糖尿病患者周围神经传导速度的研究

目的:通过周围神经传导速度(NCV)的研究,早期诊断糖尿病(DM)患者的糖尿病性周围神经病变。方法:应用上海海军医学研究所NDI-200F神经电检诊仪,对DM组95例患者行尺神经、正中神经、胫神经和腓神经运动传导速度(MCV)及尺神经、正中神经、腓肠神经感觉传导速度(SCV)检测与30例健康人组对照。结果:DM组95例, NCV异常率为77.89%(74/95)。共检测665条神经,MCV380条,异常率55.26%,SCV285条,异常率50.88%,差异无显著性意义(P>0.05)。上肢检测380条神经,异常率45.53%,下肢检测285条神经,异常率63.86%,差异有显著性意义(P<0.05)。DM组SCV波幅减低率为53.66%。DM组按病程分为三组,<5年,30例,异常率28.10%;≥5年,31 例,异常率为54.84%;≥10年,34例,异常率74.37%,组间差异均有非常显著性意义(P<0.01)。DM组中29例无周围神经病变症状与体征,NCV异常11例(37.93%)。结论:周围神经传导速度检测不但可以早期诊断糖尿病患者的糖尿病性周围神经病变,而且此方法可靠、简便、无创。     

Correlation of vibratory quantitative sensory testing and nerve conduction studies in patients with diabetes

Monitoring the course of diabetic peripheral neuropathy (DPN) remains a challenge. Besides clinical examination, nerve conduction studies (NCS) and quantitative sensory testing (QST) are the most commonly used methods for evaluating peripheral nerve function in clinical trials and population studies. In this study the correlation between vibratory QST and NCS was determined. Patients (N = 227) with diabetes mellitus participated in this multicenter, single-visit, cross-sectional study. QST of vibration measured with the CASE IV system was compared with a composite score of peroneal motor and tibial motor NCS and with individual attributes of peroneal, tibial, and sural nerves. The correlation between QST and composite score of NCS was 0.234 (Pearson correlation coefficient, P = 0.001). The correlations between QST and individual attributes of NCS ranged from 0.189 to 0.480 (Pearson correlation coefficients, P < 0.001). The low to moderate correlation between QST and NCS suggests that these tests cannot replace each other but are complementary.     

Motor and sensory conduction in the musculocutaneous nerve.

Motor and sensory conduction velocity in the musculocutaneous nerve were determined in 51 normal subjects. The maximal velocity from the anterior cervical triangle to the axilla was the same in motor and sensory fibres. The conduction velocity decreased 2m/s per 10 years increase of age. It was 70 m/s at 15-24 years and 58 m/s at 65-74 years. The velocity of the slowest components in sensory fibres was 17 m/s. Three selected case reports illustrate the diagnostic value of the method.     

Somatosensory evoked potentials,sensory nerve potentials and sensory nerve conduction in hereditary motor and sensory neuropathy type I

Summary Thirty-nine patients from six families with hereditary motor and sensory neuropathy type I and control subjects were included in this study. A neurological deficit score (NDS) was derived from a neurological examination and compared with neurophysiological test findings. Further, sensory nerve conduction velocities (SNCV) were compared with the motor nerve conduction velocities (MNCV). Five patients whom peaks of N11/N13 complex and N20 of the median nerve sensory evoked potential (SEP) could be recorded showed normal interpeak latency. The interpeak separation P14 N20 measured in six patients was normal. These findings point to the normal function of the central conductive pathways. Erb and cervical potentials of the median nerve SEP could be recorded in 10% and 12% of the patients, respectively. In contrast, about half of the patients showed a scalp N20, while in most of them no SNCV could be measured. In six patients far-field potential P14 of the median nerve SEP was the first detectable potential. Therefore, we argue in view of the anatomical structure of the thalamus, that the first generator for synchronizing and amplification of impulses is probably located in the thalamus. A third of the patients had a cortical sural nerve SEP, while no sural nerve potentials could be recorded. No association was found between the SEP findings and the NDS. There was an inverse correlation between median SNCV and the NDS, but no relationship between the former and sensory deficit alone. In 40% of the patients median SNCV and in 13% sural SNCV could be recorded and considered to be severely decreased. In contrast, the majority of the patients had mild to moderate sensory deficit. Furthermore, patients with measurable SNCVs had higher MNCVs and lower NDS than patients without measurable SNCVs.     

F-wave latency,the most sensitive nerve conduction parameter in patients with diabetes mellitus

In this study we examined the diagnostic sensitivity of minimal F-wave latency, F-wave persistence, motor nerve conduction velocity (MCV), and amplitude of the compound motor action potential (CMAP) of the median, ulnar, tibial, and peroneal nerves, and of sensory conduction velocity (SCV) and sensory nerve action potential (SNAP) amplitude of the sural nerve in 82 diabetic patients. For the median, ulnar, and tibial nerves the Z scores of the minimal F-wave latency were significantly larger than those of the MCV, and for all four motor nerves the Z scores of the minimal F-wave latency were significantly larger than those of the amplitude of the CMAP. The Z scores of the peroneal minimal F-wave latency exceeded those of peroneal MCV, sural SCV, and sural SNAP. F-wave persistence did not differ significantly from the reference values. In conclusion, minimal F-wave latency is the most sensitive measure for detection of nerve pathology and should be considered in electrophysiological studies of diabetic patients. © 1997 John Wiley & Sons, Inc. Muscle Nerve 20: 1296–1302, 1997     

Peripheral and central conduction abnormalities in diabetes mellitus

OBJECTIVES: To investigate peripheral and central somatosensory conduction in patients with diabetes. METHODS: The authors recorded sensory nerve action potentials and 5-channel somatosensory evoked potentials (SEPs) with noncephalic reference after median nerve stimulation in 55 patients with diabetes and 41 age- and height-matched normal subjects. The authors determined onset or peak latencies of the Erb's potential (N9) and the spinal N13-P13 and the cortical N20-P20 components, and obtained the central conduction time (CCT) by onset-to-onset and peak-to-peak measurements. RESULTS: Both onset and peak latencies of all SEP components were prolonged in patients with diabetes. The mean onset CCT in the diabetic group was 6.3 +/- 0.5 msec (mean +/- SD)-significantly longer than that in the control group (6.1 +/- 0.2 msec)-whereas no significant difference was found in the peak CCT. The amplitudes of N9 and N13-P13 components (but not N20-P20) were significantly smaller in the diabetic group. The peripheral sensory conduction velocity was also decreased in the diabetic group, but there was no significant correlation between peripheral conduction slowing and the onset of CCT prolongation. CONCLUSIONS: Diabetes affects conductive function in the central as well as peripheral somatosensory pathways. The CCT abnormality does not coincide with lowering of the peripheral sensory conduction. The current results do not favor a hypothesis that a central-peripheral distal axonopathy plays an important role in development of diabetic polyneuropathy.     

定量感觉及神经传导检测在糖尿病患者中的应用比较

目的:分析定量感觉检查(QST)及神经传导检测(NCS)在糖尿病患者中的应用价值.方法:用QST对100例2型糖尿病(T2DM)组和50例正常对照组分别进行四肢的冷觉(CS)、温觉(WS)、冷痛觉(CP)、热痛觉(HP)的感觉阈值测定并进行比较分析;并对T2DM患者进行上肢的正中神经、尺神经,下肢的胫神经、腓神经运动和感觉支的NCS、复合肌肉动作电位(CMAP)、感觉神经动作电位(SNAP)以及运动末梢潜伏期(DML)进行测定并分析.T2DM患者分为有症状组和无症状组,分别对QST及NCS的异常率进行分析并比较.结果:T2DM组QST和NCS结果与正常对照组比较差异有显著意义(P＜0.01); QST与NCS异常率比较差异有显著意义(P＜0.01),QST的异常率均显著大于NCS;提示糖尿病周围神经病(DPN)患者中周围神经小纤维受损比大纤维更明显,T2DM患者有症状组和无症状组各值比较差异均有显著意义(P＜0.01).结论:QST对DPN的早期诊断提供可靠依据,QST对DPN的诊断敏感性高,但特异性低,需与NCS结合对糖尿病周围神经状况进行评价更为完善.QST和NCS不能相互替代,全面了解DPN病情需QST和NCS结合,并密切结合临床.     

Delayed recovery of nerve conduction and vibratory sensibility after ischaemic block in patients with diabetes mellitus

OBJECTIVES—To determine if the recovery of nervefunction after ischaemic block is impaired in patients with diabetesmellitus relative to healthy controls.
METHODS—Median nerve impulse conduction andvibratory thresholds in the same innervation territory were studied inpatients with diabetes mellitus (n = 16) and age matched controls (n = 10) during and after 30 minutes of cuffing of the forearm.
RESULTS—Cuffing caused a 50% reduction of thecompound nerve action potential (CNAP) after 21.9 (SEM 1.6) minutes inpatients with diabetes mellitus and after 10.6 (0.7) minutes incontrols. After release of the cuff the half life for CNAP recovery was5.13 (0.45) minutes in patients with diabetes mellitus and <1 minutein controls. At seven minutes after release of the cuff CNAP was fullyrestored in the controls whereas in patients with diabetes mellitusCNAP had only reached 75.1 (4.1)% of its original amplitude. After onset of ischaemia it took 14.6 (1.9) minutes in patients with diabetesmellitus before the vibratory threshold was doubled, whereas this took5.8 (0.8) minutes in controls. After release of the cuff half time forrecovery of vibratory threshold was 8.8 (1.0) minutes in patients withdiabetes mellitus and 2.6 (0.3) minutes in controls. Ten minutes afterthe cuff was released the threshold was still raised (2.0 (0.3)-fold)in the diabetes mellitus group, whereas it was normalised in controls.Among patients with diabetes mellitus the impaired recovery correlatedwith older age, higher HbA1c, and signs of neuropathy, but not withblood glucose.
CONCLUSION—After ischaemia there is a delayedrecovery of nerve conduction and the vibratory sensibility in patientswith diabetes mellitus. Impaired recovery after ischaemic insults maycontribute to the high frequency of entrapment neuropathy in patientswith diabetes mellitus.

     

Motor and sensory conduction along the posterior interosseous nerve

The posterior interosseous nerve (PIN) is the main distal branch of the radial nerve. It innervates most of the extensor muscles of the forearm and contains deep sensory fibres directed to the ligaments and joints of the wrist. The presence of deep sensory fibres allow measurement of sensory conduction (SCV) other than motor nerve conduction velocity (MCV) along this nerve. Normal values of motor and sensory conduction along the terminal branches of the radial nerve distal to the elbow are reported. The results accord well with data previously reported.     

Symmetry of normal motor and sensory nerve conduction measurements

Nerve conduction measurements in normal subjects are assumed to be symmetric, but the normal limits of symmetry have not been determined. Full data on the limits of symmetry for commonly studied nerves are important in the clinical interpretation of nerve conduction data. We selected normal electrodiagnostic studies from archived electromyographic laboratory reports that included bilateral measurements of motor and sensory nerves. Symmetry of nerve conduction measures was confirmed, and only the median and ulnar sensory nerves had significant deviations from symmetry, supporting subclinical nerve damage in the most common dominant hand. The limits of symmetry were determined by calculating the 95th percentile for the differences between sides. For motor and sensory nerves, the range of 95th percentile limits was narrower for measures in upper extremity nerves compared to lower extremity nerves. Several reasons are offered for the wider limits of symmetry in lower extremity nerves. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21:498–503, 1998.     

Patterns of sensory nerve conduction abnormalities in demyelinating and axonal peripheral nerve disorders

The pattern of an abnormal median-normal sural (AMNS) sensory response is associated with acute and chronic inflammatory demyelinating polyradiculoneuropathy (AIDP and CIDP) and considered unusual in other types of neuropathy, although specificity and sensitivity of this pattern have not been evaluated. We compared sensory responses (patterns and absolute values) in patients with AIDP, CIDP, diabetic polyneuropathy (DP), and motor neuron disease (MND). Using strict criteria, the AMNS pattern occurred more frequently in recent onset AIDP (39%) compared with CIDP (28%), DP (14%–23%), or MND (22%) patients. This pattern was found in 3% of control subjects. The extreme pattern of an absent median-present sural response occurred only in AIDP and CIDP patients and in no other groups. Abnormalities of both nerves were more common in long-standing polyneuropathies such as CIDP and DP compared with AIDP or MND. Median nerve amplitudes were reduced significantly in AIDP, CIDP, and DP patients compared with MND patients, whereas sural nerve amplitudes were significantly reduced only in DP and CIDP patients. These findings may reflect early distal nerve involvement particularly in AIDP patients which is highlighted by differences in median and sural nerve recording electrode placement. We conclude that, in the appropriate clinical setting, the AMNS pattern, an absent median-present sural response pattern, or a reduced median amplitude compared with the sural amplitude supports a diagnosis of a primary demyelinating polyneuropathy. © 1993 John Wiley & Sons, Inc.     

Cutaneous sensory function in diabetes mellitus.

That disorders of cutaneous sensation are common in diabetes mellitus can be substantiated by quantitative cutaneous sensory testing. Cutaneous sensory disturbances are not clearly related to clinical factors such as the type, treatment, or duration of diabetes, or ocular complications. Diabetics can be distinguished from nondiabetics on quantitative examination of skin sensation. Juvenile diabetics appear to have fewer cutaneous abnormalities than adults who develop the disease, but the juvenile diabetic is not spared. Disorders of cutaneous sensation may represent a fundamental abnormality of the nervous system in diabetes mellitus. While altered peripheral sensory mechanisms are likely, abnormality of central sensory processing is not excluded by the results of this study.     

Ultrasound-guided needle positioning in sensory nerve conduction study of the sural nerve

ObjectivesTo evaluate the usefulness of ultrasound imaging to improve the positioning of the recording needle for nerve conduction studies (NCS) of the sural nerve.MethodsOrthodromic NCS of the sural nerve was performed in 44 consecutive patients evaluated for polyneuropathy. Ultrasound-guided needle positioning (USNP) was compared to conventional “blind” needle positioning (BNP), electrically guided needle positioning (EGNP), and to recordings with surface electrodes (SFN).ResultsThe mean distance between the needle tip and the nerve was 1.1 mm with USNP compared to 5.1 mm with BNP (p < 0.0001). The mean amplitude of the sensory nerve action potential (SNAP) was 21 μV with USNP and 11 μV with BNP (p < 0.0001). Compared to BNP, nerve–needle distances and SNAP amplitudes did not improve with EGNP. SNAP amplitudes recorded with SFN were significantly smaller than with BNP, EGNP and USNP.ConclusionUltrasound increases the precision of needle positioning markedly, compared to conventional methods. The amplitude of the recorded SNAP is usually clearly greater using USNP. In addition, USNP is faster, less painful and less dependent on the patient.SignificanceUSNP is superior to BNP, EGNP, and SFN in accurate measurement of SNAP amplitude. It has a potential use in the routine near-nerve needle sensory NCS of pure sensory nerves.     

Normal sensory conduction in the saphenous nerve in man.

Measurements of the sensory conduction velocity and the parameters of nerve action potentials in the saphenous nerve offer many advantages, compared with measurements in other nerves of the leg, regarding accuracy and the time required to complete the investigations. Therefore, the electroneurographical examination of the saphenous nerve is recommended in the early diagnosis of polyneuropathies and is indispensable in the exact diagnosis of proximal neuropathies and lesions of the femoral nerve. In the present study we indicate the proximal and distal segments of the saphenous nerve and illustrate the nerve action potentials from 70 normal subjects.     

Median mixed and sensory nerve conduction studies in carpal tunnel syndrome

Objective: To assess the sensitivities and specificities of velocity differences between median mixed nerve conduction across the wrist (Medmxpw) and (I) median mixed nerve conduction in the forearm (Medmxf) and (II) palm to D2 sensory conduction (MedpD2). Design and Methods: We prospectively studied 67 limbs of patients with clinically definite carpal tunnel syndrome (CTS). Medmxf and Medmxpw were performed by stimulating the median nerve at the elbow and palm respectively and recording at the proximal wrist crease. We also compared conventional median sensory (D2–wrist) and mixed (palm–wrist) tests in all patients. Thirty limbs of asymptomatic subjects served as normal controls and 21 limbs of subjects with other neuropathies served as diseased controls; control data was collected prospectively. Results: The sensitivity of the MedpD2–Medmxpw difference (0.87) was significantly greater than that of the Medmxf–Medmxpw difference (0.61, P<0.001). Both tests were similar and highly specific (0.98 and 0.96, respectively). Conclusions: The MedpD2–Medmxpw study is among the most sensitive and specific electrophysiologic tests for CTS.