What is the likely diagnosis for an adult patient with left facial asymmetry, drooling of saliva on the left side, drooping of the left angle corner of the mouth, and left-sided facial numbness, potentially indicating a lacunar infarct (LACI) or another type of infarct?

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Clinical Classification: This is NOT a Lacunar Infarct (LACI)

The clinical presentation of left facial asymmetry with drooling, drooping of the mouth corner, and facial numbness indicates a cortical stroke affecting the facial nerve pathway, most consistent with a Partial Anterior Circulation Infarct (PACI) or Total Anterior Circulation Infarct (TACI), not a lacunar infarct. 1

Why This Cannot Be Classified as LACI

Lacunar Infarcts Present Differently

  • Lacunar infarcts are subcortical strokes <1.5 cm affecting deep penetrating arteries in the basal ganglia, brainstem, or deep white matter 2, 3, 1
  • Patients with true LACI present with classical lacunar syndromes WITHOUT cortical signs: pure motor hemiparesis, pure sensory syndrome, sensorimotor stroke, ataxic hemiparesis, or dysarthria-clumsy hand 1
  • Facial numbness (sensory involvement) combined with facial weakness suggests cortical involvement, which excludes lacunar classification 1

Your Patient's Presentation Suggests Cortical Stroke

  • Facial drooling and mouth drooping indicate facial nerve dysfunction, which when combined with sensory loss points to cortical localization 4
  • The Cincinnati Prehospital Stroke Scale identifies facial droop as one of three key stroke signs, with 72% probability of stroke when any single sign is abnormal 4
  • Motor deficits with sensory signs (facial numbness) distinguish cortical strokes from pure lacunar syndromes 1

Critical Diagnostic Workup Required

Immediate Imaging

  • Non-contrast CT head is mandatory initially to exclude intracranial hemorrhage 2
  • Vascular imaging (CTA or MRA) must be obtained urgently to exclude large vessel occlusion, even when cortical stroke is suspected, because NIHSS scores correlate poorly with large vessel occlusion presence 2, 1
  • MRI is superior to CT for detecting acute cortical infarcts and distinguishing them from chronic lacunar infarcts 1

Cardiac Evaluation is Mandatory

  • Transthoracic echocardiography at minimum and extended cardiac rhythm monitoring are mandatory given the cortical presentation 1
  • Carotid imaging (duplex ultrasound, CTA, or MRA) within 48 hours to exclude ipsilateral large-artery stenosis >50% 2

Critical Management Pitfall to Avoid

Misclassification of stroke subtype has direct therapeutic consequences: a patient with atrial fibrillation and what appears to be a small infarct requires anticoagulation, not just antiplatelet therapy 2, 1. The clinical syndrome alone is insufficient for diagnosis—imaging confirmation of infarct size and location plus exclusion of alternative causes (especially cardioembolic sources) is mandatory 2.

References

Guideline

Clinical Classification of Stroke

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Diagnostic Workup for Lacunar Stroke

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Lacunar Infarcts: Etiology, Diagnosis, and Management

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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