title: Onset of oscillopsia after visual maturation in patients with congenital nystagmus.
abstract: OBJECTIVE
  To describe the clinical and oculographic characteristics of a cohort of five patients with congenital nystagmus (CN) and late-onset oscillopsia caused by a coincidental decline in other visual and/or ocular motor functions.
  
  
  METHODS
  Retrospective, observational, case series.
  
  
  METHODS
  Five visually mature patients with CN and recent-onset oscillopsia were evaluated clinically and with motility recordings.
  
  
  METHODS
  Eye movement analysis was performed off-line by computer analysis of digitized data. Nystagmus was analyzed for null-zone characteristics, waveforms, frequency, amplitudes, and slow-phase drift velocity during foveation. Surgical and medical treatment of associated ocular conditions in four of five patients.
  
  
  METHODS
  Presence of symptomatic oscillopsia and average time during foveation periods of slow-phase drift velocity less than 10 degrees /second.
  
  
  RESULTS
  One of the five patients had associated rod-cone dystrophy, and another had recurrence of childhood head posturing with return of an eccentric null zone. The remaining three patients had decompensated strabismus associated with their oscillopsia. All five patients complained of oscillopsia in primary position that was relieved in the four who received treatment. Treatment included prismatic correction in one patient and surgery in three. Recordings in primary position after treatment showed increased duration during foveation periods of slow-phase drift velocity less than 10 degrees /second and an overall decreased intensity (amplitude/frequency) of the nystagmus.
  
  
  CONCLUSIONS
  Symptomatic oscillopsia in patients with CN is unusual. This visually disturbing symptom can be precipitated by new or changing associated visual sensory conditions (e.g., decompensating strabismus, retinal degeneration). If the associated conditions can be treated, then accompanying oscillopsia may be relieved.
authors.affiliation: Laboratory of Sensorimotor Research, The National Eye Institute, The National Institutes of Health, Building 49 Room 2A50, Bethesda, MD 20892, USA.
authors.forename: R W
authors.initials: RW
authors.lastname: Hertle
authors.forename: E J
authors.initials: EJ
authors.lastname: FitzGibbon
authors.forename: J M
authors.initials: JM
authors.lastname: Avallone
authors.forename: E
authors.initials: E
authors.lastname: Cheeseman
authors.forename: E K
authors.initials: EK
authors.lastname: Tsilou
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D004585:Electrooculography; D005123:Eye / Q000254:growth & development; D005133:Eye Movements; D005139:Eyeglasses; D005260:Female; D006801:Humans; D008297:Male; D009039:Motion Perception; D020417:Nystagmus, Congenital / Q000150:complications*; D015835:Ocular Motility Disorders / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D014792:Visual Acuity