Ocular dominance switches after small incision lenticule extraction and its influencing factors

Auhtors: Zou Haohan, Wang Yan, Cui Tong, Zhang Lin, Zhang Jiamei, Xu Lulu

DOI: 10.3760/cma.j.cn115989-20190306-00101

Published 2022-11-10

Cite asChin J Exp Ophthalmol, 2022, 40(11): 1085-1089.

Abstract [View PDF] [Read Full Text]

Objective

To investigate the changes, distribution and influencing factors of ocular dominance after small incision lenticule extraction (SMILE).

Methods

A retrospective observational case series study was conducted.One hundred and twelve patients (224 eyes) with an average age of 25.1±5.4 years who underwent SMILE surgery at Tianjin Eye Hospital from November 2017 to February 2018 were enrolled.There were 42 male and 70 female patients.The dominant eye was determined using the hole-in-the-card test before and after the surgery.Subjective and objective refraction and uncorrected visual acuity examination were performed before operation, and 1 day, 1 week, 1 month and 3 months after operation.The subjects were divided into switch group and non-switch group based on whether the dominant eye changed after surgery.Binary logistic regression was used to analyze the main influencing factors of dominant eye switches.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Tianjin Eye Hospital (No.201905). Written informed consent was obtained from each patient before any medical examination.

Results

There were 18 patients (16.1%) in the switch group including 7 males (38.9%) and 11 females (61.1%), and 94 patients (83.9%) in the non-switch group including 35 males (37.2%) and 59 females (62.8%). No statistically significant difference was found in sex between the two groups (χ²=0.02, P=0.89). At 1 month and 3 months after the surgery, there was a statistically significant difference in the cylindrical power between the dominant and non-dominant eye (t=2.31, 1.95; both at P<0.05). Binary logistic regression equation showed that spherical equivalent[odds ratio (OR)=0.47, 95%confidence interval (CI): 0.35-0.66]and refractive error difference (OR=3.04, 95%CI: 2.12-4.36) were significantly related to the eye dominance switches.

Conclusions

There were 16.1% of patients having eye dominance switches after SMILE.The dominant eye transfomation is associated with higher spherical equivalent and anisometropia difference before surgery.