Ashley is a Christchurch-born first year medical registrar working for the Canterbury District Health Board. She graduated from the Dunedin School of Medicine in 2017, after completing high school in Montreal, Canada. She enjoys long walks on the beach and frozen margaritas.
The Differentiation Of Central And Peripheral Causes Of Vertigo
Electronic documentation of 532 patients under the stroke team from September 2019 to June 2020 was reviewed to identify patients who had initial symptoms of vertigo to form an audit population of 50. Demographic features, diagnostic imaging, results of HINTs/DHP assessment, and risk factors for central causes of vertigo (as determined by Chen et al. in their 2018 study on a new POCI risk scoring system (1)) underwent prevalence comparison between the 4 clinical groups – radiology confirmed POCI, suspected POCI without radiological evidence, peripheral vertigo, and other non-central causes.
There were overall low rates of HINTs testing (Head Impulse 34%; Nystagmus 94%; Test of Skew 28%) and DHP (18%), with poor predictive value (0-36%). Features that were more frequently associated with central causes of vertigo included AF without anticoagulation, previous TIA/strokes, diabetes, speech difficulty, altered limb sensation and limb ataxia. The alternative scoring system proposed by Chen et al. was not valid in this population sample.
HINTs and DHP testing are used infrequently in vertigo differentiation and have low diagnostic association. Increased HINTs/DHP screening is needed to accurately assess their validity and if this remains insufficient, alternative methods need to be considered in order to appropriately screen vertigo patients while avoiding unnecessary imaging.
Chen, R., Su, R., Deng, M., Liu, J., Hu, Q., & Song, Z. (2018). A posterior circulation ischemia risk score system to assist the diagnosis of dizziness. Journal of Stroke and Cerebrovascular Diseases, 27(2), 506-512.