Itemized NIHSS subsets predict positive MRI strokes in patients with mild deficits

Area of Science:

• Neurology
• Medical Imaging
• Stroke Diagnosis

Background:

• Diffusion-weighted imaging (DWI) is crucial for ischemic stroke diagnosis but can be negative in up to 25% of patients.
• Identifying predictors of MRI-positive stroke from the National Institutes of Health Stroke Scale (NIHSS) is essential for accurate diagnosis.

Purpose of the Study:

• To identify predictors of MRI-positive stroke using itemized NIHSS scores in patients with mild neurological deficits.
• To develop a predictive score for DWI positivity in mild stroke cases.

Main Methods:

• Analysis of data from the Stroke Warning Information and Faster Treatment study (2006-2010).
• Inclusion of patients with mild deficits (NIHSS 0-5) and confirmed stroke diagnosis.
• Multivariate logistic regression to assess factors predicting DWI-positive strokes.

Main Results:

• 28.0% of patients with stroke undergoing MRI were DWI negative.
• Predictors of DWI positivity included NIHSS scores of 3-5, motor deficits, ataxia, and absence of sensory deficits.
• A novel NIHSS-m score was developed to predict DWI positivity in mild strokes without neglect or visual field deficits.

Conclusions:

• Itemized NIHSS score subsets effectively predict DWI positivity in mild ischemic strokes.
• The presence of neglect or visual field deficits on NIHSS is highly indicative of an MRI-positive stroke, even with low NIHSS scores.