title: Peripheral vestibular loss detected in pediatric patients using a smartphone-based test of the subjective visual vertical.
abstract: BACKGROUND
  Detection of peripheral vestibular loss (PVL) in children with dizziness is an important and challenging task. The static subjective visual vertical (SVV) test can effectively detect PVL, but requires specialized equipment.
  
  
  OBJECTIVE
  The goal of this study was to determine the efficacy of a smartphone-based SVV test at detecting PVL in pediatric patients.
  
  
  METHODS
  Thirty-nine patients between 7 and 18 years old (mean=14.0±2.70) underwent conventional SVV (conv-SVV) and smartphone-based SVV (ip-SVV) testing. Subjects included 6 with PVL (based on clinical history and other vestibular tests), 6 with benign paroxysmal positioning vertigo (BPPV), 11 with central causes of vertigo (CV), 8 with non-vestibular dizziness (NVD), and 8 controls.
  
  
  RESULTS
  Mean ip-SVV score in the PVL group (2.77±1.45) was significantly higher than in each of the other groups (BPPV=0.89±0.55; CV=1.08±0.68; NVD=1.45±1.19; Control=1.08±0.73; one-way analysis of variance, p=0.008), and remained significant after adjusting for age and gender by multiple linear regression analysis. Receiver operating characteristic analysis predicted an optimal ip-SVV cut-off score of >2.13° with a sensitivity of 66.7%, specificity of 97.0%, positive predictive value (PPV) of 80%, and negative predictive value of 94.1% for detecting PVL. Sensitivity and PPV improved to 75% and 100%, respectively, when subjects tested >1 month after symptom onset (n=24) were excluded.
  
  
  CONCLUSIONS
  Smartphone-based SVV testing is a simple and useful office-based method for detecting PVL in children with dizziness.
authors.affiliation: The Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; The Department of Otology and Laryngology, Harvard Medical School, 243 Charles Street, Boston, MA 02114, USA. Electronic address: jacob.brodsky@childrens.harvard.edu.
authors.forename: Jacob R
authors.initials: JR
authors.lastname: Brodsky
authors.affiliation: The Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA. Electronic address: brandon.cusick@childrens.harvard.edu.
authors.forename: Brandon A
authors.initials: BA
authors.lastname: Cusick
authors.affiliation: The Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; The Center for Clinical Research, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA. Electronic address: kosuke.kawai@childrens.harvard.edu.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Kawai
authors.affiliation: The Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; The Department of Otology and Laryngology, Harvard Medical School, 243 Charles Street, Boston, MA 02114, USA. Electronic address: margaret.kenna@childrens.harvard.edu.
authors.forename: Margaret
authors.initials: M
authors.lastname: Kenna
authors.affiliation: The Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; The Department of Otology and Laryngology, Harvard Medical School, 243 Charles Street, Boston, MA 02114, USA. Electronic address: guangwei.zhou@childrens.harvard.edu.
authors.forename: Guangwei
authors.initials: G
authors.lastname: Zhou
mesh_terms: D000293:Adolescent; D065635:Benign Paroxysmal Positional Vertigo / Q000150:complications / Q000175:diagnosis*; D016022:Case-Control Studies; D002648:Child; D004244:Dizziness / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D063731:Mobile Applications; D011237:Predictive Value of Tests; D012372:ROC Curve; D000068997:Smartphone; D014724:Vestibular Function Tests / Q000295:instrumentation*; D014796:Visual Perception
keywords: Pediatric vestibular testing; Peripheral vestibular loss; Smartphone; Subjective visual vertical (SVV)