Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, 466-8560, Japan.
Department of Ophthalmology, Akita University Graduate School of Medicine, 1-1-1 Hondou, Akita, 010-8543, Japan.
Sci Rep. 2021 Oct 8;11(1):20034. doi: 10.1038/s41598-021-99572-7.
We aimed to investigate the increase in resistivity of the retinal artery in the branch retinal vein occlusion (BRVO)-affected area, and to visualize it. Thirty-two eyes of 32 patients with BRVO were measured by laser speckle flowgraphy (LSFG). The retinal artery and vein running to the BRVO-affected area and vertically symmetrical vessels in the unaffected area were examined. We applied the LSFG parameter beat strength over mean blur rate (BOM), calculated using a similar method to the pulsatility index used in Doppler flowmetry to evaluate resistivity of the vessels. Our results showed that the BOM map could clearly visualize the increase of resistivity in the retinal artery as a two-dimensional map. The BOM of the arteries in the affected area was significantly higher than that of the unaffected area (P = 0.001). Multiple regression analysis showed that the ratio of BOM in retinal arteries of the affected area to the unaffected was significantly associated with the extent of retinal hemorrhage (β = 0.447, P = 0.009). In conclusion, the index of resistivity of the retinal artery in the BRVO-affected area was higher and could be visualized in a two-dimensional map. These findings and techniques would contribute to elucidate the pathophysiology of BRVO.
我们旨在研究视网膜分支静脉阻塞（BRVO）受累区视网膜动脉电阻率的增加，并对其进行可视化。通过激光散斑血流仪（LSFG）测量了 32 例 BRVO 患者的 32 只眼。检查了流向 BRVO 受累区的视网膜动脉和静脉以及不受影响区垂直对称的血管。我们应用了 LSFG 参数搏动强度与平均模糊率的比值（BOM），该参数是使用类似于多普勒血流仪中使用的搏动指数的方法计算的，用于评估血管的电阻率。我们的结果表明，BOM 图可以清晰地将视网膜动脉电阻率的增加可视化成二维图。受累区动脉的 BOM 明显高于未受累区（P=0.001）。多元回归分析显示，受累区视网膜动脉的 BOM 与视网膜出血程度显著相关（β=0.447，P=0.009）。总之，BRVO 受累区视网膜动脉的电阻率指数较高，并可以在二维图中进行可视化。这些发现和技术将有助于阐明 BRVO 的病理生理学。
