Abstract
Purpose: :
After branch retinal vein occlusion (BRVO), the retinal territory affected by the occlusion becomes hypoxic and the arterioles crossing this territory are often constricted. The purpose of the current experimental animal study is to investigate the effect of intravitreal juxta-arteriolar microinjection of L-lactate on the retinal arteriolar diameter following acute BRVO in minipigs.
Methods: :
Under general anesthesia, 6 eyes of 6 minipigs were evaluated. Argon laser endo-photocoagulation was used to create BRVO. Two hours after BRVO, an intravitreal juxta-arteriolar microinjection of 50 µl L-lacate 1 mM (pH=7.4) was performed. The procedure was recorded in real time and retinal arteriolar diameter changes were measured in vivo using a Retinal Vessel Analyzer.
Results: :
Two hours after BRVO there was a 6.0 ± 2.8 % decrease in the study retinal arteriolar diameter compared to baseline. An increase of 29.8 ± 16.0 % and of 23.2 ± 9.2 % (p<0.05) of the retinal arteriolar diameter was evidenced 10 and 25 minutes, respectively, after L-lactate microinjection compared to the diameter prior to L-lactate microinjection.
Conclusions: :
We measured a significant vasodilation after intravitreal juxta-arteriolar L-lactate microinjection in eyes with experimental BRVO. L-lactate microinjection can be of potential interest in acute BRVO, reversing the arteriolar vasoconstriction, thus leading to increase of the retinal arteriolar blood flow and possibly to improvement of the retinal cellular function in the occluded territory.
Keywords: retina • blood supply • vascular occlusion/vascular occlusive disease