Neuroscience · Year 2 · from Neuroscience
Case 2: Lacunar Stroke - Pure Motor Hemiparesis
Patient Presentation
Demographics: 71-year-old female
Chief Complaint: Right arm and leg weakness noticed upon awakening
History of Present Illness: The patient went to bed feeling well but woke this morning with weakness affecting her right arm and leg equally. She has no facial weakness, no speech difficulty, and no numbness. She has a long history of hypertension (often not taking medications consistently) and type 2 diabetes.
Physical Examination:
- Vital signs: BP 168/94, HR 72, T 36.8C
- General: Comfortable, conversant
Neurological Examination:
- Mental status: Alert, oriented, cognition intact
- Language: Fluent, intact naming, comprehension, and repetition - NO APHASIA
- Cranial nerves:
- Visual fields: Full - NO HEMIANOPIA
- Face: Mild right lower facial weakness
- All others intact
- Motor:
- Right upper extremity: 3/5 throughout (deltoid, biceps, triceps, grip)
- Right lower extremity: 3/5 throughout (hip flexors, knee extension, ankle)
- Left side: 5/5
- Sensory: INTACT to light touch, pinprick, and proprioception bilaterally - NO SENSORY DEFICIT
- Reflexes: Right side 3+, left side 2+; right Babinski present
- Coordination: Unable to assess right side due to weakness; left normal
- Gait: Unable to walk without assistance
Key Observation: Pure motor deficit without cortical signs (no aphasia, no neglect, no hemianopia, no sensory loss)
Imaging:
- CT head: No hemorrhage; no early ischemic changes
- MRI brain with DWI: Small (12 mm) focus of restricted diffusion in the left posterior limb of the internal capsule
Workup:
- HbA1c: 8.9%
- LDL: 145 mg/dL
- ECG: Normal sinus rhythm
- Echocardiogram: Normal; no cardioembolic source
Diagnosis: Lacunar infarct of left posterior limb of internal capsule - Pure motor hemiparesis syndrome
Treatment:
- Aspirin 81 mg daily
- High-intensity statin (atorvastatin 80 mg)
- Blood pressure optimization (goal <130/80)
- Diabetes management with endocrinology referral
- Physical therapy for gait training and strengthening
- No thrombolysis/thrombectomy (small vessel disease, not large vessel occlusion)
Clinical Course: The patient's strength gradually improved over 4-6 weeks. At 3-month follow-up, she had 4+/5 strength in right extremities and was walking independently. Blood pressure was controlled at 128/78, and HbA1c had improved to 7.4%.
Clinical Pearl: Lacunar infarcts result from small vessel disease (lipohyalinosis) affecting penetrating arteries, typically in the setting of chronic hypertension. They produce characteristic clinical syndromes: pure motor hemiparesis (most common - posterior limb of internal capsule or pons), pure sensory stroke (thalamus), ataxic hemiparesis, and dysarthria-clumsy hand. The absence of cortical signs (aphasia, neglect, visual field cut) is the key diagnostic feature. Treatment focuses on aggressive vascular risk factor management rather than thrombolysis/thrombectomy, as the occlusion involves small perforating vessels.