title: Pseudo-Monocular Nystagmus Associated with Duane's Syndrome: Report of Two Cases.
abstract: OBJECTIVE
  To present clinical findings and eye movement recordings of two children who had clinically apparent monocular nystagmus.
  
  
  METHODS
  Full orthoptic and ophthalmological examination and eye movement recordings.
  
  
  RESULTS
  An 8-year-old girl (patient 1) and a 13-month-old girl (patient 2) presented with right monocular nystagmus and right esotropia. A magnetic resonance imaging (MRI) scan of the brain obtained previously had been unremarkable for patient 2. Patient 1 had right amblyopia with visual acuity (VA) reduced to 20/400. Both patients had left abduction deficit and left palpebral fissure narrowing on adduction indicative of Duane's retraction syndrome. Patient 2 also had mild enophthalmos. Both patients had constant horizontal nystagmus in the right eye and very fine nystagmus in the left eye, which could only be detected on video and eye movement recordings.
  
  
  CONCLUSIONS
  The existence of Duane's syndrome in both patients was masking the presence of nystagmus in the left eye, highlighting that detailed examination in this case can eliminate the need for neuroimaging. Interestingly, the dominant eye of both patients was on the side which was affected by Duane's syndrome, as there was less nystagmus in this eye.
authors.affiliation: a Newcastle University, The Medical School , Newcastle upon Tyne , United Kingdom .
authors.forename: Simona E
authors.initials: SE
authors.lastname: Constantinescu
authors.affiliation: b University of Leicester Ulverscroft Eye Unit, Leicester Royal Infirmary , Leicester , United Kingdom , and.
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: McLean
authors.affiliation: c Consultant Ophthalmologist, Hull and East Yorkshire Eye Hospital, NHS Trust , United Kingdom.
authors.forename: James
authors.initials: J
authors.lastname: Innes
authors.affiliation: b University of Leicester Ulverscroft Eye Unit, Leicester Royal Infirmary , Leicester , United Kingdom , and.
authors.forename: Irene
authors.initials: I
authors.lastname: Gottlob
mesh_terms: D002648:Child; D004370:Duane Retraction Syndrome / Q000150:complications*; D005133:Eye Movements / Q000502:physiology; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D009759:Nystagmus, Pathologic / Q000175:diagnosis / Q000209:etiology*; D014792:Visual Acuity / Q000502:physiology
keywords: Duane’s syndrome; nystagmus; pseudo-monocular nystagmus