ABSTRACT
Published databases of quantitative sensory testing (QST) for sensory thresholds provide a means for detecting deficits of the thermonociceptive sensory nervous system. These databases, however, do not assist in the assessment of neuropathic pain, which is characterized by pain or hyperalgesia, or both. We utilized the method of levels for innocuous thermal stimuli, warm and cool, and the method of limits for noxious thermal stimuli, hot pain and cold pain, to determine QST thresholds. Stimuli were applied to distal and proximal sites in the upper and lower limbs of 50 healthy volunteers, ranging in age from 19 to 59 years. Thresholds for innocuous and noxious stimuli in this study were similar to previously published results. The mean pain rating across all sites at thresholds for noxious heat and cold stimuli was 4.10, as rated on a 0-10 numeric scale. Suggestions are provided for combining threshold information for innocuous and noxious stimuli and related pain ratings for the evaluation of sensory nervous system function and, specifically, neuropathic pain.
Subject(s)
Neuralgia/physiopathology , Nociceptors/physiology , Pain Measurement/methods , Pain Threshold/physiology , Peripheral Nervous System Diseases/physiopathology , Adult , Afferent Pathways/physiology , Afferent Pathways/physiopathology , Central Nervous System/physiology , Central Nervous System/physiopathology , Cold Temperature/adverse effects , Female , Hot Temperature/adverse effects , Humans , Hyperalgesia/diagnosis , Hyperalgesia/physiopathology , Male , Middle Aged , Neuralgia/diagnosis , Peripheral Nerves/physiology , Peripheral Nerves/physiopathology , Peripheral Nervous System Diseases/diagnosis , Physical Stimulation/methods , Thermosensing/physiologyABSTRACT
PURPOSE: To assess the presence, extent, and clinical correlates of quantitative MR volumetric abnormalities in ipsilateral and contralateral hippocampus, and temporal and extratemporal lobe regions in unilateral temporal lobe epilepsy (TLE). METHODS: In total, 34 subjects with unilateral left (n = 15) or right (n = 19) TLE were compared with 65 healthy controls. Regions of interest included the ipsilateral and contralateral hippocampus as well as temporal, frontal, parietal, and occipital lobe gray and white matter. Clinical markers of neurodevelopmental insult (initial precipitating insult, early age of recurrent seizures) and chronicity of epilepsy (epilepsy duration, estimated number of lifetime generalized seizures) were related to magnetic resonance (MR) volume abnormalities. RESULTS: Quantitative MR abnormalities extend beyond the ipsilateral hippocampus and temporal lobe with extratemporal (frontal and parietal lobe) reductions in cerebral white matter, especially ipsilateral but also contralateral to the side of seizure onset. Volumetric abnormalities in ipsilateral hippocampus and bilateral cerebral white matter are associated with factors related to both the onset and the chronicity of the patients' epilepsy. CONCLUSIONS: These cross-sectional findings support the view that volumetric abnormalities in chronic TLE are associated with a combination of neurodevelopmental and progressive effects, characterized by a prominent disruption in ipsilateral hippocampus and neural connectivity (i.e., white matter volume loss) that extends beyond the temporal lobe, affecting both ipsilateral and contralateral hemispheres.
