Feng Lixia, Zhou Jiawei, Chen Li, Hess Robert F
Department of Ophthalmology, First Affiliated Hospital, Anhui Medical University, Hefei, Anhui, PR China.
McGill Vision Research, Dept. Ophthalmology, McGill University, Montreal, PQ, Canada.
Sci Rep. 2015 Aug 19;5:13075. doi: 10.1038/srep13075.
Surgery to align a deviated or strabismic eye is often done for both functional as well as cosmetic reasons. Although amblyopia is often an impediment to regaining full binocularity in strabismics in general, intermittent exotropes, because their deviation is intermittent, have no amblyopia and some degree of stereopsis. Binocular function, including a balanced ocular dominance, could be expected to be normal after surgical correction if normal levels of stereopsis and visual acuity are postsurgically achieved. Here we used a binocular phase combination paradigm to quantitatively assess the ocular dominance in a group of surgically corrected intermittent exotropes who have normal stereo and visual acuity as defined clinically. Interestingly, we found significant interocular imbalance (balance point < 0.9) in most of the surgically treated patients (8 out 10) but in none of the controls. We conclude that the two eyes may still have a residual sensory imbalance in surgically corrected strabismus even if stereopsis is within normal limits. Our study opens the possibility that a further treatment aimed at re-balancing the ocular dominance might be necessary in surgically treated intermittent exotropia to provide more efficient binocular processing in the long term.
为了功能和美观的原因,常常会对斜视或斜位眼进行手术使其归位。虽然一般来说,弱视常常妨碍斜视患者恢复完全的双眼视功能,但间歇性外斜视患者因其斜视是间歇性的,所以没有弱视,且有一定程度的立体视。如果术后能达到正常水平的立体视和视力,那么手术矫正后双眼功能,包括平衡的眼优势,有望恢复正常。在此,我们采用双眼相位组合范式,对一组经手术矫正的间歇性外斜视患者的眼优势进行了定量评估,这些患者临床上具有正常的立体视和视力。有趣的是,我们发现大多数接受手术治疗的患者(10例中有8例)存在明显的两眼不平衡(平衡点<0.9),而对照组无一例出现这种情况。我们得出结论,即使立体视在正常范围内,但手术矫正后的斜视患者两眼仍可能存在残余的感觉不平衡。我们的研究表明,对于手术治疗的间歇性外斜视患者,为了长期提供更有效的双眼视处理,可能有必要进一步进行旨在重新平衡眼优势的治疗。