Reconstruction of the four-layered retinal vasculature and elucidation of the mechanism of retinal nonperfusion based on blood cell hemodynamics

Research Project

Project/Area Number	18K16925
Research Category	Grant-in-Aid for Early-Career Scientists
Allocation Type	Multi-year Fund
Review Section	Basic Section 56060:Ophthalmology-related
Research Institution	Kyoto University
Principal Investigator	Muraoka Yuki 京都大学, 医学研究科, 助教 (00739089)
Project Period (FY)	2018-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000) Fiscal Year 2019: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000) Fiscal Year 2018: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Keywords	網膜循環 / 網膜無灌流 / 糖尿病網膜症 / 網膜静脈閉塞症 / 毛細血管瘤 / 光干渉断層計血管造影 / 補償光学 / 補償光学レーザー検眼鏡 / 網膜血管 / 黄斑部 / 生体 / OCTA / 網膜無灌流領域
Outline of Final Research Achievements	In human retina, photoreceptors exist in the retinal outer layer, and are fed by choroidal circulation behind the retinal outer layer. In contrast, the bipolar- and retinal ganglion cells locate in the retinal inner layer, and are fed by the retinal circulation in the retinal inner layer. Histologically, the retinal vasculature has three dimensional vascular plexuses of 3-4 layers. Until now, clinicians had evaluated the retinal vasculature changes mainly using fluorescein angiography (FA). However, the FA, can not reveal each vascular plexus due to the low resolution. In this study, we succeeded in imaging the each vascular plexus using high resolution optical coherence tomography angiography and adaptive optics scanning light ophthalmoscope with the axial and traverse resolution of 3 um, and could differentiate the four layers of the retinal vascular network in living human retina and appreciate the well-regulated retinal microcirculation in each plexus.
Academic Significance and Societal Importance of the Research Achievements	網膜循環に関する代表的な疾患として、糖尿病網膜症や網膜静脈閉塞症がある。また、これら疾患に共通する重要な病態として、網膜無灌流がある。この病態は、一度生じると不可逆かつ高度な視機能障害を引き起こすので、この病態の形成メカニズムの解明が必須である。本研究では、高解像度の新しいイメージング手法を用いて、非常に細かいレベルで網膜血管構造を解像することができ、網膜微小循環に関する新しい生理、また今までわからなかった病態の解明にとって有用な知見を得た。