
Age : Children, Young adults.
C/O : Asymptomatic, stridor in children, cough, dyspnea, chest pain.
The majority of bronchogenic cysts occur around the carina, paratracheal,
Tracheobronchial (hilar), subcarinal regions.
Radiological Features:
Plain :
- A round or oval soft tissue mass in the middle mediastinum frequently on the
right side near ! carina.
- Rapid increase in its size indicates internal hemorrhage.
- An air fluid level is present after rupture of an infected cyst into the bronchial
tree.
CT :
- A mass of soft tissue attenuation (10-15 H.U.)
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NEUROGENIC TUMORS
Adult : (Neurofibroma, neurilemmoma Schwannoma) arise from peripheral inter
costal nerves. (paravertebral gutter)
Child : (Ganglioneuroma, Neuroblastoma) arise in the thoracic sympathetic ganglia.
Others : (Neurofibrosarcoma, Pheochromocytoma).
Occurs in the paraganglionic nerve tissue.
N.B. About 30% of neurogenic tumors are malignant.
Presentation :
- Posterior mediastinal mass in asymptomatic child or young adult.
- Back pain.
- It may extend through an intervertebral foramen into the spinal canal (hence their
name dumbbell tumors) spinal canal compression syndrome.
Radiological features :
1. Plain x-ray :
Neurofibroma :
- Neurogenic tumor appears as a round or oval soft tissue mass with well defined
outline in the paravertebral gutter which project to one side of posterior
mediastinum.
- Enlargement of the intervertebral foramen = dumbbell shaped tumor.
- May be part of multiple neurofibromatosis = Von Reklenhousen disease.
Ganglioneuroma :
- A rather elongated soft tissue mass in comparison to the more circular shape of
Neurofibroma.
Neuroblastoma :
- May contain central spicules or a peripheral rim of calcification.
NB: Neurogenic tumors may involve the posterior ribs or adjacent thoracic vertebra.
The benign N. tumors can produce :
- Splaying of several posterior ribs.
- Rib notching.
- A localized pressure erosion defect of one or two vertebral bodies.
The malignant N. tumors can produce :
- Bony destruction.
- Rapid increase in size of the mass.
- Pleural effusion .
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2. Computed tomography :
- A solid mass of soft tissue attenuation, which may contain calcification and may
involve the adjacent bones.
3. Myelography :
- Can demonstrate intraspinal extension.
NB: MRI is superior > CT (better soft T contrast).
PARAVERTEBRAL LESIONS
Common causes of paravertebral mass :
1. Neurogenic tumors.
2. A traumatic wedge compression fracture of a vertebral body with heamatoma
formation.
3. A pyogenic or tuberculous paraspinal abscess.
4. Multiple myelomas.
5. Disseminated lymphoma and metastatic carcinoma with paraspinal extension.
6. Extramedullary haemopoietic tissue.
Radiological features :
- An elougated or lobulated soft tissue shadow with a well defined outline, usually
projects on both sides of the posterior mediastinum.
- Involvement of adjacent thoracic vertebrae or intervertebral disc spaces.
DD :
1. Inflammatory lesion (narrow disc space, bone destruction).
2. Neoplastic lesion (only bone destruction).
2. Lateral film.
4. CT + CT guided biopsy.
HIATUS HERNIA
Presentation :
- Posterior mediastinal mass in asymptomatic elderly patient.
- Dyspnea, retrosternal chest pain and epigastric discomfort.
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Radiological features :
1. Plain :
- A round soft tissue mass containing an air fluid level directed behind ! heart.
- In 70% it lies to the left of midline in the posterior mediastinum.
2. Barium meal :
- Shows the stomach above the diaphragm and within chest.
OESOPHAGEAL LESIONS
1. Pharyngoesophageal pouch (Zenkers diverticulum)
Plain :
- Round soft tissue mass in sup part of post mediastinum containing air fluid level.
- Forward displacement of trachea.
2. Cancer esophagus :
3. Mega esophagus :
1. Achalasia of the cardia.
2. Benign esophageal stricture.
3. Cancer esophagus.
4. Presby esophagus.
5. Systemic sclerosis.
Radiological features :
*Plain :
- Widening of the posterior mediastinum behind ! heart on the right extending
from the thoracic inlet to the diaphragm.
- An air fluid level in the superior part of the posterior mediastinum with non
homogenous mottled appearance of food particles mixed with air.
- No air in the fundus of stomach.
*Barium swallow :
Confirms the diagnosis.
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BOCHDALEK HERNIA
Anatomy :
The foramen of Bochdalek is a persistent developmental defect in the
diaphragm posteriorly produced by a failure of the pleuro-peritoneal canal membrane
to fuse with the dorsal esophageal mesentery medially and the body wall laterally.
Presentation :
- Posterior mediastinal mass in asymptomatic adult patient.
- Acute respiratory distress in neonatal period.
Radiological features :
- About 90% of Bochdalek hernia occur in the left hemidiaphragm due to !
protective effect of liver on ! right .
1. Plain :
- Small hernia: usually contain retroperitoneal fat, kidney or spleen.
appears as a soft tissue mass posterior costophrenic angle.
- Large hernia:
* contains small or large bowel
* appears as multiple ring shadows in the chest due to air filled loops of
bowel.
* Displacement of the ! heart and mediastinum to the contralateral side.
* Ipsilateral lung is invariably hypoplastic.
2. Barium:
3. U/S
4. I.V. Urography :
Can also confirm diagnosis by showing liver, spleen or kidney above diaphragm.
NEUROENTERIC CYSTS
Etiology :
- Partial or complete persistence of neuroenteric canal + vert anomalies.
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Presentation :
- Respiratory distress or feeding difficulties in infants.
- Chest pain in young adult, if peptic ulceration occurs within it.
Radiological features :
1. Plain :
- A round or oval soft tissue mass in the posterior mediastinum between the
esophagus and the spine causing forward displacement of the esophagus.
- An air fluid level is present after rupture of an infected cyst in ! esophagus.
2. Computed tomography :
- A mass of soft tissue attenuation.
Radiological features :
1. Plain :
- A round or oval soft tissue mass behind ! heart.
- Left basal pleural effusion or atalectasis.
2. Computed tomography :
- Thin walled cystic mass containing fluid (0-20 H.U.) extending from abdomen
into chest through aortic hiatus behind the diaphragmatic crura.
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PNEUMOMEDIASTINUM
Incidental, asymptomatic or chest pain which worsens by breathing .
Air tracks up to neck surgical emphysema.
Causes :
1. Perforation of esophagus osophoscopy or Mallory-Weiss.
2. Rupture of trachea bronchoscopy or trauma.
3. Asthma, IPPV.
4. Whooping cough.
5. Pneumoperitoneum.
Radiologically :
Plain :
- Translucent streaks of gas outlining bl.Vs & other structures with displacement
of the parietal layer of the pleura laterally.
- Lateral film air behind sternum or heart.
Acute mediastinitis :
- Chest pain + fever.
- Mediastinum is widened & edematous houtline.
- Pleural effusion.
- Occasionally abscess.
Mediastinal hemorrhage :
- Trauma
- Leaking aortic aneurysm.
- Plain: widened medistinum, spinal fracture, pneumo or hydrothorax.
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PNEUMONIAS
Pneumonia:
Infective consolidation of the lung (replacement of alveolar air by exudate).
(Pathogenic organism)
Pneumonitis :
General term= inflammatory reaction of the lung consolidation.
Bronchopneumonia :
Multifocal (bronchocentric) infection based on the pulmonary lobule & spreads
along the bronchial axis.
I- Lobar pneumonia :
Pathology :
1. Unifocal.
2. Centered on distal air spaces (alveoli).
3. Rapid spread across the pores of khon uniform consolidation.
4. Spare distal airway.
Radiologically :
1. Homogenous non segmented consolidation.
2. As airways are not involved & remain patent, so there is no volume loss & air
bronchogram is common.
Radiologically :
1. Non homogenous segmental consolidation.
2. May become uniform with confluence later.
3. Air bronchogram is usually absent.
4. Volume loss is common.
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ACUTE PNEUMONIA
Etiology :
A. Bacterial causes :
1. Pneumococci (streptococcus pn). most common
2. Loss common :
- Staph. aureus.
- Gram -ve organisms.
a. Pseudomonas.
d. Legionella pneumophilia.
b. Klebseilla Freidlenders.
e. E coli & proteus.
c. Haemophlus influenza.
3.Anaerobic organisms.
Radiological features :
- Initially peripheral, non segmental, homogenous consolidation limited by fissure.
- Commonly basal and solitary, but it may occur any where and also may be
multifocal.
- Consolidation may not be obvious and suspected by silhouette sign of boundary
effacement.
- Air bronchogram is commonly present (characteristic).
- Kerleys B lines may appear in affected area from temporary over loading of
lymphatics and edema of the interlobar septa.
- No volume loss of the affected lobe.
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STAPHYLOCOCCUS PNEUMONA:
PDF :
1. Debilitated hospitalized patients.
2. Aspiration from URTI (common).
Radiologically :
- Consolidation is classically segmental & patchy at least initially but later
confluent & homogenous.
- Often, Multifocal & bilateral.
- volume loss is common.
- Air bronchogram is unusual.
Features of complication :
1. Due to strong tendency for necrosis that occur in the center of staph.
consolidation cavitation and abscess formation.
2. Rupture of cavity in pleura empyema.
3. Pneumatocele formation: Occurs when consolidation and fluid content of the
abscess cavity are resolved leaving thin hair-line walled air cavities, which
mainly persists for months or disappear leaving no trace.
4. Septicaemic staph pneumonia multifocal, nodular consolidation.
5. Collapse.
PSEUDOMONAS AERUGINOSA:
- Pulmonary infections follow mechanical ventilation or inhalation therapy
- Mainly affects the lower lobes and its radiological pattern is similar to staph
aureus infection.
H. INFLUENZA:
- Mainly associated with chronic lung disease is chronic bronchitis or secondary
invader in influenza virus infection.
- Has no characteristic radiographic pattern.
ANAEROBIC PNEUMONIA
Differs from other bacterial pneumonia in that :
1. Often clinically subacute or chronic with prominent systemic symptoms.
2. Results commonly from aspiration of infected oral contents.
Radiologically :
- Consolidation is uni or multifocal & tends to occupy segments favored by
aspiration eg (posterior upper / Apical lower/ postero basal), more on the RT
side.
- Homogenous, but usually cavitation lung abscess.
- Empyema is common bronchopleural fistula.
MYCOPLASMA PNEUMONIA:
Mycoplasma pneumoniae is an organism intermediate between bacteria and virus.
It is one of organisms produce primary atypical pneumonia which are:
Causes of primary atypical pneumonia :
1. Adenovirus.
4. Toxoplasma.
2. Psittacosis - Chlamydial
5. Mycoplasma
3. Q fever = Rickettsial.
VIRAL PNEUMONIA:
- Common in infants and children.
- In adult, viral pneumonia may be primary as in influenza, or as a part of
generalized viral illness in varicella.
- Radiologically: wide spread nodules, interstitial streaks from hila, mediastinal &
hilar adenopathy.
INFLUENZAE
Predisposing Factors: old age, debilitated persons.
Radiologically :
- It begins a few days after the onset of symptoms.
- Extensive bilateral confluent consolidation which if patient survives, may be
be followed by fibrosis.
VARICELLA
Typically affecting young adults.
Predisposing f: Lymphoma, pregnancy.
Radiologically:
- Characteristically, widespread 5-10 mm nodules, which may simultaneously
come and go in different areas.
- Nodules, usually resolve in a week but it may persist.
- 20% of the opacities calcify.
RICKETSIAL PNEUMONIA:
The most common ricketsial lung infection is Q fever, which is caused by coxiella
burnetti, which is mainly acquired from sheep and cattle.
Radiologically :
- One or more rounded segmental consolidations in the lower zone.
- Linear areas of collapse (common).
- Resolution mainly slow.
CHLAMYDIAL PNEUMONIA:
The commonest lung infection is ornilhosis caused by chlamydia Psittaci, which is
acquired from sick birds.
Radiologically :
- Variable pattern: lobar, patchy or miliary consolidation.
- Slow resolution.
2. Pulmonary gangrene :
- Pneumonia thrombosis of intrapulmn Vs gangrene to pulmn. area supplied
by these Vs.
- Suspected when a large irreg. cavity develops, containing an irregular
intracavitary body.
- Most common with Klebseilla pn. & strept.
3. Pneumatocele :
- Occurs when consolidation & fluid content of an abscess cavity are resolved,
leaving thin hair-line walled air cavities which mainly persist for months or
disappears leaving no trace.
- Septicemic staph pneumonia multifocal, nodular consolidation.
- Underlying disease eg sequestrated segment, bronchogenic cyst, cavitary
neoplasm, bronchiectasis.
E. Lobar expansion :
- Mainly with Klebseilla pneumonia.
F. Collapse :
- May be seen in resolution phase (esp children) .
- With agents that initially bronchitis or bronchiolitis eg staph aureus.,
rickettsia.
G. Residual scarring :
- Parenchymal & pleural scarring fibroses with volume loss.
Pneumatocele :
Def.: cyst in lung during course of pneumonia (staph aureus).
Cause : tension cyst d.t partial obst. of small branches.
Site : in area of consolidation
Size : variable.
Shape : hair line wall - full of fluid.
Number : multiple or solitary.
Course : resolve.
Compl. : pneumonia + empyaema.
DD : hernia
Emphysematous bullae ( its wall is made of surrounding compressed lung tissue)
RESOLUTION
90% of bacterial (except TB) and non bacterial pneumonias resolve within one month.
When changes persist beyond two months delayed resolution.
N.B:
* Mendelsons syndrome :
Chemical pneumonia, caused by aspiration of acid gastric contents during anesthesia
producing intense bronchospasm which is rapidly followed by pulmonary edema.
* Youngs syndrome :
Obstructive azospermia / Sinusitis / Chr. pulmonary infecting eg. bronchiectasis.
Pneumonias (KEY):
PDF/AGE/Complications A,B,C,D,E,F,G & resolution./Path & Rad.
Lobar
BronchoPneumonia
1. Unifocal
1. Multifocal
2. Centered on airways.
3. Khon consolidation
4. Airway obst.
- No volume loss
- Air bronchogram
no air bronchogram
FUNGAL INFECTION
A. Pulmonary Histoplasmosis :
Caused by histoplasma capsulatum (soil dust)
B. Coccidioidomycosis :
Caused by coccidia fungus :
I. Patchy consolidation :
- Mainly lower lobes.
- Cavitation thin wall cavities (grape skin).
- Pleural effusion. / mediastinal LN.
II- Nodular form :
- Nodules (multiple or single) up to 3cm.
- Mainly upper lobes.
- Cavitation thin wall cavities (resembles TB) DD: miliary TB.
- Calcify.
- Rare : Miliary pattern due to blood dissemination.
C. Actinomycosis :
- Commensal in oropharynx (normally):
Aspiration lower lobe pneumonia (dependant) abscess formation,
empyema, rib osteomylitis
- Sinuses open on skin yellow sulfur granules.
D. Aspergillosis :
Aspergillus fumigatus fungus. Three forms :
DD :
1. Blood clot in a cavity.
2. Cavitary sq. cell C.
2. Invasive aspergillosis :
- Pneumonia in immunocompromised pt.
- No characteristic radiological pattern :
* Necrotizing bronchopneumonia with abscess formation.
* Single or multiple nodules (1-5cm) which may cavitate.
* Organizing lobar pneumonia.
* It can mimic with an aspergilloma ..... The difference is that it develops in
an apparently previously normal lung tissue.
Radiologically :
A. Acute changes :
- Consists of non segmental areas of consolidation, common upper lobe (loffler $).
- Lobar collapse.
- Branching thick tubular opacities due to distended bronchi with mucus and
fungus (bronchocele).
B. Chronic changes :
- Consists of bronchial wall thickening with tram line shadows.
- Ring formation indicative of bronchiectasis .
- Linear shadows indicative of fibrosis.
F. Blastomycosis :
- Asymptomatic nodule.
- Potential for re-activation.
- Chronic pneumonia.
- Node enlargement.
B. Schistosomiazis :
- Eggs lodge in small pulmn. Arteries (100 m) small granulomas like TB.
- If lodge in large arteries irritation vas. necrosis fibrotic occlusion
pulmn. hypertension (Ayerza dis).
- Diffuse interstitial fibrosis.
C. Protozoa :
1. Pleuropulmonary amoebiasis :
Usually secondary to liver amaebiasis, young adult male .
Radiologically:
- Elevation of hemidiaphragm, pleural effusion / or thickening.
- Basal band shadow (discoid atalectasis).
- When liver abscess erodes ! diaphragm basal non segmental consolidation
cavitates & fistulae develops between air way & pericardium.
- Blood spread consolidation or abscess in part away from ! diaphragm.
Diagnosis :
1. US liver.
2. Serological test.
3. Also aspiration biopsy guided by U/S is valuable.
2. Toxoplasmosis :
- Human acquisition is from cats.
- Presented as primary atypical pneumonia and mediastinal lymphadenopathy.
3. Pneumocystitis carinii infection :
Only expressed in immunocompromised patients.
Radiologically :
- Diffuse bilateral pulmonary opacification like pulmonary edema, homogenous
with air bronchogram.
- Focal emphysema may occur, where multiple air cysts with air fluid level may
be seen, which may complicate with pneumothorax and pneumomediastinum.
D. Hydatid Disease :
Infection with the tape warm Echinococcus granuloses.
Radiologically :
The cyst is unilocular, smoothly spherical and of homogenous density,
calcification is rare.
Complication :
- Infection
- Rupture:
* into ! pleural cavity or a bronchus.
* Partial replacement of fluid by air (fluid level.)
* Rupture of a liver cyst into ! right lung produces a basal opacity from lobar
infection or atalectasis-pleural effusion.
TC99m labelled IDA hepatic defect.
Divisions :
1. Intralobar : lying within the lung, usually posteriorly in left lower lobe. Rt.
lower lobe is the next most common site.
Radiological appearance:
Plain:
* Soft tissue mass in posterior part of lower lobe close to the diaphragm
(> on lt.side).
* if connected to ! bronchial tree air containing cystic masses air fluid levels
(infection).
Bronchography:
* ?? c.m. rarely enters the lesion.
*Bronchial tree is spread around the mass & is typically complete with no of its
divisions.
Angiography:
* derives its bl. supply from ! descending thoracic aorta.
* venous drainage is via the pulmonary system or IVC.
II. Extra lobar : The non-functioning portion of the lung (sequestrated portion)
develops enclosed in its own pleura.
It is much less common than intralobar sequestration & is interposed between inferior
surface of lt lower lobe & diaphragm + other congenital anomalies (found at autopsy).
Angiography:
* arterial supply is frequently from abdominal aorta.
* venous drainage is via IVC, azygous or portal venous system.
C/P : Recurrent infection in part of a lung with unusual abscess, cavity or cyst esp
at left lung base.
LUNG ABSCESS
(Localized suppurative inflammation
of lung)
Complications :
I-Local:
1. Local extension
2. Hemoptysis
3. Fibrosis & bronchiectasis
4. Chronicity amyloidosis.
5. Corpulmonale
II. General:
1. Systemic pyemia septicemia
2. Myocarditis.
3. Toxemia
3. Brain abscess.
4. Moist gangrene.
Radiological features :
I. Abscess arising on cavitation of consolidation :
1. Consolidation : Primary Pn. or Secondary Pn. (br. obst).
2. Site : uncommon above clavicles.
3. Size : Rapid increase indicates air trapping tension cavity.
4. Shape:
- Air fluid level within lumen
- Inner lining : Shaggy smooth
- Wall : thick thin
5. Surrounding lung tissue :
- markings & patchy consolidation (inflam).
- lobe containing abscess bulging of fissures.
6. Fate : Resolution or lung damage (fibrosis & or bronchiectasis)
6. Caplan nodule.
DD: Lung cavities
1. Infective i.e Abscess
Staph / Klebsiella / TB /Aspiration / Gram-ve / Fungi / Hydatid
2. Neoplastic:
Carcinomas of bronchus / Metastases / Hodgkin
3. Vascular:
Infarction
4. Abnormal lung:
Cystic bronchiectasis / sequestrated segment / bronchogenic cyst
5. Granulomas:
Wegeners granulomatosis /Rheumatoid nodules caplan / Progressive massive
fibrosis pneumoconiosis / Sarcoidosis.
6. Traumatic
Haematoma / Traumatic lung cyst
Tuberculosis
Body reactions :
I. Proliferative reaction Tubercle made of :
1. Macrophage phagocytose bacilli epithelioid cells.
2. Release of tuberculoprotein (cell mediated immune response) sensitized Tlymphocytes.
3. Fusion of several epithelioid cells Langhans giant cells
* Caseation of tubercle center occurs by lymphokines
4. Lymphocytes & fibroblasts usually surround epitheloid cells.
Fate of tubercle
1. High immunity: complete fibrosis / fibrous capsule & central calcification.
2. Low immunity: fuse to form bigger tuberculous patch / spread (local,
lymphatic, blood. or natural passages).
Classification of TB:
I. Primary pulmonary TB: Ghons.
II. Post primary pulmonary TB: (reactivation or reinfection)
1. Chronic fibrocaseous TB.
2. Acute (Miliary TB of the lung / tuberculous bronchopneumonia)
Post Primary TB :
1. Early fluffy opacities.
2. Chronic active opacities + strands + cavities.
3. Old healed fibrosis + calcification.
Course :
I. Slow resolution leaving only the calcification (no fibrosis in few cases).
II. Spread : Direct, hematogenous or bronchial.
III. Encapsulation & Reactivation.
DD :
1. Pneumoconiosis
2. Sarcoidosis
Complications :
1. Haemoptysis, suppurative bronchitis.
2. Pleura pleurisy, empyema, pneumothorax.
3. TB heart & ribs Pulmonary hypertension HF.
4. Blood bone, brain, male & female genital
5. TB bronchopneumonia, laryngitis , tongue entritis.
6. Amyloidosis.