Application In Chronic Inflammatory Demyelinating Polyradiculoneuritis With Contact Heat Evoked Potentials

Chronic inflammatory demyelinating polyradiculoneuritis(CIDP) is a chronic disease progresses of peripheral neuropathy. Etiology is unclear. The pathological changes in segmental demyelinated, nerve fibers onion skin samples change. Its diagnostic criteria mainly include the following content:(1) the clinical characteristics (2) electrical physiology characteristic (3) phil bowel nerve biopsy pathological feature (4) cerebrospinal fluid characteristics.Because of the damage and fear,the last two are difficult to finish.the Electric physiology of non-invasive, simplicity and repeatability and the abnormal rate 96% above, make it become the dominant instrument CIDP diagnosis. At present commonly used clinically acupuncture check nociceptive obstacles, but this check is affected by patients subjective factors and consciousness, lacking of convenient, greatly influenced objective evaluation methods. The traditional sensory nerve conduction velocity and evoked potentials (seps) can only activate crude fibre——Aαfiber and Aβfiber, failed to excited conduction pain myelinated fibers Aδand without delta pith C fibers. Laser although can selectively stimulate A delta fiber and C fiber, but limitations, such as activated receptor number less, may burn skin, etc. Contact heat evoked potentials is a new neurologic electrophysiologic examination, which can excite thin myelinated Aδfibers and unmyelinated C fibers, reflect the disorder of pain and warm pathway objectively.Objective:To study the characteristics of nociceptive system inchronic inflammatory demyelinatingpolyradiculoneuritis(CIDP) byContactHeatEvoked Potentials(CHEPs), and evaluate the CHEPs in the Electrophysiological diagnosis of CIDP.Methods:Twenty-one definite CIDP patient and thirty-twosex-,height-and age-matched heathy controls were included in this study.Thermal stimuli was applied at 51℃intensity level at four sites:C7,volar surface of the foream,the skin of leg at 5cm proximal to the medial malleolus and lumbar part.The CHEPs were recorded from Cz.The latency of the evoked potential were recorded.The CV of Aδfibers of peripheral nerves and N-wave ltencies were analyzed.The nerve conduction velocity (NCV include MCV and SCV)of the limbs were also evaluated.Results:(1) CHEPs were elicited reliably and stably in all controls,but only76.19% preference in the CIDP.(2)The visual analogues (VAS)for pain perception was higher incontrols(upperlimbs:7.50 and lower limbs:7.25)as compared to CIDPcomplication withhypoesthesia(upper limbs:6.0 and lower limbs:6.0) (Z=-3.934,-3.763,both P< 0.05)(3)The conduction velocity of Aδfibers in upper and lower limbs in the paitents was significantly reduced compared to the controls [(7.296±3.183m/s)vs(13.792±5.672 m/s); (5.422±3.242 m/s) vs (13.145±7.963 m/s), respectively,t=3.478,3.464, bothP<0.05].(4) fourteen out of twenty-one(66.67%) had slow CV of Aδfibers in upper limb,but compared with lower limbs, nineteen out of twenty-one (90.48%) had slow CV of Aδfibers (P=0.037).(5)In the CIDP, upper and lower limbs proximal stimulation of CHEPS waveform, N-wavelatency group is extended, but this was not statistically significant, But distal N-wave incubation period is extended, control was statistically significant (P=0.001, P=0.000)(6)In the CIDP, nineteen out of twenty-one (90.48%)had slow CV of Aδfibers,vs thirteen out of twenty-one (61.90%)has slow MCV,vs fifteen out of twenty-one(71.43%)has slow SCV,CIDP have higher abnormality rates in CHEPs than MCVand SCV(χ2=4.17 P<0.05,χ2=2.25 P>0.05).Conclusions:1.Normal control group CHEPs can stable, reliable derivations, because of nociceptive fiber damaged or pain pathways exist lesions central in some patients CIDP patients fail to elicit the exact waveform.2.CIDP patients have obvious nociceptive transmission damage, thus to pain stimulation insensitive. This also reflects CHEP can record the objective reaction, pain can selectively activate skin harmful sensors and objective evaluation pain pathways situation, found that the thermal pain small fiber lesions.3.CIDP patients' upper and lower limbs feel symmetry limbs motion fibrous nvolvement, and with the double lower limbs for him.4.CIDP patients peripheral nociceptive small fiber is definite damage, proximal neural pathway (nerve root, the ridge QiuShu and cortex) no specific damage, and peripheral nerve lower limbs CHEP check more meaningful.5.CHEPS can find lesions, and clinical under SCV and MCV appear when a false negatie. CHEPS still can reflect nociceptive fiber damage, but as early diagnosis of reference index.