Comparison of different surgery procedures for convergence insufficiency-type intermittent exotropia in children.
OBJECTIVE
To compare prospectively the surgical outcomes of different surgery procedures for convergence insufficiency (CI)-type intermittent exotropia (IXT) in children.


METHODS
Forty-five children with CI-type IXT were included in this prospective surgical study with 6 months follow-up. According to the different surgical procedures, all children were randomly divided into three groups: the unilateral medial rectus resection (UMR) group (15 cases), the bilateral medial rectus resections (BMR) group (14 cases) and the improved unilateral recession-resection (R&R) group (16 cases). In the UMR and BMR groups, the medial rectus resection(s) were based on the distance exodeviation. In the R&R group, UMR was based on the near exodeviation while lateral rectus recession was based on the distance exodeviation. A successful surgical alignment was defined as the distant deviation in the primary gaze to be between ≤ 10 prism dioptres (PD) of exophoria/tropia and ≤ 5 PD of esophoria/tropia. The success rate, the preoperative and postoperative deviations at distance and near and near-distance differences among groups were compared.


RESULTS
At the last follow-up of 6 months, the success rate in the R&R (87.5%) group was significantly higher than those in the UMR (13.3%) and BMR (42.9%) groups (p=0.000 and 0.008); the mean exodeviations at distance and near in the R&R group were significantly different from those in the UMR and BMR groups (p=0.000 and 0.001); there were no significant differences in the mean near-distance differences between the R&R group and the other two groups (p>0.05).


CONCLUSIONS
The improved R&R procedure in which medial rectus resection based on the near deviation with lateral rectus recession based on the distant deviation has a better alignment than the UMR and BMR surgeries for the treatment of children with CI-type IXT. All the UMR, BMR and improved R&R surgery can reduce near-distance differences in children with CI-type IXT.
Department of Ophthalmology, Shandong Provincial Hospital affiliated to Shandong University, Jinan, Shandong, People's Republic of China.
Bing
B
Wang
Department of Ophthalmology, Shandong Provincial Hospital affiliated to Shandong University, Jinan, Shandong, People's Republic of China.
Lihua
L
Wang
Department of Ophthalmology, Shandong Provincial Hospital affiliated to Shandong University, Jinan, Shandong, People's Republic of China.
Qi
Q
Wang
Department of Ophthalmology, Shandong Provincial Hospital affiliated to Shandong University, Jinan, Shandong, People's Republic of China.
Meiyu
M
Ren
D002648:Child; D002675:Child, Preschool; D003290:Convergence, Ocular / Q000502:physiology; D005099:Exotropia / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D015835:Ocular Motility Disorders / Q000503:physiopathology / Q000601:surgery*; D009801:Oculomotor Muscles / Q000601:surgery*; D013508:Ophthalmologic Surgical Procedures; D011446:Prospective Studies; D015348:Vision, Binocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology
Child health (paediatrics); Muscles; Treatment Surgery