Consecutive Esotropia in Intermittent Esotropia Patients with Immediate Postoperative Overcorrection More Than 17 Prism Diopters
Published on Sep 1, 2007in Korean Journal of Ophthalmology
· DOI :10.3341/KJO.2007.21.3.155
While intermittent exotropia (X(T)) recurs in 20~30% of patients after surgery,1-11 consecutive esotropia (ET) arises in 2~20% because of overcorrection.12-16 Once consecutive ET has occured, the patient can suffer from cosmetic problems and diplopia. Moreover, suppression, amblyopia, and deterioration of stereovision may occur later.17 Lateral incomitancy, medial rectus muscle contracture, and overcorrection of at least 20 prism diopters (PD) immediately after surgery have been reported as risk factors for consecutive ET.9,11,15,18,19 Many studies reported that overcorrection of 11~20 PD immediately after surgery was optimal for the prevention of consecutive ET.6,9,11,16 Raab and Parks4 suggested that in cases of overcorrection that exceeds 17 PD, the occurrence of consecutive ET increased. Kim and Hwang20 reported that 6% of patients who have had overcorrection over 20 PD developed consecutive ET. The purpose of this study was to investigate the incidence and factors in the development of consecutive ET in patients with immediate postoperative overcorrection of at least 17 PD after surgery for X(T).