Supplementary file 1_Diagnostic challenges in posterior circulation ischemic stroke presenting with acute dizziness and vertigo.docx

Because PCS frequently presents with non-specific, fluctuating, or isolated vestibular symptoms, it is about three times more likely to be initially missed in emergency care than anterior circulation stroke (ACS), with important consequences for acute treatment, secondary prevention, and patient outcomes.

Diagnostic evaluation is further complicated by the low sensitivity of prehospital stroke scales for posterior fossa syndromes, the under-representation of PCS deficits on the National Institutes of Health Stroke Scale (NIHSS), and the limited early sensitivity of non-contrast computed tomography (NCCT) and diffusion-weighted magnetic resonance imaging (DWI-MRI) in the posterior fossa. In contrast, structured bedside assessment can improve recognition when applied by trained clinicians.