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Updated: Aug 29, 2026

Dynamic Visual Tests to Identify and Quantify Visual Damage and Repair Following Demyelination in Optic Neuritis Patients
Published on: April 14, 2014
Functional Visual Loss
Kenneth S. Shindler1, Steven L. Galetta, Nicholas J. Volpe
1Department of Ophthalmology, Scheie Eye Institute, Presbyterian Medical Center, 51 North 39th Street, Philadelphia, PA 19104, USA. ksshindl@aol.com
Abstract:
Patients who present with visual loss that cannot be explained by organic lesions represent a wide spectrum of patients from those with no physiologic problem to those patients who have a true underlying condition. Regardless of where a patient falls within this spectrum, all patients need to be approached with a clinical evaluation to ensure that no underlying physiologic deficit exists. After excluding organic causes with appropriate examination and testing, a patient's visual loss still should not be labeled as functional until it is proven that they can see better than they claim to see. Only after convincingly demonstrating better vision can the physician begin to consider treatment options to help the patient's vision recover. Although functional visual loss places the physician in an unusual adversarial position of refuting a patient's symptoms, exposing the patient in a confrontational manner rarely helps. Instead, an approach that allows patients to resolve the symptoms on their own through reassurance and support often leads to successful restoration of vision. Reassurance that their condition is not serious, and may recover with time, allows patients to slowly admit their vision is improving without ever suggesting that the concern and medical attention they sought was unwarranted.
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