title: Exercise-induced visual loss associated with advanced glaucoma in young adults.
abstract: OBJECTIVE
  To highlight the phenomenon of exercise-induced visual loss associated with advanced glaucoma and to discuss the possible underlying mechanisms.
  
  
  METHODS
  Three young adult patients with congenital or juvenile-onset glaucoma presenting with visual loss which occurred during exercise underwent ophthalmic examination. In 2 cases, visual function parameters, including visual fields (Humphrey full threshold perimetry) were measured before and after exercise.
  
  
  RESULTS
  All patients clearly described visual loss during exercise. In the 2 cases in which data were available, significant impairment in central visual acuity and reduced foveal sensitivity and mean deviation on visual field analysis occurred during exercise of mild to moderate intensity with complete or near complete recovery of visual function upon cessation of exercise.
  
  
  CONCLUSIONS
  Young patients with advanced glaucomatous optic neuropathy should be questioned regarding exercise-induced visual disturbance. We hypothesise that a 'vascular steal' is the likely mechanism underlying this phenomenon. Patients should be advised to limit activities which induce their symptoms, and therapeutic measures to promote ocular blood flow should be considered.
authors.affiliation: Birmingham and Midland Eye Centre, City Hospital NHS Trust, Birmingham, UK.
authors.forename: P
authors.initials: P
authors.lastname: Shah
authors.forename: K W
authors.initials: KW
authors.lastname: Whittaker
authors.forename: A P
authors.initials: AP
authors.lastname: Wells
authors.forename: P T
authors.initials: PT
authors.lastname: Khaw
mesh_terms: D000328:Adult; D015444:Exercise; D005260:Female; D005902:Glaucoma, Open-Angle / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology; D015354:Vision, Low / Q000209:etiology* / Q000503:physiopathology; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields / Q000502:physiology