IP in senile cataract subjects

窑Clinical Research窑

Idiopathic phacodonesis in senile cataract patients in

Qinghai, China

Foundation item: Supported by Lifeline Express Hong Kong

·KEYWORDS: phacodonesis; lens nucleus; zonular dialysis
Foundation, China
DOI:10.3980/j.issn.2222-3959.2011.05.10
1
Department of Ophthalmology, Peking Union Medical College
Hospital, Chinese Academy of Medical Sciences & Peking Union
Medical College, Beijing 100730, China Liu XW, Wang Z, Yu WH, Wang ZW, Zhang YN, Liu JJ, Sui RF.
2
Department of Ophthalmology, Beijing Hospital, Beijing 100730, Idiopathic phacodonesis in senile cataract patients in Qinghai, China.
China 2011;4(5):508-512
3
Department of Anesthesiology, Peking Union Medical College
Hospital, Chinese Academy of Medical Sciences & Peking Union INTRODUCTION

P
Medical College, Beijing 100730, China hacodonesis is present if lens trembled upon movement
Corresponding to: Rui-Fang Sui. Department of Ophthalmology, of the eye during slit-lamp examination [1]. Zonular
Peking Union Medical College Hospital, Chinese Academy of apparatus is the main support system of human lens,
Medical Sciences & Peking Union Medical College, Beijing
weakness in the zonules could cause instability of the lens,
100730 China. paddyliuxw@hotmail.com
leading to complication during cataract extraction surgery.
Received:2011-05-03 Accepted:2011-09-10
Phacodonesis is the major sign of weakness of the zonular
apparatus [1,2]. In severe cases, iridodonesis, subluxation or
Abstract
dislocation of the lens could be noted.
· AIM: To investigate the frequency of idiopathic While many studies have documented pseudoexfoliation
phacodonesis (IP) in senile cataract subjects and the syndrome as a cause of weakness in the zonular apparatus [1,3-5],
short-term clinical outcomes following cataract surgery. other reports indicated that injury, laser [6], vitrectomy,
· METHODS：This institutional case-control study included glaucoma surgery, glaucoma [7], uveitis, aging, retinitis
1301 consecutive low-income cataract subjects from June to pigmentosa [8]
, diabetes, Marfan's syndrome [9],
November 2009. Anterior segment were carefully evaluated homocystinuria[10] and Weill-Marchesani syndrome [11,12] could
with dilated pupil under slit-lamp. IP were screened and also weaken the lens apparatus. There remains some
graded by a criteria set by the authors. Risk factors, surgical
phacodonesis cases without known cause [13].
outcomes, and operative complications were analyzed.
During the period from June to November 2009, the
· RESULTS：A total of 42 subjects (3.2% ) with IP were Chinese Lifeline Express Medical Team, an organization
diagnosed and classified as grade 1 (36 subjects), grade 2 (5 aimed to cure blindness from cataract for the poor, was in
subjects) and grade 3 (1 subject). Harder lenses and Qinghai province. Qinghai is a located in north-east of the
intumescent cataracts were observed in the IP group than the
Qinghai-Tibet Plateau. Due to high altitude and high
control group ( <0.05). Logistics regression test also
ultraviolet radiation intensity, the incidence of age-related
indicated the main risk factor was the hardness of the lens.
The incidence of zonular dialysis during surgery was 23.8%
cataract is 0.3% . Cataract is the most common cause of
(10 eyes), which was significantly higher than the controls blindness and visual impairment among adults. As members
(0.7% , <0.001). Visual outcomes of the two groups were of this team, we found some cases of phacodonesis in
not statistically or clinically significant. cataract subjects without the above known causes, so we
named this "idiopathic phacodonesis (IP)". We focused on
·CONCLUSION: Hard nucleus and intumescent cataract are
related to IP in senile cataract subjects in Qinghai, China. studying the clinical features, risk factors and surgical
With more care being taken, grade 1 and some of the grade outcomes of this disease.
2 IP subjects achieved similar surgical outcomes as compared For economic and other reasons, the study could only be
to controls. conducted for a short period, and long-term follow-up was
508
 陨灶贼 允 韵责澡贼澡葬造皂燥造熏 灾燥造援 4熏 晕燥援 5熏 Oct.18, 圆园11 www. IJO. cn
栽藻造押8629原愿圆圆源缘员苑圆 8629-83085628 耘皂葬蚤造押陨允韵援 圆园园园岳员远猿援糟燥皂
not possible. Further study on the pathology of IP and was injected into the anterior chamber to stain the capsular
long-term evaluation on the surgical outcomes will if necessary and continuous curvilinear capsulorhexis
published in future reports. (CCC), hydrodissection, and hydrodelineation followed by
MATERIALS AND METHODS phacoemucification or extracapsular cataract extraction
Materials Subjects for this study were collected from a (ECCE) was performed depending on the the hardness of
general ophthalmology practice in a group-model health nucleus classification. (Nucleus hardness in all eyes was
maintenance organization,Lifeline Express. 1523 low-income classified as grade1-5. Grades 4 and 5 were considered as
cataract subjects were recruited by Qinghai Health Bureau hard nucleus in this article). After aspiration of the cortex, a
from all districts of Qinghai province. Most of them were of PMMA (polymethyl methacrylate, Eye Good Medical Co.
Han ethnicity, (763, 50.1%), other ethnicities included were Ltd, Zhuhai, China) intraocular lens was implantated into
Hui (239,15.7%), Sara (181,11.9%), Tibetans (167,11.0%), the capsular bag. Anterior vitrectomy was performed when
Tu (110,7.2% ), and Mongolians (63,4.1% ) minorities. the posterior capsular was compromised and vitreous loss
Detailed past medical history was collected including occurred. All operations were performed by two
diabetes, hypertensive disease, ocular trauma, ocular experienced ophthalmologists (W.H.Y & X.W.L). Due to
surgery, refractive error and ocular disease. the financial reason, majority of the subjects could be only
Methods All subjects underwent a complete ophthalmologic accommodated and followed-up by our team for 3-7 days,
examination including best-corrected visual acuity (BCVA), Limited long-term follow-up information could be obtained
slit-lamp evaluation of the anterior segment with dilated from local health bureau.To evaluate the zonular apparatus,
pupils, detailed fundus assessment, B-mode ultrasound and some of the subjects who were available and lived close to
contact A-scan ultrasound for axial length measurements. the train were evaluated by ultrasound biomicroscopy
Phacodonesis was diagnosed during the preoperative dilated (UBM, Suowei Electronic Technology. Co. Ltd. China)
slit-lamp examination by one doctor and confirmed by preoperatively and 4 weeks postoperatively.
another. The information of lens nucleus hardness (which Statistical Analysis Data were analyzed with SPSS 13.0
was graded by Emery and Little [14] system), intraocular data processor for Windows. Means and standard deviations
pressure, retinal pathology, axis length, lens stability and were used to compare age, axial length, and anterior
intraoperative complications were recorded immediately. chamber depth. Pearson chi-square tests were used to
Subjects with pseudoexfoliation, uveitis, diabetes mellitus, compare the baseline categorical characteristics and
ocular trauma, previous ocular surgery, glaucoma, Marfan's incidence of intraoperative complications between subjects
syndrome, high myopia and other known disease which with and without IP. A logistic regression model for
could cause lens dislocation were excluded in this study. multiple analyses subsequently was used. A value of less
Also, Morgagnian cataract which could cause the movement than 0.05 was considered statistically significant.
of the nucleus alone was excluded. RESULTS
We established the criteria to grade the IP. Grade 1, Total subjects included in this study were 1301. The mean
phacodonesis could be found by careful slit-lamp age of subjects with idiopathic phacodonesis (IP) was 67.4依
examination, without iridodonesis or visible zonular 9.8 years (range 40 to 84 years, 82 eyes of 42 subjects),
dialysis; Grade 2, phacodonesis could be easily noticed by including 18 males (42.9%) and 24 females (57.1%). The
slit-lamp examination, with or without iridodonesis, also no mean age of subjects without phacodonesis (the controls)
zonular dialysis noticed; Grade 3, phacodonesis could be was 66.4依10.1 years (range 41-91 years, 1259 eyes of 1259
easily noticed by slit-lamp examination, acompanied by subjects), including 584 males (46.4% ) and 675 females
iridodonesis and zonular dialysis and even dislocation of the (53.6% ). The preoperative BCVA ranged from light
lens. According to Lifeline Express policy, only one eye perception to 0.3 on the Snellen Chart. Phacodonesis was
could be operated in this program for each subject, so our observed bilaterally except in two subjects, one with dense
study only included the operative eyes. corneal opacity and the other who had underwent remote
Surgery was performed mostly using topical anesthesia with enucleation in the other eyes. There were no significant
a few subjects having retrobulbar anesthesia. Preoperatively, difference in phacodonesis between the right eyes and the
subjects were given 1 drop each of tropicamide 1% , left eyes in all subjects (two independent samples tests,
phenylephrine 0.25%(Mydrin-P),oxybuprocaine hydrochloride Mann-Whitney U test =-0.388， =0.698). Only the 42
0.04% (Benoxil)，and repeated every five minutes for four operated eyes were included in this study.
sets. All cases underwent a superior 5.5mm or more scleral In our study, we identified 36 eyes with grade 1
pocket incision, 0.06% trypan blue (Aurolab, India) 0.1mL phacodonesis, and 5 eyes with grade 2, 1 eye with grade 3.
509
IP in senile cataract subjects

There was no difference between the mean age of the IP Table 1 Distribution of nucleus hardness grades and
intumescent cataract in the IP subjects and the controls n
subjects and the controls ( =0.61, =0.54). Neither did
Nucleus grade Cortex
the mean axial length between the two groups differ (23.59依 1-3 4-5 Non-intumecent Intumescent
2.43mm in IP group & 23.50依2.33mm in control group, = IP 16 26 27 15
control 517 742 1249 100
0.25, =0.80). More eyes had harder nucleus (grade 4-5) c2 7.26a 38.90b
a b
in the IP group than those in the control group (Pearson Pearson Chi-squared test, P=0.007 Pearson Chi-squared test,
P<0.001
chi-square test, 2=7.26， =0.007).In addition, more
intumescent but not mature or hypermature cataract was Table 2 Intraoperative complications of the IP and control groups
n
observed in the IP group(Pearson Chi-square test, 2=38.90，
IP (n=42)
Complication Control
<0.001,Table 1). Grade1 Grade 2 Grade3
/IOL Total (n=1249)
We identified several risk factors that may be associated n=36 n=5 n=1
ZDa 5 4 1 10 9
with IP, including: age, sex, IOP, the depth of the anterior 3 CHs ZD 4 2 0 7 8
chamber, axial length, hardness of the lens nucleus, diabetes 6 CHs ZD 1 1 0 2 1
>6CHs ZD 0 1 1 2 0
and cardiovascular diseases. We tested all these risk factors Vitreous loss 0 0 1 1 3
using logistic regression, which showed hardness of lens as Capsule rapture 0 1 1 4
Suture fixed IOL 0 1 0 1 2
the main risk factor( 2=6,846 0.011)associated with IP, ZD= zonular dialysis CHs= clock-hours aPearson Chi-square test,
and the logistic regression equation was logit =-4.238+ c2=8.37, P<0.001
0.234X1. With an increase in lens hardness grade by one, Table 3 Zonular dialysis in ECCE and phacoemulsification
the relative risk increases 1.28 times. procedure n
Zonular dialysis was found intraoperatively in 10 eyes IP (n=42) Control(n=1459)
PE ECCE PE ECCE
（10/42,23.8%）and one of them (1/42,2.4% ) developed
ZD 2 8 1 8
vitreous loss during surgical procedure in the IP group. Up
No ZD 17 15 811 439
to 3 clock-hours of zonular dialysis occurred in 6 eyes Total 19 23 812 447
(6/10,60%, 4 eyes with grade I IP, 2 eyes with grade 2 IP); c2 3.38 11.28
up to 6 clock-hours of zonular dialysis was observed in 2 P 0.066 0.001
cases (2/10, 20%, 1 eye was grade 1 IP, 1 eye was grade 2
IP ); more than 6 clock-hours of zonular dialysis was seen in
significantly improved from baseline, except in one subject
2 cases (2/10 20%, one was grade 2 IP, and the other was
whose BCVA remained at counting finger due to advanced
grade 3), one of them with vitreous loss had anterior
age-related macular degeneration. There was no significant
vitrectomy and no IOL implanted due to poor cooperation,
difference in the BCVA improvement between the 2 groups.
the other without vitreous loss had scleral fixated IOL. Most
Ultrasound biomicroscopy (UBM) was used to evaluate the
common site of zonular dialysis was found in the
zonular apparatus of 12 IP subjects and 23 controls who
inferotemporal or inferonasal quadrants (7 eyes), and a few
were available pre- and post-operation. Cross-sectional
were encountered in the superior quadrants (2 eyes). In zonular UBM images were obtained circumferentially at
control group, 9 eyes (0.72%) were found to have zonular eight evenly spaced locations.
dialysis. There was a significant difference in the incidence UBM showed that grade 1 IP subjects' zonular apparatus
of zonular dialysis between the IP group and control group appeared similar to controls (Figure 1); however, in some of
(Pearson Chi-square test, 字2=8.37, <0.0001,Table 2). the grade 2 IP subjects, the zonules were uneven, slack or
Phacoemulsification was performed in 812 subjects in the elongated compared with the controls. And there is a gap
control group, and 19 in the IP group. ECCE was performed between the iris and the lens, which could be a reason for
in 447 subjects in the control group and 23 in the IP group. phacodonesis and iridodonesis (Figure 2). After
In the IP group, 2 cases of zonular dialysis occurred with phacoemulsification, phacodonesis of the IOL became more
phacoemulsification, but 8 cases when ECCE was pronounced, the gap between the lens and iris became larger
performed (Pearson Chi-square test, 字2=3.38, =0.066) , in than in preoperative images (Figure 3). In grade 3 eyes, the
control group, 1 case with phacoemulsification and 8 with dialysis of the zonules and the dislocation of the lens were
ECCE(Pearson Chi-square test, 字2=11.28, =0.001,Table 3). easily observed (Figure 4).
Follow-up period was limited to 3-7days. IOL dislocation Transient postoperative high IOP was found in 3 cases of IP
was not observed in any subjects. Postoperative BCVA subjects, but all resolved within 3 days.
510
 陨灶贼 允 韵责澡贼澡葬造皂燥造熏 灾燥造援 4熏 晕燥援 5熏 Oct.18, 圆园11 www. IJO. cn
栽藻造押8629原愿圆圆源缘员苑圆 8629-83085628 耘皂葬蚤造押陨允韵援 圆园园园岳员远猿援糟燥皂
ethnic or sexual predilection for IP.
In the literature, phacodonesis and dislocation of lens are
mostly associated with pseudoexfoliation. In our study, most
of the known risks to phacodonesis were excluded, the
reason of instability of the lens is still not clear, so we
named this sign "idiopathic phacodonesis" (IP). No poor
Figure 1 Grade 1 IP patient, the images of the zonles was as
papillary dilation was observed in the IP subjects, a sign
normal as normal zonular images, the iris and the lens were
commonly seen in pseudoexfoliation syndrome [15,16].
contact
The reason for weakness of the zonules remains unclear, but
we found that hardness of the lens was one of the major risk
factors, which should also be related to the age of the
subject. But in our study, the relationship between IP and
age was not significant. The authors presumed that is due to
the small sample size of subjects with IP. Although
intumescent cataract is not a risk factor for IP in logistics
Figure 2 Grade 2 IP ( the only one without intraoperative regression test in our study, the rates of intumescent cataract
zonular dialysis), which showed the separation of the iris and subjects in IP group was significantly higher than in the
the lens, although the zonular seemed as normal as that of control group, so we still considered intumescent cataract to
the controls be closely related to IP. No difference was found in axial
length or anterior chamber depth between the two groups.
We hypothesize that hard nucleus and intumescent cataract
could cause degeneration of the zonular apparatus, this will
need pathological studies to confirm.
With UBM examinations, no abnormal image was observed
in preoperative and uneventful surgery grade 1 IP eyes.
However, in the grade 2 subjects, even though the
Figure 3 The same eye of Figure 2, postoperative zonules
image, showed bigger gap between the iris and the lens, preoperative zonules image appeared "normal", some of the
tensionless and lengthened of the zonules eyes showed non-contact of the lens and the iris, some of
the eyes showed the elongated zonules. In postoperative
images, there was discontinuity of the zonules, which could
be due to damage of zonules during surgery.
Shingleton [17] found that 60% of subjects with zonular
weakness confirmed by phacodonesis developed vitreous
loss during surgery. Artzen [4]
reported phacodonesis
Figure 4 A grade 3 IP eye, which showed dialysis of the was significantly associated with capsular complication
zonles and dislocation of the lens during cataract surgery. In our study, we also found that the
IP subjects more frequently suffered from zonular dialysis
DISCUSSION (26.2% ) during cataract surgery than the control group
In 1970，Bartholomew [1] reported 7 cases (9 eyes) of (0.7% ). The more severe the phacodonesis was, the more
phacodonesis after investigation of 300 cataract eyes and the likely for zonular dialysis occured during cataract surgery.
fellow eyes of 195 subjects with displacement of the lens. Most of the zonular rupture in surgery occurred in the
Six of them were attributed to pseudoexfoliation, only one inferonasal or inferotemporal quadrants of eye, which is
case was thought to be idiopathic phacodonesis. He assumed probably due to increased stress to inferior zonules during
that phacodonesis was the transitory stage before complete phacoemulsification or ECCE. With surgical tools such as
lens dislocation. The prevalence of IP has not been reported capsular tension rings [18,19] or surgical technique such as
in literature, the 3.2% prevalence in our study is among the scleral-fixation IOL by experienced surgeons, most of the
selected cataract elder subjects in Qinghai province, phacodonesis subjects could achieve good postoperative
including several ethnic groups. To determine the general visual outcome [16]. In our study, capsular tension ring was
prevalence, further studies are needed. Due to the small not available, so for some subjects we performed
number in the IP group, we could not implicate if there is an scleral-fixated IOL implantation.
511
IP in senile cataract subjects

In this study, we found modern phacoemulsification could 3 Skuta GL, Parrish RK, 2nd, Hodapp E, Forster RK, Rockwood EJ. Zonular
dialysis during extracapsular cataract extraction in pseudoexfoliation syndrome.
be safer for zonules than the ECCE in both IP (although not
1987; 105:632-634
significant) and the controls. Katsimpris [20]
also believe
4 Artzen D, Lundstrom M, Behndig A, Stenevi U, Lydahl E, Montan P. Capsule
that phacoemulsification induces less stress on the zonules complication during cataract surgery: Case-control study of preoperative and
than ECCE. But, in our study, most ECCE surgeries were intraoperative risk factors: Swedish Capsule Rupture Study Group report 2.
performed on brunescent and white cataracts which would 2009;35:1688-1693

be of challenge with either phacoemulsification or ECCE 5 Drolsum L, Ringvold A, Nicolaissen B. Cataract and glaucoma surgery in
pseudoexfoliation syndrome: a review. 2007;85:810-821
techniques[21].
6 Seong M, Kim MJ, Tchah H. Argon laser iridotomy as a possible cause of anterior
Jehan [22]
reported 8 of pseudoexfoliation eyes with late dislocation of a crystalline lens. 2009:190-192
spontaneous intraocular lens dislocation 57-115 months after 7 Yang J, Lu Y, Luo Y, Wang L. Clinical efficacy of management of zonular
uneventful phacoemulsification in pseudoexfoliation abnormalities with capsular tension ring: a two-year follow-up study.
syndrome. However, Nagashima [15] reported 67 eyes with 2007;43:519-524
8 Lee HJ, Min SH, Kim TY. Bilateral spontaneous dislocation of intraocular lenses
pseudoexfoliation who had phacoemusificaiton, after a mean
within the capsular bag in a retinitis pigmentosa patient.
follow up of 54.1 months, no IOL dislocation was noted.
2004;18:52-57
For our subjects, we were not able to perform long-term 9 Doyle A, Hamard P, Puech M, Lachkar Y. Asymmetric pigmentary glaucoma in a
follow-up, and some medical information can be obtained patient with Marfan's syndrome. 2005;243:
from the local health bureau which may provide further 955-957
information related to long term surgical outcomes. 10 Mulvihill A, O'Keeffe M, Yap S, Naughten E, Howard P, Lanigan B. Ocular
axial length in homocystinuria patients with and without ocular changes: effects of
Phacodonesis in these subjects may be due to zonular
early treatment and biochemical control. 2004;8:254-258
degeneration, which was confirmed preoperatively by UBM 11 Jethani J, Mishra A, Shetty S, Vijayalakshmi P. Weill-Marchesani syndrome
and/or during surgery. Although only a small part of our associated with retinitis pigmentosa. 2007;55:142-143
subjects were available for UBM evaluation of their zonular 12 Burakgazi AZ, Ozbek Z, Rapuano CJ, Rhee DJ. Long-term complications of
apparatus, we still identified some clues of zonular fragility, iris-claw phakic intraocular lens implantation in Weill-Marchesani syndrome.
2006;25:361-363
such as: large gap between the iris and the lens, elongated
13 Moreno-Montanes J, Sainz C, Maldonado MJ. Intraoperative and postoperative
and laxity of the zonules and even rupture of the zonules.
complications of Cionni endocapsular ring implantation.
To gain more detailed information by UBM, further study 2003;29:492-497
should be carried out. 14 Emery JM Little JH. Phacoemulsification and aspiration of cararact : surgical
As a sign of incipient lens dislocation， phacodonesis is techniques, complications, and rusults. Mosby 1979:179-202

significant and its recognition may be taken as an indication 15 Nagashima RJ. Decreased incidence of capsule complications and vitreous loss
during phacoemulsification in eyes with pseudoexfoliation syndrome.
for lens extraction before actual dislocation, which can
2004;30:127-131
make surgery more challenging. If surgery is to be 16 Susic N, Kalauz-Surac I, Brajkovic J. Phacoemulsification in pseudoexfoliation
performed, outmost care should be taken to prevent (PEX) syndrome. 2008;47:87-89
uncontrolled lens displacement and possible vitreous loss, 17 Shingleton BJ, Heltzer J, O'Donoghue MW. Outcomes of phacoemulsification in
and these subjects should be operated on by experienced patients with and without pseudoexfoliation syndrome.
2003;29:1080-1086
surgeons. Surgery procedure could be as safe as in controls
18 Takimoto M, Hayashi K, Hayashi H. Effect of a capsular tension ring on
when only mild phacodonesis (grade 1) is identified, but
prevention of intraocular lens decentration and tilt and on anterior capsule
complication rate is significantly increased in advanced contraction after cataract surgery. 2008;52:363-367
phacodonesis (grade 2 and grade 3). 19 Marques DM, Marques FF, Cionni RJ, Osher RH, Freitas LL. Evaluation of the
Acknowledgments:The authors thank Dr. Lan Chang for modified capsular tension ring in cases of traumatic lens subluxation.

editorial assistance. Many thank Dr. Jinlian Zhu, Dr. Ai 2007;70:746-751

20 Katsimpris JM, Petropoulos IK, Apostolakis K, Feretis D. Comparing
Guo, and Lifeline Express officers and Qinghai Health
phacoemulsification and extracapsular cataract extraction in eyes with
Bureau officers for help in coordinating subject recruitment pseudoexfoliation syndrome, small pupil, and phacodonesis.
and schedules. Thanks to Dr. Gangwei Chen for his 2004;221:328-333
expertise in UBM. 21 Narendran N, Jaycock P, Johnston RL, Taylor H, Adams M, Tole DM, Asaria
REFERENCES RH, Galloway P, Sparrow JM. The Cataract National Dataset electronic multicentre
1 Bartholomew RS. Phakodonesis. A sign of incipient lens displacement. audit of 55,567 operations: risk stratification for posterior capsule rupture and
1970, 54:663-666 vitreous loss. 2009;23:31-37
2 Scherer M, Bertelmann E, Rieck P. Late spontaneous in-the-bag intraocular 22 Jehan FS, Mamalis N, Crandall AS. Spontaneous late dislocation of intraocular
lens and capsular tension ring dislocation in pseudoexfoliation syndrome. lens within the capsular bag in pseudoexfoliation patients. 2001;
2006; 32:672-675 108:1727-1731

512