Decrease in Choroidal Vascularity Index of Haller’s layer in diabetic eyes precedes retinopathy

Abstract

IntroductionThe study aimed to evaluate Choroidal Vascularity Index (CVI) of Haller’s and Sattler’s layers and their relationships with choroidal and retinal thickness, volumes measured on enhanced depth imaging–optical coherence tomography (OCT) scans in the eyes of patients without diabetes, patients with diabetes with no diabetic retinopathy (DR) and patients with diabetes and DR.Research design and methodsRetrospective analysis of 165 eyes from 84 Singapore Indian Eye Study-2 study participants (group 1: no diabetes, group 2: diabetes with no DR and group 3: with DR). Groups 1 and 2 were matched by age and gender from group 3.ResultsIn the eyes of patients with diabetes without DR, the macular CVI of Haller’s but not Sattler’s layer was significantly reduced compared with eyes of patients without diabetes. Eyes with >5 years of diabetes have significantly decreased CVI of Sattler’s layers (mean difference=0.06 ± 0.10, p=0.04) and also decreased subfoveal choroidal volume (mean difference=0.89 ± 0.16 mm3, p=0.02), compared with those with ≤5 years of diabetes.ConclusionDiabetic eyes without DR had significantly lower CVI of macular Haller’s layer than those of healthy controls. With a longer duration of diabetes, CVI of subfoveal Sattler’s layer and choroidal volume continue to decrease, irrespective of diabetic control, suggesting that early diabetic choroidopathy mainly affects larger choroidal veins initially before medium-sized arterioles. The CVI of macular Haller’s layer could potentially be used as a marker on spectral domain OCT imaging in newly diagnosed patients with diabetes for the onset of DR and as a possible prognostication tool in diabetic eyes. Future prospective longitudinal studies in diabetic eyes would be useful in establishing the relationship between CVIs of Haller’s and Sattler’s layer with visual acuity as a marker of photoreceptor health and visual prognosis.

Analysis of the Choroid and Its Relationship with the Outer Retina in Patients with Diabetes Mellitus Using Binarization Techniques Based on Spectral-Domain Optical Coherence Tomography

“…When we further compared control mean values with our pooled DM group, LA, SA and TCA were significantly decreased in patients with DM, consistently with other studies [ 14 , 38 , 39 ]. Previous studies on the association between choroidal thickness and DR stage found a decreased thickness in patients with DM [ 12 , 14 ]. Interestingly, when we compared FChT between the NDR and DR groups, we found increased mean values in the DR group, 295.43 ± 86.83 µm vs. 269.51 ± 94.22 µm in NDR, although not statistically significant ( p = 0.332), as found by Xu et al and Tan et al [ 14 , 40 ].…”

“…Ferrera et al have demonstrated a loss of intermediate and large vessels in Sattler’s and Haller’s layer in patients with DM [ 11 ]. Analysis of the choroidal vasculature anatomy showed that it is divided into small vessels that form the superficial choriocapillaris, medium-sized vessels consisting mainly of choroidal arterioles that form Sattler’s layer and deeper large vessels composed mostly of choroidal veins that form Haller’s layer [ 12 ]. It was observed that in eyes with diabetes but no DR, the choroidal vascularity index (CVI) decreases preferentially in larger choroidal veins (Haller’s layer) before medium-sized arterioles (Sattler’s layer) or smaller choriocapillaris, while the eyes with more than 5 years duration of diabetes had a lower macular CVI of Sattler’s layer when compared to the control group [ 12 ].…”

Choroidal changes and associations with visual acuity in diabetic patients

“…The small size of these groups, the different age, the higher variability of measurements or a true absence of difference may justify not reaching significance. Some previous studies have found a reduced CVI in DM patients without DR [ 25 – 27 ], while other have not [ 18 – 21 ]. It remains unclear if diabetic choroidopathy can be detected before classic retinopathy.…”

Choroidal vascularity index of patients with coronary artery disease

“…First, our sample size was small and not evenly distributed among three different CAD severity groups. Although we performed multivariate analysis to reduce the confounding effects of the variables, there were significant differences in terms of underlying diseases such as diabetes and hypertension, among different groups which are known to be associated with a choroidal thickness or CVI values 20 – 22 . Second, although those in the no CAD group did not have significant coronary stenosis, there was no healthy control group without cardiovascular risk factors or symptoms.…”