Documenta Ophthalmologica最新文献

Purpose: This study explored the clinical value of routine multichannel pattern reversal visual evoked potential (prVEP) recordings in children without nystagmus.

Methods: A single centre, retrospective case note review was carried out of children without nystagmus who had multichannel prVEP recordings from midline, O1 and O2 electrodes referred to Fz to an ISCEV large check (50' check width), reversing 3/s in a full 30° field and right and left 0-15° half fields, during 2020. Full-field (FF) prVEPs were classified as abnormal if midline P100 amplitude and peak time fell outside reference limits. Trans-occipital distribution asymmetry was defined as differences ≥ 20% amplitude between FF-prVEP the O₁ and O₂ at the peak time of the midline P100. Half field (HF) prVEPs acted as the gold standard discriminator of abnormality. The trans-occipital distribution and amplitude of the HF-prVEP ipsilateral positive peak (iP100) were compared for each eye.

Results: FF-prVEP and HF-prVEP data from 63 children were classified. Group 1, 7/63 (11%), had abnormal midline FF-prVEP evidence of visual pathway dysfunction, whilst Group 2, 56/63 (89%), had normal midline FF-prVEPs. Group 2 was subdivided further according to the trans-occipital distribution of FF-prVEPs followed by HF-prVEPs. Group2A, 14/56 (25%), had symmetrical FF-prVEP distribution and normal HF-prVEPs. Group2B, 31/56 (55.4%), had asymmetrical FF-prVEP distribution, but lateralised HF-prVEPs that explained the FF-prVEP asymmetric distribution. Group2C, 11/56 (19.6%), had HF-prVEP evidence of pathway dysfunction with symmetric (n = 2) or asymmetric (n = 9) FF-prVEP distributions. Common referral reasons in all groups were reduced vision, glioma, craniopharyngioma, epilepsy presurgical evaluation, craniosynostosis, papilloedema/disc drusen, with various other specific conditions.

Conclusions: Multichannel prVEPs add value to investigations of reduced or unexplained vision in children without nystagmus. Visual pathway abnormalities would not have been identified without a multichannel FF- or HF-prVEP in 11/56 (19.6%) of children in this study who had normal midline FF-prVEPs.

Purpose: This study aims to evaluate visual function and morphological changes in patients with adrenoleukodystrophy (ALD) through sweep-source optical coherence tomography (SS-OCT) and patterned visual evoked potentials (PVEP), with the goal of providing more accurate and comprehensive data for the diagnosis, monitoring, and assessment of treatment efficacy in patients with ALD.

Methods: This study included 46 ALD patients and 44 healthy controls. The thickness of the retinal nerve fiber layer (RNFL) around the optic disc, as well as the macular RNFL and ganglion cell-inner plexiform layer (GCIPL) thickness, was assessed using SS-OCT. The peak time and amplitude of the P100 wave were also measured using PVEP. Factors that were statistically significant in the univariate analysis were subjected to stepwise binary logistic regression analysis for further investigation. Predictive performance was evaluated by constructing receiver operating characteristic (ROC) curves and compared using DeLong's test.

Results: Compared with the control patients, ALD patients presented a significant increase in the peak time of the P100 wave (P < 0.05); however, no notable difference in amplitude was observed (P > 0.05). Additionally, substantial decreases in the RNFL and GCIPL thicknesses were observed within the parafoveal ring, especially in the superior and nasal quadrants (P < 0.05). The area under the curve for the binary logistic stepwise regression model was 0.883, with a sensitivity of 0.95, which surpassed the performance of the individual parameters.

Conclusion: ALD patients present with abnormal retinal structures and a PVEP peak time delay. Combining these two parameters could increase the accuracy of an early ALD diagnosis.

Purpose: To report our findings in a rare case of vitamin A deficiency (VAD) in a 5-year-old boy who presented with ptosis and exotropia.

Methods: Comprehensive ophthalmological examinations including full-field electroretinography (ff-ERG), optical coherence tomography, and magnetic resonance imaging were performed.

Results: The decimal visual acuity was 0.02 in both eyes at the initial examination. Ophthalmological examinations revealed bilateral corneal opacities, conjunctival keratinization, and exotropia. The scotopic ff-ERGs were extinguished and the photopic ff-ERGs were significantly reduced. Blood tests confirmed severe VAD of ≤ 5 IU/dL (normal range, 97-316 IU/dL). Optical coherence tomography (OCT) showed a thinning of the retinal nerve fiber layer, and MRI suggested a narrowing of the optic nerve canals. A detailed medical history identified autism and a highly selective eating habit limited to white rice. Oral vitamin A supplementation (0.6 g/day) and zinc acetate (25 mg/day) were initiated. Within one month, the corneal epithelial defects had resolved, and the ptosis improved. One year and three months post-treatment, the scotopic and photopic ff-ERGs were markedly improved. However, the OCT and visual evoked potential findings indicated a persistent optic neuropathy.

Conclusions: This case underscores the effect of irreversible optic neuropathy due to delayed VAD diagnosis and treatment in a pediatric patient. An early detailed dietary history, electrophysiological screening, and appropriate supplementation are critical tasks that are needed to lessen the risk of irreversible visual impairment in pediatric VAD cases.

Purpose: To investigate the retinal phenotype and genetic features of a Chinese family with a diagnosis of mitochondrial myopathy and ataxia (MMYAT).

Methods: We conducted a 17-year follow-up of two sisters from a Chinese family and reviewed their medical and family histories. The retinal phenotype was assessed using a multi-modal imaging technique, which includes ultra-widefield (UWF) scanning laser ophthalmoscope (SLO), UWF fundus autofluorescence (FAF), and optical coherence tomography (OCT). Whole exome sequencing (WES) was performed to detect pathogenic variants. Sanger sequencing validation and segregation analysis were further performed for the confirmation of genetic results. A literature review was conducted, analysing the data from 11 published articles encompassing 33 confirmed cases of MMYAT up to 2025.

Results: Ophthalmic multimodal imaging examination revealed typical characteristics of retinal dystrophy in both patients, including binocular widespread salt-and-pepper pigmentation, macular atrophy, a mottled pattern of hypoautofluorescence, and degeneration of the ellipsoid zone. A comprehensive review of the patients' histories identified muscle weakness, ataxia, cerebellar atrophy, mild cognitive impairment, and developmental delay. Two compound heterozygous variants of the mitochondrial distribution and morphology regulator 1 (MSTO1) gene (NM_018116.3), c.971C > T (p.T324I) and c.1108G > A (p.A370P), were detected using WES. A comprehensive literature review was also conducted to gain an overview of the various symptoms associated with MMYAT.

Conclusion: Our study provides a comprehensive ophthalmic characterization of MMYAT, indicating that retinal dystrophy is a key characteristic of this disease. Multimodal imaging of the retina is beneficial for diagnosing MMYAT-associated retinal dystrophy. Increased awareness and comprehensive ophthalmic examination are crucial for obtaining an early and accurate diagnosis.

Purpose: To describe the association between nystagmus characteristics and pattern-reversal VEP (prVEP) P100 amplitude and peak time in patients with albinism.

Methods: We analyzed the prVEP (60' and 15' checksize) and nystagmus recordings from 47 patients with albinism, 17 with a relatively good visual acuity (≤ 0.3 logMAR), and 30 with a relatively poor visual acuity (≥ 0.6 logMAR). The nystagmus waveforms were classified into two types: dominantly pendular and dominantly jerk. We correlated the nystagmus type, amplitude, frequency, and percentage of low velocity (PLOV) to P100 amplitude and peak time.

Results: For most patients (87%), reproducible responses were observed for the large checks (60'). Among patients with good visual acuity, 94% had reproducible responses of which the majority (82%) of P100 amplitudes fell within the normal reference range. In contrast, although 83% of patients with poor visual acuity showed reproducible responses, only a minority (17%) of P100 amplitudes were within the normal range. The P100 amplitude to 60'check sizes was statistically correlated with PLOV (r = 0.58, p < 0.0001), nystagmus type (r = -0.55, p < 0.0001), and nystagmus amplitude (r = -0.39, p = 0.0092). Patients with relatively good visual acuity and jerk nystagmus exhibited the highest PLOV and the largest P100 amplitude (p < 0.0001). In contrast, there was no significant correlation between P100 peak time and any nystagmus parameters in patients with good or poor visual acuity.93% normal peak time. For the small checks (15'), 76% of patients with good visual acuity, still showed reproducible responses, with the majority (71%) of P100 amplitudes falling within the normal reference range. In contrast, among patients with poor visual acuity, only 3% (1 patient) showed reproducible responses, but with amplitudes below the normal range. For the patients with good visual acuity, PLOV showed a significant correlation with P100 amplitude. P100 peak time was normal for 77% (10/13) of these patients.

Conclusions: For the prVEP with 60' checks, nystagmus in patients with albinism predominantly affects the P100 amplitude but not the P100 peak time. For 15' checks the amplitude is often so small that clear responses are no longer discernable, especially in patients with poor visual acuity.

Purpose: To investigate if preterm birth with very low birth weight (VLBW; birth weight < 1500 g) affects macular and visual pathway function in an adult population and explore if best corrected visual acuity (BCVA) was associated with any of the electrophysiologic responses.

Methods: Fifty participants born preterm with VLBW and 77 term-born controls years were recruited when aged 31-41 years from the Helsinki Study of Very Low Birth Weight Adults (Finland) and the NTNU Low Birth Weight Life study (Norway) studies. Pattern reversal electroretinogram (PR-ERG), visual evoked potential (PR-VEP) and BCVA were examined. PR-ERG components (P50, N95 peak time, amplitude and N95:P50 amplitude ratio) and PR-VEP components (N75, P100 and N145 peak time and amplitude) in the better-seeing eye were compared between the groups, and association with BCVA was examined.

Results: The VLBW group showed longer N145 peak time compared to the control group (mean difference 6.8 ms, CI 2.0 to 11.5, p = 0.006) and lower N95:P50 amplitude ratio (CI - 0.3 to - 0.1, p = 0.003). Otherwise, both groups showed similar electrophysiological waveforms. No relationship was found between electrophysiologic responses and BCVA. BCVA was normal in birth groups and showed no group difference.

Conclusion: The responses in the primary visual cortex (N75 and P100) to visual stimuli presented to the better-seeing eye were similar in adults born preterm with VLBW and term-born controls. However, in the VLBW group, there was an indication that subtle electrophysiological deviation may exist at a higher cortical level (N145) and in the ganglion cell response in the macula. These significant differences were not related to reduced visual acuity.

Objective: We present the protocol of a prospective scoping review which aims to understand how multi-channel visual evoked potentials (mcVEPs) are used to investigate congenital chiasmal misrouting and what outcomes are measured, interpreted and reported.

Introduction: mcVEPs are used for the objective evaluation of chiasmal misrouting, which is characterized by a crossed asymmetry in the distribution of cortical responses over each hemisphere during monocular stimulation, and is often observed in patients with albinism. The application and analysis of mcVEPs varies across centers, creating a need to explore the range of practice regarding their conduct and reporting and to identify potential areas for adaptation or optimization or guidelines for specific populations.

Inclusion criteria: Peer reviewed and grey literature on the use of mcVEP to detect chiasmal misrouting in humans with non-acquired pathologies will be considered. All literature providing details of mcVEP methodology for replication and specification of chiasmal misrouting will be included for review.

Methods: Searches will be conducted using MEDLINE, Embase, Cochrane and Web of Science with the expertise of a librarian. The search will be conducted with no limitation on time period, but will be restricted to the Latin alphabet. Titles and abstracts will be screened by two investigators with conflicts resolved by a third investigator. Included articles will proceed with data extraction on study details including methodology, design, and outcomes. The results will be synthesized and mapped for logical understanding.

Purpose: To establish a clinically applicable dark-adapted 15 Hz flicker electroretinogram (ERG) for sensitive detection of functional changes in the fast and the slow retinal rod pathways.

Methods: The study consisted of two parts. In the first part, the paradigm of the previously demonstrated "null-effect" of stimulus luminance on ERG-amplitudes for 15 Hz flicker stimuli with duration of 2.5 s was reexamined. In the second part an optimized faster protocol designed for routine clinical use was tested and compared with the results from the first part and data published in the past. The 15-Hz flicker ERG protocol included 12 steps with different intensities ranging from 0.00019 scot cd.s/m² to 0.05 scot cd.s/m² and was obtained from 15 normally sighted subjects. Stimulus flashes were presented in blue (448 nm) and white, alternating in each luminance step after 20 min of dark adaptation. A shorter version containing only 7 steps was selected with intensities ranging from 0.00031 scot cd.s/m² to 0.005 scot cd.s/m². Additionally, the stimulus paradigm included noise measurement to properly estimate the signal-to-noise ratio.

Results: The results from the first protocol showed a U-shaped amplitude vs. luminance response curve at 15 Hz, consistent with previously published results. Using the new, shortened protocol, we also obtained similar results, but with a much shorter recording time. Based on the signal-to-noise ratio from these measurements a reliable measurement can be obtained in only 2.5 min which presents a considerable time reduction necessary to record a 15 Hz response curve in a clinical setup.

Conclusion: The new protocol is suitable for integration into a daily clinical environment, offering short and well-balanced protocols to address complex retinal network interactions.

Purpose: To assess the repeatability of the multifocal electroretinogram (mfERG) in the 13-lined ground squirrel (13-LGS).

Methods: 13-LGS (Ictidomys tridecemlineatus, 2 M/4F, n = 12 eyes) were equally divided between 61-segment or 103-segment protocols containing two consecutive mfERG scans per session, and two total sessions performed one week apart per eye. The trough-to-peak amplitudes were analyzed under three conditions: raw, normalized to the optic nerve head (ONH), and normalized to the visual streak (VS). For intrasession repeatability, the two consecutive scans within each session were analyzed. For intersession repeatability analyses, one scan was randomly chosen from each day.

Results: Intrasession repeatability of the mfERG trough-to-peak amplitude data averaged at 63% (Raw), 55% (ONH), and 50% (VS). There was no significant difference in repeatability between each day's intrasession repeatability values for all normalization conditions (Raw: Wilcoxon t-test, p = 0.2334; ONH: Paired t-test, p = 0.7803; VS: Wilcoxon t-test, p = 0.3804). Intersession percent repeatability of mfERG trough-to-peak amplitude data averaged at 72% (Raw), 61% (ONH), and 53% (VS). There was a statistically significant difference between the groups (Friedman test, p = 0.0038). This was evident in the Benjamini-Hochberg method of controlling the false discovery rate (FDR) where there was a significant difference comparing Raw versus VS (p = 0.0130) and ONH versus VS (p = 0.0011). There was no difference comparing Raw versus ONH (p = 0.1076).

Conclusions: Overall intrasession and intersession repeatability of mfERG amplitude was relatively poor in our sample, though not markedly different than that reported in some other species and normalization methods did result in improved repeatability. As animal models are critical for vision research, these repeatability estimates will prove useful in interpreting future data collected following interventions or in longitudinal monitoring of disease models.