Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0162473 (Frey)
 2,599 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In neurologic examination of patients with a suspected compressive lesion at the thoracic region, the dermatomic level of sensory disturbance is the only index indicating the anatomic level of a lesion. Because spinal cord tumors usually are solitary compressive lesions, the relationship between the anatomic and dermatomic levels is conveniently examined. We examined the relationship between the highest dermatomic level of sensory disturbance and the anatomic level, axial location, and type of spinal cord tumors in the thoracic region in 19 patients (8 men and 11 women aged 27-78 years; 11 neurinomas, 7 meningiomas, 1 neurofibroma). The distribution of sensory disturbance was evaluated with 3-g Frey hair and 1-g pin-prick examinations. The dermatomic distribution of sensory disturbance was diagnosed according to the dermatome chart of Keegan and Garrett. The anatomic level and axial location of the tumor were highly related to the sensory disturbance. Eight of 12 tumors in which the dermatomic level of sensory disturbance was within one vertebral segment of the anatomic level were situated in the middle or lower thoracic region (T6-T10). All five tumors in which the dermatomic level was two or more vertebral segments away from the anatomic level were situated at the conus medullaris (T12) or upper thoracic region (T1-T5); the highest level of sensory disturbance was from 4 to 11 segments below the anatomic level of the tumor. In two patients with no sensory disturbance, the tumor was in the upper thoracic region (T5) and compressed the spinal cord from the dorsal side. When a spinal cord tumor at the thoracic region is suspected, imaging examinations should be performed sufficiently cranially.
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PMID:Relationship between the anatomic and dermatomal levels of spinal cord tumors in the thoracic region. 760 29

The purpose of this study was to examine how pain to punctate mechanical stimuli varies with position within the zone of secondary hyperalgesia. Secondary hyperalgesia was produced by an intradermal injection of capsaicin (50 microg) into the volar forearm of human volunteers (n=9). Before and at 20, 60 and 100 min after the capsaicin injection, a computer-controlled electromechanical stimulator was used to deliver controlled-force stimuli to the skin via a 12-mm wide, 100-microm thick blade probe. Three forces (16, 32 and 64 g; 1 s) were each applied in a random order to 10 sites spaced in 1-cm increments along a line starting 1 cm from the injection site and ending near the wrist. At 40 and 80 min after capsaicin injection the 'zone of hyperalgesia' was determined with use of a hand-held 20-g von Frey probe. Whereas, before capsaicin, the blade probe produced little or no pain, after capsaicin the 32-g and 64-g stimuli evoked pain consistently within but not outside the border of secondary hyperalgesia determined with the von Frey probe. Within the zone of hyperalgesia the average pain ratings to the 64-g stimulus decreased exponentially with distance from the injection site. Surprisingly, the space constant for this exponential decay was large (about 18 cm), and thus the decrease in pain ratings from the center to the edge of the secondary zone was small (37%). However, pain ratings dropped precipitously just outside the zone of secondary hyperalgesia. This finding unlikely reflects a ceiling effect because pain ratings within the zone of secondary hyperalgesia increased linearly with force. The relatively uniform pain ratings to the blade stimuli within the zone of secondary hyperalgesia and the sharp border that delimits the zone of hyperalgesia indicate that this sensory disturbance approaches being an 'all-or-nothing' phenomenon. Thus, a two-state model for central plasticity is needed to explain secondary hyperalgesia.
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PMID:Spatial mapping of the zone of secondary hyperalgesia reveals a gradual decline of pain with distance but sharp borders. 1077 58