[Permanent hemispheric pain syndrome due to traumatic cortico-subcortical lesions in the left hemisphere]

Pain due to cortical-subcortical lesions may be paroxystic or permanent. The latter may be strictly similar to that derived from the selective involvement of the thalamic ventroposterior nucleus. We report a 21 year-old right handed patient who in a cranial-encephalic injury had a counter-stroke lesion of the left parietal-temporal-frontal region, demonstrated by magnetic resonance imaging (MRI), and who remained in coma for 2 weeks. At 6 weeks the patients began to have continuous burning algias in the right hemisome with hyperpathy, allodynia, etc., with exacerbations. Treatment attempted to elevate the levels of brain serotonin was followed by partial improvement. Likewise, the patient presented certain aphasic disturbances and showed different coordination synkinesis, etc., of the right side. The somato-sensitive evoked potentials (PE) were normal. A review of the literature is undertaken emphasizing the rarity with which algic pictures by cortical-subcortical lesions appear in lesions of the dominant hemisphere. Special emphasis is made in the concept of "deafferentation", particularly developed during the last decade (Albe-Fessard, Tasker, Leijon, Boivie). Following the suggestions of Albe-Fessard, the possibility of a central algogenic mechanism by "retrograde" deafferentation (interference in the thalamic-cortical loops) of the median thalamus (unspecific nuclei or of diffuse projection) as a consequence of the cortical-subcortical lesion (of an outstanding form, probably of the parietal operculum) is suggested.