Hemorrhagic bleeding into the thalamus, typically resulting from hypertension.
Thalamic hemorrhage causes a variety of neurological findings, most commonly contralateral hemianesthesia (numbness), mild hemiparesis, hemiataxia, and sometimes intolerable intractable severe dysesthetic pain in half of the body (previously called "Dejerine-Roussy syndrome" or "thalamic pain," but now called "central poststroke pain"). Because the thalamus is involved, sensory symptoms tend to predominate. Onset is usually during activity. Specific symptoms depend on the size and specific location of the hemorrhage, but can include stupor, coma, and signs of elevated intracranial pressure in their most severe forms. Virtually, any type of focal neurological change can be seen. Interestingly, while the motor and sensory deficits noted above are most common, oculomotor findings occur and even mild aphasia, cognitive deficits, and neurobehavioral dysfunction