Abstract
Purpose :
To report the clinical characteristics and their response to eye muscle surgery in children with dyschromatopsia
Methods :
This is a prospective cohort analysis of 15 dyschromatopsic patients who had eye muscle surgery. Data collected included: 1) demography, 2) clinical and electrophysiological findings, 3) associated non-ophthalmic characteristics, 5) special testing findings and 7) treatments and their results.
Results :
The data were collected prospectively as an IRB approved registry. Age range 3mos-12yrs (~7.2yrs) (FU 1-10yrs), 53% male, 23% were other than Caucasian, 17% premature, 94% had delayed visual maturation, 100% had INS, 86% (13/15) with a dual jerk waveform, 100% no vergence damping, latent component or periodicity, 53% had strabismus, 40% had amblyopia, 93% had an anomalous head posture (predominant chin-down), 100% had a significant refractive error, 47% with anisometropia. Ellipsoid and/or outer retina dysmorphology was present in 100%. ERG testing showed cone dysfunction in 100% with varied rod dysfunction in 6, (40%). Positive CNGA3, CNGB3 or CAPB4 homozygosity was found in 4 patients. Systemic findings were present in 29%. Optical and amblyopia treatments were completed prior to eye muscle surgery in all patients. Best binocular acuity after eye muscle surgery ranged from Log MAR 0.55-1.2 (~.72) with a group mean improvement of .24 Log MAR (p<0.01). In addition, all patients had improvement in contrast sensitivity and their nystagmus characteristics, including; foveation and breadth, depth and position of their eccentric null zones.
Conclusions :
A less common waveforms seen in patients with INS is dual jerk (DJ) or dual pendular which are etiologically connected to disruption in the nucleus of the optic tract. DJ INS is a low-amplitude, high-frequency nystagmus whereas typical INS is a high-amplitude, low-frequency nystagmus, the combination of the two is recognized using eye-movement recordings and seems to be characteristic in dyschromatopsia. In addition to confirming some of the typical clinical characteristics of dyschromatopsia-achromatopsia this series analysis has demonstrated a unique, consistent, pattern of novel ocular motor findings and significant improvements nystagmus and visual function after eye muscle surgery.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.