Retina-Vitreous
2019 , Vol 28 , Num 4
Clinical Results in Visual Prosthesis and Current Status
Prof Dr, FEBO, Acıbadem M.A Aydınlar Üniversitesi Tıp Fakültesi, Göz Hastalıkları ABD, Maslak, İstanbul - Türkiye
Inner retinal neurons are shown to be relatively maintained in diseases causing degeneration in outer retinal layers,like retinitis pigmentosa,or
age-related macular degeneration which cause severe visual loss,and do not have a defi nite treatment yet.Thus,visual prosthesis can be used in
these diseases.The aim of visual prosthesis is to obtain phospenes,and useful vision by electrically stimulating neurons of the visual pathways.
First studies started with obtaining,and localizing phospenes following stimulation of visual cortex,and the clinical use increased with the
development of retinal prosthesis. Retinal prosthesis were studied in epiretinal,subretinal,and suprachoroidal locations.The first and the only
prosthesis with 10-years of clinical experience is Argus II Retinal Prosthesis System(RPS).It has been implanted over 400 patients with outer
retinal dystrophy who had vision before,but lost severely to the level of light perception,and resulted in increased quality of life by enabling detection
of motion,identifi cation and localisation of shapes,and objects,reading big letters,self-mobilization,and performing daily life activities
more easily.The best visual aquity obtained with this system is 20/1262 in only some of the patients,not being able to correct legal blindness
yet.Despite positive,and safe clinical results experienced with epiretinal Argus II RPS,due to its limitations in indication of use,its production
has been ceased by September 2019.Instead,ORIONÒ cortical prosthesis is being actively studied,as it has the potential capacity to be used in a
wider range of patients with very low vision.The experience gained as a result of trials of a lot of prosthesis that are studied,and left is valuable
in development of new generation prosthesis.As a result of increased clinical experiences,and progresses in technology,with the development
of better softwares,increased ease of use,and implanting different types of prosthesis,visual prosthesis can help more patients with low vision
in the future.
Keywords :
Age related macular degeneration, Argus II, phosphene, retinitis pigmentosa, visual prosthesis