Sensory Nerve Conduction Studies (sensory + nerve_conduction_studies)

Distribution by Scientific Domains


Selected Abstracts


Ulnar neuropathy at the elbow due to unusual sleep position

EUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2000
J. Finsterer
Abnormal strain of the ulnar nerve over the sulcus due to an unusual sleep position is a rare cause of ulnar neuropathy at the elbow. A 57-year-old patient with Mandelung's deformity developed progressive weakness in the flexion of fingers 4 and 5 and in finger straddling on the left side. Additionally, there was slight wasting of the left hypothenar and the left interossei muscles. Motor and sensory nerve conduction studies of the left ulnar nerve showed delayed conduction velocities over the left ulnar sulcus. He preferred to sleep in a left lateral position with his head lying on a headrest roll, his left forearm being flexed at 110° and his hand lying either under his cheek or placed on the roll. Only three weeks after the patient had been advised to change his sleep position and to sleep without the headrest roll, weakness markedly improved. This case shows that sleeping in a lateral position with the head on a headrest roll and the hand placed on the roll or under the cheek may cause ulnar neuropathy at the elbow. Change of such a habitual sleep position promptly resolves the symptoms. [source]


Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 81

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003
S Lori
Symptomatic neuropathy in young patients with type 1 Diabetes Mellitus (t1DM) is rare but subclinical peripheral alterations can be assessed by electroclinical evaluation. This study aimed to assess prevalence of clinical and subclinical peripheral neuropathy in patients with t1DM. Motor and/or sensory nerve conduction studies of both median, ulnar, peroneal, tibial and sural nerves and standard clinical examination of peripheral nervous system were performed in 83 patients (27 females and 56 males) with diabetes onset since five years. The mean age of patients was 19.89 (range 9,28.3) years, the mean disease duration was 9.61(range 4.4,19.3) and the mean age at the onset of diabetes was 9.02 (range 0.8,23.5). Five patients (6.02 %) had both symptomatic (light clinical abnormalities as paresthesias and mild reduction of vibratory sensibility) and electrophysiologic neuropathy and six (7.2 %) with mild abnormal nerve conduction studies were totally asymptomatic (subclinical neuropathy). The majority of symptoms and electrophysiological alterations were found on the lower limbs. Only two patients had a minimal distal neuropathy of median nerve. No patients showed laboratory evidence of early renal complications or systemic hypertension; 5 (6.02 %) had early diabetic retinal abnormalities as microaneurisms, seen by fundus examination. Analysis of sex, age of onset, duration of diabetes, age at the date of electrophysiologic examination, Hemoglobin A1c (mean level of the last two years), association with retinal abnormalities and clinical assessment was performed (Fisher Exact Test, ANOVA). No correlation was found with the age at the onset, retinal abnormalities and glycaemic control index. Peripheral neuropathy was significantly related with patient age at the date of electrophysiological study and duration of t1DM. [source]


Neuropathy Associated With Anti-Chondroitin Sulfate C IgM Antibodies

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2001
B Bossi
Chondroitin Sulfate C (ChS-C), is a glycosaminoglycan present in the membranes of neurons and axons. Anti-ChS-C IgM antibodies have been reported in patients with predominantly sensory neuropathy (PN) often associated with IgM monoclonal gammopathy, but also in some neurological controls. In order to evaluate the frequency and clinical correlate of anti-ChS-C IgM antibodies, we tested them by a new Covalink ELISA technique in sera from 206 patients with IgM monoclonal gammopathy including 79 with PN (PN+IgM) with unknown IgM reactivity, 65 with PN with antibodies to the myelin-associated glycoprotein and 62 without PN, and from 33 patients with PN of other causes, 30 with other neurological and non-neurological diseases and 23 normal subjects. We only found high titers of anti-ChS-C IgM in two patients (1/128,000 and 1/256,000 respectively) with IgM monoclonal gammopathy: one had Waldenström Macroglobulinemia diagnosed seven years before and a 3 year history of slowly progressive limb weakness, finger paresthesias, unsteady gait and occasional nocturnal cramps. Neurological examination revealed a predominantly large-fiber sensory neuropathy with mild distal atrophy and weakness in upper and lower limbs. Electrophysiological and morphological studies were suggestive of a predominantly demyelinating neuropathy. The other patient had IgM MGUS without PN at the time of antibody testing but developed finger paresthesias seven years later, when he had decreased position sense and abnormal sensory nerve conduction studies. In conclusion high titers of anti-ChS-C IgM, though infrequent, were always associated with the presence or development of sensory PN in patients with IgM M-protein, supporting a possible role for these antibodies in the neuropathy. [source]


A New Simple Neurophysiological Method (Through Conventional Electrical Stimulation) To Assess Function Of Tactile Receptors And Related Nerve Fibers

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2001
L Padua
Sometimes standard sensory nerve conduction studies show normal results in patients with definite symptoms of sensory polyneuropathy. This is usually explained because standard neurophysiological tests evaluate only large myelinated fibers and do not assess the slowest conducting fibers, more distal segments of the nerves and tactile receptors. Tactile stimulation is a test, not routinely available, that assesses the function of tactile receptors and conduction of fibers that are depolarized by these receptors. During conventional sensory nerve conduction studies (in patients and healthy subjects) through surface electrodes, where we slowly increased the intensity of the stimulus, we occasionally observed a sensory response characterized by a particular morphology with two peaks. After several experiments (performed in the neurophysiological laboratories of Catholic University of Rome and of University of Uppsala) we argued that the double component of the response is the expression of the stimulation of tactile receptors (and depolarization of their related fibers). Therefore an electrical stimulation through conventional EMG equipment allows us to assess function of tactile receptors (and related nerve fibers). This observation may have important diagnostic application in clinical practice to evaluate suspected polyneuropathies negative to neurophysiological conduction studies. [source]


Clinical utility of dorsal sural nerve conduction studies

MUSCLE AND NERVE, Issue 6 2001
James M. Killian MD
Abstract A technique of testing sensory nerve conduction of the dorsal sural nerve in the foot was used in 38 normal subjects and 70 patients with peripheral neuropathies. The normal dorsal sural sensory nerve action potential (SNAP) had a mean amplitude of 8.9 ,V (range 5,15 ,V), mean latency to negative peak of 4.0 ms (range 3.2,4.7 ms), and mean conduction velocity of 34.8 m/s (range 30,44 m/s). Optimal placement of the recording electrodes to obtain a maximal nerve action potential was proximal to digits 4 and 5. Cooling to below 25°C prolonged the latency but did not decrease the SNAP amplitude. Among the patients with peripheral neuropathy, dorsal sural SNAP was absent in 68 (97%), whereas only 54 (77%) showed abnormalities of sural sensory conduction. The diagnostic sensitivity of sensory nerve conduction studies in peripheral neuropathies may be significantly improved by the use of this technique for evaluating the action potential of the dorsal sural nerve. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 817,820, 2001 [source]