Abstract
Purpose :
The purpose of this report is to characterize the effects of standard eye muscle surgery on the visual function and nystagmus of patients greater than or equal to 18 years of age with INS.
Methods :
This is an IRB approved, prospective, interventional case series analysis of clinical and electrophyisological data after eye muscle surgery in 81 adults with INS. Outcomes included: 1) routine demography and surgical procedure 2) binocular corrected visual acuity in the null position (BVA) in LogMAR, 3) anomalous head posture (AHP) in degrees, 4) binocular contrast sensitivity function (CS) in cycles/degree, 5) strabismic deviation (SD) using alternate cover test in prism diopters and 6) eye movement data to calculate the nystagmus acuity function (NAFX). All patients were followed at least 12 months. Parametric and non-parametric statistical analysis of all outcome measures were perfomed.
Results :
81 patients were studied, ranging from 18-72 yrs (ave 36.6 yrs). 63% were male. Follow up ranged from 13-78 mos (ave 33 mos). Associated systemic and ocular system deficits included albinism (25%), amblyopia (24%), optic nerve dysplasia and/or retinal dystrophy (24%). 61% had a significant refractive error, 44% had an eye movement recording confirmed eccentric null position with a clinically significant AHP, 44%% had a periodic or aperiodic component, 70% had a tropic strabismus. There were 9 consistent surgical procedures used with the most common being that for a horizontal head posture plus strabismus (22%) (Figure withTable). There were no serious surgical complications. Group means improved in BVA (p<0.05), CS (P<0.01), SD (p<0.05), AHP (p<0.001), and NAFX measures (p < 0.01). There were 12 (15%) reoperations within 5 years of the first procedure, most commonly for recurrent strabismus and/or new head posturing
Conclusions :
Using standard eye muscle surgical techniques, adult patients who have INS with or without associated sensory system deficits, show sustained improvement in many afferent and efferent measures of visual function.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.