The purpose of this study was to document the ultrasonographic measurement differences in median nerve size between patients with carpal tunnel syndrome (CTS) and controls, and to correlate these findings with electrophysiological stage and motor unit number estimation (MUNE), thereby allowing us to test the validity of ultrasound as a diagnostic modality for assessing the severity of CTS. High-resolution sonography and electrophysiological studies were performed on 41 wrists of 27 patients and compared with findings on 40 wrists of 20 healthy individuals. On ultrasonographic views, cross-sectional area and flattening ratio in proximal, middle, and distal tunnel segments of the median nerve were measured both by calculating ellipsoid area by large and small cross-sectional diameters and by automated ellipsoid area calculation. We compared electrophysiological stage and MUNE with proximal, middle, and distal cross-sectional area and other ultrasonographic findings. All correlations between electrophysiological stage and cross-sectional areas in these different segments of the median nerve were significant with both measurement methods. Negative correlations were seen between MUNE and cross-sectional area in the proximal and middle segments, whereas no significant correlation was detected in the distal segment. Our results indicate that there are close correlations between the ultrasonographic findings and electrophysiological stage. Ultrasound also reflects the reduction in the number of axons estimated by the MUNE method. Therefore, we suggest that the ultrasonographic findings reflect the severity of disease in patients with CTS.

The aim of this study was to determine the effects of haemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) on P300 cognitive potentials in patients with chronic renal failure (CRF) and to find out if P300 potential is a valuable marker for following subclinical cognitive disorder.This study was performed in 42 patients with chronic uraemia, of whom 25 were on HD and 17 on CAPD, and in 25 healthy subjects. All the subjects were investigated in terms of P300 cognitive potential obtained from auditory stimuli with the oddball paradigm and the Mini-Mental State (MMS) examination. Patients undergoing HD were evaluated before (pre-dialysis) and after (post-dialysis) standard HD treatment. P300 latency was longer in HD patients than in the control group and CAPD patients. The MMS score was greater and P300 latency was shorter after a standard HD session when compared to pre-dialysis values in HD patients (p < 0.001 for both values). There was a negative correlation between P300 latency and MMS scores, and a positive correlation between P300 amplitude and MMS scores.In conclusion, P300 is useful for evaluating cognitive function in uraemia, even in asymptomatic patients, and CAPD is superior to HD in the management of cognitive impairment.

No abstract

The aim of this study was to determine the sensitivity of sympathetic skin response (SSR) in evaluating autonomic involvement in carpal tunnel syndrome (CTS) while simultaneously showing the axonal loss by motor unit number estimation (MUNE). Bilateral SSR were recorded by suprasternal stimulus in 50 hands of 31 patients and compared with 50 hands of 25 healthy volunteers. The groups were examined for sympathetic symptoms and sympathetic symptom scores (SSS) were determined. Axon count was performed on the abductor pollicis brevis (APB) muscle by using the MUNE method (with incremental technique) in both groups. There was no SSR difference between groups, although a significant difference was found for SSS. No relationships were found between SSR parameters and SSS or the electrophysiologic stage. MUNE of the APB muscle was significantly lower in CTS group and there was a negative correlation between MUNE and the electrophysiologic stage. The comparison of the MUNE and the amplitude of median compound muscle action potential indicated that MUNE is a highly sensitive method of determining severity in patients with CTS. In evaluating autonomic involvement in CTS, SSR does not seem to be a sensitive method. MUNE is a good indicator of motor reserve and can be helpful when following the treatment and prognosis of CTS in clinical practice.

Background and PurposeElectrodiagnostic studies can be used to confirm the diagnosis of lumbosacral radiculopathies, but more sensitive diagnostic methods are often needed to measure the ensuing motor neuronal loss and sympathetic failure.MethodsTwenty-six patients with lumbar radiculopathy and 30 controls were investigated using nerve conduction studies, motor unit number estimation (MUNE), testing of the sympathetic skin response (SSR), quantitative electromyography (QEMG), and magnetic resonance myelography (MRM).ResultsUsing QEMG as the gold standard, the sensitivity and specificity of MUNE for the abductor hallucis longus muscle were 71.4% and 70%, respectively. While they were 75% and 68.8%, respectively, when used MRM as gold standard. The sensitivity and specificity of MUNE for the extensor digitorum brevis muscle were 100% and 84.1%, respectively, when the peroneal motor amplitude as the gold standard. The SSR latency was slightly longer in the patients than in the controls.ConclusionsMUNE is a simple and sensitive test for evaluating autonomic function and for diagnosing lumbosacral radiculopathy in patients. MUNE could be used routinely as a guide for the rehabilitation of patients with radiculopathies. SSR measurements may reveal subtle sympathetic abnormalities in patients with lumbosacral radiculopathy.