Perimetry and Visual Fields

To determine whether we could establish evidence-based pass/fail criteria for perimetry in the context of the European visual field standards for driving. Methods: This two-centre, cross-sectional study included participants with binocular visual field loss that had led to revocation of a group-1 driving licence. The participants underwent cognitive and binocular visual testing, including the European Driving Test (EDT), a perimetry algorithm that adheres to the European visual field standards. We used a high-fidelity driving simulator to compare the driving ability of these participants with healthy controls. Two driving instructors classified each driving test as passed or failed. Receiver operating characteristic (ROC) analysis and area under the curve (AUC) determined the ability of perimetry to discriminate between passed and failed driving tests. Results: The study included 70 participants with visual field loss and 37 controls. A non-significantly higher proportion of controls passed the driving test (75% vs. 63%; p = 0.22). In ROC analysis, contrast sensitivity performed best (AUC of 0.73), followed by NEI VFQ-25 (AUC of 0.64). Peripheral visual field (AUC of 0.56) and central visual field (AUC of 0.47) performed weaker. Combining the central and peripheral visual field, and their interaction, increased AUC to 0.63. Conclusion: Perimetry was a poor predictor of simulator-based driving test result, and we could not establish appropriate pass/fail criteria for the European visual field standards. Because perimetry is not an accurate diagnostic tool for fitness to drive, a practical driving assessment should be performed in case of doubt.

Hypophyseal adenomas can present with or without minimal visual disturbances. We present a case of a 40year-old male with a hypophyseal adenoma, highlighting bitemporal peripapillary retinal nerve fiber layer (NFL) thinning on optical coherence tomography (OCT) as a major sign of chiasmal damage despite minimal asymmetrical nonspecific changes detected on initial visual field testing. The bitemporal NFL thinning prompted further evaluation with MRI, which confirmed the presence of a macroadenoma of the hypophysis. Despite the large adenoma, treatment with cabergoline led to regression, and the patient's visual field improved. This case underscores the importance of OCT in detecting subtle structural changes associated with pituitary tumors, as it can facilitate early diagnosis and prompt intervention for optimal visual outcomes.

Glaucoma is the main cause of irreversible blindness and is the second leading cause of blindness worldwide. (1) This is a fact that more number of glaucoma patients are being treated by comprehensive ophthalmologists as compared to the glaucoma specialists however, the complicated cases are managed by glaucomatologist more often. This is alarming to note that about 50-90% of glaucoma patients remain undiagnosed in the population. (2-4) The problem of under diagnosis and over treatment is a reality and has been discussed appropriately in an editorial earlier. (5) The purpose of present editorial is to highlight some important aspect which are often ignored by most of us leading to mismanagement. We should always be reminded of the following facts in relation to glaucoma, so that appropriate management can be planned.

The external morphology of lateral line canals was described for Dasyatis matsubarai. Despite the distribution of canals is similar to the most dasyatid species, the number of tubules and branches was different, especially to hyomandibular canal on the both dorsal and ventral surfaces.

Background More than half of the adults with visual impairment experience severe symptoms of fatigue, with a negative impact on daily life. Since there is no evidence-based treatment to reduce fatigue in adults with visual impairment, we developed E-nergEYEze, an eHealth intervention based on cognitive behavioral therapy and self-management tailored to the needs of visually impaired adults. The aim is to describe the study protocol of a randomized controlled trial testing E-nergEYEze. Methods A randomized controlled trial will be conducted to investigate the cost-effectiveness and cost-utility of E-nergEYEze to reduce fatigue severity compared to care as usual from a healthcare and societal perspective. A total of 172 severely fatigued adults with visual impairment will be recruited and randomized to either the E-nergEYEze intervention plus care as usual or to care as usual only (ratio 1:1). Inclusion criteria are having a visual impairment, experiencing severe fatigue (Checklist In...

Low vision affects large number of people globally, which can interfere with daily activities and lower quality of life. Objective: To evaluate the results of the Low Vision Quality of Life Questionnaire (LVQOL) and the National Eye Institute VFQ-25 as measures of patients' quality of life. Methods: Between August-October 2022, a comparative cross-sectional study was carried out at Madina Teaching Hospital, Faisalabad. Through Non-Probability Purposive Sampling Technique, 40 patients were included. Participants who were between the ages of 25 and 55, having visual acuity of less than 6/18 and had a visual field that did not extend more than 10° from the fixation point were considered. Every patient underwent a thorough ocular examination, which included testing for near visual acuity, BCVA, tonometry, fundus examination, and slit lamp bio microscopy. Results: Participants' average age was 47 ± 2.71. 17(42.5%) were female, whereas 23(57.5%) were male. Demographic data were re...

To analyze static visual field sensitivity with topographic models of the hill of vision (HOV), and to characterize several visual function indices derived from the HOV volume. A software application, Visual Field Modeling and Analysis (VFMA), was developed for static perimetry data visualization and analysis. Three-dimensional HOV models were generated for 16 healthy subjects and 82 retinitis pigmentosa patients. Volumetric visual function indices, which are measures of quantity and comparable regardless of perimeter test pattern, were investigated. Cross-validation, reliability, and cross-sectional analyses were performed to assess this methodology and compare the volumetric indices to conventional mean sensitivity and mean deviation. Floor effects were evaluated by computer simulation. Cross-validation yielded an overall R (2) of 0.68 and index of agreement of 0.89, which were consistent among subject groups, indicating good accuracy. Volumetric and conventional indices were comp...

Automated perimetry uses a 3.5 log unit (35dB) range of stimulus contrasts to assess function within the visual field. Using 'Size III' stimuli (0.43°), presenting stimuli within the highest 15dB of available contrast may not increase the response probability at locations damaged by glaucoma, due to retinal ganglion cell response saturation. This experiment examines the effect of instead using 'Size V' (1.72°) stimuli. Luminance increment thresholds for circular spot stimuli of each stimulus size were measured in 35 participants (mean deviation -20.9 to -3.4 dB, ages 52-87) using the method of constant stimuli, at four locations per participant. Frequency-of-seeing curves were fit at each size and location, with three free parameters: mean, standard deviation, and asymptotic maximum response probability. These were used to estimate the contrasts to which each participant would respond on 25% of presentations (c25). Using segmented orthogonal regression, the maximum o...

Purpose: There is a need for more intuitive perimetric screening methods, which can also be performed by elderly people and children currently unable to perform standard automated perimetry (SAP). Ideally, these methods should also be easier to administer, such that they may be used outside of a regular clinical environment. We evaluated the suitability of various methodological and analytical approaches for detecting and localizing VFD in glaucoma patients, based on eye movement recordings.Methods: The present study consisted of two experiments. In experiment 1, we collected data from 20 glaucoma patients and 20 age-matched controls, who monocularly viewed 28 1-min video clips while their eyes were being tracked. In experiment 2, we re-analyzed a published dataset, that contained data of 44 glaucoma patients and 32 age-matched controls who had binocularly viewed three longer-duration (3, 5, and 7 min) video clips. For both experiments, we first examined if the two groups differed i...

Saccade latencies are longer prior to an eye movement to a recently fixated location than to control locations, a phenomenon known as oculomotor inhibition of return (O-IOR). There are theoretical reasons to expect that O-IOR would vary in magnitude across different eye movement tasks, but previous studies have produced contradictory evidence. However, this may have been because previous studies have not dissociated O-IOR and a related phenomenon, saccadic momentum, which is a bias to repeat saccade programs that also influences saccade latencies. The present study dissociated the influence of O-IOR and saccadic momentum across three complex visual tasks: scene search, scene memorization, and scene aesthetic preference. O-IOR was of similar magnitude across all three tasks, while saccadic momentum was weaker in scene search.

Purpose: The learning effect is an essential factor in many psychophysical tests. This study aims to examine the learning effects of Humphrey Field Analyser (HFA) in patients with glaucoma.Study design: Cross-sectional study.Methods: Twenty eyes of 12 patients (10 patients [83.4%] open-angle glaucoma, 1 patient [8.3%] angle-closure glaucoma, and 1 patient [8.3%] secondary glaucoma) were sent to HFA examination for three different sessions of examination. The inclusion criteria were patients with glaucoma who completed three HFA examinations.The results were analysed using ANOVA and Tukey’s post hoc test. The primary outcomes were reliability, global indices, and the threshold sensitivity between the three sessions.Results: Duration to complete the HFA test statistically decreased after the third session (first vs third session: 387 ± 96 vs 307 ± 93 sec; p = 0.017) as well as fixation loss (first vs third session: 0.25 ± 0.19 vs 0.05 ± 0.11: p = 0.001). False-negative results improve...