Structural and Electrophysiologic Outcomes in a Patient with Retinal Metallosis.
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ABSTRACT:
SUBMITTER: Sulewski ME
PROVIDER: S-EPMC5942906 | biostudies-literature | 2018 Feb
REPOSITORIES: biostudies-literature
Publications
Structural and Electrophysiologic Outcomes in a Patient with Retinal Metallosis.
Sulewski Michael E ME Serrano Leona W LW Han Grace G Aleman Tomas S TS Nichols Charles W CW
Ophthalmology. Retina 20170928 2
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Project description:ObjectivesThe objectives of this study were to demonstrate the safety of auditory brainstem implant (ABI) surgery and document the subsequent development of auditory and spoken language skills in children without neurofibromatosis type II (NFII).DesignA prospective, single-subject observational study of ABI in children without NFII was undertaken at the University of North Carolina at Chapel Hill. Five children were enrolled under an investigational device exemption sponsored by the investigators. Over 3 years, patient demographics, medical/surgical findings, complications, device mapping, electrophysiologic measures, audiologic outcomes, and speech and language measures were collected.ResultsFive children without NFII have received ABIs to date without permanent medical sequelae, although 2 children required treatment after surgery for temporary complications. All children wear their device daily, and the benefits of sound awareness have developed slowly. Intra-and postoperative electrophysiologic measures augmented surgical placement and device programming. The slow development of audition skills precipitated limited changes in speech production but had little impact on growth in spoken language.ConclusionsABI surgery is safe in young children without NFII. Benefits from device use develop slowly and include sound awareness and the use of pattern and timing aspects of sound. These skills may augment progress in speech production but progress in language development is dependent upon visual communication. Further monitoring of this cohort is needed to better delineate the benefits of this intervention in this patient population.
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Project description:We developed and characterized a canine model of outer retinal degeneration induced by sodium iodate (SI) intravitreal injection after vitrectomy. In the preliminary study, we repeatedly injected SI intravitreally into the eyes of three canines to develop outer retinal degeneration two weeks after vitrectomy. Based on the preliminary study, a single dose of either 1.2 mg or 1.0 mg SI/0.05 mL was also injected (1.2 mg in n = 5 canines, 1.0 mg in n = 2 canines). Spectral domain-optical coherence tomography (OCT), electroretinography (ERG), and histological examinations were performed at baseline and following intravitreal injection. In the preliminary study, after a 0.5-mg SI injection and a 1.0-mg SI injection and after two 0.8-mg SI injections, retinal degeneration with retinal thinning was observed on OCT imaging. In the second study, after a single 1.0- or 1.2-mg SI injection, outer retinal degeneration was induced. All eyes showed diffuse outer retinal degeneration on OCT and a loss of both cone and rod responses in ERG. Histological examination also showed the loss of outer retinal layer. Intravitreally injected SI (1.0-1.2 mg) in a vitrectomized canine model induced outer retinal degeneration effectively, and could be evaluated through in vivo ophthalmic examination.
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