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Purpose Genome sequencing (GS) is expected to reduce the diagnostic gap in rare disease genetics. We aimed to evaluate a scalable framework for genome-based analyses 'beyond the exome' in regular care of patients with inherited retinal degeneration (IRD) or inherited optic neuropathy (ION). Methods PCR-free short-read GS was performed on 1000 consecutive probands with IRD/ION in routine diagnostics. Complementary whole-blood RNA-sequencing (RNA-seq) was done in a subset of 74 patients. An open-source bioinformatics analysis pipeline was optimised for structural variant (SV) calling and combined RNA/DNA variation interpretation. Results A definite genetic diagnosis was established in 57.4% of cases. For another 16.7%, variants of uncertain significance were identified in known IRD/ION genes, while the underlying genetic cause remained unresolved in 25.9%. SVs or alterations in non-coding genomic regions made up for 12.7% of the observed variants. The RNA-seq studies supported the classification of two unclear variants. Conclusion GS is feasible in clinical practice and reliably identifies causal variants in a substantial proportion of individuals. GS extends the diagnostic yield to rare non-coding variants and enables precise determination of SVs. The added diagnostic value of RNA-seq is limited by low expression levels of the major IRD disease genes in blood. [ABSTRACT FROM AUTHOR]

Background: It is generally believed that optic disc drusen (ODD) change only over long periods of time. Because, in our experience, this does not apply to younger patients, we investigated the natural course of changes of the peripapillary retinal nerve fiber layer (RNFL) in patients with ODD. Methods: In this retrospective study, 40 eyes with and 40 eyes without ODD were examined, both cohorts were equally subdivided into younger subjects (20 years or younger) and older subjects (21 years or older). Three optical coherence tomography (OCT) scans of the peripapillary RNFL that had an interval of at least 1 month were required for each patient to be included in this study. The largest difference in total RNFL thickness (delta RNFL-t) and in RNFL thickness of the most differing sector (delta RNFL max) measured by OCT was compared. Results: The differences in total RNFL thickness and in the most differing RNFL sector in the group of patients with ODD younger than 21 years were significantly larger than in each of the other 3 groups (P = 0.0001). The other 3 groups did not differ significantly. Conclusions: Patients with ODD younger than 21 years have distinct variations in peripapillary RNFL thickness without evidence of increased intracranial pressure. In the absence of further pathological findings or neurological symptoms, an observational approach seems adequate in these patients. [ABSTRACT FROM AUTHOR]

Background/aims To evaluate the PandAcuity test for visual function testing in a paediatric cohort and to examine its agreement with conventional visual acuity (VA) testing. Methods PandAcuity scores were determined in 152 children (77 males) aged between 3 and 15 years after VA testing (LEATM-test, E-chart, Landolt-C-rings or numbers). The PandAcuity test consisted of illusions made up from silhouettes of animals 'hidden' within zig-zag-patterns of decreasing spatial frequencies. Correlation analyses between PandAcuity score and VA were performed. Results 150 children completed the test in at least one eye, 148 in both eyes. The PandAcuity test demonstrated good test-retest reliability (intraclass correlation coefficient=0.89) between two runs. VA and PandAcuity score showed a medium to large correlation (Spearman's ρ=0.52, p<0.0001). 93% of the children's visual impairment was classified in the same range by both test types. Receiver operating characteristic analysis of predicted visual impairment showed an excellent agreement with the classification based on VA testing (AUC=0.84). Conclusion The PandAcuity test is rapid, simple and well accepted, rendering it a suitable supplement for the clinical assessment of VA in children. Because of its counterintuitive application (a higher number of correctly identified images means worse VA), it can be used to cross-validate conventional acuity tests to assure children's compliance. [ABSTRACT FROM AUTHOR]

Background Voretigene neparvovec is a gene therapeutic agent for treatment of retinal dystrophies caused by bi-allelic RPE65 mutations. In this study, we report on a novel and objective evaluation of a retinotopic photoreceptor rescue. Methods Seven eyes of five patients (14, 21, 23, 24, 36 years, 1 male, 4 females) with bi-allelic RPE65 mutations have been treated with voretigene neparvovec. The clinical examinations included visual acuity testing, dark-adapted full-field stimulus threshold (FST), dark-adapted chromatic perimeter (DAC) with a 30-degree grid, and a 30 degrees grid scotopic and photopic chromatic pupil campimetry (CPC). All evaluations and spectral domain optical coherence tomography were performed at baseline, 1 month and 3 months. Results All except the oldest patient had a measurable improvement of the rod function assessed via FST, DAC or scotopic CPC at 1 month. The visual acuity improved slightly or remained stable in all eyes. A cone function improvement as measured by photopic CPC was observed in three eyes. The gain of the dark-adapted threshold with blue FST and the DAC stimuli (cyan) average correlated strongly with age (R2>0.7). The pupil response improvement in the scotopic CPC correlated with the baseline local retinal volume (R2=0.5). Conclusions The presented protocols allow evaluating the individual spatial and temporal effects of gene therapy effects. Additionally, we explored parameters that correlated with the success of the therapy. CPC and DAC present new and fast ways to assess functional changes in retinotopic maps of rod and cone function, measuring complementary aspects of retinal function. [ABSTRACT FROM AUTHOR]

This work presents a quick clinical protocol for dark-adapted chromatic (DAC) perimetry as well as a novel clinical tool, scotopic chromatic pupil campimetry (CPC). The goal of the study was to explore the applicability of these methods in a clinical setting, their test-retest repeatability, and the congruence of the results. Local rod sensitivity was assessed at 36 locations within 30° eccentricity of the visual field in 15 healthy subjects (mean age 43 ± 16 years; 7 females and 8 males) with DAC perimetry (red and cyan stimuli) and CPC 2 times in repeated measurements. The duration of individual measurements was 370 ± 5 s for CPC and 366 ± 62 s for DAC perimetry. The intraclass correlation (ICC) coefficient was 0.53 for DAC perimetry cyan stimuli, 0.67 for red stimuli, and 0.93 for CPC. However, the spatial resolution of CPC was substantially smaller than in DAC perimetry. We did not find a correlation of DAC perimetry and CPC measurements on the global or the local level. In comparison to DAC perimetry, CPC shows a superior intervisit repeatability in detecting functional changes in the rod population in an objective way with lower spatial resolution. Our results also indicate that these 2 methods measure the rod function in different ways and could thus constitute complementary scotopic functional diagnostics. [ABSTRACT FROM AUTHOR]