Zero on the NIHSS does not equal the absence of stroke

Abstract

Study objective: The National Institutes of Health Stroke Scale (NIHSS) measures deficits caused by a stroke, but not all stroke signs are captured on the NIHSS. We determine the symptoms and stroke localization of patients with brain infarction and an NIHSS score of 0.

Methods: We studied all patients who presented with acute neurologic symptoms to our stroke center from 2004 to 2008 and had persistent symptoms at the evaluation in the emergency department, an NIHSS score of 0, and an infarct on diffusion-weighted imaging. We characterized the symptoms, signs, lesion location, demographics, and stroke causes.

Results: Twenty patients met inclusion criteria. Symptoms frequently experienced were headache, vertigo, and nausea. The posterior circulation was commonly infarcted in this group. Truncal ataxia was the most common neurologic sign.

Conclusion: Ischemic stroke may cause symptoms that are associated with no deficits on the NIHSS score.