A Questionnaire-Derived Prediction Nomogram for Affected Semicircular Canal and Laterality of Benign Paroxysmal Positional Vertigo

<b>Objective</b>: To investigate whether a detailed historical questionnaire can predict the affected semicircular canal and lateralization in patients with benign paroxysmal positional vertigo (BPPV). <b>Methods</b>: In this retrospective study, 459 patients with positional vertigo were evaluated, of whom 236 patients diagnosed with BPPV completed a symptom-based questionnaire. Based on the questionnaire data, logistic regression models were developed to predict lateralization and the affected semicircular canal. The clinical diagnosis of BPPV served as the reference standard. A nomogram was constructed based on the final logistic regression model, and model performance was evaluated using area under the receiver operating characteristic curve (AUC) in both training and validation cohorts. <b>Results</b>: Among 220 BPPV patients included, 152 (69.09%) were diagnosed with posterior semicircular canal BPPV (PSC-BPPV), 49 (22.27%) with horizontal semicircular canal canalolithiasis (HSC-BPPV-can), and 19 (8.64%) with horizontal semicircular canal cupulolithiasis (HSC-BPPV-cup). Waking up, lying down and rotating the head toward the left/right in the supine position, triggering vertigo, were significant predictors of the affected semicircular canal. Rotating the head toward the left/right in the supine position and vertigo duration were significantly predictors for lateralization. The AUCs were 0.787 and 0.714 for lateralization, and 0.814 and 0.842 for canal prediction in training and validation cohorts, respectively. <b>Conclusions</b>: The nomogram demonstrated good consistency with the reference standard diagnoses and may facilitate the identification of the affected side and canal in BPPV.