Surgical outcome of single-staged three horizontal muscles squint surgery for extra-large angle exotropia.
OBJECTIVE
To report the surgical outcomes of 24 patients undergoing single-staged three horizontal muscles squint surgery for extra-large angle exotropia.


METHODS
Prospective case series of 24 consecutive patients with primary exotropia>60 prism diopters (PD) at distant and underwent single-staged three horizontal muscles squint surgery from 2003 to 2006. Surgery consisted of bilateral lateral rectus recession of 9.0 mm for 50 PD exotropic correction. For every 5 PD remaining angle exceeding 50 PD, we additionally performed 1.0 mm of unilateral medial rectus resection. The mean follow-up period was 15.8 months (range 6.0-38.0 months; SD 9.5 months).


RESULTS
The mean age at surgery was 31.2 years old (range 7-78 years old, SD 18.2 years old). The mean distant preoperative deviation was 71.3 PD (range 60-85 PD, SD 7.7 PD). No limitation of eye movement or diplopia was found. The success rate was higher in the intermittent group (88.2%) than the constant group (42.9%) (P=0.02) and in cases with preoperative deviation of <80 PD (84.2%) compared with those with deviation>or=80 PD (40.0%) (P=0.042).


CONCLUSIONS
Measurement of preoperative deviation and the surgery for extra-large angle exotropia made management of this condition difficult. Single-staged three horizontal muscles squint surgery can be one of the options. Further researches on management of exotropia of >80 PD are warranted.
Hong Kong Eye Hospital, and Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Kowloon, Hong Kong, People's Republic of China.
F H S
FH
Lau
D S P
DS
Fan
W W K
WW
Yip
C B O
CB
Yu
D S C
DS
Lam
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005099:Exotropia / Q000503:physiopathology / Q000601:surgery*; D053483:Eye Movement Measurements; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009801:Oculomotor Muscles / Q000601:surgery*; D013508:Ophthalmologic Surgical Procedures; D011446:Prospective Studies; D055815:Young Adult