title: Chronic implantation of newly developed suprachoroidal-transretinal stimulation prosthesis in dogs.
abstract: OBJECTIVE
  To investigate the feasibility of implanting a newly developed suprachoroidal-transretinal stimulation (STS) prosthesis in dogs and to determine its biocompatibility and stability over a 3-month period.
  
  
  METHODS
  The STS prosthesis system consisted of an array of 49 electrodes (nine were active), an intravitreal return electrode, and an extraocular microstimulator. The 49-electrode array was implanted into a scleral pocket of each of three healthy beagle dogs. Color fundus photography, fluorescein angiography, electroretinography, and functional testing of the STS system were performed postoperatively. The dogs were euthanatized 3 months after the implantation, and the retinas were evaluated histologically.
  
  
  RESULTS
  All the prostheses were successfully implanted without complications, and no serious complications occurred during the 3-month postoperative period. The fixation of the implant was stable throughout the experimental period. Fluorescein angiography showed that the entire retina, including the area on the electrode array, remained well perfused without intraocular inflammation. Electroretinograms recorded from the eyes with the prosthesis did not differ significantly from those recorded from control eyes. Functional testing of the STS system showed that this system performed well for the 3-month experimental period. Histologic evaluations showed good preservation of the retina over the electrode array.
  
  
  CONCLUSIONS
  Implantation of a newly developed STS retinal prosthesis into a scleral pocket of beagle dogs is surgically feasible and can be performed without significant damage to the retina or the animal. The biocompatibility and stability of the system were good for the 3-month observation period.
authors: Department of Applied Visual Science, Osaka University Graduate School of Medicine, Suita City, Osaka, Japan. takeshi.morimoto@ophthal.med.osaka-u.ac.jp
authors: Takeshi
authors: T
authors: Morimoto
authors: Motohiro
authors: M
authors: Kamei
authors: Kentaro
authors: K
authors: Nishida
authors: Hirokazu
authors: H
authors: Sakaguchi
authors: Hiroyuki
authors: H
authors: Kanda
authors: Yasushi
authors: Y
authors: Ikuno
authors: Haruhiko
authors: H
authors: Kishima
authors: Tomoyuki
authors: T
authors: Maruo
authors: Kunihiko
authors: K
authors: Konoma
authors: Motoki
authors: M
authors: Ozawa
authors: Kohji
authors: K
authors: Nishida
authors: Takashi
authors: T
authors: Fujikado
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D002829:Choroid / Q000601:surgery*; D004195:Disease Models, Animal; D004285:Dogs; D004558:Electric Stimulation / Q000295:instrumentation; D004596:Electroretinography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D005654:Fundus Oculi; D008297:Male; D011474:Prosthesis Design; D019919:Prosthesis Implantation / Q000379:methods*; D012160:Retina / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D012174:Retinitis Pigmentosa / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D013997:Time Factors; D016896:Treatment Outcome; D057488:Visual Prosthesis
chemical_list: D001672:Biocompatible Materials