title: The sensitivity of the bielschowsky head-tilt test in diagnosing acquired bilateral superior oblique paresis.
abstract: OBJECTIVE
  To determine the sensitivity of the Bielschowsky head-tilt test and other commonly used criteria in identifying patients with true bilateral superior oblique paresis.
  
  
  METHODS
  A retrospective chart review was performed to identify patients seen between 1978 and 2009 who were diagnosed with acquired bilateral superior oblique paresis.
  
  
  METHODS
  All patients had a confirmed history of head trauma or brain surgery with altered consciousness followed by symptomatic diplopia. Bilateral superior oblique paresis was defined and diagnosed by the above history, including the presence of greater extorsion in downgaze than upgaze on Lancaster red-green testing, a V-pattern strabismus, and bilateral fundus extorsion. We analyzed findings of the Bielschowsky head-tilt test, the Parks 3-step test, and reversal of the hypertropia from straight-ahead gaze to the other 8 diagnostic positions of gaze to determine these tests' sensitivity in identifying true bilateral superior oblique paresis.
  
  
  RESULTS
  Twenty-five patients were identified with the diagnosis of true bilateral superior oblique paresis. The Bielschowsky head-tilt test had a 40% sensitivity, the Parks 3-step test had a sensitivity of 24%, and reversal of the hypertropia had a sensitivity of 60% in making the diagnosis of true bilateral superior oblique paresis.
  
  
  CONCLUSIONS
  What previously has been described as masked bilateral superior oblique paresis simply may be a reflection of inherent poor sensitivity of the Bielschowsky head-tilt test, the Parks 3-step test, and reversal of the hypertropia in diagnosing bilateral superior oblique paresis. Hence, none of these tests should be relied on exclusively to make this diagnosis.
authors.affiliation: The Krieger Children's Eye Center at The Wilmer Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland. Electronic address: brinda.muthusamy@gmail.com.
authors.forename: Brinda
authors.initials: B
authors.lastname: Muthusamy
authors.affiliation: The Krieger Children's Eye Center at The Wilmer Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Kristina
authors.initials: K
authors.lastname: Irsch
authors.affiliation: The Krieger Children's Eye Center at The Wilmer Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Han-Ying
authors.initials: HY
authors.lastname: Peggy Chang
authors.affiliation: The Krieger Children's Eye Center at The Wilmer Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: David L
authors.initials: DL
authors.lastname: Guyton
mesh_terms: D000328:Adult; D003941:Diagnostic Techniques, Ophthalmological / Q000592:standards; D004172:Diplopia / Q000175:diagnosis*; D005260:Female; D016489:Head Injuries, Closed / Q000150:complications; D006801:Humans; D008297:Male; D009801:Oculomotor Muscles / Q000473:pathology*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013285:Strabismus / Q000175:diagnosis*; D020432:Trochlear Nerve Diseases / Q000175:diagnosis*; D015348:Vision, Binocular