Eye Handbook App for OKN
Your browser does not support the video tag.
Identifier
Eye_Handbook_App_for_OKN
Title
Eye Handbook App for OKN
Creator
Olwen Murphy, MD; Daniel R. Gold, DO
Affiliation
(OM) Department of Neurology, The Johns Hopkins School of Medicine, Baltimore, Maryland; (DRG) Departments of Neurology, Ophthalmology, Neurosurgery, Otolaryngology - Head & Neck Surgery, Emergency Medicine, and Medicine, The Johns Hopkins School of Medicine, Baltimore, Maryland
Subject
Eye Handbook App for OKN
Description
Optokinetic nystagmus (OKN): one way this can be examined virtually is using a smartphone application (e.g. Eye Handbook © app used in this video) or optokinetic tape/flag/drum held in front of the examiner's camera. The optokinetic stimulus should occupy the full screen of the patient's device (easier to elicit and appreciate OKN using a computer screen rather than a smartphone). Instruct the patient to move close to their screen, focus on an area of the screen close to the lens of the camera, and count the stripes as they pass. The slow phases represent smooth pursuit while the fast phases represent saccades. Since the optokinetic stimulus used does not involve full visual field stimulation (e.g., looking out the window at passing scenery from a moving train), this is not a true OKN. Situations in which the virtual or bedside examination [https://collections.lib.utah.edu/details?id=1307320 ] of OKN can be helpful include: 1) rapid assessment of symmetry and presence/absence of pursuit/saccades in an uncooperative or difficult to examine patient, 2) it can help to bring out a subtle adduction lag in INO [https://collections.lib.utah.edu/details?id=1278693 ] (3) one of the first ocular motor signs of PSP is loss of the downward fast phase to an optokinetic stimulus directed upward [https://collections.lib.utah.edu/details?id=1290930 ] (4) if nystagmus is seen in a patient with functional monocular (when the good eye is occluded) or binocular blindness, this suggests that the patient has at least some vision, 5) since upward saccades are often affected in dorsal midbrain (Parinaud's syndrome), vertical OKN can demonstrate this and convergence retraction nystagmus (when stimulus is directed downward).
Date
2022
Language
eng
Format
video/mp4
Type
Image/MovingImage
Collection
Neuro-Ophthalmology Virtual Education Library: Dan Gold Collection: https://novel.utah.edu/Gold/
Publisher
North American Neuro-Ophthalmology Society
Holding Institution
Spencer S. Eccles Health Sciences Library, University of Utah
Rights Management
Copyright 2016. For further information regarding the rights to this collection, please visit: https://NOVEL.utah.edu/about/copyright
ARK
ark:/87278/s63g3z08
File Name
Eye_Handbook_App_for_OKN.mp4
Setname
ehsl_novel_gold
ID
1757566
Reference URL
https://collections.lib.utah.edu/ark:/87278/s63g3z08