Central nystagmus plus ABCD² identifying stroke in acute dizziness presentations

Area of Science:

• Neurology
• Emergency Medicine
• Diagnostic Imaging

Background:

• Dizziness is a common presenting complaint in emergency departments.
• Differentiating stroke from other causes of dizziness is critical for timely treatment.
• The Head Impulse-Nystagmus-Test of Skew (HINTS) and ABCD² score are established tools for stroke assessment.

Purpose of the Study:

• To evaluate the combined diagnostic ability of the HINTS exam and ABCD² score for identifying cerebrovascular causes of acute dizziness.
• To determine the utility of these tools in an emergency department (ED) setting.

Main Methods:

• Prospective recruitment of 85 patients with acute onset dizziness.
• Analysis of clinical characteristics, ABCD² scores, HINTS findings, and neuroimaging (MRI).
• Comparison of diagnostic accuracy between stroke and non-stroke groups.

Main Results:

• Acute stroke was confirmed in 21 of 85 patients via MRI.
• Patients with stroke had significantly higher mean ABCD² scores (4.0 vs. 2.5).
• HINTS demonstrated 100% sensitivity and 87% specificity for stroke in patients with nystagmus.
• Combining central nystagmus with an ABCD² score ≥4 achieved 100% sensitivity for cerebrovascular causes.
• In patients without nystagmus, an ABCD² score ≥4 prioritized cerebrovascular diagnoses.

Conclusions:

• HINTS effectively differentiates stroke from non-stroke in symptomatic patients.
• The combination of central nystagmus and ABCD² score ≥4 is practical for ED use.
• Cerebrovascular events should be prioritized in patients with ABCD² score ≥4, even without central nystagmus on initial exam.