Detection of Relative Afferent Pupillary Defects Using Eye Tracking and a VR Headset.

Purpose: The purpose of this study was to assess the feasibility of detecting relative afferent pupillary defects (RAPDs) using a commercial virtual reality headset equipped with an eye tracker. Methods: This is a cross-sectional study in which we compare the new computerized RAPD test with the traditional clinical standard using the swinging flashlight test. Eighty-two participants including 20 healthy volunteers aged 10 to 88 years were enrolled in this study. We present a bright/dark stimulus alternating between the eyes every 3 seconds using a virtual reality headset, and we simultaneously record changes in pupil size. To determine the presence of an RAPD, we developed an algorithm analyzing the pupil size differences. For the assessment of the performance of the automated and the manual measurement a post hoc impression based on all available data is created. The accuracy of the manual clinical evaluation and the computerized method is compared using confusion matrices and the gold standard of the post hoc impression. The latter is based on all available clinical information. Results: We found that the computerized method detected RAPD with a sensitivity of 90.2% and an accuracy of 84.4%, as compared to the post hoc impression. This was not significantly different from the clinical evaluation with a sensitivity of 89.1% and an accuracy of 88.3%. Conclusions: The presented method offers an accurate, easy to use, and fast method to measure an RAPD. In contrast to today's clinical practice, the measures are quantitative and objective. Translational Relevance: Computerized testing of Relative Afferent Pupillary Defects (RAPD) using a VR-headset and eye-tracking reaches non-inferior performance compared with senior neuro-ophthalmologists.

MRI signs helpful in the differentiation of patients with anterior ischaemic optic neuropathy and optic neuritis.

BACKGROUND/AIMS: The aim of this study was to identify specific MRI characteristics of anterior ischaemic optic neuropathy (AION) and optic neuritis (ON) that would aid in the differentiation between these two diagnoses. METHODS: We retrospectively analysed a consecutive case series including all patients with an MRI study of brain and orbit and the clinical diagnosis of either ON or AION. We examined the scans for restricted diffusion of the optic nerve, optic sheath diameter, enhancement and location of enhancement of the optic nerve and distribution of the white matter lesions. RESULTS: Fifty patients met the inclusion criteria. We found an accuracy of 0.98 for the discrimination between AION and ON based solely on parameters extracted from MRI data. Dominance analysis to determine the most influential parameters showed that the enhancement pattern of the optic nerve and distribution of the white matter lesions had the biggest impact on the classification and led to a discrimination accuracy of 0.9 when used alone. CONCLUSION: In patients with an inconclusive clinical diagnosis, optic nerve enhancement pattern and distribution of white matter lesions can aid in the diagnosis and differentiation between AION and ON. Diffusion-weighted imaging did not add significant information to the diagnosis or help to differentiate between the two conditions.

Unilateral corneal arcus and conjunctival vessel alterations in cranial autonomic dysregulation: A case report.

BACKGROUND: Cranial autonomic dysregulation is a common symptom of patients suffering from cluster headache or migraine. The peripheral vascular dysfunction may increase the risk for ischemic or hemorrhagic strokes, myocardial infarction, retinal vasculopathy, cardiovascular mortality, and peripheral artery diseases. Furthermore, it may also manifest with ocular symptoms, e.g., increased lacrimation, conjunctival injection, and facial swelling. CASE PRESENTATION: We here report a case of a patient with migraine and ocular signs of a vascular dysregulation that have led to persisting changes of conjunctival vessels and to a corneal arcus. CONCLUSIONS: Autonomic vascular dysregulation may not only cause headaches but also persisting changes of ocular tissues, e.g., conjunctival vessel alterations and a corneal arcus.

Retinal layer segmentation in a cohort of healthy children via optical coherence tomography.

BACKGROUND: High-resolution optical coherence tomography (OCT) allows the detection of macular pathology and involvement of the optic nerve in a wide spectrum of diseases. For the differentiation of diseased and healthy status, normal values of retinal layer segmentation are critical. Yet, normative values mostly cover adult populations with only sparse data for paediatric cohorts. We present data of retinal layer characteristics via OCT in a healthy paediatric cohort. METHODS: This prospective cross-sectional study screened 75 healthy children (male = 42, female = 33, range 4-17 years) without visual problems. OCT was performed with a peripapillary ring and macula scan protocol to determine paediatric normative values for routine parameters (peripapillary retinal nerve fibre layer thickness (pRNFL), total macular volume (TMV), macular retinal thickness (RT)). The macula scan (6mm grid) was segmented using the device-inherent automated segmentation software (Heidelberg Eye Explorer) for retinal layers: RNFL, ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL) in 9 segments each and mean of the 9 segments. RESULTS: We obtained OCT data of 72 children with mean age 12.49 years (standard deviation, SD, 2.18; minimum 3.93). Mean global pRNFL was 102.20 µm (SD 8.24), mean TMV 8.81 mm3 (0.30) and mean RT (all segments) 318.22 µm (10.19). Segmented macular retinal layer thicknesses (mean of all segments) were: RNFL 27.67 µm (2.14), GCL 41.94 µm (2.50), IPL 34.97 µm (2.10), INL 35.18 µm (2.15), OPL 29.06 µm (2.24), ONL 68.35 µm (6.20). CONCLUSION: The OCT is a useful non-invasive imaging technique for the examination of the retina in children with short duration, high imaging resolution and no known adverse effects. Normative values may serve as a comparator for different neuropaediatric disorders and are first presented with this study using an up-to-date and standardized OCT imaging technique.

Diagnosis and classification of optic neuritis.

There is no consensus regarding the classification of optic neuritis, and precise diagnostic criteria are not available. This reality means that the diagnosis of disorders that have optic neuritis as the first manifestation can be challenging. Accurate diagnosis of optic neuritis at presentation can facilitate the timely treatment of individuals with multiple sclerosis, neuromyelitis optica spectrum disorder, or myelin oligodendrocyte glycoprotein antibody-associated disease. Epidemiological data show that, cumulatively, optic neuritis is most frequently caused by many conditions other than multiple sclerosis. Worldwide, the cause and management of optic neuritis varies with geographical location, treatment availability, and ethnic background. We have developed diagnostic criteria for optic neuritis and a classification of optic neuritis subgroups. Our diagnostic criteria are based on clinical features that permit a diagnosis of possible optic neuritis; further paraclinical tests, utilising brain, orbital, and retinal imaging, together with antibody and other protein biomarker data, can lead to a diagnosis of definite optic neuritis. Paraclinical tests can also be applied retrospectively on stored samples and historical brain or retinal scans, which will be useful for future validation studies. Our criteria have the potential to reduce the risk of misdiagnosis, provide information on optic neuritis disease course that can guide future treatment trial design, and enable physicians to judge the likelihood of a need for long-term pharmacological management, which might differ according to optic neuritis subgroups.

Evaluation of the Reddesa Chart, a New Red Desaturation Testing Method, for Optic Neuritis Screening and Grading in Clinical Routine.

Background: Optic neuritis usually leads to reduced color sensitivity. Most often, the change of red color, the so-called red desaturation, is tested in clinical routine. The aim of this study was to test the feasibility of the Reddesa chart, a new red desaturation test based on polarization, as a screening method for optic neuropathy. Methods: A total of 20 patients with unilateral optic neuritis and 20 healthy controls were included in this prospective pilot study. Ophthalmological examination included assessment of best corrected visual acuity (BCVA), slit lamp examination, fundoscopy, testing of relative afferent pupillary defect (RAPD) and red desaturation with the red cup test and the Reddesa chart. Results: The mean BCVA in the optic neuritis group was 0.76 ± 0.36 in the affected eye (95% of eyes with RAPD, 75% of eyes with difference in the Reddesa test) and 1.28 ± 0.24 in the healthy eye, whereas in the control group, BCVA was 1.14 ± 0.11 in the right eye and 1.15 ± 0.14 in the left eye (none of the eyes with RAPD or abnormal Reddesa test). In our study, the Reddesa test showed a positive predictive value of 100% and a negative predictive value of 80% for detecting optic neuritis. Conclusion: The Reddesa chart allows to quantify red desaturation and has the potential to be implemented as a screening test in clinical routine.

Pharmacological and Behavioral Strategies to Improve Vision in Acquired Pendular Nystagmus.

BACKGROUND Acquired pendular nystagmus (APN) is a back and forth, oscillatory eye movement in which the 2 oppositely directed slow phases have similar waveforms. APN occurs commonly in multiple sclerosis and causes a disabling oscillopsia that impairs vision. Previous studies have proven that symptomatic therapy with gabapentin or memantine can reduce the nystagmus amplitude or frequency. However, the effect of these medications on visual acuity (VA) is less known and to our knowledge the impact of non-pharmacological strategies such as blinking on VA has not been reported. This is a single observational study without controls (Class IV) and is meant to suggest a future strategy for study of vision in patients with disabling nystagmus and impaired vision. CASE REPORT A 49-year-old woman with primary progressive multiple sclerosis with spastic paraparesis and a history of optic atrophy presented with asymmetrical binocular APN and bothersome oscillopsia. We found that in the eye with greater APN her visual acuity improved by 1 line (from 0.063 to 0.08 decimals) immediately after blinking. During treatment with memantine, her VA without blinking increased by 2 lines, from 0.063 to 0.12, but improved even more (from 0.12 to 0.16) after blinking. In the contralateral eye with a barely visible nystagmus, VA was reduced by 1 line briefly (~500 ms) after blinking. CONCLUSIONS In a patient with APN, blinking transiently improved vision. The combination of pharmacological treatment with memantine and the blinking strategy may induce better VA and less oscillopsia than either alone.

No optical coherence tomography changes in premanifest Huntington's disease mutation carriers far from disease onset.

BACKGROUND: Spectral-domain optical coherence tomography (OCT) may detect retinal changes as a biomarker in neurodegenerative diseases like manifest Huntington's disease (HD). We investigate macular retinal layer thicknesses in a premanifest HD (pre-HD) cohort and healthy controls (HC). METHODS: Pre-HD mutation carriers underwent standardized ratings and a preset macular OCT scan. Thickness values were determined for each sector of all macular retinal layers, the mean of all sectors and the mean of the inner ring (IR, 3 mm) after segmentation (Heyex segmentation batch). HC were retrospectively included from an existing database. The IR thickness of the ganglion cell layer (GCL), retinal nerve fiber layer (RNFL), GCL + inner plexiform layer (GCIPL), and total retina were included in the exploratory correlation analyses with paraclinical ratings and compared to HC. RESULTS: The analyses comprised n = 24 pre-HD participants (n = 10 male, n = 14 female) and n = 38 HC (n = 14 male, n = 24 female). Retinal layer parameters did not correlate with paraclinical ratings. Expected correlations between established HD biomarkers were robust. The IR thicknesses of the GCL, GCIPL, and total retina did not differ between pre-HD and HC. The IR thickness of the RNFL was significantly higher in pre-HD participants (pre-HD: 23.22 µm (standard deviation 2.91), HC: 21.26 µm (1.90), p = .002). DISCUSSION: In this cross-sectional cohort of genetically determined pre-HD participants, neurodegenerative features were not detected with retinal layer segmentation. Since our pre-HD collective was more than 16 years before disease onset, OCT may not be sensitive enough to detect early changes.

Antineonatal Fc Receptor Antibody Treatment Ameliorates MOG-IgG-Associated Experimental Autoimmune Encephalomyelitis.

BACKGROUND AND OBJECTIVES: Myelin oligodendrocyte glycoprotein antibody-associated disorder (MOGAD) is a rare, autoimmune demyelinating CNS disorder, distinct from multiple sclerosis and neuromyelitis optica spectrum disorder. Characterized by pathogenic immunoglobulin G (IgG) antibodies against MOG, a potential treatment strategy for MOGAD is to reduce circulating IgG levels, e.g., by interference with the IgG recycling pathway mediated by the neonatal Fc receptor (FcRn). Although the optic nerve is often detrimentally involved in MOGAD, the effect of FcRn blockade on the visual pathway has not been assessed. Our objective was to investigate effects of a monoclonal anti-FcRn antibody in murine MOG-IgG-associated experimental autoimmune encephalomyelitis (EAE). METHODS: We induced active MOG35-55 EAE in C57Bl/6 mice followed by the application of a monoclonal MOG-IgG (8-18C5) 10 days postimmunization (dpi). Animals were treated with either a specific monoclonal antibody against FcRn (α-FcRn, 4470) or an isotype-matched control IgG on 7, 10, and 13 dpi. Neurologic disability was scored daily on a 10-point scale. Visual acuity was assessed by optomotor reflex. Histopathologic hallmarks of disease were assessed in the spinal cord, optic nerve, and retina. Immune cell infiltration was visualized by immunohistochemistry, demyelination by Luxol fast blue staining and complement deposition and number of retinal ganglion cells by immunofluorescence. RESULTS: In MOG-IgG-augmented MOG35-55 EAE, anti-FcRn treatment significantly attenuated neurologic disability over the course of disease (mean area under the curve and 95% confidence intervals (CIs): α-FcRn [n = 27], 46.02 [37.89-54.15]; isotype IgG [n = 24], 66.75 [59.54-73.96], 3 independent experiments), correlating with reduced amounts of demyelination and macrophage infiltration into the spinal cord. T- and B-cell infiltration and complement deposition remained unchanged. Compared with isotype, anti-FcRn treatment prevented reduction of visual acuity over the course of disease (median cycles/degree and interquartile range: α-FcRn [n = 16], 0.50 [0.48-0.55] to 0.50 [0.48-0.58]; isotype IgG [n = 17], 0.50 [0.49-0.54] to 0.45 [0.39-0.51]). DISCUSSION: We show preserved optomotor response and ameliorated course of disease after anti-FcRn treatment in an experimental model using a monoclonal MOG-IgG to mimic MOGAD. Selectively targeting FcRn might represent a promising therapeutic approach in MOGAD.

Effects of Acetyl-DL-Leucine on Ataxia and Downbeat-Nystagmus in Six Patients With Ataxia Telangiectasia.

BACKGROUND: There is no authorized treatment for ataxia telangiectasia (AT). As cerebellar symptoms of storage diseases were improved by acetyl-DL-leucine (ADLL), the authors hypothesized a symptomatic and disease-modifying effect in AT upon supplementation with ADLL. METHODS: Six patients were treated with ADLL 3 g/day for 1 week followed by 5g/day for 3 weeks to 1 year. Cerebellar ataxia was evaluated by validated scales. Gaze-holding, saccades and smooth pursuit were examined by video-oculography. Measurements took place at baseline, at 1 month of therapy in 5 patients, and after 6 and 12 months in 1 patient. RESULTS: The Scale for Assessment and Rating of Ataxia changed from the baseline, mean, (SD, min-max) of 22.1 (5.88, 11-28.5) to 18 points (5.39, 8.5-23.5) after 1 month on medication (P = .0028). All patients demonstrated gaze-holding deficits; 3 patients had central-position downbeat-nystagmus. Mean slow-phase velocity of this nystagmus with the gaze straight-ahead changed from 5.57°/s (1.8, 3.53-6.99) to 4.7°/s (0.79, 3.97-5.56) after 1 month on treatment (1.35, -2.56-4.17) (P = .046). INTERPRETATION: ADLL may improve ataxia and ocular stability in AT patients, while the molecular basis still remains to be elucidated. A multicentric, rater-blinded, phase II trial currently investigates the effects of acetyl-L-leucine in AT (NCT03759678).

Automated alternate cover test for 'HINTS' assessment: a validation study.

OBJECTIVE: The alternate cover test (ACT) in patients with acute vestibular syndrome is part of the 'HINTS' battery test. Although quantitative, the ACT is highly dependent on the examiner's experience and could theoretically vary greatly between examiners. In this study, we sought to validate an automated video-oculography (VOG) system based on eye tracking and dedicated glasses. METHODS: We artificially induced a vertical strabismus to simulate a skew deviation on ten healthy subjects, aged from 26 to 66, using different press-on Fresnel prisms on one eye while recording eye position with VOG of the contralateral eye. We then compared the system's performance to that of a blinded trained orthoptist using conventional, semi-quantitative method of skew measurement known as the alternate prism cover test (APCT) as a gold standard. RESULTS: We found a significant correlation between the reference APCT and the Skew VOG (Pearson's R2 = 0.606, p < 0.05). There was a good agreement between the two tests (intraclass correlation coefficient 0.852, 95 CI 0.728-0.917, p < 0.001). The overall accuracy of the VOG was estimated at 80.53% with an error rate of 19.46%. There was no significant difference in VOG skew estimations compared with the gold standard except for very small skews. CONCLUSIONS: VOG offers an objective and quantitative skew measurement and proved to be accurate in measuring vertical eye misalignment compared to the ACT with prisms. Precision was moderate, which mandates a sufficient number of tests per subject.

Casper Versus Precise Stent for the Treatment of Patients with Idiopathic Intracranial Hypertension.

PURPOSE: We hypothesized that due to its specific characteristics, the CasperTM RX carotid stent (CP) might be particularly suitable for venous sinus stenting (VSS) in patients with idiopathic intracranial hypertension (IIH). To test this theory, we compared it to the commonly used Precise Pro RXTM stent (PP). METHODS: A total of 15 patients with IIH (median age 28.7 years) were reviewed retrospectively. Technical aspects as well as peri- and postinterventional complication rates were examined in patients treated with CP (n = 10) and the PP (n = 5). Improvements in cerebrospinal fluid opening pressure (CSF OP), transstenotic pressure gradient (TSPG) and clinical symptoms were also assessed. RESULTS: Stent delivery was easier and more successful with the CP than the PP (difficult/failed stent delivery 0.0% versus 57.1%) and consequently achieved with less attempts (≥ 2: 0.0% versus 40.0%). No severe peri- or postinterventional complications or instances of in-stent thrombosis and/or stenosis were observed during follow-up. Improvement of CSF OP and TSPG immediately after VSS as well as at 6­month follow-up was comparable between the CP and PP group. Both groups showed substantial and similar decreases in intensity and frequency of headache. Almost all patients with other IIH-related symptoms showed either improvement or complete resolution of those symptoms after VSS. All patients who were available for interview (n = 12/15) reported a substantial improvement in quality of life. CONCLUSION: VSS using the CP seems to be safe and effective. The CP may reduce the risk of difficult or failed stent delivery in patients with challenging intracranial venous anatomy.

Differences in morphology and visual function of myelin oligodendrocyte glycoprotein antibody and multiple sclerosis associated optic neuritis.

BACKGROUND: Myelin oligodendrocyte glycoprotein immunoglobulin G associated optic neuritis (MOG-ON) is a recently described entity. Recent studies have shown that MOG-ON has a more severe clinical presentation than classic optic neuritis (ON). OBJECTIVE: This study aimed to define morphological characteristics of MOG-ON, correlate these with clinical characteristics and compare them with multiple sclerosis associated ON (MS-ON) and healthy controls (CTRL). METHODS: In a retrospective study, we included MOG-ON and MS-ON patients seen between 2011 and 2018 at the University Hospital Bern. Data from clinical examination, perimetry, and optical coherence tomography (OCT) were analyzed. RESULTS: A total of 66 eyes of 43 patients were included; 22 MS-ON and 33 CTRL eyes were sex- and age-matched to 11 MOG-ON eyes. We found significantly worse visual acuity at nadir, but better recovery and thinner global peripapillary retinal nerve fiber layer thickness in MOG-ON patients compared to MS-ON patients. Both groups exhibited irregular thinning of the macular ganglion cell layer. Furthermore, the visual acuity and visual field parameters correlated to retinal layer thickness only in MOG-ON eyes. CONCLUSION: In comparison to MS-ON, MOG-ON is associated with more prominent acute vision loss and more pronounced global thinning of the pRNFL. Both entities result in similar final visual acuity and atrophy of the macular ganglion cell layer.

Evaluation of diagnostic criteria and red flags of myelin oligodendrocyte glycoprotein encephalomyelitis in a clinical routine cohort.

AIMS: Myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) have been proposed to define "MOG encephalomyelitis" (MOG-EM), with published diagnostic and "red flag" criteria. We aimed to evaluate these criteria in a routine clinical setting. METHODS: We retrospectively analyzed patients with borderline/positive MOG-IgG and applied the diagnostic and red flag criteria to determine likelihood of MOG-EM diagnosis. Para-/clinical parameters were described and analyzed with chi-square test. RESULTS: In total, 37 patients fulfilled MOG-EM diagnostic criteria (female-to-male ratio: 1.6:1, median onset age: 28.0 years [IQR 18.5-40.5], n = 8 with pediatric onset). In 24/37, red flags were present, predominantly MOG-IgG at assay cutoff and/or MRI lesions suggestive of multiple sclerosis (MS). As proposed in the consensus criteria, these patients should rather be described as "possible" MOG-EM. Of these, we classified 13 patients as "unlikely" MOG-EM in the presence of the red flag "borderline MOG-IgG" with negative MOG-IgG retest or coincidence of ≥1 additional red flag. This group mainly consisted of patients diagnosed with MS (n = 11). Frequency of cerebrospinal fluid (CSF-)-specific oligoclonal bands (OCB) is significantly lower in definite vs possible and unlikely MOG-EM (P = .0005). CONCLUSION: Evaluation of diagnostic and red flag criteria, MOG-IgG retesting (incl. change of assay), and CSF-specific OCB are relevant in clinical routine cohorts to differentiate MOG-EM from MS.

Comparative Study Between the SORS and Dynamic Strategy Visual Field Testing Methods on Glaucomatous and Healthy Subjects.

Purpose: To clinically validate the noninferiority of the sequentially optimized reconstruction strategy (SORS) when compared to the dynamic strategy (DS). Methods: SORS is a novel perimetry testing strategy that evaluates a subset of test locations of a visual field (VF) test pattern and estimates the untested locations by linear approximation. When testing fewer locations, SORS has been shown in computer simulations to bring improvements in speed over conventional perimetry tests, while maintaining acquisition at high-quality acquisition. To validate SORS, a prospective clinical study was conducted at the Department of Ophthalmology of Bern University Hospital, over 12 months. Eighty-three subjects (32 healthy and 51 glaucoma patients with early to moderate visual field loss) of 114 participants were included in the study. The subjects underwent perimetry tests on an Octopus 900 (Haag-Streit, Köniz, Switzerland) using the G pattern with both DS and SORS. The acquired sensitivity thresholds (ST) by both tests were analyzed and compared. Results: DS-acquired VFs were used as a reference. High correlations between individual STs (r ≥ 0.74), as well as between mean defect values (r ≥ 0.88) given by DS and SORS were obtained. The mean absolute error of SORS was under 3 dB with a 70% reduction in acquisition time. SORS overestimated healthy VFs while slightly underestimating glaucomatous VFs. Qualitatively, SORS acquisition yielded VF with detectable defect patterns, albeit some isolated and small defects were occasionally missed. Conclusions: This clinical study showed that for healthy and glaucomatous patients, SORS-acquired VFs sufficiently correlated with the DS-acquired VFs with up to 70% reduction in acquisition time. Translational Relevance: This clinical study suggests that the novel perimetry strategy SORS could be used in routine clinical practice with comparable utility to the current standard DS, whereby providing a shorter and more comfortable perimetry experience.

Homonymous hemiatrophy of ganglion cell layer from retrochiasmal lesions in the visual pathway.

OBJECTIVE: To determine the temporal evolution, morphology, and frequency of macular ganglion cell atrophy in patients with retrochiasmal lesions of the visual pathway. METHODS: In a consecutive retrospective case series, we identified 47 patients with homonymous hemianopia and accessible macular optical coherence tomography scans. We estimated the time of lesion onset and the location of the lesion within the afferent visual pathway. Using semiautomatic layer segmentation, we determined ganglion cell layer thickness in areas projecting to the side of the retrochiasmal lesion and compared it with ganglion cell layer thickness on the healthy side. RESULTS: We found that retrochiasmal lesions at any level may be associated with an atrophy of ganglion cells. This atrophy respects the vertical midline through the fovea and thus the anatomic separation of the nasal and temporal visual field. The vertical line separating the affected from the unaffected side has significantly less tilt as compared with the disc-fovea angle. Lesions of the optic tract are associated with earlier macular ganglion cell atrophy than retrogeniculate lesions. Macular ganglion cell atrophy may be present in cases with normal peripapillary nerve fiber layer analysis and vice versa. CONCLUSIONS: Macular ganglion cell layer thickness shows a topographic hemiatrophy in retrochiasmal lesions, which manifests earlier for tract lesions than for retrogeniculate lesions. This additional examination of ganglion cell homonymous hemiatrophy has a higher sensitivity in detecting retrograde transsynaptic degeneration than the analysis of the peripapillary nerve fiber layer alone.

Patient-attentive sequential strategy for perimetry-based visual field acquisition.

Perimetry is a non-invasive clinical psychometric examination used for diagnosing ophthalmic and neurological conditions. At its core, perimetry relies on a subject pressing a button whenever they see a visual stimulus within their field of view. This sequential process then yields a 2D visual field image that is critical for clinical use. Perimetry is painfully slow however, with examinations lasting 7-8 minutes per eye. Maintaining high levels of concentration during that time is exhausting for the patient and negatively affects the acquired visual field. We introduce PASS, a novel perimetry testing strategy, based on reinforcement learning, that requires fewer locations in order to effectively estimate 2D visual fields. PASS uses a selection policy that determines what locations should be tested in order to reconstruct the complete visual field as accurately as possible, and then separately reconstructs the visual field from sparse observations. Furthermore, PASS is patient-specific and non-greedy. It adaptively selects what locations to query based on the patient's answers to previous queries, and the locations are jointly selected to maximize the quality of the final reconstruction. In our experiments, we show that PASS outperforms state-of-the-art methods, leading to more accurate reconstructions while reducing between 30% and 70% the duration of the patient examination.

PATIENTS WITH EPIRETINAL MEMBRANES DISPLAY RETROGRADE MACULOPATHY AFTER SURGICAL PEELING OF THE INTERNAL LIMITING MEMBRANE.

PURPOSE: Intraretinal cystoid spaces are commonly found after surgical peeling of epiretinal membranes. In this study, we explored whether these cysts were associated with ganglion cell loss and thus might be a manifestation of retrograde maculopathy. The latter is a nonvascular edema with a characteristic morphology that is often found in the inner nuclear layer (INL) of patients with optic neuropathy. METHODS: In this retrospective case series, we identified consecutive patients who underwent surgical epiretinal membrane peeling. We determined the frequency of microcystic macular edema (MME), defined by vertical cystoid spaces in the INL, and we measured the thickness of individual macular layers before and after surgery. RESULTS: Epiretinal membrane peeling resulted in an improvement of visual acuity and a reduction of retinal thickness by about 15%. In total, 35% of patients with MME before surgery showed no sign of MME postoperatively, whereas edema persisted after surgery in 65% of patients. Interestingly, 29% of the patients without MME before surgery developed MME after surgery. Overall, we found MME in 35% of patients before peeling and in 42% after peeling. After surgery, the mean ganglion cell layer thickness was reduced compared with healthy control eyes. Ganglion cell layer thickness correlated inversely with thickness of the INL. Compared with patients without MME, individuals with MME had a thinner ganglion cell layer and a thicker INL in the affected eye. CONCLUSION: Our findings indicate that peeling of epiretinal membranes and internal limiting membranes is associated with atrophy of ganglion cells and thickening of the INL. The latter is associated with the presence of MME. Altogether, we assume that surgical treatment of epiretinal membranes induces a variant of a retrograde maculopathy.