Affiliations: Department of Medical Pathology, University of California, Davis Medical Center, Sacramento, CA, USA | Department of Ophthalmology, University of California, Davis Medical Center, Sacramento, CA, USA | Shiley Center, Scripps Clinic, La Jolla, CA, USA
Note: [] Corresponding author: Wilson J. To, Department of Medical Pathology, Research-III Building, Suite 3400, University of California, Davis Medical Center, 4645 Second Avenue, Sacramento, CA 95817, USA. Tel.: +1 916 734 0571; Fax: +1 916 734 2698; E-mail: wilson.to@ucdmc.ucdavis.edu
Abstract: We hypothesized that T2DM vasculopathy can be revealed and quantified in the bulbar conjunctiva prior to its pathologic presentation in the retina. Using computer-assisted intravital microscopy (CAIM), an objective, non-invasive approach can provide a viable complement to retinal fundus photography to possibly screen patients for early signs of real-time, in vivo T2DM vasculopathy. Fundus photography was utilized to determine the retinopathy level (RL) in T2DM patients with non-proliferative diabetic retinopathy (NPDR) and control subjects. CAIM was used to quantify microangiopathy in the bulbar conjunctiva in the same patients, and reported on a severity index (SI). The average RL for the T2DM patients in this study is 19.68 ± 9.91, which differs from control subjects (RL = 10 ± 0.0; p < 0.05). A significant difference in vasculopathy was observed in the conjunctival microcirculation in the same patients (SI = 5.81 ± 1.30) when compared with control subjects (SI = 1.33 ± 1.58; p < 0.05). The results provide evidence that significant vasculopathy had developed in the microcirculation in the bulbar conjunctiva, though diabetic retinopathy had not developed significantly in the same patients – indicative of the presence of a time window for early intervention of T2DM before non-proliferative retinopathy develops, and the real-time availability of the conjunctival microvasculature as an in vivo platform to monitor disease progression.
