Purchase this article with an account.
Gabor Mark Somfai, Thalmon R. Campagnoli, Jing Tian, william smiddy, Delia DeBuc; The assessment of blood flow velocities in retinal collateral and shunt vessels in diabetic retinopathy. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):1467.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Diabetes mellitus is a microvascular disease, being the major cause of legal blindness in the working aged population of developed countries. The main hallmark of diabetic retinopathy (DR) is retinal ischemia due to capillary dropout, therefore, our main goal was to assess blood flow velocities in retinal collateral and shunt vessels using a non-invasive functional imaging methodology.
We enrolled five eyes of healthy subjects (H), five eyes of four subjects with diabetes and no retinopathy (DM), three eyes of three subjects with mild non-proliferative diabetic retinopathy (MDR) and five eyes of four subjects with proliferative diabetic retinopathy (PDR). Routine ophthalmic examination was performed in all subjects followed by imaging using the Retinal Function Imager (RFI, Optical Imaging Inc., Rehovot, Israel). The built-in software of the RFI device was used to identify and segment retinal collaterals and shunts. We rejected vessel segments with >45% of velocity coefficient of variation. The number of accepted vessel segments was recorded and their absolute velocity values were exported. Comparisons were based on all qualifying vessel segments in the groups. One-way ANOVA was performed and followed by Newman-Keuls post hoc test. The level of significance was set at 5%.
The total number of qualifying collateral/shunt segments was 30, 31, 21 and 39 in the H, DM, MDR and PDR groups, respectively. The blood flow velocities in the collateral and shunt vessels were slightly lower in MDR and significantly lower in PDR (H: 1.86±0.67, DM: 1.91±0.71, MDR: 1.71±0.53, PDR: 1.37±0.58mm/s). The PDR group showed statistically significant difference in the comparisons to the H, DM and MDR groups (p=0.012, p=0.008 and p=0.043, respectively), while no other comparisons between the groups showed significance.
Our results show a decreased blood flow velocity in the collateral vessels and shunts of the retina in PDR that may be associated with capillary dropout and retinal ischemia. Further studies are warranted for the non-invasive functional assessment of retinal microvascular changes in DR to gain a better understanding of the underlying pathophysiology.
This PDF is available to Subscribers Only