Nashila Hirji1, Maria Theodorou2, James W Bainbridge1, Nadia Venturi3, Michel Michaelides1. 1. UCL Institute of Ophthalmology, University College London, London, United Kingdom; Moorfields Eye Hospital, London, United Kingdom. 2. UCL Institute of Ophthalmology, University College London, London, United Kingdom; Moorfields Eye Hospital, London, United Kingdom. Electronic address: mtheodorou@nhs.net. 3. Moorfields Eye Hospital, London, United Kingdom.
Abstract
PURPOSE: To describe the nystagmus characteristics of subjects with molecularly confirmed CNGB3-associated achromatopsia and report the spectral domain optical coherence tomography (SD-OCT) findings in these individuals. METHODS: Adults and children with CNGB3-achromatopsia underwent visual acuity testing, ocular motility assessments, video nystagmography, and SD-OCT imaging. Qualitative assessment of foveal structure was performed by grading SD-OCT images into one of five categories. RESULTS: A total of 18 subjects (11 adults) were included. The majority demonstrated a phoria, with manifest strabismus present in only 3 subjects. The predominant nystagmus waveform within the cohort was pure pendular. Nine individuals demonstrated a mixture of waveforms. Nystagmus frequencies were 4-8 cycles/second, with no notable differences in eye movements between adults and children. SD-OCT imaging revealed a continuous ellipsoid zone (EZ) at the fovea in 2 subjects (grade 1) and EZ disruption (grade 2) in the remaining 16. Retinal structure characteristics were symmetrical in both eyes in each subject. CONCLUSIONS: In our study cohort, nystagmus in CNGB3-associated achromatopsia had distinctive features, and the majority of subjects had retinal abnormalities at the fovea on SD-OCT. Early use of SD-OCT in the clinical work-up may eliminate the need for more invasive investigations, such as neuro-imaging.
PURPOSE: To describe the nystagmus characteristics of subjects with molecularly confirmed CNGB3-associated achromatopsia and report the spectral domain optical coherence tomography (SD-OCT) findings in these individuals. METHODS: Adults and children with CNGB3-achromatopsia underwent visual acuity testing, ocular motility assessments, video nystagmography, and SD-OCT imaging. Qualitative assessment of foveal structure was performed by grading SD-OCT images into one of five categories. RESULTS: A total of 18 subjects (11 adults) were included. The majority demonstrated a phoria, with manifest strabismus present in only 3 subjects. The predominant nystagmus waveform within the cohort was pure pendular. Nine individuals demonstrated a mixture of waveforms. Nystagmus frequencies were 4-8 cycles/second, with no notable differences in eye movements between adults and children. SD-OCT imaging revealed a continuous ellipsoid zone (EZ) at the fovea in 2 subjects (grade 1) and EZ disruption (grade 2) in the remaining 16. Retinal structure characteristics were symmetrical in both eyes in each subject. CONCLUSIONS: In our study cohort, nystagmus in CNGB3-associated achromatopsia had distinctive features, and the majority of subjects had retinal abnormalities at the fovea on SD-OCT. Early use of SD-OCT in the clinical work-up may eliminate the need for more invasive investigations, such as neuro-imaging.
Authors: Katie M Litts; Erica N Woertz; Michalis Georgiou; Emily J Patterson; Byron L Lam; Gerald A Fishman; Mark E Pennesi; Christine N Kay; William W Hauswirth; Michel Michaelides; Joseph Carroll Journal: Transl Vis Sci Technol Date: 2021-01-07 Impact factor: 3.048