Evaluation of the choroidal thickness and retinal nerve fiber layer and visual fields in morbid obesity: Does bariatric surgery affect retinal structure and function?

Abstract

Purpose: The study aimed to investigate the changes in choroidal thickness (CT), retinal nerve fiber layer thickness (RNFL), and visual field parameters in morbidly obese patients following bariatric surgery. Methods: The study included 40 morbidly obese patients with body mass indexes (BMI) ≥40 who had undergone bariatric surgery (Group 1) and 40 age-and sex-matched healthy subjects with normal BMI values (Group 2). RNFL and CT measurements by optical coherence tomography (OCT) and visual field test were performed preoperatively and the 1st, 6th, and 12th months postoperatively. CT measurements were obtained from the subfoveal, nasal (N), and temporal (T) regions at distances of 500 μm and 1,000 μm from the fovea. Results: No significant pathology was detected during ophthalmological examinations following bariatric surgery. The BMIs were found to be significantly lower in all of the periods after bariatric surgery (P < 0.0001). The CT measurements decreased significantly in all periods after bariatric surgery (P < 0.0001). No differences were found in terms of the mean RNFL thicknesses in all postoperative periods (P = 0.125). Visual field tests showed no significant changes during scheduled visits. (P = 0.877). No visual field defect was detected in any patient during the follow-up periods after bariatric surgery. Conclusion: These results have suggested that CT is positively correlated with BMI and decreased with a reduction in BMI progressively. Nutritional disorders resulting from malabsorption have not caused any nutritional optic neuropathy and visual field defect for at least the first postoperative year after bariatric surgery.

Keywords

• bariatric surgery
• choriocapillaris hypoperfusion
• choroidal thickness
• obesity
• optical coherence tomography
• retinal nerve fiber layer thickness
• visual field