Documenta Ophthalmologica最新文献

The pattern electroretinogram (PERG) is a localized retinal response evoked by a contrast-reversing pattern, usually a black and white checkerboard, which provides information about macular and retinal ganglion cell function. This document, from the International Society for Clinical Electrophysiology of Vision (ISCEV; www.iscev.org ) presents an updated and revised Standard for clinical PERG testing. This replaces the 2013 and all earlier versions. Minimum protocols for basic PERG stimuli, recording methods and reporting are specified, to promote consistency of methods for diagnosis and monitoring purposes, while responding to evolving clinical practices and technology. The main changes in the updated ISCEV Standard for clinical PERG include expanded guidance about large stimulus fields, stimulus parameters for simultaneous PERG and pattern visual evoked potential recording, baseline drift correction, and use of consistent ambient room lighting. These changes aim to provide a clinically relevant document about current practice which will facilitate good quality recordings and inter-laboratory comparisons.

Purpose: To report our findings of reduced full-field electroretinograms (ff-ERGs) and abnormal optical coherence tomographic (OCT) images in a patient with poor visual acuity after cataract surgery who was eventually diagnosed with vitamin A deficiency (VAD).

Methods: This was a clinical study of a patient who complained of blurred vision after cataract surgery. To determine the cause of the reduced vision, we recorded full-field electroretinograms (ff-ERGs) to determine the scotopic and photopic status of the retina. We also performed optical coherence tomography to assess the changes in the retinal structure. Serological tests were performed.

Results: A 74-year-old man presented with persistent corneal epithelial damages and reduced vision that developed after conventional cataract surgery. OCT showed an interrupted ellipsoid zone, and fundus autofluorescence (FAF) showed a severe hypofluorescence in the retina of the left eye. The scotopic ff-ERGs were severely reduced, and the photopic ff-ERGs were mildly reduced. Serological examinations revealed a vitamin A concentration < 7 IU/dL (normal, 97-316 IU/dL). Based on these findings, we diagnosed the patient with VAD and started treatment with oral vitamin A supplements. After three months, his visual acuity, ff-ERGs, and OCT findings recovered to normal levels. The amplitudes and implicit times of the RETeval flicker ERGs increased to be within the normal range, and the hypofluorescence of the left eye disappeared. The length of the photoreceptor outer segments increased after the vitamin A supplementation.

Conclusion: Our findings indicate that the ERGs are helpful for diagnosing patients with VAD associated with persistent corneal epithelial damages.

Purpose: To correlate multifrequency pattern reversal VEPs in quadrants (QmfrVEPs) with perimetric field losses for objective detection of visual field losses.

Methods: QmfrVEP measurements were performed using four LED-based checkerboard stimulators to stimulate the four quadrants of the visual field. QmfrVEPs were measured monocularly in 5 normal subjects and in 5 glaucoma patients who showed losses in conventional Octopus perimetry. The pattern reversal frequency varied slightly between the stimulators: (11.92, 12.00, 12.08 and 12.16 reversals/sec). The responses to the different stimuli were identified by discrete Fourier analysis. VEPs were recorded using different electrode configurations, and the recording with the highest signal-to-noise ratio (SNR) was used for further analysis.

Results: QmfrVEP responses from the different quadrants can be reliably measured and separated using the 0.08 reversals/sec interstimulus reversal frequency differences. The signal-to-noise ratio in the four quadrants was significantly correlated with the equivalent visual field losses obtained with perimetry (Spearman rank correlation: P < 0.001). In the five glaucoma patients, the SNR was reduced in 15 out of the 16 quadrants with a perimetric defect, in comparison to the results in quadrants of healthy subjects. This confirms the sensitivity of the procedure.

Conclusion: QmfrVEP responses can be measured reliably. This pilot study suggests that high SNR values exclude visual field defects and that focal defects can be identified in glaucoma patients.

Trial registration: www.

Clinicaltrials: gov . NCT00494923.

Purpose: In this study, we report a case of a young adult with X-linked juvenile retinoschisis (XLRS) with a rare pathogenic variant in the RS1 gene (c.522 + 2 T > A).

Methods: Ophthalmological evaluation, optical coherence tomography, full-field and multifocal electroretinograms and extensive genetic screening of genes related to visual loss were carried out in the participant.

Results: Clinical ophthalmological exams revealed a mild to moderate impairment of visual acuity. Retinal imaging showed bilateral foveal schisis, as well as normal a-wave, reduction in the b-wave amplitudes in dark- and light- adapted full-field electroretinograms, and abnormal oscillatory potentials. We found also diffuse amplitude reduction in multifocal electroretinogram arrays. A canonical splice variant was identified in the RS1 gene (c.522 + 2 T > A).

Conclusion: A rare pathogenic variant of the RS1 gene was associated with diffuse retinal involvement (central and peripheral retina), probably in inner retina, and mild to moderate visual acuity impairment. The phenotypical characterization of rare mutations is relevant to provide information about the disease.

Purpose: We report diagnostic and therapeutic dilemmas in the difficult case of compressive optic neuropathy with severe visual acuity and visual field loss with subsequent visual recovery in both eyes, in a patient with Graves' orbitopathy (GO) by a combination of experimental antithymocyte therapy, orbital radiotherapy with high-dose steroids.

Methods: A 72-year-old man presented with severe vision loss in both eyes. The visual symptoms had appeared over a year before the GO diagnosis. He was initially misdiagnosed with neuroborreliosis and optic neuritis based on brain and orbital magnetic resonance imaging. There was no exophthalmos. The ophthalmological examination included visual acuity, visual field, tonometry in primary and upgaze eye position, optical coherence tomography (OCT), pattern electroretinogram (PERG), pattern, and flash visual evoked potentials (PVEP and FVEP). The patient received experimental therapy with ATG, followed by high-dose of intravenous steroids and orbital radiotherapy.

Results: Delayed VEP peaks became shorter after treatment. After systemic and local therapy lowering of intraocular pressure was achieved. Abnormal PERG has been found three months before ganglion cells atrophy was detected in OCT. Visual acuity and visual field improvement occurred in both eyes after therapy, despite partial left optic nerve atrophy. The patient regained full decimal visual acuity (1.0 right from as poor as 0.3  to 1.0 in the right eye and from hand movements to 0.9 in the left. Severe visual field loss with advanced absolute scotomata has improved to slight relative scotomata. The duration of follow-up time after the treatment was 4 months.

Conclusions: Intensive treatment of steroid-resistant Graves' orbitopathy (GO) may prevent total optic nerve atrophy. Despite severely advanced optic neuropathy, this report emphasizes the necessity of therapy even with nearly complete visual function loss hence there is always a possibility to regain full visual acuity and visual field. Patients with tense orbital septum may not present with significant exophthalmos, thus delaying the correct diagnosis of orbitopathy. A supporting sign of GO was the difference in intraocular pressure in the primary and upgaze eye positions. Electrophysiological examinations are helpful in the diagnosis and monitoring of GO therapy. To our knowledge, this is the first report of this kind presenting visual function restoration and structural recovery in a patient with advanced optic neuropathy in GO.

Purpose: Both rod and cone-driven signals contribute to the electroretinogram (ERG) elicited by a standard strong flash in the dark. Negative ERGs usually reflect inner retinal dysfunction. However, in diseases where rod photoreceptor function is selectively lost, a negative waveform might represent the response of the dark-adapted cone system. To investigate the dark-adapted cone-driven waveform in healthy individuals, we delivered flashes on a dim blue background, designed to saturate the rods, but minimally adapt the cones.

Methods: ERGs were recorded, using conductive fibre electrodes, in adults from the TwinsUK cohort. Responses to 13 cd m^-2 s white xenon flashes (similar to the standard DA 10 flash), delivered on a blue background, were analysed. Photopic and scotopic strengths of the background were 1.3 and 30 cd m^-2, respectively; through a dilated pupil, this is expected to largely saturate the rods, but adapt the cones much less than the standard ISCEV background.

Results: Mean (SD) participant age was 62.5 (11.3) years (93% female). ERGs from 203 right and 204 left eyes were included, with mean (SD) b/a ratios of 1.22 (0.28) and 1.18 (0.28), respectively (medians, 1.19 and 1.17). Proportions with negative waveforms were 23 and 26%, respectively. Right and left eye b/a ratios were strongly correlated (correlation coefficient 0.74, p < 0.0001). We found no significant correlation of b/a ratio with age.

Conclusions: Over 20% of eyes showed b/a ratios less than 1, consistent with the notion that dark-adapted cone-driven responses to standard bright flashes can have negative waveforms. The majority had ratios greater than 1. Thus, whilst selective loss of rod function can yield a negative waveform (with reduced a-wave) in some, our findings also suggest that loss of rod function can occur without necessarily yielding a negative ERG. One potential limitation is possible mild cone system adaptation by the background.

Purpose: To report a case series of patients with retinal toxicity due to hydroxychloroquine (HCQ) within a short span of treatment.

Methods: A retrospective review of case records of patients with accelerated HCQ toxicity within 1 year of starting the treatment was done. Systemic co-morbidities, details of HCQ treatment, details of ocular examination, and results of multimodal investigations were noted.

Results: Nine patients (1 male, 8 females) with age ranging from 40 to 73 years (mean 54.2 ± 13.4 years) who showed accelerated HCQ toxicity were included. None had systemic conditions or drug history predisposing to early HCQ toxicity. The treatment duration ranged from 2 to 11 months and the cumulative HCQ dose ranged from 18 to 120 g (mean 45.0 ± 33.0 g). The visual acuity was normal in 8 (88.9%) patients and retinal evaluation was normal in 4 (44.4%). Optical coherence tomography was abnormal in 4 (44.4%). Six (66.6%) cases had reduced sensitivity in the parafoveal point on visual field testing. All 9 cases had multifocal electroretinographic changes diagnostic of HCQ toxicity. The HCQ treatment was stopped in 8 and continued with reduced dose in 1 patient. The mean duration of follow-up was 11.2 ± 9.6 months during which 5 patients showed improved mfERG and 1 patient had a stable mfERG. Visual fields improvement was noted in 2 cases.

Conclusions: Patients on HCQ need to be kept on regular monitoring with more frequent follow-ups to detect signs of early onset toxicity and prevent permanent visual impairment. mfERG is an important diagnostic tool for HCQ toxicity.

Purpose: The purpose of this study was to describe and diagnose the difficulty in a long-term follow-up (eleven years) patient with a very early presentation of late-onset retinal degeneration (L-ORD) and the significance of electrophysiological examinations and follow-up in assessing undiagnosed inherited retinal diseases.

Methods: This is an observational case report of a 56-year-old woman, with scattered multiple yellow-white retinal dots firstly diagnosed as fundus albipunctatus. Ten years after presentation, a deterioration in rod and cone responses in ff-ERG was detected, which allowed us to discard the first diagnostic hypothesis and proceed with a genetic testing.

Results: Ten years after presentation, she presented a clear progression of the abnormal photoreceptor response with a cone and rod involvement in ff-ERG, which was not compatible with the previous suspicion of fundus albipunctatus. Six months later, genetic testing results together with the typical progression of atrophic patchy lesions in multimodal imaging allowed a certain diagnosis of L-ORD, caused by an already reported pathogenic variant in the C1QTNF5 gene (c.563C > T; p. Pro188 Leu).

Conclusions: We demonstrate the importance of the ff-ERG examination and the follow-up (or ERG and imaging repetition) in the differential diagnosis of an incipient L-ORD, which can be easily misdiagnosed in the early stages, before the appearance of the characteristic chorioretinal atrophy seen with the progression of this rare disease.