Peripheral vestibular loss detected in pediatric patients using a smartphone-based test of the subjective visual vertical

Abstract

IntroductionDetection 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. ObjectiveThe goal of this study was to determine the efficacy of a smartphone-based SVV test at detecting PVL in pediatric patients. MethodsThirty-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. ResultsMean 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. ConclusionSmartphone-based SVV testing is a simple and useful office-based method for detecting PVL in children with dizziness.