title: The scotogenic contact lens: a novel device for treating binocular diplopia.
abstract: Binocular diplopia is a debilitating visual symptom requiring immediate intervention for symptomatic control, whether or not definitive treatment is eventually possible. Where prismatic correction is infeasible, the current standard is occlusion, either by a patch or an opaque contact lens. In eliminating one problem-diplopia-occlusive techniques invariably create another: reduced peripheral vision. Crucially, this is often unnecessary, for the reduced spatial resolution in the periphery limits its contribution to the perception of diplopia. Here, we therefore introduce a novel soft contact lens device that instead creates a monocular central scotoma inversely mirroring the physiological variation in spatial acuity across the monocular visual field, thereby suppressing the diplopia with minimal impact on the periphery. We compared the device against standard eye patching in 12 normal subjects with prism-induced binocular diplopia and 12 patients with binocular diplopia of diverse causes. Indexed by self-reported scores and binocular perimetry, the scotogenic contact lens was comparably effective in eliminating the diplopia while significantly superior in acceptability and its impact on the peripheral visual field. This simple, inexpensive, non-invasive device may thus be an effective new tool in the treatment of a familiar but still troublesome clinical problem.
authors: AP-HP, Service d'Ophtalmologie, Hôpital Universitaire Necker-Enfants Malades, Paris, France COGNAC-G, UMR 8257, CNRS-IRBA-Université Paris Descartes, Sorbonne Paris Cité, France.
authors: Matthieu P
authors: MP
authors: Robert
authors: Faculty of Medicine, Imperial College London, London, UK.
authors: Fabrizio
authors: F
authors: Bonci
authors: Faculty of Medicine, Imperial College London, London, UK.
authors: Anand
authors: A
authors: Pandit
authors: Faculty of Medicine, Imperial College London, London, UK Western Eye Hospital, Imperial College Healthcare NHS Trust, London, UK.
authors: Veronica
authors: V
authors: Ferguson
authors: Faculty of Medicine, Imperial College London, London, UK Institute of Neurology, UCL, London, UK.
authors: Parashkev
authors: P
authors: Nachev
mesh_terms: D000328:Adult; D001458:Bandages; D003263:Contact Lenses, Hydrophilic; D004172:Diplopia / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011795:Surveys and Questionnaires; D015348:Vision, Binocular / Q000502:physiology*; D058609:Visual Field Tests; D014794:Visual Fields
keywords: Contact lens; Field of vision; Treatment other; Visual perception