13.13.2 Central post-stroke pain (CPSP)

Identification: Male patient, 68 years old, 6 months post-right thalamic ischemic stroke, with chronic pain in the left hemibody. History of Present Illness: Initial Event (Stroke): Type: Ischemic stroke in the territory of the right thalamoperforating artery Acute Symptoms: Left-sided hemi-hypoesthesia Mild ataxia No motor deficit Current Pain: Location: Left arm and leg (80%) Left face (20%) Characteristics: Continuous: Deep burning (7/10 VAS) Exacerbations: Electric shocks (9/10), 10-20 episodes/day Neuropathic Phenomena: Allodynia to light touch (clothing, wind) Hyperpathia to percussion Evolution: Onset 2 weeks post-stroke Progressive worsening, refractory to common analgesics Physical/Neurological Examination: Sensory: Thermal and pain hypoesthesia in the left hemibody Mechanical hyperesthesia (von Frey brush 4.31) Motor/Coordination: Preserved strength (5/5) Mild left-sided dysdiadochokinesia Reflexes: Ipsilateral hyperreflexia (Babinski sign present) Complementary Exams: Brain MRI (FLAIR/Diffusion): Ischemic sequela in the right thalamus (ventral posterior lateral nucleus) Absence of new infarcts Electroneuromyography: Normal (excludes peripheral neuropathy) Somatosensory Evoked Potentials: Absence of N20 potential on the left