As discussed in detail by Dagnelie (2008) and others

(Chen et al., 2009a), tools for prosthetic vision assessment should permit the quantification of implant performance across a variety of domains, ranging from simple light, direction and motion perception, to improvements in the ability of recipients to complete routine daily tasks such as obstacle avoidance, self-grooming and food preparation. As recently highlighted by Rizzo and Ayton (2014), a key concern in this context is the lack of standard tests and scoring systems, limiting the ability of researchers to compare results. Recipients of the early Brindley (Brindley and Rushton, 1974) and Dobelle (Dobelle et al., 1976) cortical implants were assessed in terms of their ability to read Braille characters RGFP966 supplier and conventional letters. Later iterations of the Dobelle system were tested using more conventional tools such as Landolt rings and Snellen charts, with which the visual acuity of one implant recipient was estimated at 20/1200, achieved via head scanning

(Dobelle, 2000). Since Dobelle׳s last publication in the scientific literature, there have been no further reports of visual acuity or functional performance testing in cortical visual prosthesis recipients. Conversely, the development and subsequent implantation in humans Palbociclib solubility dmso of retinal devices has enabled the application of newer testing paradigms to patients experiencing real-world prosthetic vision. For example, recipients of the Alpha IMS (Stingl et al., 2013) and Argus II (da Cruz et al., 2013 and Dorn et al., 2013) retinal implants have been assessed using a variety of visual acuity tests including the Basic Assessment of Light and SPTLC1 Motion (BALM) (Bach et al., 2010 and Wilke

et al., 2007) and Basic Grating Acuity (BaGA) (Wilke et al., 2007) tests, Landolt rings, individual letters and words of 2–4 letters in length or motion of high-contrast rectangles on computer screens. Stingl et al. (2013) also reported on the recipients׳ experiences with activities of daily living (ADL), such as recognition and location of objects, and navigating the environment, with one recipient achieving poor ADL results, despite satisfactory tests of visual acuity. Notably, the authors report that recipients for whom positive results were obtained on the ADL tasks described the ADL improvements as the most rewarding benefit provided by the implant (Stingl et al., 2013). Direct translation of the applicability of these vision scoring techniques to cortical implant recipients may be complicated by differences in the nature of cortical vs. retinal prosthetic vision.