Retro-equatorial inferior oblique myopexy for treatment of inferior oblique overaction.
AIM
To compare the effectiveness of inferior oblique retroequatorial myopexy and inferior oblique myectomy in correction of inferior oblique overaction (IOOA).


PATIENTS AND METHODS
This was a pilot study study including forty patients with primary IOOA of all grades, with or without primary position horizontal deviations. Patients were randomized to have either IO retroequatorial myopexy, group A, or IO myectomy, group B. Success was defined as elimination of the IOOA at 6 months postoperatively. Secondary outcome measures included residual or recurrent elevation in adduction, development of postoperative hypotropia in adduction, postoperative contralateral IOOA, major intraoperative complications, and reversibility of the procedure.


RESULTS
At 6 months postoperative, the success rate was higher in the myectomy group (76%) than in the myopexy group (58%); however, this difference was not statistically significant (P = 0.1). The incidence of residual IOOA in myopexy group was significantly higher in patients with higher preoperative grades of IOOA (P ˂ 0.001). While this difference was not statistically significant among patients in myectomy group (P = 0.09). Collapse of V-pattern was acheived in nine (69%) patients in myopexy group compared with 8 (57%) in myectomy group with a statistically significant difference (P ≤ 0.001). No patients in myopexy group developed postoperative hypotropia in adduction or postoperative contralateral IOOA, compared with eight (22%) patients of myectomy group (P = 0.002) who developed postoperative hypotropia and two (66.6%) patients with unilateral IOOA who developed contralateral IOOA in myectomy group (P ˂ 0.001). No intraoperative complications were encountered in either group. postoperative.


CONCLUSIONS
Retroequatorial myopexy of the inferior oblique is as effective as inferior oblique myectomy in eliminating lower and moderate grades of primary IOOA; however, it is more effective in collapsing V-pattern associated with IOOA, and is not associated with postoperative hypotropia or contralateral IOOA after unilateral surgery. It can be used as a safe, reversible alternative to myectomy; however, it is not suitable for high grades of IOOA.
['Kasem|Manal|M|', 'Metwally|Heba|H|', 'El-Adawy|Ibrahim T|IT|', 'Abdelhameed|Ameera G|AG|https://orcid.org/0000-0002-9508-8708']
D000293:Adolescent D000328:Adult D002648:Child D002675:Child, Preschool D005133:Eye Movements D005260:Female D006801:Humans D008297:Male D009801:Oculomotor Muscles D013508:Ophthalmologic Surgical Procedures D010865:Pilot Projects D011184:Postoperative Period D013285:Strabismus D016896:Treatment Outcome D015348:Vision, Binocular D055815:Young Adult
Inferior oblique myopexy Inferior oblique overaction Retroequatorial myopexy Inferior oblique myectomy V-pattern Faden