Conduction in ulnar nerve bundles that innervate the proximal and distal muscles: a clinical trial

<p>Abstract</p> <p>Background</p> <p>This study aims to investigate and compare the conduction parameters of nerve bundles in the ulnar nerve that innervates the forearm muscles and hand muscles; routine electromyography study merely evaluates the nerve segment of distal (hand) muscles.</p> <p>Methods</p> <p>An electrophysiological evaluation, consisting of velocities, amplitudes, and durations of ulnar nerve bundles to 2 forearm muscles and the hypothenar muscles was performed on the same humeral segment.</p> <p>Results</p> <p>The velocities and durations of the compound muscle action potential (CMAP) of the ulnar nerve bundle to the proximal muscles were greater than to distal muscles, but the amplitudes were smaller.</p> <p>Conclusions</p> <p>Bundles in the ulnar nerve of proximal muscles have larger neuronal bodies and thicker nerve fibers than those in the same nerve in distal muscles, and their conduction velocities are higher. The CMAPs of proximal muscles also have smaller amplitudes and greater durations. These findings can be attributed to the desynchronization that is caused by a wider range of distribution in nerve fiber diameters.</p> <p>Conduction parameters of nerve fibers with different diameters in the same peripheral nerve can be estimated.</p

Reliability and validity of the Cornell Scale for Depression in Dementia in an elderly Turkish population.

OBJECTIVE: The reliability and validity of the Cornell Scale for Depression in Dementia were investigated in a Turkish population over 60 years of age. METHOD: Forty-six male and 34 female demented elderly people classified as demented according to DSM-IV criteria were included in the study. The Structured Clinical Interview for DSM-IV Clinical Version (SCID-I) was completed for all subjects to establish the diagnosis of major depression. The Cornell Scale for Depression in Dementia (CSDD), Geriatric Depression Scale (GDS), Mini Mental State Examination (MMSE) and Global Deterioration Scale (GDS) were used. RESULTS: A high test-retest correlation level (r: 0.93) was obtained for the total scores of the scale. The scale also showed high internal consistency (a: 0.86). The validity analysis of the scale resulted in a significant difference (p<0.001) between the total scores of the group with dementia and depression and the group with dementia but without depression. Two items (9-19) showed a low correlation (r<.30) in the test-retest analysis. On the other hand, two items (6-19) had a low item-total score correlation (r<.30). CONCLUSIONS: The results indicated that the scale is reliable and valid for diagnosing depression in dementia in an elderly Turkish population. We expect that the Cornell Scale for Depression in Dementia will be a useful instrument in pharmacological investigations and in studies of the phenomenology and course of depressive symptoms in demented patients

Findings of somatosensory evoked potential to stimulation of the sciatic nerve in two different rat strains.

No comparative study about somatosensory evoked potentials (SEP) on different rat strains has been done yet. It is evident that comparative SEP studies are important since different rat strains have different physiological properties. We aimed to compare early latency SEP values from stimulation of sciatic nerve in Wistar (Wr) and Sprague-Dawley (SDr) rats which are frequently used rat strains in experimental studies. In Wr group, the mean of first far field potential (Ff1) latency was shorter and the mean Ff1 amplitude was lower than that of Sprague-Dawley rat group. Mean cortical potential latency in Wr group was longer than that of SDr group while amplitude was not different. Central conduction time (CCT) in Wistar rat group was found to be longer than that of SDr group. Shorter Ff1 latency in Wr group implies that afferent volley reaches cervical posterior fasciculus from sciatic nerve earlier than SDr group while longer CP latency implies that afferent volley reaches cortex later than SDr group. Similarity between the latencies of lumbar potentials implies that peripheral conduction velocity has no effect on the difference of Ff1 latencies

The complementary role of different neurophysiological methods to demonstrate organicity in male with premature ejaculation and erectile dysfunction.

Erectile dysfunction and premature ejaculation are the most common male sexual disorders. Generally, it is considered that erectile dysfunction is related to organic factors whilst premature ejaculation is related to psychological factors. A detailed history along with physical examination such as using penile doppler, penile tumesans and ultrasonography are insufficient for differential diagnosis in 15-20% of cases. Therefore the role of neurophysiological techniques are important. In this study urological and biochemical investigations were used in conjunction with other neurophysiological methods. According to our results, using a neurophysiological test study on its own was ineffective. As a conclusion our study has shown that neurophysiological methods are important differential diagnosis of revealing suspicious organicity--generally believed to be due to psychological factors- in male sexual disorders

Nerve conduction parameters during ischemia-reperfusion in the rat sciatic nerve.

We investigated the duration of electrophysiological alterations in the rat sciatic nerves during ischemia-reperfusion. Motor nerve conduction velocities were lower than the control group in 1- and 2-hour ischaemia groups after one day while there was no reading for the 3-hour ischaemia group till the seventh day, which was lower than control group. In the 1-hour ischaemia group, all parameters returned to normal on the seventh day but motor nerve conduction velocity decreased again on the 14th day and then returned to a normal level once again on the 21st day. All parameters were found to return to normal levels in the 2-hour ischaemia group on the 30th day and the 3-hour ischaemia group on the 60th day

Nasopharyngeal carcinoma presenting with horner syndrome and carotid-sinus syncope.

INTRODUCTION: Nasopharyngeal carcinoma can present with different neurological signs and findings. In this paper, we report a patient presenting with Horner syndrome and syncopal episodes who was finally diagnosed with nasopharyngeal carcinoma. CASE REPORT: A 56-year-old man presented with a history of slowly progressive right upper-eyelid droop for the last 1.5 months and episodes of loss of consciousness. After detailed clinical and laboratory examinations, the patient had the final diagnosis of metastatic nasopharyngeal carcinoma. CONCLUSIONS: This is the first case with nasopharyngeal carcinoma presenting with both Horner syndrome and carotid-sinus syncope. The mechanism of Horner syndrome and the syncopal episodes and their relation with the lesion location are discussed

Effect of hyperglycemia on conduction parameters of tibial nerve's fibers to different muscles: A rat model.

INTRODUCTION: Routine conduction studies reflect the summation of all nerve fibers in a peripheral nerve. Nerve fiber groups to distal, small muscles have smaller diameters than the ones to large proximal muscles. There may be minimal differences between the diameters of nerve fiber groups innervating different muscles; even they are all same type of fibers. So, in neuropathic processes some nerve fiber groups may be more seriously affected. MATERIALS AND METHODS: 14 rats ( 7 diabetic, 7 control) were studied. Tibial nerve was stimulated from two points and while recorded from a distal (foot intrinsic muscles) and a proximal (gastrocnemius) muscle. RESULTS: There was a significant difference between the proximal and distal recorded conduction velocities. Both proximal and distal recorded conduction velocities decreased during the hyperglycemic process. DISCUSSION: Our method successfully demonstrated different nerve fiber groups; but, the neuropathic process seemed to be homogeneous in both fiber groups

Comparison of conduction velocities of nerve fibers to smaller and larger muscles in rats.

The aim of this study was to compare conduction velocities of motor fibers to smaller and larger muscles and to investigate the advantages and disadvantages of recordings from the gastrocnemius muscle with surface electrodes over the recordings from small foot muscles (interosseous muscles) with needle electrodes in rats. Surface and needle recordings are suitable in measuring the motor conduction velocity of the sciatic (tibial) nerve. It should be noted that the motor velocity measured from the gastrocnemius muscle is higher than the motor velocity elicited from small foot muscles. Surface recordings provide information on the amplitude and duration of M responses

Wallenberg Syndrome following neck cracking: a case report.

Cracking the neck is an age-old practice in contravention of its dangerous affects. One of these affects is Brain stem strokes and in this report we describe a patient with Wallenberg syndrome due to neck cracking who is the one of the rare cases in the literature