Clinical features and surgical treatment of A-pattern exotropia.
OBJECTIVE
To investigate the clinical characteristics and determine the effective surgical managements of A-pattern exotropia.


METHODS
Thirty-two patients with A-pattern exotropia underwent superior oblique muscle weakening procedures, medial rectus resection or (and) lateral rectus recession. Pre- and post-operative eye position, deviation angle, superior oblique function and binocular vision were examined and analyzed in the cases.


RESULTS
Overaction of the superior oblique muscles (31/32) and underaction of the medial rectus muscle (20/32) were presented in the cases. Postoperatively, a satisfactory ocular alignment was obtained in 28 cases (87.5%), and the A-pattern was corrected in 31 cases (96.9%). Four cases got binocular vision after surgery.


CONCLUSIONS
As one of the most common forms of A and V patterns, A-pattern exotropia showed clinical characteristics of superior oblique muscle overaction and medial rectus muscle underacion, which should be the primary factors in the etiology of A-pattern exotropia, and superior oblique weakening procedures combined with horizontal surgery should be an effective approach to A-pattern exotropia treatment.
Chen
Jingchang
J
Zhongshan Ophthalmic Center, Sun Yan-san University, Guangzhou 510060, China.
Mai
Guanghuan
G
Deng
Daming
D
Lin
Xiaoming
X
Guo
Yan
Y
Yang
Xiao
X
Yuan
Chunxiu
C
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003867:Depth Perception / Q000502:physiology; D005099:Exotropia / Q000145:classification / Q000503:physiopathology / Q000601:surgery*; D005133:Eye Movements / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009801:Oculomotor Muscles / Q000503:physiopathology / Q000601:surgery*; D013508:Ophthalmologic Surgical Procedures / Q000379:methods; D012189:Retrospective Studies; D015348:Vision, Binocular