Characterization of Choriocapillaris and Choroidal Abnormalities in Alport Syndrome

To analyze the characteristics of the choriocapillaris and the choroid in patients with Alport syndrome (AS) and investigate their clinical and demographic associations.

Multicenter, cross-sectional study. Forty-two eyes with AS were consecutively enrolled. A cohort of 33 healthy eyes was included as controls. Demographics and medical history were collected for each participant. Each eye underwent 3 × 3 swept-source optical coherence tomography angiography (PLEX Elite 9000 2.0; Carl Zeiss Meditec, Dublin, CA, USA) and spectral-domain OCT (Spectralis HRA2; Heidelberg Engineering, Heidelberg, Germany). Choriocapillaris flow deficit (FD) number, mean FD size, total FD area, FD density, subfoveal choroidal thickness (CT), total CT, and choroidal vascularity index (CVI) were compared between AS and control eyes. Factors associated with the FD density and the CVI in AS were explored with multivariable linear mixed models.

There was high intragroup variability in choriocapillaris and choroidal measurements in patients with AS. Choriocapillaris FD in patients with AS were more numerous compared to controls (P = 0.02). FD density in eyes with AS increased with older age (estimate = 0.31% for each year; 95% confidence interval [CI], 0.06-0.57; P = 0.02) and was higher in patients with a history of kidney transplant (estimate = 9.66% in case of positive history; 95% CI, 3.52-15.8; P = 0.006). The CVI was lower in eyes with dot maculopathy (estimate = -3.30% if present; 95% CI, -6.38 to -0.21; P = 0.04) and anterior lenticonus (estimate = -6.50% if present; 95% CI, -10.99 to -2.00; P = 0.006).

Patients with AS with kidney involvement requiring transplant may present with more severe choriocapillaris impairment. Lower choroidal vascularity was found in the presence of other ocular structural abnormalities.

An increased load of choriocapillaris flow deficits on optical coherence tomography angiography was found in patients with Alport syndrome who also had severe kidney disease requiring transplant.