The aim of this study is to determine central macular thickness (CMT) and subfoveal choroid thickness (SFCT) in eyes with inferior oblique muscle overaction (IOOA) using spectral domain optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI) mode, as well as macular layers using OCT segmentation software.
In this retrospective study, OCT parameters collected from 42 eyes with unilateral IOOA were compared to those from 39 contralateral healthy eyes. The CMT and SFCT were measured using EDI SD-OCT, and each retinal layer was measured using SD-OCT in the central 1, 3, 6 mm areas identified by the Early Treatment Diabetic Retinopathy Study (ETDRS). Heidelberg segmentation was used to define the different layers of the macula. There were no morphological abnormalities in the macula in either eyes with unilateral IOOA or contralateral healthy eyes. The CMT, SFCT, and retinal layer thickness did not differ statistically between IOOA eyes and contralateral healthy eyes (P>0.05). Subgroups of IOOA eyes based on concomitant strabismus, which included IOOA only, IOOA plus esotropia, and IOOA plus exotropia, or by degree of IOOA, which included mild and severe forms, also revealed negligible differences in CMT, SFCT, and other retinal layer thickness (P=0.34, P=0.91, P>0.05, respectively) The total thickness of the ganglion cell and inner plexiform layer decreased non-significantly in severe IOOA compared to mild IOOA (P=0.059). Furthermore, the outer plexiform layer was non-significantly thicker in IOOA plus esotropia eyes (p=0.052). Despite the fact that IOOA had no discernible impact on CMT, SFCT, or macular layers, it is critical that this finding be confirmed by further large-scale studies comparing patients to healthy individuals.
Key words: Central macular thickness; inferior oblique overaction; macular segmentation; optical coherence tomography; subfoveal choroidal thickness
|
