Abnormal retinal autoregulation is detected by provoked stimulation with flicker light in well-controlled patients with type 1 diabetes without retinopathy.
OBJECTIVE
Investigation of retinal vasodilation under flickering light is considered a dynamic analysis in contrast to the static analysis of retinal vessel equivalents (mean retinal vessel diameter). We investigated whether dynamic analysis apart from the static one in type 1 diabetic patients without diabetic retinopathy with well-controlled diabetes could lead to additional information regarding retinal autoregulation.


METHODS
18 normotensive type 1 diabetic patients without retinopathy and 19 healthy subjects were included. Diameter of retinal vessels was measured with Dynamic Vessel Analyzer. Changes in vasodilation are expressed as percent change over baseline values.


RESULTS
HbA(1c) was 7.5+/-1.0% in diabetic patients. In arteries, the response to flicker was diminished in diabetic patients compared to healthy volunteers (p<0.023). In patients flicker stimulation increased arterial diameter by +2.7% in contrast to +4.4% in controls. Venous vessel diameter increased by +3.1% in diabetic individuals and by +5.3% in the control group (p<0.002). There were no differences in static analysis between both groups.


CONCLUSIONS
Diabetic patients without retinopathy with relatively good glycemic control show reduced retinal vasodilation after flicker indicating dysfunction in retinal autoregulation. The use of provocation test in conjunction with static analysis could lead to additional information regarding abnormal retinal autoregulation.
Mandecka
Aleksandra
A
Department of Internal Medicine III, Friedrich- Schiller University, Jena, Germany. Aleksandra.Mandecka@med.uni-jena.de
Dawczynski
Jens
J
Vilser
Walthard
W
Blum
Marcus
M
Müller
Nicolle
N
Kloos
Christoph
C
Wolf
Gunter
G
Müller
Ulrich Alfons
UA
D000328:Adult; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D012171:Retinal Vessels / Q000473:pathology* / Q000503:physiopathology; D014664:Vasodilation / Q000502:physiology; D055815:Young Adult