Findings published in Frontiers in Endocrinology indicate that the choroidal vascularity index (CVI) may represent a reliable imaging biomarker for progression in diabetic retinopathy. Researchers examined changes in the choroidal vasculature and correlations with visual acuity in diabetic retinopathy.
They study included 225 eyes, with 60 eyes from 60 healthy controls, 55 eyes from 55 participants without diabetic retinopathy, 46 eyes from 46 patients with non-proliferative diabetic retinopathy (NPDR), 21 eyes from 21 patients with proliferative diabetic retinopathy (PDR), and 43 eyes from 43 patients with clinically significant macular edema (CSME).
The CVI, subfoveal choroidal thickness (SFCT), luminal area (LA), and stromal area (SA) values of patients with diabetic retinopathy were determined to be significantly lower than both healthy controls and patients without DR (P<0.05). The SFCT was significantly higher among those in the NPDR group compared with the group without diabetic retinopathy (P<0.001); the SFCT was lower in the PDR group compared to the NPDR group (P=0.014). Furthermore, there was a gradual decline in CVI with diabetic retinopathy progression, with the lowest value in the PDR group. However, the CVI in the CSME group had “a marginally closer proximity to that of the NPDR group,” researchers noted.
The multivariate regression analysis demonstrated a positive correlation between CVI and the duration of DM as well as LA (P<0.05). Both univariate and multivariate regression analyses showed a positive correlation between CVI and best corrected visual acuity (BCVA; P=0.003). Previous studies have not assessed the relationship between BCVA and CVI in patients with diabetic retinopathy, according to investigators. While earlier research indicated that choroidal thickness (CT) impacted visual impairment caused by photoreceptor degeneration, the current study showed no significant association between BCVA and CT. This may be due to the inclusion, in the current study, of patients with diabetes who were older. Future research with larger study populations is needed to examine whether visual impairment among patients with diabetes is impacted by CT.
“CVI may serve as a reliable quantitative biomarker for monitoring the progression of [diabetic retinopathy],” researchers wrote. “Clinicians should closely monitor changes in choroidal vasculature in patients with [diabetic retinopathy] and recognize that preventing a decline in CVI may be an important clinical goal for preventing the progression of [diabetic retinopathy].”