Medical Hypothesis, Discovery & Innovation in Optometry

Abstract

Background: The purpose was to analyze analyze optical coherence tomography (OCT) parameters of choroid and retina in subjects with pre-manifest and manifest Huntington's disease (HD).

Methods: In this cross-sectional observational case-control study, the retinal parameters in HD and healthy controls were evaluated using optical coherence tomography (OCT). Statistical analysis was performed using SPSS 22.0 software package (Statistical Package for the Social Science for Windows, IBM Corp. Replicated 2013. IBM SPSS Statistics for Windows, version 22.0., Armonk, NY: IBM Corp).

Results: A total of 91 subjects, including 60 HD subjects (60 eyes) and 31 control subjects (31 eyes) were eligible based on the inclusion and exclusion criteria. The range of the CAG (cytosine-adenine-guanine) repeat expansion size was 38–56 repeats, the mean ± standard deviation (SD) of the Unified HD Rating Scale (UHDRS) motor scores was 36.3±29.7, and disease duration was 13.7±7.2 years in HD subjects. A significant decrease in the mean ganglion cell complex thickness, as well as mean, temporal, inferior, and nasal retinal nerve fiber layer (RNFL) thickness in HD subjects was revealed in OCT examination compared to the control group (P-values <0,001, <0,001, <0,001, 0.007 and 0.014, respectively). An inverse correlation between the disease duration and the mean RNFL thickness (r=-0.470, P=0.002) was found.

Conclusions: localization of retinal thickness loss shows a specific pattern of retinal neurodegeneration in HD, similar to Parkinson’s disease and mitochondrial diseases. The association with the disease duration confirms the progressive nature of these changes.