[Vasoconstriction of retinal arterioles with oxygen breathing in diabetic retinopathy].
OBJECTIVE
The retinal vessel analyzer (RVA) offers the unique opportunity of noninvasive online measurements of retinal vessel diameters. Breathing 100% oxygen is used to test vessel contractility of retinal arterioles in different stages of diabetic retinopathy (DR).


METHODS
After a 3-min baseline measurement 40 patients with diabetes were exposed to 100% oxygen breathing for a 5-min period. The diameter of a retinal arteriole was measured with the RVA continuously during this time. Subjects were divided into four groups according to different stages of DR. Group I: no RD; group II: mild/moderate RD; group III: moderate/severe nonproliferative RD with laser treatment; group IV: proliferative RD with laser treatment.


RESULTS
Group I (n=12) demonstrated a vasoconstriction of 6.2% (+/-4.0). In group II (n=8) 6.1% (+/-2.8) and in group III (n=8) 6.6% (+/-4.1) vasoconstriction was found. Group IV (n=12) presented a vasodilatation of +2.5% (+/-4,7).


CONCLUSIONS
No significant differences could be found in the vasoreaction to 100% oxygen breathing in different stages of nonproliferative RD. However, a significant reduction could be demonstrated in proliferative DR with this method.
Blum
M
M
Augenklinik Helios Klinikum Erfurt. mblum@erfurt.helios-kliniken.de
Vollrath
D
D
Bartke
T
T
Bachmann
K
K
Strobel
J
J
D000280:Administration, Inhalation; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001160:Arterioles / Q000503:physiopathology; D003627:Data Interpretation, Statistical; D003930:Diabetic Retinopathy / Q000097:blood / Q000503:physiopathology* / Q000601:surgery; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007091:Image Processing, Computer-Assisted; D053685:Laser Therapy; D008875:Middle Aged; D010100:Oxygen / Q000008:administration & dosage* / Q000502:physiology; D012161:Retinal Artery / Q000503:physiopathology*; D014661:Vasoconstriction / Q000502:physiology
D006442:Glycated Hemoglobin; D010100:Oxygen