The Relationship Between Stage of Diabetic Retinopathy and Retinal Blood Flow in Patients With IDDM During Euglycemic Clamp
Status:
Completed
Trial end date:
2003-12-01
Target enrollment:
Participant gender:
Summary
Impaired retinal blood flow has been implicated in the pathogenesis of diabetic retinopathy.
Patel et al. (1992) showed that retinal blood flow increases with the level of diabetic
retinopathy. Grunwald et al. (1996) reported that patients with insulin dependent diabetes
mellitus (IDDM) of relatively short duration have increased retinal blood flow, even before
the onset of diabetic retinopathy. On the other hand the data of Bursell et al. (1996)
indicate that IDDM patients have reduced retinal blood flow, when they have normal blood
glucose levels, but this study may have considerable methodological limitations. Acute
elevations of blood glucose levels, however, result in an increase in retinal blood flow
(Grunwald et al. 1987, Bursell et al. 1996). Based on previous experimental data the
investigators hypothesize that ocular blood flow is increased in early diabetes and reduced
at later stages of the disease. Previous studies have demonstrated that metabolic conditions
such as hyperglycemia influence outcome parameters and thereby might have confounded results
regarding ocular blood flow in diabetic retinopathy. The investigators will therefore study
patients with IDDM during euglycemic conditions.