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Published in: Trials 1/2023

Open Access 01-12-2023 | Strabismus | Study protocol

Surgical treatment versus observation in moderate intermittent exotropia (SOMIX): study protocol for a randomized controlled trial

Authors: Tao Shen, Jingchang Chen, Ying Kang, Daming Deng, Xiaoming Lin, Heping Wu, Jinrong Li, Zhonghao Wang, Xuan Qiu, Ling Jin, Jianhua Yan

Published in: Trials | Issue 1/2023

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Abstract

Background

Intermittent exotropia (IXT) is the most common type of strabismus in China, but the best treatment and optimal timing of intervention for IXT remain controversial, particularly for children with moderate IXT who manifest obvious exodeviation frequently but with only partial impairment of binocular single vision. The lack of randomized controlled trial (RCT) evidence means that the true effectiveness of the surgical treatment in curing moderate IXT is still unknown. The SOMIX (surgical treatment versus observation in moderate intermittent exotropia) study has been designed to determine the long-term effectiveness of surgery for the treatment and the natural history of IXT among patients aged 5 to 18 years old.

Methods/design

A total of 280 patients between 5 and 18 years of age with moderate IXT will be enrolled at Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. After initial clinical assessment, all participants will be randomized to receive surgical treatment or observation, and then be followed up for 5 years. The primary objective is to compare the cure rate of IXT between the surgical treatment and observation group. The secondary objectives are to identify the predictive factors affecting long-term outcomes in each group and to observe the natural course of IXT.

Discussion

The SOMIX trial will provide important guidance regarding the moderate IXT and its managements and modify the treatment strategies of IXT.

Trial registration

ClinicalTrials.gov: NCT 02736526. Registered April 13, 2016 
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Metadata
Title
Surgical treatment versus observation in moderate intermittent exotropia (SOMIX): study protocol for a randomized controlled trial
Authors
Tao Shen
Jingchang Chen
Ying Kang
Daming Deng
Xiaoming Lin
Heping Wu
Jinrong Li
Zhonghao Wang
Xuan Qiu
Ling Jin
Jianhua Yan
Publication date
01-12-2023
Publisher
BioMed Central
Published in
Trials / Issue 1/2023
Electronic ISSN: 1745-6215
DOI
https://doi.org/10.1186/s13063-023-07189-0

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