Macular and Peripapillary Choroidal Thickness in Patients With Keratoconus.

Background and

Objective: To investigate and compare macular and peripapillary choroidal thickness and profiles of patients with keratoconus and age-matched controls and correlate subfoveal choroidal thickness with keratoconus severity. Patients and

Methods: This was a prospective, observational, cross-sectional study comprising 45 keratoconus patients and 56 healthy controls. Choroidal thicknesses at the fovea and at 750-μm intervals from the fovea to 1.5 mm in the nasal and temporal directions were measured by spectral-domain optical coherence tomography. Peripapillary choroidal thickness was measured at six segments along the circle scan.

Results: Mean age did not differ between the patients with keratoconus and controls (24.5 ± 7.2 vs. 22.5 ± 7.4 years, P = .170). Mean subfoveal choroidal thickness was higher in the keratoconus group (427.48 μm ± 78.51 μm) than in controls (351.03 μm ± 99.08 μm; P < .001). Mean subfoveal choroidal thickness did not differ between mild and severe keratoconus (437.82 ± 53.4 vs. 418.87 ± 113.9 μm; P = .660). In the macular area, choroidal thickness was lower at 1.5 mm nasal to the fovea (P < .0001) in both groups. The choroid was thinner at 0.75 mm temporal to the fovea than under the fovea in the keratoconus group (P < .001). The peripapillary choroid was thinner in the inferonasal and inferotemporal segments than in the other segments in both groups (P < .001). The peripapillary choroid was thinner in the inferonasal segment than in the inferotemporal segment in the keratoconus group (P = .018).

Conclusion: Subfoveal choroidal thickening is observed in keratoconus eyes. The pathophysiological role of choroidal thickness variations should be considered in the natural history of keratoconus. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:664-673.].