Evaluation of Choroidal Vascular Index in Amblyopic Patients

Abstract

Objectives: To compare subfoveal choroidal thickness (SFCT) and choroidal vascular index (CVI) in patients with hyperopic refractive and strabismic amblyopia and healthy subjects.

Materials and methods: The study included 17 patients with strabismic amblyopia (Group 1), 29 patients with hyperopic refractive amblyopia (Group 2), and 16 eyes of 16 healthy volunteers (Group 3). Best corrected visual acuity was noted in all patients and volunteers. In addition to detailed anterior and posterior segment examinations, macular images were obtained by enhanced-depth imaging mode of optical coherence tomography (OCT). SFCT measurements were made from these images and CVI was calculated using the Image J program.

Results: No significant difference was found between the groups in terms of age, gender, and intraocular pressure (p=0.27, 0.64, and 0.85, respectively). Mean BCVAs in Group 1 were 0.57±0.16 (0.3-0.8) in the amblyopic eyes, 0.94±0.08 (0.8-1.0) in the fellow eyes, and in Group 2 were 0.61±0.17 (0.2-0.8) in amblyopic eyes, 0.92±0.1 (0.8-1.0) in fellow eyes. BCVA in Group 3 was 1.0±0 (1.0-1.0). Mean SFCT of the amblyopic eyes in Groups 1 and 2 was 341.50±60.4 (277-481) and 370.06±65.3 (247-462), respectively, and in the healthy eyes of Groups 1 and 2 and Group 3 was 321.92±68.26 (251-440), 330.35±74.00 (194-502), and 327.62±40.79 (238-385), respectively. SFCT was significantly greater in the amblyopic eyes of Group 2 compared to Group 3 (p=0.01). Mean CVI was 0.681±0.032 (0.642-0.736) in the amblyopic eyes and 0.685±0.054 (0.587-0.788) in the fellow eyes of Group 1 patients; 0.664±0.033 (0.592-0.719) in the amblyopic eye and 0.707±0.039 (0.625-0.779) in the fellow eye in Group 2 patients; and 0.689±0.031 (0.612-0.748) in Group 3 patients. CVI was significantly lower in the amblyopic eyes of Group 2 compared with fellow eyes (p=0.02) and Group 3 (p=0.025).

Conclusion: Morphological changes may be seen in the choroid in amblyopic eyes. We observed that the choroidal stromal component is increased in hyperopic amblyopic patients especially.

Keywords: Amblyopia; choroidal thickness; choroidal vascularity index.