Documenta Ophthalmologica最新文献

Purpose: To report the early and subsequent electrophysiological findings of 2 patients following quinine overdose.

Methods: Serial assessments including: Medical history, visual acuity (VA), fundus autofluorescence, spectral-domain macular optical coherence tomography (OCT) and full-field electroretinogram (ffERG) were performed on 2 patients, between 2 and 47 days after quinine overdose.

Results: Both patients experienced a similar clinical course. After almost total vision loss within the first 24 h, VA dramatically improved by day 3. Early OCT changes demonstrated central macula hyperautofluorescence, which coincided with a hyperreflectivity of the macular inner retina on OCT. The initial ffERG findings demonstrated changes consistent with marked inner retinal dysfunction of the cone system, affecting both the cone ON- and OFF-bipolar cell pathways. In contrast, rod bipolar cell function was unaffected in the early phase of toxicity. Between days 10 and 17, the retinal arterioles showed narrowing which coincided with attenuation of ffERG parameters of rod system inner retinal function between days 10-40.

Conclusions: These cases suggest the early stages of quinine toxicity affect function of the presynaptic cone bipolar cell junction. This is then followed by retinal arteriolar attenuation and the well described electronegative scotopic ffERG.

Purpose: To compare the pattern electroretinogram (PERG) and patterned visual evoked potential (PVEP) between ocular hypertension (OHT) and normal subjects.

Methods: This cross-sectional observational study included two groups: a control group (46 eyes from 23 subjects; mean age, 33.83 ± 9.10 years old) and an OHT group (34 eyes from 17 patients; mean age, 36.75 ± 11.00 years old). All OHT patients had normal visual fields and normal optic disc appearances but had elevated intraocular pressures. The PERG was recorded using counter-phasing 48' checkerboard patterns, and amplitudes and latencies of P50 and N95 were documented. The PVEP was recorded using checkerboard pattern reversal stimuli with large 60' and small 15' check sizes, and the amplitudes and latencies of the P100 peaks were documented. Group differences were compared, and receiver operating characteristic analyses were performed to evaluate the diagnostic performance of these parameters.

Results: The peak latencies of P50 and N95 in the PERG were significantly prolonged in the OHT group compared to the control group (p = 0.002 and p = 0.041, respectively), while the amplitudes of P50 and N95 were significantly reduced (p < 0.001 for both). Regarding PVEP results, the P100 peak latencies for both 60' check and 15' check stimuli were significantly longer in the OHT group (p < 0.001 for both), and the P100 amplitudes were significantly lower (p = 0.001 and p = 0.017, respectively). Furthermore, the P50 and N95 amplitudes in PERG, and the P100 peak latency in PVEP, all demonstrated good diagnostic ability (AUC > 0.8, p < 0.001).

Conclusion: Abnormalities in PERG and PVEP amplitudes and timing were detected in OHT patients. The P50 and N95 amplitudes in PERG, as well as the P100 peak latency in PVEP, exhibited good ability to differentiate OHT patients from normal subjects.

Background: Neuronal intranuclear inclusion disease (NIID) is a rare autosomal dominant, progressive neurodegenerative disorder characterized by a broad spectrum of clinical conditions, including pyramidal and extrapyramidal symptoms, cerebellar ataxia, cognitive decline and dementia, peripheral neuropathy, and autonomic dysfunction.

Case report: A 56-year-old woman presented night blindness since her youth, followed by tremors. She complained diminished vision in the left eye attributed to the presence of a macular hole. Ophthalmic examination showed obvious retinal degeneration in both eyes. Genetic testing result identified a heterozygous CGG repeat expansion in NOTCH2NLC gene. Visual acuity of left eye improved after vitrectomy.

Conclusions: We reported detailed clinical features and genetic analysis of a new Chinese NIID patient who ocular symptom was the initial manifestation. And this was the first report of surgical case of a macular hole in NIID patient.

Visual evoked potentials (VEPs) are electrophysiologic responses to pattern or flash stimuli, recorded over the occiput. VEPs can provide information regarding the function of the visual system and are valuable in the diagnosis and investigation of optic nerve disease or post-retinal visual pathway dysfunction. The ISCEV VEP Standard specifies stimulus and recording conditions for three basic types of recording: (1) Pattern-reversal VEPs elicited by checkerboard stimuli with large 1° (degree) and small 0.25° check widths. (2) Pattern onset/offset VEPs elicited by checkerboard stimuli with large 1° and small 0.25° check widths. (3) Flash VEPs elicited by a flash which subtends a visual field of at least 20°. The ISCEV VEP Standard protocols are defined for a single recording channel with a midline occipital active electrode. Multi-channel VEPs for evaluation of chiasmal and post-chiasmal lesions, together with protocols specific for pediatric populations, are also described in this document as non-standardized additions. The main changes in the updated ISCEV Standard for clinical VEP include an option to perform a simultaneous pattern electroretinogram (PERG) and pattern-reversal VEP recording, a revised definition of the origin and the analysis of the most prominent VEP components, and more precise descriptions of non-standard multi-channel and pediatric VEP recordings, intended to encourage convergence of widely used non-standard methods. These changes aim to provide a clinically relevant document about current practice which will facilitate good quality recordings and inter-laboratory comparisons.

Purpose: Objective estimation of visual acuity (VA) based on visual evoked potentials (VEPs) has become an established technique for cases where psychophysical VA might be unreliable. Refractive errors and improper accommodation could undesirably affect the outcome of VA measurements. Consequently, it is of interest whether a VA reduction due to dioptric blur is reflected by VEP-based estimation of VA.

Methods: We degraded vision in 19 participants to nearly 1.0 logMAR by using either plus lenses or a filter that creates Gaussian blur. For both types of degradation, we compared the outcomes of objective VEP-based VA testing to standard psychophysical VA. For comparison, we also obtained psychophysical grating VA.

Results: With Gaussian blur, both values, VEP-based VA and psychophysical Landolt-C VA, were nearly identical. With dioptric blur, VEP-based VA was better than psychophysical Landolt-C VA in all participants by an average of 0.37 logMAR with some interindividual variability. Psychophysical grating VA was only relatively mildly affected by blur with no sizable differential effect of blur type.

Conclusion: VEP-based estimation of VA does not reveal the full amount of VA reduction in the case of dioptric blur. On the one hand, this decreases VEP-based methods' susceptibility to incorrect refraction and mis-accommodation, which are not normally the targeted causes of VA reduction. On the other hand, it reduces the accuracy in quantifying refraction-related impairments of vision with VEPs.

Purpose: To study the consequences of a modulating background on the luminance-response function of the human photopic flash electroretinogram for different relative timings of the flash relative to the background luminance.

Methods: Seven healthy subjects (age: 29-63 years; four females) participated in the study. We measured the response to flashes (9 flash strengths in total between 0.12 and 29.76 cd.s/m² while doubling the strength at each step; 5 ms flash duration) on a steady background (24 cd/m²) and on a 1 Hz modulating background (24 cd/m² mean luminance; 100% contrast). The flashes were presented at 6 different phases during the sine wave (0°, 90°, 180°, 225°, 270°, and 315°). Responses to a 1 Hz sinusoidally modulating stimulus were subtracted from the responses to the combined flash plus sine-wave stimuli to obtain the flash ERGs at different phases.

Results: The a-wave and PhNR amplitudes monotonically increased with increasing flash strength. The b- and i-wave amplitudes displayed a maximum at 1.9 cd.s/m², above which they decreased again (the so-called "Photopic hill effect"). The responses could be described by an addition of a logistic growth and a Gaussian. The parameters of these functions depended on the time of flash presentation relative to the background. The dependency of the a-, b- and i-wave on flash presentation time with constant flash strength could be described by a model that assumes that the amplitude depends on the Weber fraction of the flash including a delay and a saturation.

Conclusions: The use of modulating backgrounds may increase the signal-to-noise ratio of flash ERGs and thus its diagnostic value. The dynamics of the response as a function of flash presentation time gives additional information about the retinal processing of flash and background. The photopic hill model allows the separation of processing in retinal On- and Off-pathways.

Purpose: The Celeris system (Diagnosys LLC) offers a streamlined alternative to the gold-standard Espion system for high-throughput electroretinography (ERG) and visual evoked potentials (VEP) in preclinical studies. This study evaluated its inter-session repeatability of ERG and VEP measurements in healthy rodent retinae.

Methods: Twenty-five wild type Brown Norway rats underwent ERG and VEP testing across two sessions. Dark-adapted ERG a- and b-waves (flash stimulus of 10 cd s/m²), and the photopic negative response (PhNR) (flash stimulus of 3 cd s/m²) were recorded. VEPs (flash stimulus of 3 cd s/m²) were recorded from implanted screw electrodes in the skull. Pearson's correlation coefficient (ρ), Bland-Altman with 95% limits of agreement (LOA) and a novel cumulative distribution plot were used to assess inter-session agreement.

Results: Intersession dark-adapted a-wave showed a correlation of ρ = 0.73, (P < 0.0001), LOA: -106.4 to 113.9 µV, and 90% of measurements fell within - 24.8 to 58.0% variation (90% range). Intersession dark-adapted b-wave amplitudes showed ρ = 0.65, (P < 0.001), LOA: - 402.5 to 437.4 µV, and 90% range: - 33.7 to 72.6%. Inter-session PhNR-B (base-to-trough) and PhNR-P (peak-to-trough) amplitudes showed ρ = 0.66 and 0.72 respectively; LOA: - 26.7 to 31.1 µV and - 98.9 to 100.1 µV respectively; 90% ranges: - 58.2 to 59.3%, and - 45.6 to 60.9%, respectively. Inter-session VEP P2 amplitude showed ρ = 0.67, (P < 0.001), LOA: 78.5-72.8 µV, and 90% range: - 52.2 to 67.9%. Inter-session VEP implicit time showed ρ = 0.48, (P < 0.05), LOA: - 39.4 to 38.3 ms, and 90% range: - 39.2% to 16.7%.

Conclusion: The study reported the inter-session repeatability of the ERG and VEP tests using the Celeris system. These data facilitate the study design and sample size calculation for future preclinical studies using the Celeris, and serve as a reference for future comparison with other systems, protocols and species.

Objective: The primary aim of this study was to compare pupillometry measurements obtained from the Sirius™ and AL-Scan™ devices under different lighting conditions. Additionally, the secondary aim was to assess and compare the topographic (keratometric) measurements provided by these systems.

Materials and methods: A non-interventional and prospective study was conducted on normal patients aged 18-45 years. Patients who did not smoke and had a spherical equivalent ranging from + 3.00 D to - 5.0 were included. Pupillometry measurements were taken after 1 minute of dark adaptation. Only the right eyes were compared for keratometry. All eyes were compared for pupillometry. We compared the K1 (D), K2 (D), KAvg (D), photopic pupillometry (PP), and mesopic pupillometry (MP) values.

Results: We examined a total of 30 women (66.7%) and 15 men (33.3%). AL Scan showed an average K1 of 42.99 ± 1.50 D, an average K2 of 44.04 ± 1.74, and an average Kavg of 43.58 ± 1.62. Sirius topography yielded the following averages: 42.94 ± 1.51 for K1, 43.90 ± 1.75 for K2, and 43.41 ± 1.61 for Kavg. The average PP and MP measures obtained with the Nidek Al-Scan instrument were 3.97 ± 1.08 mm and 6.04 ± 1.08 mm, respectively. The Sirus device yielded average PP and MP values of 5.05 ± 1.04 mm and 6.01 ± 1.08 mm, respectively. Bland-Altman statistics showed a good degree of correlation between the MP measurements of both devices (p = 0.65). However, K1, K2, KAvg, and PP data showed no significant agreement between both devices (p < 0.05).

Conclusion: In our research, Sirius and Nidek Al-Scan equipment yield comparable MP data; however, PP is inconsistent. Device selection with repeated pupillometry data requires more investigation.

Purpose: This study aimed to establish a reference data set of light-adapted full-field electroretinograms (ffERG) of healthy primary and secondary schoolchildren and investigate the relationship among refraction, ocular biometry, and ffERG.

Methods: Healthy children aged between 6 and 17 years were recruited. Cycloplegic spherical equivalent refraction (SER), axial length (AL) and keratometry (K) measurements were performed. Standardized ffERGs, including light-adapted flash and 30-Hz flicker, were measured using a portable device with skin electrodes. The percentiles of peak time and amplitude of a- and b-waves and 30-Hz flicker of ffERG waveform were reported, and their relationships with age, SER, AL, K were investigated.

Results: Among the 445 participants (45.4% female), the SER (mean ± standard deviation) was - 0.72 ± 2.06 D and AL was 23.56 ± 1.15 mm. The 90% confidence interval (CI) of 5th reference limit of amplitudes of a- and b-wave were 5.0-5.8 µV and 15.0-17.6 µV, while 95th reference limit of peak times were 13.2-13.4 ms and 29.8-30.0 ms, respectively. The amplitude and peak time of the 30-Hz flicker waveform were 21.5-23.9 µV and 26.0-26.2 ms, respectively. In general, more myopic SER, and longer AL were associated with delayed and reduced ffERG waveforms. Older age and male sex were weakly correlated with ffERGs with minimal clinical significance.

Conclusions: A reference data set of light-adapted ffERG in children and adolescents was established for clinical and research purposes.