Documenta Ophthalmologica最新文献

Purpose: To investigate the reproducibility of hand-held full-field electroretinogram (ERG) to determine the minimum change required in longitudinal measurements to reach statistical significance.

Methods: The study included 27 healthy volunteers, aged 45-65. Light-adapted (ISCEV standard) full-field ERGs measured with the RETeval device (LKC Technologies, Germantown, MD, USA) were recorded using non-invasive skin electrodes, followed by a second examination 1-14 days later. Intersession variability of the a- and b-waves, the flicker responses (light intensity 85 Td·s, frequency 28.3 Hz) and the photopic negative response (PhNR, 38 Td·s on 380 Td blue) were assessed.

Results: The mean standard deviations were 0.86, 0.83, 0.40 and 3.24 ms for a-wave, b-wave, flicker and PhNR peak times, respectively. Coefficient of variations (CV) were 32%, 22%, 18%, and 19.2% for the amplitudes of the a-wave, b-wave, flicker and PhNR, respectively.

Conclusion: While flicker ERGs had the smallest variability, ISCEV standard a-wave and b-wave times also had variability less than 1 ms, indicating excellent reproducibility. Amplitudes were more variable, with the a-wave amplitude having the most variability. While it depends on disease, longitudinal studies utilizing ERG timing are expected to be more likely to show statistically significant results due to low inter-session variability.

Purpose: The purpose of this study was to evaluate the effect of repeat testing on N1 and P1 amplitudes, signal-to-noise (SNR) ratios, and amplitude ring ratios (RR) in multifocal electroretinography (mfERG).

Methods: This was a retrospective review of mfERG records from 08/2022 to 05/2023. Patients were tested binocularly with the Espion system (Diagnosys LLC). Only records from patients with repeat mfERG tests at the same appointment were included. N1 and P1 amplitudes, signal-to-noise ratio (SNR), and amplitude ring ratios were evaluated for the first recording (run #1), the second recording (run #2), and the combination of run #1 and run #2 (combined run).

Results: Data was collected for 93 eyes from 47 patients (5 males, 42 females) with a mean patient age of 56.1 ± 17.3 years. No change was observed between run #1 and run #2 for N1 or P1 amplitudes, however amplitudes of the combined run decreased significantly (p  <  0.05) compared to run #1 amplitudes for all rings, right and left eyes (except for ring 1 in right eyes). SNR increased significantly from run #1 to run #2 for rings 2-5 (~10%), but not for ring 1. The number of blinks recorded during testing decreased from run #1 to run #2 (p < 0.001). Amplitude ring ratios R5/R4 and R5/R3 did not change significantly from run #1 to run #2, while amplitude R1/R2 ratio decreased significantly (p < 0.05).

Conclusion: The change in signal quality from run #1 to run #2 suggests a superior quality signal in the second run. Furthermore, the decreased P1 amplitude in the combined run compared to run #1 should be considered when a clinician uses the combined run for their final report.

Purpose: Pupillometry is most commonly performed in laboratory settings using specialized, non-portable instruments that require lengthy test protocols. The purpose of this study was to develop and evaluate a rapid, clinically-applicable pupillometry protocol using a commercially available, portable, handheld instrument.

Methods: Thirty-seven healthy individuals (ages 21-61 years) participated in three experiments. In each experiment, the pupillary light reflex (PLR) was elicited by full-field, 500 ms chromatic flashes (470 nm and 621 nm; 12,000 Td). Experiment I evaluated the minimum dark adaptation (DA) time needed to achieve maximum PLRs. Experiment II determined the effect of age. Experiment III estimated PLR test-retest repeatability. For all experiments, baseline pupil size (BL; 1 s before flash onset), maximum pupil constriction (MPC) following the flash, and post-illumination pupillary response (PIPR; median size 6-8 s after flash offset) were quantified.

Results: Experiment I showed that from 1 to 3 min of DA, BL and MPC increased slightly (0.27 mm and 5%, respectively), whereas the PIPR increased considerably (17%). The responses did not change appreciably after 3 min, therefore a 3 min DA period was used for Experiments II and III. Experiment II showed a trend for BL and MPC to decrease with age, but correlations with age were not statistically significant (all p > 0.05). PIPR was independent of age (r = - 0.01; p = 0.96). Experiment III showed test-retest repeatability of approximately 1 mm for BL, and 10% for MPC and PIPR, indicating good repeatability.

Conclusion: The proposed approach is useful for measuring the MPC and PIPR across a broad range of ages and baseline pupil sizes. Given the device portability and short test duration (approximately 5 min including DA), this approach has promising clinical utility.

Purpose: To report a series of Asian patients with unilateral pigmentary retinopathy.

Methods: Retrospective case series. Clinical features, fundus photography, fundus autofluorescence imaging (FAF), visual fields, optical coherence tomography (OCT) and electrophysiology were reviewed in 6 patients referred to two Singaporean inherited retinal disease clinics with suspected "unilateral retinitis pigmentosa".

Results: Four patients presented with unilateral blurring of vision; 2 were asymptomatic. All index eyes and one fellow eye had FAF abnormalities consistent with visible fundus abnormalities. Visual fields were abnormal in all index and 2 fellow eyes. Macular OCT showed disruption of outer retinal layers in all index eyes and 1 fellow eye. Five index eyes had abnormal rod and cone full field electroretinogram (ERG) amplitudes, while one index eye had localized rod ERG amplitude abnormality. Two index eyes had 30 Hz flicker peak time delay. Three index eyes displayed cone greater than rod system involvement. Pattern electroretinography (PERG) demonstrated macular dysfunction in 5 index eyes and 2 fellow eyes. One case was diagnosed with possible RP. Alternative diagnoses (trauma and autoimmune retinopathy) were ascertained in 4 cases.

Conclusion: Electrophysiology was more sensitive than clinical examination and imaging in detecting retinopathy or maculopathy. In only 1 of 6 patients referred for possible unilateral RP was that diagnosis sustainable; four could be attributed to an identified acquired etiology. Although the diagnosis was unclear in the remaining case, the clinical findings and investigations were not compatible with an inherited disorder.

Purpose: The aim of this study was to investigate whether Posner-Schlossman Syndrome (PSS), is strictly unilateral, to determine the presence of subclinical abnormalities in the contralateral eye, and to analyze the relationship between retinal function and the corneal sub-basal nerve in such patients.

Methods: The patients included in this study were diagnosed with PSS. 14 patients with PSS and 21 healthy controls were recruited for this study. Both eyes of the patients and one eye of the healthy controls underwent full-field electroretinography (ffERG) examination. Additionally, in vivo confocal microscopy (IVCM) was performed on the affected eyes of the patients to assess the status of their corneal sub-basal nerve.

Results: Compared with healthy controls, patients with PSS exhibited significantly reduced amplitudes and abnormal peak times in dark-adapted oscillatory potentials, light-adapted 3 ERG, and light-adapted 30 Hz flicker ERG in both eyes. However, no statistically significant differences were observed in dark-adapted 0.01 ERG, dark-adapted 3.0 ERG, and dark-adapted 10.0 ERG. All ffERG parameters in the affected eyes of patients showed no significant correlations with the total nerve length of corneal sub-basal nerve.

Conclusions: The results demonstrate that PSS is not a strictly unilateral disease. Through ffERG, it is possible to identify cases of bilateral involvement that are difficult to detect, thereby enabling early intervention against potential disease progression.

Purpose: To assess functional and anatomical impairments in pediatric patients and their affected adult family members with juvenile-onset Best vitelliform macular dystrophy (BVMD).

Methods: Fifteen genetically confirmed BVMD patients (10 pediatric and 5 adults) underwent a comprehensive ophthalmic examination with multimodal imaging and electrophysiological testing. We quantified BVMD lesion volumes using sequential spectral-domain OCT (SD-OCT) scans, facilitating correlation with clinical parameters and electroretinogram (ERG) findings.

Results: Children presented less advanced stages of BVMD than adults, had better visual acuity [Log MAR 0.13 ± 0.17] than adults [Log MAR 0.91 ± 0.52, p < 0.001], and displayed lower lesion volumes [0.93 ± 0.71 mm³] compared to adults [1.80 ± 0.79 mm³, p < 0.001]. Interestingly, in 3 eyes in Stage 3 disease (pseudohypopyon stage), despite a high lesion volume (1.74 ± 0.66 mm³), a good visual acuity was still observed (LogMAR of 0.00 in all 3 eyes). Multifocal ERG (mfERG) revealed macular dysfunction in all patients mostly pronounced in the 3 central rings [% of P1 reduction from control in Ring 1 in children and adults: 51% and 51%, Ring 2: 17% and 36% and Ring 3: 8% and 15%, respectively]. Furthermore, higher lesion volumes showed more affected mfERG responses. Full-field flash ERGs were normal in children, while reduced amplitudes and delayed responses were observed in some adults.

Conclusion: While juvenile presentations of BVMD are less severe and more circumscribed, adult presentations demonstrate more widespread functional abnormalities in both amplitude and implicit times correlated with anatomical progression and clinical progression. Interestingly, mfERG responses in children with 20/20 vision also revealed functional impairment, correlating more strongly with the degree of vitelliform liquefaction on OCT than with visual acuity. Our findings suggest that mfERG may serve as an early, reliable indicator of functional defects in BVMD.

Purpose: This study compared the variability of visual evoked potential (VEP) in response to stimulation of eyes affected by unilateral optic neuritis with that of fellow (non-affected) eyes.

Methods: Pattern-reversal VEP (PVEP) and motion-onset VEP (MVEP) recordings from thirty-six subjects with unilateral optic neuritis at different intervals from disease onset were retrospectively evaluated, and differences in the following parameters were compared: signal‒to‒noise ratio (SRN), interquartile range of the response jitter (jitter IQR), and number of trials corresponding to the average response (corresponding N).

Results: In the PVEP recordings, the P1 peak times of the fellow eyes were significantly shorter than those of the affected eyes (Cohen's d = -1.470, p < 0.001). P1 amplitudes were significantly greater in fellow eyes (d = 1.17, p < 0.001). Significant differences were found in the SNR (d = 0.782, p < 0.001), jitter IQR (d = -0.874, p < 0.001), and corresponding N (d = 0.700, p < 0.001). MVEP presented significantly shorter N2 peak times in fellow eyes than in affected eyes (d = 0.840, p < 0.01) and significantly greater amplitudes (d = 0.494, p = 0.002). There was a significant difference in the SNRs (d = 0.440, p = 0.01) and corresponding N values (d = 0.415, p = 0.01). There was no difference in the jitter IQR (d = 0.143, p = 0.230).

Conclusions: The increased variability in eyes affected by optic neuritis compared with fellow eyes (in particular, in pattern-reversal VEP, which predominantly represents the activity of the macular-papillary fibers of the optic nerves) may represent important pathophysiologic features and may add valuable information to diagnostics via VEP examinations.

Purpose: Incomplete congenital stationary night blindness (icCSNB) is a subtype of inherited, non-progressive retinal diseases. Most cases of icCSNB result from mutations in the X-linked gene CACNA1F. We describe the clinical findings of two male siblings diagnosed with icCSNB, both carrying a novel variant c.4008 + 5G > T in CACNA1F inherited from their mother.

Methods: We carried out a comprehensive ophthalmic assessment, including fundus imaging, optical coherence tomography (OCT) scanning and electroretinography. We performed genetic testing with next generation sequencing, in-silico and functional analyses to further characterise the novel variant.

Results: Two male siblings presented with high myopia and reduced visual acuities  at age three. Examination and OCT demonstrated no significant abnormalities in both siblings. Full-field electroretinogram (ffERG) testing demonstrated markedly reduced amplitude to weak flashes and an electronegative waveform to strong flashes in dark-adapted ERGs, resembling that of icCSNB, leading to its diagnosis in both children. Next generation sequencing in the older sibling identified a novel hemizygous c.4008 + 5G > T variant in CACNA1F. In-silico analysis of this variant predicted that it would disrupt normal splicing of CACNA1F, though it was not possible to confirm this by RNA sequencing. This same variant was found in the younger sibling, as well as in their mother who had normal examination and ffERG findings.

Conclusions: We report a novel CACNA1F variant not previously identified in the literature in three patients. Although functional analyses were unable to confirm pathogenicity of this variant, in-silico tools predicted that its effect is consistent with the pathogenesis of icCSNB. Reporting of this family further widens the genotypic spectrum of icCSNB.

Purpose: Quanz et al. (Sci Rep 14:16797, 2024) reported that participants with nystagmus had higher objective visual evoked potential visual acuity estimates (VA_VEP) by 0.12 logMAR relative compared to standard psychophysical VA (VA_{Psych_Stat}). The cause of this modest, but significant VA_VEP overestimation remains unclear. Here we investigated its association with the pattern-pulse stimulation mode applied for steady state VEP recording for VA_VEP estimation. Specifically, we tested whether psychophysical visual acuity to pulsed optotypes (VA_{Psych_Pulsed}) also exceeds standard optotype VA_{Psych_Stat}.

Methods: Twelve participants with nystagmus were included in this analysis. VA_VEP was determined for pattern-pulse steady-state VEP stimulation (Quanz et al. in Sci Rep 14:16797, 2024) using EP2000, psychophysical VA was determined to stationary (VA_{Psych_Stat}) and to pulsed (VA_{Psych_Pulsed}) Landolt-C optotypes employing a modified version of the Freiburg Vision Test (FrACT). Pulsed stimulus timing was identical for VEP and VA (40 ms on and 93 ms off, i.e. at 7.5 Hz). In a separate measurement, fixation stability within the central 4° was determined using microperimetry (Nidek MP-1), and the eye with the stronger fixation instability was selected for the analysis (12 eyes). LogMAR differences were assessed with a paired t-test and the correlation of fixation stability and VA differences (ΔVA_Psych = VA_{Psych_Pulsed} - VA_{Psych_Stat}) was tested.

Results: VA_{Psych_Stat} (0.43 ± 0.06 logMAR) and VA_{Psych_Pulsed} (0.45 ± 0.06 logMAR, P = 0.15) did not differ from each other, but from VA_VEP (0.26 ± 0.08 logMAR, P = 0.02 and P = 0.01, respectively). There was no correlation of ΔVA_Psych with fixation instability (r² = 0.002, P = 0.89).

Conclusion: Pulsed stimulation appears not to be the reason for the VA_VEP overestimation in nystagmus. Further research should address whether differences in the spatial stimulus properties might be of relevance, as VA_Psych is tested with optotypes, VA_VEP with extended patterns.

Background: Foveoschisis refers to the splitting of retinal layers involving the macula that may have different causes with variable structural-functional natural histories. Idiopathic cases are seen in the absence of inherited or acquired predisposing conditions and referred to as stellate nonhereditary idiopathic foveomacular retinoschisis (SNIFR). Our study aimed to clinically and genetically characterize females presenting with foveoschisis (including affected male siblings where present).

Methods: Five patients (3 females and 2 males) from 3 consanguineous families presenting with foveoschisis underwent complete ophthalmological evaluation, multimodal imaging including color, infrared, fundus autofluorescence (FAF), spectral-domain optical coherence tomography (SD-OCT), electroretinogram (ERG), and molecular evaluation including Sanger sequencing of the RS1 gene and whole exome sequencing (WES). Main outcome measures were age at first visit, best-corrected visual acuity (BCVA), peripheral retinal changes, FAF pattern, ERG findings, and RS1 variants.

Results: The mean age was 21.8 years. The BCVA ranged from 20/100 to 20/20. Peripheral retinal changes ranged from a tapetal reflex, peripheral retinoschisis, vitreous veils, to vitreoretinal traction. A ring of increased signal was the most common FAF abnormality, while one patient exhibited a double-ring hyperautofluorescence. All patients demonstrated an electronegative ERG. One female was considered to have a molecularly undiagnosed inherited retinal disease (IRD). Another female was considered stellate nonhereditary idiopathic foveomacular retinoschisis (SNIFR) after exclusion of other causes. Three patients showed a novel nonsense variant in the RS1 gene; homozygous in the female sibling and hemizygous in the male siblings. Familial segregation revealed an unaffected father and a carrier mother. Trio SNP array confirmed maternal segmental uniparental isodisomy (seg UPiD).

Conclusion: This is the first reported X-linked retinoschisis (XLRS) case with seg UPiD. We emphasize the significance of SNP arrays in elucidating non-Mendelian inheritance cases. We report a novel variant, which is the first to be detected in the RS1 domain in a female.