Comparison of LEP and QST and their contribution to standard sensory diagnostic assessment of spinal lesions: a pilot study
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This study evaluates the additional use of laser-evoked potentials (LEP) and quantitative sensory testing (QST) in the sensory assessment of spinal lesions. Four consecutive patients with spinal lesions verified by MRI and clinical evidence for mild spinothalamic tract involvement were included. The electrophysiological workup [somatosensory evoked potentials (SEP) and LEP] was compared to QST. Electrophysiology and QST were reassessed after about 6 months. LEP detected impaired spinothalamic tract function in 7/8 examinations. QST pointed to spinothalamic tract lesions by loss of thermal function (3/8); most frequent positive sensory signs (3/8) were paradoxical heat sensations. LEP and QST results were concordant in 6/8 examinations. SEPs were abnormal in 2/8 examinations. Congruent results between SEP and both LEP and QST were obtained in 3/8 examinations. LEP detected more deficits than any single QST parameter or their combination but additional QST allows the detection of positive sensory signs. The diagnostic gain of SEP was limited.
KeywordsQuantitative sensory testing (QST) Laser-evoked potentials (LEP) Diagnostic assessment Spinal lesion Spinothalamic tract Neuropathic pain
This work was supported by the “Deutsche Forschungsgemeinschaft” (BI 579/1 and 579/4; Tr236/13-4), the “Bundesministerium für Bildung und Forschung” (DFNS; grant: 01EM0506), the “Kalkhof-Rose-Stiftung” and the “Arbeitsgemeinschaft für Krebsbekämpfung der Träger der gesetzlichen Kranken- und Rentenversicherung NRW”. Thanks to G. Schatt for expert technical assistance.
Conflict of interest
The authors report no conflict of interest.
- 14.Treede RD (1994) Evoked potentials related to pain. In: Boivie J, Hansson P, Lindblom U (eds) Touch, Temperature, and pain in health and disease: mechanisms and assessments. Progress in Pain Research and Management, vol 3. IASP Press, Seattle, WA, pp 473–489Google Scholar