人工臓器 最近の進歩 Hiroyuki KANDA, Takashi FUJIKADO 1. はじめに 2. 視覚のなり立ち 図 1 10 著者連絡先 565-0871 2-2 E-mail. kanda@sensory.med.osaka-u.ac.jp 1 3. 視覚障害 Quality of Life QOL 2 1 1 12 18 1 25.5 2 21.0 3 8.8 1) 1 51 New estimates of visual impairment and blindness: 2010, WHO 202 41 3 2012
図 1 4. 視覚系における人工臓器 Intraocular Lens IOL Visual Prosthesis 1 phosphene 2) 3) 4) 5) 14) 4 Retinal Prosthesis 4 5. 人工網膜 5) 図 2 phosphene 5 7 mm m 図 3 phosphene 41 3 2012 203
図 2 図 3 0.5 mm 49 3 mm 15) 6. 人工網膜の研究動向 1990 2000 1) 南カリフォルニア大学 Second Sight 社グループ Humayun Second Sight Epi-retinal Stimulation 図 4A 2002 Argus, Second Sight 16 6 6 6) Argus Second Sight Argus 602006 Argus 30 6 2.7 7) phosphene 0.016 15 cm 3 m QOL FLORA Functional Low-vision Obser ver Rated Assessment 66.7 positive effect 8) 30 3 30 3 30 3 7) Humayun CEEU Argus 204 41 3 2012
図 4 3 A Epi-retinal Stimulation B Sub-retinal Stimulation C Suprachoroidal-transretinal Stimulation STS 2) チュービンゲン大学 Retina Implant 社グループ Zrenner Retina Implant Sub-retinal Stimulation 図 4B Alpha IMS chip Retinal Implant LSI Alpha IMS chip 1500 9) 2005 18 0.036 4 5 cm Alpha IMS chip 3) 日本グループ 2001 Suprachoroidal-transretinal Stimulation STS 図 4C STS 10) 14) STS 2004 20084 13) STS phosphene 2 9 2010 2 14) phosphene 49 7. おわりに 2011 Second Sight FDA 41 3 2012 205
文献 1) 17 2006, 263-7 2) Dobelle WH: Artificial vision for the blind by connecting a television camera to the visual cortex. ASAIO J 46: 3-9, 2000 3) Pezaris JS, Reid RC: Simulations of electrode placement for a thalamic visual prosthesis. IEEE Trans Biomed Eng 56: 172-8, 2009 4) Veraar t C, Raftopoulos C, Mor timer JT, et al: Visual sensations produced by optic nerve stimulation using an implanted self-sizing spiral cuff electrode. Brain Res 813: 181-6, 1998 5) Weiland JD, Cho AK, Humayun MS: Retinal prostheses: current clinical results and future needs. Ophthalmology 118: 2227-37, 2011 6) Humayun MS, Weiland JD, Fujii GY, et al: Visual perception in a blind subject with a chronic microelectronic retinal prosthesis. Vision Res 43: 2573-81, 2003 7) Humayun MS, Dorn JD, da Cruz L, et al: Interim results from the inter national trial of Second Sight s visual prosthesis. Ophthalmology 119: 779-88, 2012 8) Dorn JD, Geruschat D, Dagnelie G, et al: Functional vision and quality of life of Argus (R) II Retinal Prosthesis System users as measured by the Functional Low-vision Observer Rated Assessment (FLORA). Invest Ophthalmol Vis Sci 53: E-Abstract 5511, 2012 9) Zrenner E, Bartz-Schmidt KU, Benav H, et al: Subretinal electronic chips allow blind patients to read letters and combine them to words. Proc Biol Sci 278: 1489-97, 2011 10) Kanda H, Morimoto T, Fujikado T, et al: Electrophysiological studies of the feasibility of suprachoroidal-transretinal stimulation for artificial vision in normal and RCS rats. Invest Ophthalmol Vis Sci 45: 560-6, 2004 11) Sakaguchi H, Fujikado T, Fang X, et al: Transretinal electrical stimulation with a suprachoroidal multichannel electrode in rabbit eyes. Jpn J Ophthalmol 48: 256-61, 2004 12) Nakauchi K, Fujikado T, Kanda H, et al: Transretinal electrical stimulation by an intrascleral multichannel electrode array in rabbit eyes. Graefes Arch Clin Exp Ophthalmol 243: 169-74, 2005 13) Fujikado T, Morimoto T, Kanda H, et al: Evaluation of phosphenes elicited by extraocular stimulation in normals and by suprachoroidal-transretinal stimulation in patients with retinitis pigmentosa. Graefes Arch Clin Exp Ophthalmol 245: 1411-9, 2007 14) Fujikado T, Kamei M, Sakaguchi H, et al: Testing of semichronically implanted r etinal prosthesis by suprachoroidal-transretinal stimulation in patients with retinitis pigmentosa. Invest Ophthalmol Vis Sci 52: 4726-33, 2011 15) Santos A, Humayun MS, de Juan E Jr, et al: Preservation of the inner retina in retinitis pigmentosa. A morphometric analysis. Arch Ophthalmol 115: 511-5, 1997 206 41 3 2012