Categories
Nevin Manimala Statistics

Achromatopsia and infantile nystagmus syndrome (INS): Outcome after eye muscle surgery

Indian J Ophthalmol. 2026 Apr 1;74(4):499-507. doi: 10.4103/IJO.IJO_1977_25. Epub 2026 Mar 26.

ABSTRACT

PURPOSE: The purpose of this report is to characterize the effects of eye muscle surgery on children with achromatopsia and infantile nystagmus syndrome (INS) who have had no previous surgery.

DESIGN: This is a prospective, single-center, interventional case series analysis of 17 patients’ clinical and electrophyisological data before and after eye muscle surgery.

METHODS: Outcome measures included: demographic and clinical characteristics, binocular best-corrected visual acuity (BCVA), strabismic deviation (SD), anomalous head posture (AHP), contrast sensitivity function (CSF), and the expanded nystagmus acuity function (NAFX). Postoperative data were collected between 6 and 9 months after surgery and statistical analysis perfomed.

RESULTS: The age at surgery ranged from 19 months to 12 years (~7.2 years), 53% were male, and 23% were other than Caucasians. Follow-up ranged 9 months -10 years (~ 4.3 years). Nine patients had strabismus. All had a significant refractive error, and 7 patients had amblyopia. Sixteen had abnormal SD-OCT dysmorphology. All had the unique INS waveform of dual-jerk. In 13 patients, a molecular diagnosis was obtained. A surgical algorithm involving at least 2 recti muscles on each eye was perfomed on every patient. There were no surgical complications with a reoperation rate of 12%. Along with unique unexpected improvements in blepharospasm and photophobia, there were improvements in AHP, SD, BCVA, CSF, and the NAFX.

CONCLUSIONS: Achromatopsia has unique associations of a vertical AHP and dual-jerk INS waveforms. In spite of their associated retinal disease, patients with achromatopsia show improvements in many afferent and efferent measures of ocular motor and visual functions after eye muscle surgery for nystagmus.

PMID:41884912 | DOI:10.4103/IJO.IJO_1977_25

By Nevin Manimala

Portfolio Website for Nevin Manimala