Spatial summation of thermal stimuli assessed by a standardized, randomized, single-blinded technique

Scandinavian Journal of Pain - Tập 9 - Trang 81-86 - 2015
Vibe Maria Rasmussen1, Catarina Ellehuus-Hilmersson2, Per Rotbøll-Nielsen3, Mads Utke Werner3
1Department of Anesthesia, Vejle Sygehus/Sygehus Lillebælt, Kabbeltoft 25, DK 7100 Vejle, Denmark
2Department of Internal Medicine, University Hospital of Skåne, SE 221 85 Lund, Sweden
3Multidisciplinary Pain Center, Rigshospitalet, Copenhagen University Hospitals, Blegdamsvej 9, DK 2100 Copenhagen Ø, Denmark

Tóm tắt

Abstract Background and aims Quantitative sensory testing of thermal perception (QTT) is a valuable method in clinical and experimental assessment of the function of small nerve fibres. Previous studies have indicated existence of spatial summation for warmth, cool and heat pain stimulation, but study designs and assessment methods have not always been mutually consistent. The aims of this study were, first, to examine spatial summation of QTT by differently sized contact thermodes, and, second, to evaluate if these differences are significant from a clinical and scientific perspective. Methods Sixteen healthy subjects were included. Warmth detection (WDT), cool detection (CDT) and heat pain (HPT) thresholds were assessed in random order, with the stimulation areas of the contact thermodes of 3.0, 6.3 and 12.5 cm2, blinded to the subjects. Assessments were made bilaterally at volar part of the distal arm and medial part of the lower leg. Data analyses were by a mixed model with random effect for subject and fixed-effects for the variables, site (arm/leg), thermode area (ln thermode area) and side (dominant/non-dominant), in addition to conventional pairwise non-parametric comparisons. Results Data from 2 subjects were excluded. In the remaining 14 subjects only 4 subjects were able to identify the correct sequence of thermode sizes. The model demonstrated highly statistical significant relationships regarding main effects: thermode area (P < 0.0001) and stimulation site (P < 0.0001; except for CDT P = 0.011). The only significant interaction was between thermode area*site (P = 0.005) for CDT. The study demonstrated in 17 of 18 possible comparisons between thermode size and stimulation site, a significant spatial summation for WDT, CDT and HPT. Conclusion This randomized, single-blind study of thermal thresholds demonstrated spatial summation and that considerable deviations may occur if values obtained with differing thermode sizes are used uncritically. Implications Data from the present study enable interpolation of thermal thresholds with differing thermode sizes, facilitating comparisons across studies.

Tài liệu tham khảo

Neziri AY, Scaramozzino P, Andersen OK, Dickenson AH, Arendt-Nielsen L, Cura-tolo M. Reference values of mechanical and thermal pain tests in a pain-free population. Eur J Pain 2011;15:376–83. Backonja MM, Walk D, Edwards RR, Sehgal N, Moeller-Bertram T, Wasan A, Irving G, Argoff C, Wallace M. Quantitative sensory testing in measurement of neuropathic pain phenomena and other sensory abnormalities. Clin J Pain 2009;25:641–7. Walk D, Sehgal N, Moeller-Bertram T, Edwards RR, Wasan A, Wallace M, Irving G, Argoff C, Backonja MM. Quantitative sensory testing and mapping: a review of nonautomated quantitative methods for examination of the patient with neuropathic pain. Clin J Pain 2009;25:632–40. Lautenbacher S, Nielsen J, Andersen T, Arendt-Nielsen L. Spatial summation of heat pain in males and females. Somatosens Mot Res 2001;18:101–5. Defrin R, Urca G. Spatial summation of heat pain: a reassessment. Pain 1996;66:23–9. Nielsen J, Arendt-Nielsen L. Spatial summation of heat induced pain within and between dermatomes. Somatosens Mot Res 1997;14:119–25. Hilz MJ, Stemper B, Schweibold G, Neuner I, Grahmann F, Kolodny EH. Quantitative thermal perception testing in 225 children and juveniles. J Clin Neurophysiol 1998;15:529–34. Greenspan JD, Thomadaki M, McGillis SL. Spatial summation of perceived pressure, sharpness and mechanically evoked cutaneous pain. Somatosens Mot Res 1997;14:107–12. Quantitative sensory testing: a consensus report from the Peripheral Neuropathy Association. Neurology 1993;43:1050–2. Dyck PJ, O’Brien PC. Quantitative sensation testing in epidemiological and ther-apeutic studies of peripheral neuropathy. Muscle Nerve 1999;22:659–62. Hagander LG, Midani HA, Kuskowski MA, Parry GJ. Quantitative sensory testing: effect of site and skin temperature on thermal thresholds. Clin Neurophysiol 2000;111:17–22. Hilz MJ, Stemper B, Axelrod FB, Kolodny EH, Neundorfer B. Quantitative thermal perceptiontesting in adults. J Clin Neurophysiol 1999;16:462–71. Hilz MJ, Glorius S, Beric A. Thermal perception thresholds: influence of determination paradigm and reference temperature. J Neurol Sci 1995;129: 135-40. Riley III JL, Robinson ME, Wise EA, Myers CD, Fillingim RB. Sex differences in the perception of noxious experimental stimuli: a meta-analysis. Pain 1998;74:181–7. Rolke R, Baron R, Maier C, Tolle TR, Treede RD, Beyer A, Binder A, Birklein F, Bötefur IC, Braune S, Flor H, Huge V, Klug R, Landwehrmeyer GB, Mageri W, Malhöfner C, Rolko C, Schaub C, Scherens A, Sprenger T, Valet M, Wasserka B. Quantitative sensory testing in the German Research Network on Neuropathic Pain (DFNS): standardized protocol and reference values. Pain 2006;123:231–43. Rolke R, Magerl W, Campbell KA, Schalber C, Caspari S, Birklein F, Treede RD. Quantitative sensory testing: a comprehensive protocol for clinical trials. Eur J Pain 2006;10:77–88. Pfau DB, Geber C, Birklein F, Treede RD. Quantitative sensory testing of neuropathic pain patients: potential mechanistic and therapeutic implications. Curr Pain Headache Rep 2012;16:199–206. Werner MU, Perkins FM, Holte K, Pedersen JL, Kehlet H. Effects of gabapentin in acute inflammatory pain in humans. Reg Anesth Pain Med 2001;26: 322-8. Pedersen JL, Kehlet H. Hyperalgesia in a human model of acute inflammatory pain: a methodological study. Pain 1998;74:139–51. Tobin J. Estimation of relationships for limited dependent variables. Econometrica 1958;26:24–36. Greenspan JD. Quantitative assessment of neuropathic pain. Curr Pain Headache Rep 2001;5:107–13. Verdugo R, Ochoa JL. Quantitative somatosensory thermotest. A key method for functional evaluation of small calibre afferent channels. Brain 1992;115:893–913. Dyck PJ, Zimmerman I, Gillen DA, Johnson D, Karnes JL, O’Brien PC. Cool, warm, and heat-pain detection thresholds: testing methods and inferences about anatomic distribution of receptors. Neurology 1993;43:1500–8. Pedersen JL, Kehlet H. Secondary hyperalgesia to heat stimuli after burn injury in man. Pain 1998;76:377–84.