Abstract
Purpose :
In patients with diabetes, retinal capillary non-perfusion often precedes ophthalmoscopically visible lesions such as microaneurysms and dot hemorrhages. Signs of capillary perfusion loss have been detected in children and adolescents with a duration of diabetes shorter than 10 years. The purpose of this ongoing study is to map capillary perfusion loss in type I diabetes from early childhood.
Methods :
This observational study has currently enrolled 50 participants with type I diabetes and 31 age-matched healthy control subjects. Patient age range was 6-32 (mean 15) years and diabetes duration 14.5-17.5 years (n = 8), 9-11.5 years (n = 14), 4.5-6 years (n = 17), and 0-4 months (n = 11). In healthy controls, the age range was 8-34 (mean 16) years. Exclusion criteria were significant chronic systemic disease other than diabetes and ocular disease other than diabetic retinopathy. Examinations included 3x3 mm macular optical coherence tomography angiography scans (OCTA; Topcon Triton) and fundus photography (Optos). Capillary densities of four different ETDRS grid sectors of the macula were calculated using proprietary software (Topcon ImageNet6) (fig. 1).
Results :
Of 50 patients with type I diabetes, seven had very mild and two had mild non-proliferative diabetic retinopathy. Superficial capillary plexus density in patients with diabetes duration 14.5-17.5 years was 44.7 % (mean of temporal sector), compared to patients with shorter diabetes duration and healthy subjects (mean temporal sector densities 47.8 % and 47.6 %, respectively). The numerical deficit in the grid sectors decreased in the order nasal, inferior, temporal, superior. Three of the eight patients with a density below 44.7 % had fundus photographic retinopathy, the rest did not.
Conclusions :
Preliminary data from this observational study of patients with type I diabetes suggest that decreased macular capillary density can be detected after a diabetes duration of 15 years and before it can be seen on color fundus photographs. Full enrolment and longer observation time may provide more definite information about these issues.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.