Posterior circulation stroke diagnosis in unselected group of acutely dizzy patients

Backgrounds: Diagnostics of a posterior circulation ischemia (POCI) in patients with acute vertigo is a challenging task. Recently, the combination of HINTS (Head Impulse, Nystagmus and Test of Skew) exam and ABCD2 has been recommended to identify stroke in these patients. Until now, studies regarding HINTS have mostly been tested on preselected patient groups and their results are only partially applicable to real clinical practice.

Aims: To compare the sensitivity and specificity of HINTS and ABCD2 and their combination in unselected acutely dizzy patients in the emergency department (ED) toward posterior circulation stroke detection.

Methods: A prospective cross-sectional monocentric study in ED patients with acute onset of dizziness lasting less than 72 h. Their clinical characteristics, HINTS, vascular risk factors, ABCD2 scores and neuroimaging data were analyzed.

Results: 140 patients were recruited. Acute stroke was identified by MRI in 39 patients. All patients had central pattern nystagmus, skew deviation or further focal neurological finding. The age (≥60) and arterial hypertension clearly distinguished stroke and non-stroke group (p < 0001). The sensitivity of HINTS, ABCD2 and their combination in the unselected group was high (82,1 - 97,4%), but specificity low. After removing patients with inconclusive diagnosis, including transitory ischemic attack, specificity was much higher and comparable to previously published results.

Conclusions: The sensitivity and specificity of HINTS in previously published studies may vary because of their selection criteria. Even though, our study was performed on the unselected patient cohort, combination of HINTS and ABCD2 remained highly sensitive in detecting POCI and outperformed each of these tests alone.