Abstract
BackgroundSpinocerebellar ataxia type 1 (SCA‐ATXN1) is an inherited progressive ataxia disorder characterized by an adult‐onset cerebellar syndrome combined with nonataxia signs. Retinal or optic nerve affection are not systematically described.ObjectivesTo describe a retinal phenotype and its functional relevance in SCA‐ATXN1.MethodsWe applied optical coherence tomography (OCT) in 20 index cases with SCA‐ATXN1 and 22 healthy controls (HCs), investigating qualitative changes and quantifying the peripapillary retinal nerve fiber layer (pRNFL) thickness and combined ganglion cell and inner plexiform layer (GCIP) volume as markers of optic atrophy and outer retinal layers as markers of maculopathy. Visual function was assessed by high‐ (HC‐VA) and low‐contrast visual acuity (LC‐VA) and the Hardy‐Rand‐Rittler pseudoisochromatic test for color vision.ResultsFive patients (25%) showed distinct maculopathies in the ellipsoid zone (EZ). Furthermore, pRNFL (P < 0.001) and GCIP (P = 0.002) were reduced in patients (pRNFL, 80.86 ± 9.49 μm; GCIP, 1.84 ± 0.16 mm3) compared with HCs (pRNFL, 97.02 ± 8.34 μm; GCIP, 1.98 ± 0.12 mm3). Outer macular layers were similar between groups, but reduced in patients with maculopathies. HC‐VA (P = 0.002) and LC‐VA (P < 0.001) were reduced in patients (HC‐VA [logMAR]: 0.01 ± 010; LC‐VA [logMAR]: 0.44 ± 0.16) compared with HCs (HC‐VA [logMAR]: –0.12 ± 0.08; LC‐VA [logMAR]: 0.25 ± 0.05). Color vision was abnormal in 2 patients with maculopathies.ConclusionsA distinct maculopathy, termed EZ disruption, as well as optic atrophy add to the known nonataxia features in SCA‐ATXN1. Whereas optic atrophy may be understood as part of a widespread neurodegeneration, EZ disruption may be explained by effects of ataxin‐1 gene or protein on photoreceptors. Our findings extend the spectrum of nonataxia signs in SCA‐ATXN1 with potential relevance for diagnosis and monitoring.
Highlights
Spinocerebellar ataxia type 1 (SCA-ataxin 1 gene (ATXN1)) is an inherited progressive ataxia disorder characterized by an adult-onset cerebellar syndrome combined with nonataxia signs
We analyzed group differences in neuroretinal content between eyes from patients with SCA-ATXN1, including those with macular anomalies, and healthy controls (HCs) (Table 3; Fig. 2). peripapillary retinal nerve fiber layer (pRNFL) as the marker of axonal content in SCA-ATXN1 was reduced compared with HCs
high-contrast monocular visual acuity (HC-VA) as well as low-contrast visual acuity (LC-VA) were reduced in patients with SCA-ATXN1 compared with HCs (Table 3; Fig. 2)
Summary
Spinocerebellar ataxia type 1 (SCA-ATXN1) is an inherited progressive ataxia disorder characterized by an adult-onset cerebellar syndrome combined with nonataxia signs. Objectives: To describe a retinal phenotype and its functional relevance in SCA-ATXN1. Methods: We applied optical coherence tomography (OCT) in 20 index cases with SCA-ATXN1 and 22 healthy controls (HCs), investigating qualitative changes and quantifying the peripapillary retinal nerve fiber layer (pRNFL) thickness and combined ganglion cell and inner plexiform layer (GCIP) volume as markers of optic atrophy and outer retinal layers as markers of maculopathy. Outer macular layers were similar between groups, but reduced in patients with maculopathies. Color vision was abnormal in 2 patients with maculopathies. Conclusions: A distinct maculopathy, termed EZ disruption, as well as optic atrophy add to the known nonataxia features in SCA-ATXN1. Our findings extend the spectrum of nonataxia signs in SCA-ATXN1 with potential relevance for diagnosis and monitoring
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
