Purpose:
To validate a table of amounts of three horizontal muscle surgery in patients with large angle infantile esotropia (≥ 60 PD).
Methods:
Postoperative alignment was recorded in 69 patients (35 male, 34 female) over a 15 year period. Surgery amounts were according to a published table developed on a prior patient cohort (n=49)(Forrest MP et al, 2003) using bilateral medial rectus recession with graded unilateral lateral rectus resection. K-M life table survival curves were formulated for success after one and subsequent horizontal muscle surgeries for up to 10 years follow up.
Results:
The mean preoperative deviation was 67.54 PD (range 65-80) and median age at surgery was 12 months (range 5.1 months -3.6 yrs) with median follow up 3.1 years (range 0.01 - 14.5 yrs). There was no difference in preoperative characteristics of the two surgical cohorts. Surgical success to orthotropia (+/-10PD) after one surgery was 96.8% at 2, 93.5% at 6, 90.2% at 12 months, 76.8% at 6 and 71.9% at 10 yrs. Postoperative failure requiring further horizontal surgery occurred in 18.8% (undercorrection 3, overcorrection 10). Median time to failure was 23.7 months (undercorrection 12.8 months, overcorrection 27.1 months). Only two patients required more than two horizontal surgeries. Data analysis was ceased after 10 years due to the author’s (GG) practice to discharge at 8-9 years of age if the uncorrected alignment was orthotropic.
Conclusions:
Our second cohort has reproduced the success rate of the prior cohort (70.6% at 6 yrs). If the published table of surgical amounts is used, three horizontal muscle squint repair in large angle infantile esotropia appears to have a good long term success rate, and does not lead to the high rates of either undercorrection or consecutive exotropia reported by others in the literature.
Keywords: strabismus • strabismus: treatment