Measurement of Retinal Blood Flow Volume by Laser Speckle Flowgraphy Before and After Arteriovenous Sheathotomy for Branch Retinal Vein Occlusion

Abstract

Purpose: : To use laser speckle flowgraphy (LSFG) to quantitatively evaluate the effect of arteriovenous sheathotomy on blood flow volume in an eye with branch retinal vein occlusion (BRVO).

Methods: : LSFG can measure the relative blood flow volume through retinal vessels in a living eye both quantitatively and non-invasively. The fixed quantity of the relative flow volume was determined by the square blur rate (SBR), an index of the flow velocity. A 63-year-old female was referred to our clinic with a diagnosis of BRVO, OD. The best corrected visual acuity (BCVA) of LogMAR had declined to -0.40, OD. A vitrectomy with arteriovenous sheathotomy at the arteriovenous crossing site was performed on the right eye. A restoration of downstream blood flow by reperfusion could be observed during the operation, after the arteriovenous sheathotomy. The relative blood flow volume through the retinal vein proximal to the arteriovenous crossing site was measured by LSFG within 24 hours before the surgery and on day 7 after the surgery, and the pre- and postoperative results were compared.

Results: : The postoperative SBR through the retinal vein reperfused with arteriovenous sheathotomy increased by 29.4% compared to the preoperative SBR. At 3 months after the surgery, the BCVA of LogMAR improved to -0.15, OD.

Conclusions: : LSFG might be useful to quantitatively evaluate whether the arteriovenous sheathotomy is successful in decompressing the mechanical pressure in the arteriovenous crossing site of BRVO and improving the blood flow volume in the retinal vein.

Keywords: vascular occlusion/vascular occlusive disease • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • vitreoretinal surgery