Functional visual loss

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.

A Case of Functional (Psychogenic) Monocular Hemianopia Analyzed by Measurement of Hemifield Visual Evoked Potentials

“…The term ‘functional’ visual loss is used to describe symptomatic visual changes that cannot be explained by any physiologic findings [5]. Other terms, i.e.…”

“…It can also be a functional disorder; however, affected individuals then experience a monocular defect without objective evidence of visual pathway damage [3, 4, 5]. The measurement of visual evoked potentials (VEPs) is a valuable tool for the evaluation of sensory activity in the visual pathway from the retina to the occipital cortex.…”

Tip of iceberg: when unusual vision complaints with a normal examination prompt a closer look

“…Regardless of the severity of the patient's clinical presentation, several studies have shown that the most effective management of NOVL is reassurance and follow-up [6,13,[16][17][18]. Psychotherapy is rarely indicated and has not been shown to improve outcome [2,14,15].…”

Non‐organic visual loss in children: prospective and retrospective analysis of associated psychosocial problems and stress factors

“…The diagnosis of NOVL is based on inconsistency in a wide range of visual function tests and is confirmed by the objective measurement with pattern‐onset visual‐evoked potentials (pVEPs) and by the normalization of symptoms at follow‐up (Schindler et al. ; Lim et al. ; McBain et al.…”

“…A high level of suspicion is important because the early diagnosis and follow‐up of NOVL minimizes excessive referrals and unnecessary health care (Schindler et al. ; Chen et al. ).…”