Thalamic or Central Pain States Poststroke

Thalamic or central pain states are generally regarded as rare in stroke, occurring in fewer than 2% of patients. However, a recent study suggests that they may be more common, occurring in up to 8% of unselected stroke patients. Cerebrovascular lesions leading to central pain states do not necessarily involve the thalamus, but can occur following lower brainstem and suprathalamic lesions. Damage to the spinothalamocortical tract appears to be a prerequisite to the development of central poststroke pain (CPSP). Development of CPSP is likely related to denervation hyperexcitability of third or fourth order, thalamic or cortical neurons. Central pain is often described as a 'burning' sensation in association with an unpleasant association of tingling, pins and needles, or numbness. Spontaneous or evoked dysesthesia and allodynia/hyperalgesia are common. Central or thalamic pain is generally intractable to most therapeutic interventions. One case is presented to illustrate the typical clinical presentation of thalamic pain states and the difficulties in treating this pain