title: [Two cases of digitalis toxicity with reversible and severe decrease of visual acuity].
abstract: BACKGROUND
  We performed electrophysiologic tests on two patients with digitalis toxicity who first had photophobia and xanthopsia and revealed reversible reduced visual acuity and binocular central scotoma.
  
  
  METHODS
  The patients were a 72-year-old male and a 54-year-old male who had symptoms of digitalis toxicity.
  
  
  RESULTS
  The corrected visual acuity was severely decreased during digitalis toxicity, 0.02 oculus dexter (OD) and 0.1 oculus sinister (OS) in case 1 and 0.04 OD and 0.2 OS in case 2. But visual acuity recovered as the blood levels of digitalis decreased to the normal level and the corrected visual acuity was 0.7 OD and 0.8 OS in case 1 and 0.8 OD and 0.9 OS in case 2. We recorded 30 Hz-flicker electroretinogram (ERG), single flash ERG, photopic ERG, and scotopic ERG when digitalis blood levels were elevated and normal. Decreased amplitudes of 30 Hz-flicker ERG and photopic ERG suggested that photoreceptor function was disturbed at digitalis toxicity and cone dysfunction was more severely disturbed than rod dysfunction.
  
  
  CONCLUSIONS
  30 Hz-flicker ERG, as well as electrocardiogram and digitalis blood level, is a relatively convenient and useful measure of digitalis toxicity. It is necessary consiler toxicity when severe visual dysfunction is observed in patients with digitalis therapy.
authors.affiliation: Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Nagai
authors.forename: H
authors.initials: H
authors.lastname: Ohde
authors.forename: Y
authors.initials: Y
authors.lastname: Betsuin
authors.forename: S
authors.initials: S
authors.lastname: Matsukura
authors.forename: K
authors.initials: K
authors.lastname: Kigasawa
authors.forename: Y
authors.initials: Y
authors.lastname: Mashima
authors.forename: Y
authors.initials: Y
authors.lastname: Oguchi
mesh_terms: D000368:Aged; D004077:Digoxin / Q000506:poisoning*; D004596:Electroretinography; D006801:Humans; D008297:Male; D008875:Middle Aged; D012607:Scotoma / Q000139:chemically induced; D014792:Visual Acuity / Q000187:drug effects*
chemical_list: D004077:Digoxin