Autonomic and thermal sensory symptoms and dysfunction after stroke.

Abstract

Symptoms interpreted as unilateral disturbances of autonomic function, such as coldness, dryness, sweating, and trophic changes, are well known but incompletely understood clinical problems after stroke. The present study provides data related to the incidence and mechanisms behind such symptoms. Temperature perception thresholds, skin temperatures, evaporation rates, and skin blood flow responses were measured bilaterally in 37 stroke patients aged 58 +/- 13 years (mean +/- SD) and in a control group of 15 patients aged 64 +/- 15 years with a single transient ischemic attack. Of the 37 stroke patients, 43% reported a sensation of coldness in the contralesional side of the body. Basal skin blood flow and temperature were relatively lower in the contralesional side. There was an excess of evaporation in the contralesional side after brain stem lesions and in the ipsilesional side after hemispheric lesions. Vasomotor reflex asymmetries occurred in 34% of the patients and were due to weak vasodilator or vasoconstrictor reflexes in the ipsilesional side. These abnormalities correlated significantly to sensations of unilateral coldness, hypalgesia, and thermohypesthesia in the contralesional side and anatomically to lesions in spinothalamo-cortical pathways. Focal central nervous system lesions due to stroke may result in symptoms and measurable evidence of unilateral disturbance of skin sympathetic function. Vasomotor asymmetries are probably due to lesions of vasomotor pathways descending uncrossed. Subjective coldness may be due to disturbed central processing.