Ganglion cell layer-inner plexiform layer thickness and vision loss in cerebral palsy

Abstract

Purpose: To determine if measurements of macular ganglion cell layer-inner plexiform layer (GCLIPL) thickness can discriminate between cerebral palsy patients with and without vision loss using spectral domain optical coherence tomography (SDOCT).
Study design: Cross-sectional.
Materials and methods: Participants with cerebral palsy enrolled in a prospective study of SDOCT were included if they were cooperative for visual acuity (VA) testing and macular SDOCT images were acquired. Manual segmentation of the macular GCLIPL was performed using elliptical annuli with diameters of 4.5 mm. Subjects with VA < 6/9 were defined as having abnormal vision. Mann-Whitney U test was used to evaluate the relationship between vision and macular GCLIPL thickness. Data were analysed using SPSS version 22.0 software.
Results: Forty study eyes (normal vision = 17 eyes; abnormal vision = 23 eyes) from 21 participants with spastic cerebral palsy were included. Most subjects were male (61.90%, n = 13) and the median age was 13 years (range from 7 to 29 years). The median visual acuity was 0.1 logMAR for subjects with normal vision and 0.3 logMAR for subjects with abnormal vision. Eyes with normal vision had higher average GCLIPL thickness (mean = 106.3 ± 27.85 μm) compared to eyes with abnormal vision (mean = 96.6 ± 36.47 μm). However, a significant association between GCLIPL thickness and visual impairment could not be established in this study.
Conclusion: Our study demonstrated a reduction in macular GCLIPL thickness in cerebral palsy patients with visual impairment but did not fully support its use as surrogate marker of cerebral visual impairment due to study limitations. Future longitudinal studies are advised to elucidate the relationship between macular GCLIPL
and cerebral visual impairment.