A patient has pure hemisensory loss (face, arm, trunk, leg equally) with no motor or cerebellar findings. MRI shows a small infarct. The most likely location of the lesion is:

• A Posterior limb of internal capsule
• B Parietal operculum
• C Ventral posterolateral (VPL) thalamic nucleus ✓
• D Lateral medulla

Explanation

Pure hemisensory stroke with complete involvement of face, arm, trunk, and leg without motor deficit localizes to the thalamus — specifically the VPL (for body) and VPM (for face) nuclei. A small lacunar infarct in VPL/VPM produces contralateral hemianesthesia affecting all modalities equally. The posterior limb of the internal capsule carries corticospinal and thalamocortical fibers; a lesion there typically produces combined sensorimotor loss. The parietal operculum lesion causes cortical sensory loss (astereognosis, graphesthesia). Lateral medullary lesion causes crossed pattern (ipsilateral face, contralateral body) with pain/temperature dissociation.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.