Electrodiagnosis

A theoretical investigation of different electroneurogram recording techniques using electrode cuffs is presented. A new screened tripole arrangement is proposed with a higher inherent signal to interference ratio than the true tripole, which also allows the nulling of the residual electromyogram signal. The reduction in interference is small because the electrode impedance is large compared to the source resistance.

Introduction: Dr. C. Miller Fisher described the appearance of unilateral facial palsy after resolution of ataxia in a patient with the eponymic Miller Fisher syndrome (MFS). However, there have been very few reports of delayed appearance of facial weakness in Guillain-Barré syndrome (GBS) and MFS when the other neurological signs reached nadir or started improving. Methods: In this study we reviewed the clinical and laboratory findings of consecutive patients with GBS (n = 195) and MFS (n = 68). Results: Delayed facial weakness occurred in 12 (6%) GBS and 4 (6%) MFS patients and was unilateral in 5 (42%) GBS and 2 (50%) MFS patients. In those patients with delayed facial weakness, neither limb weakness nor ataxia progressed, and facial weakness disappeared without immunotherapy. Conclusions: Because facial weakness can lead to further morbidity, it would be prudent for clinicians to warn patients of this possibility, although additional immunotherapy is usually not required. Muscle...

The study assessed HIV-related and anti-retroviral therapy-induced neuropathy in myelinated and unmyelinated nerve fibers. One hundred consecutive HIV patients were examined clinically and standard nerve conduction velocities were measured. In addition, electrically induced sympathetic skin response (SSR) was assessed in the palms and soles. The difference in delay of SSR in palms and soles (ΔSSR) was calculated as an indirect measure of C-fiber conduction velocity. Thick fiber conduction velocities significantly decreased with age and increasing stage of the disease, whereas no effect of stage was found for ΔSSR ( p = 0.6). In contrast, medication of at least one of the most known neurotoxic drugs zalcitabine, stavudine, or didanosine did not result in significantly lower conduction velocities in thick fibers (51.29 ± 3.4 m/s vs. 50.86 ± 3.5 m/s), but was related to an increased ΔSSR. ΔSSR allows an indirect measurement of C-fiber conduction velocity. In HIV this measure of unmyelinated sympathetic fibers was most sensitive to anti-viral treatment whereas conduction velocity of myelinated somatic fibers was more sensitive to disease-related neuropathy. The results suggest that HIV neuropathy preferably affects myelinated and anti-retroviral therapy unmyelinated fibers.

Electrical impedance spectroscopy is a minimally invasive technique that has clear advantages for living tissue characterisation owing to its low cost and ease of use. The present paper describes how this technique can be applied to breast tissue classification and breast cancer detection. Statistical analysis is used to derive a set of rules based on features extracted from the graphical representation of electrical impedance spectra. These rules are used hierarchically to discriminate several classes of breast tissue. Results of statistical classification obtained from a data set of 106 cases representing six classes of excised breast tissue show an overall classification efficiency of ~92% with carcinoma discrimination > 86%.

Objective: To estimate the potential diagnostic added value of the Awaji criteria for diagnosis of amyotrophic lateral sclerosis (ALS), which have been compared with the previously accepted gold standard the revised El Escorial criteria in several studies. Data Sources: MEDLINE and Web of Science (until October 2011). Study Selection: We searched for studies testing the diagnostic accuracy of the Awaji criteria vs the revised El Escorial criteria in patients referred with suspected ALS.

This paper deals with contact currents that may occur when the human body is in contact with two electrodes at different electrical potentials, e.g., an electrical/electronic device and the floor. Actually, any device must comply not only with electromagnetic compatibility and safety requirements, but also with specific electromagnetic field exposure recommendations in order to prevent health hazards for the occupational and general public population. Since the contact currents depend on the applied voltage and on the human body impedance, this last parameter has been measured for several configurations in a broadband frequency range, from 40 Hz to 110 MHz. From the measurement results, a new equivalent circuit of the human body impedance is derived by using a vector-fitting procedure. This equivalent circuit is very easy and can be adopted for compliance tests against contact currents. Index Terms-Bioelectric phenomena, contact currents, electromagnetic field (EMF) exposure, human body impedance, safety standards. I. INTRODUCTION T HE hazards to humans due to exposure to electromagnetic fields (EMF) have been well studied and documented [1], [2]. Proven or short-term adverse health effects refer mainly to the heating of the exposed regions at high-frequency radiations [3], [4], and to the circulation of induced currents inside regions exposed at low-frequency electric or magnetic fields [5], [6]. Another important effect of low-frequency exposures is represented by contact currents occurring when a person touches conductive surfaces at different potential and becomes a path for the current flow through the body [7]. Existing exposure standards, e.g., International Council on Nonionizing Radiation Protection (ICNIRP), IEEE C95.6-2002, and IEEE C95.1-2005 [8]-[10], present guidelines and rules to prevent the exposure of humans to EMFs. These safety standards provide recommendations or limits in terms of basic

Previous histochemical studies in the demyelinating form of Guillain-Barré syndrome (GBS), acute inflammatory demyelinating polyneuropathy (AIDP), have shown complement deposition on the surface of Schwann cells, and therefore unknown epitopes would be present on the outer surface of Schwann cells. We used a proteomic-based approach to search for the target molecules of AIDP in the extracted proteins from schwannoma cells. Sera were obtained from 40 patients with GBS, 31 controls with inflammatory disease, and 46 normal controls. We found that patients with AIDP after cytomegalovirus (CMV) infection have serum autoantibodies against membrane-organizing extension spike protein (moesin), which is expressed in the Schwann cell processes at the nodes of Ranvier and is crucial for myelination. Of the 40 patients with GBS, 6 had recent CMV infection and 5 of them (83%) had high levels of serum immunoglobulin G antibodies against moesin. The anti-moesin antibodies were found in none of the...

Introduction: The aim of this study was to compare the clinical accuracy, reliability, and repeatability of laser Doppler flowmetry (LDF), an electric pulp test (EPT), and various thermal pulp sensibility tests. Methods: Pulp tests were done on 121 teeth in 20 subjects by using LDF, EPT, and thermal pulp testing (CO 2 , Endo Frost [EF], Ice) during 2 or 3 test sessions with at least 1-week intervals. The order of testing was reversed on the second visit. A laser Doppler flowmeter was used to measure mean pulp blood flow (Flux) calibrated against a brownian motion medium and zeroed against a static reflector. The laser source was 780 nm, with 0.5-mm fiber separation in the probe, 3.1 kHz as the primary bandwidth for filter set to 0.1-second time output constant. Customized polyvinylsiloxane splints were fabricated for each participant, and a minimum of 90-second recording time was used for each tooth. Raw data were analyzed by using repeated measure analysis of variance, pairwise comparisons, and interclass correlations (ICC). Results: The accuracy of EPT, CO 2 , and LDF tests was 97.7%, 97.0%, and 96.3%, respectively, without significant differences (P > .3). Accuracy of EF and Ice was 90.7% and 84.8%, respectively. EPT (P = .015) and CO 2 (P = .022) were significantly more accurate than EF. LDF was more accurate than EF, but this was not statistically significant (P = .063). Ice was significantly less accurate than EPT (P = .004), CO 2 (P = .005), LDF (P = .006), and EF (P = .019). With the exception of Ice (effect of visit: F 2,38 = 5.67, mean squared error = 0.01, P = .007, h 2 p = 0.23), all tests were reliable. Ice (ICC = 0.677) and LDF (ICC = 0.654) were the most repeatable of the tests, whereas EPT (ICC = 0.434) and CO 2 (ICC = 0.432) were less repeatable. Conclusions: CO 2 , EPT, and LDF were reliable and the most accurate tests, but CO 2 and EPT were less repeatable yet less timeconsuming than LDF. EF was reliable but not as accurate as EPT and CO 2 and less repeatable than Ice and LDF. Ice was the most repeatable but the least accurate and least reliable test. (J Endod 2011;37:1619-1623

Nerve injury is one of the most serious complications associated with limb-lengthening. We examined the risk, assessment, and treatment of nerve lesions associated with limb-lengthening. We retrospectively studied the records on 814 limb-lengthening procedures. Nerve lesions were defined by clinical signs and symptoms of motor function impairment, sensory alterations, referred pain in the distribution of an affected nerve, and/or positive results of quantitative sensory testing with use of a pressure specified sensory device. Seventy-six (9.3%) of the limbs had a nerve lesion. Eighty-four percent of the nerve lesions occurred during gradual distraction, and 16% occurred immediately following surgery. The pressure specified sensory device showed 100% sensitivity and 86% specificity in the detection of nerve injuries. The patients in whom the lesion was diagnosed with this method, or with this method as well as with nerve conduction studies, had significantly faster recovery than did ...

Neurophysiological classification and sensitivity in 500 carpal tunnel syndrome hands. Acta Neurol Scand 1997: 96: 211-217. 0 Munksgaard 1997 Objectives -To evaluate the following points about carpal tunnel syndrome (CTS): 1) characterization of a wide population; 2) sensitivity of electrodiagnostic tests, and particularly the contribution of disto-proximal ratio test; 3) validity of a neurophysiological classification developed by us.

Background: Diabetes is the most important cause of peripheral neuropathy (DPN). No definitive treatment for DPN has been established, and very few data on the role of exercise training on DPN have been reported. Aim of the study: We sought to examine the effects of long-term exercise training on the development of DPN in both Types 1 and 2 diabetic patients. Participants and methods: Seventy-eight diabetic patients without signs and symptoms of peripheral DPN were enrolled, randomized, and subdivided in two groups: 31 diabetic participants [15 f, 16 m; 49F15.5 years old; body mass index (BMI)=27.9F4.7], who performed a prescribed and supervised 4 h/ week brisk walking on a treadmill at 50% to 85% of the heart rate reserve (exercise group: EXE), and a control group of 47 diabetic participants (CON; 24 f, 23 m; 52.9F13.4 years old; BMI=30.9F8.4). Vibration perception threshold (VPT), nerve distal latency (DL), nerve conduction velocity (NCV), and nerve action potential amplitude (NAPA) in the lower limbs were measured. Results: We found significant differences on # (delta) in NCV for both peroneal and sural motor nerve between the EXE and CON groups during the study period ( Pb.001, for both). The percentage of diabetic patients that developed motor neuropathy and sensory neuropathy during the 4 years of the study was significantly higher in the CON than the EXE group (17% vs. 0.0%, Pb.05, and 29.8% vs. 6.45%, Pb.05, respectively). In addition, the percentage of diabetic patients who developed increased VPT (25 V) during the study was significantly higher in the CON than the EXE group (21.3% vs. 12.9%, Pb.05). Change on Hallux VPT from baseline to the end of the study was significantly different between the EXE and CON groups ( Pb.05); no significant change in Malleolus VPT between the two groups occurred. Conclusions: This study suggests, for the first time, that long-term aerobic exercise training can prevent the onset or modify the natural history of DPN. D

The Semmes-Weinstein Monofilament Test (SWMT) is a clinical widely used test to quantify the sensibility in patients with Carpal Tunnel Syndrome (CTS). No study has investigated the relationship between the SWMT and sensory nerve conduction studies (SNCS) in patients with CTS. To assess the relationship between the SWMT and SNCS findings in patients with CTS. This cross-sectional clinical measurement study included 35 patients with CTS (55 hands) with a mean age of 45 ± 12 years. The outcome measures were the SWMT and SNCS measures of distal latency (DLs), amplitude (AMPs), and nerve conduction velocity (NCV). The median innervated fingers were tested using SWMT and electrodiagnostic tests. The primary outcome was the correlations between the SWMTs and NCS measures. All of the patients/hands had abnormal NCS findings. When looking at the three digits of interest (thumb, index and middle), the thumb SWMTs had the highest number of abnormal findings (58.2%), with the middle digit havi...

Electrical impedance spectroscopy is a minimally invasive technique that has clear advantages for living tissue characterisation owing to its low cost and ease of use. The present paper describes how this technique can be applied to breast tissue classification and breast cancer detection. Statistical analysis is used to derive a set of rules based on features extracted from the graphical representation of electrical impedance spectra. These rules are used hierarchically to discriminate several classes of breast tissue. Results of statistical classification obtained from a data set of 106 cases representing six classes of excised breast tissue show an overall classification efficiency of ~92% with carcinoma discrimination > 86%.

In order to explore the suitability of adding female voices to the tenor sections of amateur choirs, six male and six female tenors were screened for voice characteristics. Audio signals and signals from an electroglottograph were analyzed by means of VoceVista computer software. All subjects produced closed quotients of 60% or higher in singing with a loud chest voice. There was more variance between the individuals than between groups of male and female singers. Long-time average spectra showed a general trend in the presence of a high-intensity peak between 4 and 5 kHz. The results revealed no signifi cant differences in the most important voice characteristics between female and male tenor voices.

Carpal tunnel syndrome (CTS) is a constellation of symptoms associated with compression of the median nerve at the wrist. The pathophysiology of CTS is not fully understood but mechanical aspects of injury within the carpal tunnel are most likely. The issues of ischemia, mechanical trauma, ectopic impulse generation, demyelination, tendonitis, elevated carpal tunnel pressure, mechanical factors, small and large fiber involvement and the variability of symptoms are presented.

The change of fundamental voice frequency in continuous speech in female puberty was analysed in 47 girls by comparison of 2000 consecutive electroglottographic cycles in a reading situation. The results were compared with serum concentrations of androgens (dihydroepiandrosterone, delta-4-androstenedione, testosterone, and sex hormone binding globulin), oestrogens (oestradiol, oestrone, and oestronesulphate), and somatic puberty (weight, height, mamma stages, and pubic hair stages). Fundamental frequency in continuous speech was related only to oestrone r = -0.34, (P less than 0.05). But the tone range in continuous speech and the lowest tone in the phonetogram were found to be significantly correlated with many of the pubertal and hormone parameters. All these correlations could be explained by a common age-dependency. By multiple regression analysis different sets of variables for prediction of speaking fundamental frequency were found before and after menarche.

Objective: To develop a scientifically sound and clinically relevant evidence-based guideline for the treatment of painful diabetic neuropathy (PDN). Methods: We performed a systematic review of the literature from 1960 to August 2008 and classified the studies according to the American Academy of Neurology classification of evidence scheme for a therapeutic article, and recommendations were linked to the strength of the evidence. The basic question asked was: "What is the efficacy of a given treatment (pharmacological: anticonvulsants, antidepressants, opioids, others; and non-pharmacological: electrical stimulation, magnetic field treatment, low-intensity laser treatment, Reiki massage, others) to reduce pain and improve physical function and quality of life (QOL) in patients with PDN?" Results and Recommendations: Pregabalin is established as effective and should be offered for relief of PDN (Level A). Venlafaxine, duloxetine, amitriptyline, gabapentin, valproate, opioids (morphine sulphate, tramadol, and oxycodone controlled-release), and capsaicin are probably effective and should be considered for treatment of PDN (Level B). Other treatments have less robust evidence or the evidence is negative. Effective treatments for PDN are available, but many have side effects that limit their usefulness, and few studies have sufficient information on treatment effects on function and QOL. PM R 2011;3:345-352 Diabetic sensorimotor polyneuropathy represents a diffuse symmetrical and length-dependent injury to peripheral nerves that has major implications on quality of life (QOL), morbidity, and costs from a public health perspective [1,2]. Painful diabetic neuropathy (PDN) affects 16% of patients with diabetes, and it is frequently unreported (12.5%) and more frequently untreated (39%) . PDN presents an ongoing management problem for patients, caregivers, and physicians. There are many treatment options available, and a rational approach to treating the patient with PDN requires an understanding of the evidence for each intervention. This guideline addresses the efficacy of pharmacological and nonpharmacological treatments to reduce pain and improve physical function and QOL in patients with PDN. The pharmacological agents reviewed include anticonvulsants, antidepressants, opioids, antiarrhythmics, cannabinoids, aldose reductase inhibitors, protein kinase C beta inhibitors, antioxidants (alpha lipoic acid), transketolase activators (thiamines and allithiamines), topical medications (analgesic patches, anesthetic patches, capsaicin cream, clonidine), and others. The nonpharmacological modalities include infrared therapy, shoe magnets, exercise, acupuncture, external stimulation (TENS), spinal cord stimulation, biofeedback and behavioral therapy, surgical decompression, and intrathecal baclofen.

Different ways of expressing the severity of carpal tunnel syndrome (CTS) are found in the existing literature and in clinical records. This paper documents the distribution of patients on a scale based upon the nerve conduction study findings, which are largely independent of the exact normal values used in any given laboratory and demonstrate a highly significant linear relationship between the neurophysiological grading and a numerical score derived from the clinical history. Patients with more characteristic stories of CTS generally have higher neurophysiological grades. The scale is as follows: normal (grade 0); very mild (grade 1), CTS demonstrable only with most sensitive tests; mild (grade 2), sensory nerve conduction velocity slow on finger/wrist measurement, normal terminal motor latency; moderate (grade 3), sensory potential preserved with motor slowing, distal motor latency to abductor pollicis brevis (APB) < 6.5 ms; severe (grade 4), sensory potentials absent but motor response preserved, distal motor latency to APB < 6.5 ms; very severe (grade 5), terminal latency to APB > 6.5 ms; extremely severe (grade 6), sensory and motor potentials effectively unrecordable (surface motor potential from APB < 0.2 mV amplitude).

Peripheral neuropathy, mononeuropathy and polyneuropathy, are not common in pregnancy. When complaints occur, however, even if minor, they can be bothersome to the pregnant woman. Peripheral nerve function may threaten the mother and fetus in various ways during gestation. Quick recognition and treatment efforts should therefore be the clinician&amp;#39;s goal. This article reviews peripheral neuropathy in pregnancy.

G enerally, physiological modeling and biomedical signal processing constitute two important paradigms of biomedical engineering (BME): their fundamental concepts are taught starting from undergraduate studies and are more completely dealt with in the last years of graduate curricula, as well as in Ph.D. courses. Traditionally, these two cultural aspects were separated, with the first one more oriented to physiological issues and how to model them and the second one more dedicated to the development of processing tools or algorithms to enhance useful information from clinical data. A practical consequence was that those who did models did not do

Carpal tunnel syndrome (CTS) is the most common nerve entrapment. Electrodiagnostic (EDX) studies are a valid and reliable means of confirming the diagnosis. This monograph addresses the various EDX techniques used to evaluate the median nerve at the wrist. It also demonstrates the limitations of EDX studies with a focus on the sensitivity and specificity of EDX testing for CTS. The need to use reference values for populations such as diabetics and active workers, where normative values differ from conventional cutoffs used to confirm suspected CTS, is presented. The value of needle electromyography (EMG) is examined. 44: 597-607, 2011 Carpal tunnel syndrome (CTS) is a clinical syn-Abbreviations: AANEM, American Association of Neuromuscular and Electrodiagnostic Medicine; AAOS, American Academy of Orthopedic Surgeons; APB, abductor pollicis brevis; CMAP, compound muscle action potential; CSI, combined summary index; CTS, carpal tunnel syndrome; EDX, electrodiagnostic; EMG, electromyography; inching, median sensory short segment stimulation across the wrist; MGA, Martin-Gruber anastomosis; MMW, median mononeuropathy at the wrist; NAP, nerve action potential; NCS, nerve conduction studies; palmdiff, median-ulnar mixed nerve palm latency difference from palm to wrist; ringdiff, median-ulnar sensory latency difference to the ring finger; SNAP, sensory nerve action potential; thumbdiff, median-radial latency difference to the thumb

M.N. is a 35-year-old otherwise healthy female software engineer with a 2-year history of intermittent right hand numbness that has worsened in the past 2-3 months. She endorses numbness in the hand, worse in the thumb, index, and middle fingers. Typing and driving aggravate her symptoms, and she frequently wakes up at night with numbness in the hand. She also endorses intermittent neck pain that she believes is unrelated and occasional numbness in the forearm. She denies any weakness or history of dropping items.

Purpose With the frequent use of magnetic resonance imaging (MRI), patients with subtle and diffuse symptoms due to small syrinx cavities increasingly present to neurosurgical care. In this respect, a dilated central canal, hydromyelia, must be separated from patients with true syringomyelia with an underlying disorder, as they do not share clinical and radiological features. We hypothesize that a differentiation of these two entities with distinct diagnostic tools is possible. Methods To describe the entity of hydromyelia, we excluded all patients from the syringomyelia database (n = 142) with any obvious cause of a syringomyelia, any objective neurological deficits on clinical examination, pathological results on electrophysiological monitoring (SSEP, MEP, silent periods) or a widening of the spinal cord cavity of more than 6 mm on MRI [routine acquisitions with FLAIR, T1/T2-weighted images, Cine and CISS (constructive interference in steady-state) studies]. Life quality was assessed through SF-36 questionnaires and an individualized questionnaire for the clinical history, pain and alternative therapies. Results Forty patients (15 males/25 females) matched the criteria of a hydromyelia. With a mean age of 36.7 years (range 11–62), they almost all presented with pain (79%) or dysaesthesia of the limbs, with some having been an incidental finding (10%). Over a follow-up time of 36.9 months (range 6–93) there was no neurological or radiological deterioration. Conclusions Patients with a hydromyelia do not share clinical or radiological characteristics with patients harbouring a true syringomyelia. As hydromyelia does not represent a disease with an underlying pathology, no clinical or radiological progression has been seen. With sophisticated diagnostic tools to rule out any pathology this subset of patients can be identified.

Normal bladder function depends on the complex interaction of sensory and motor pathways. Bladder dysfunction can develop as a result of several neurological conditions. It can happen in a number of ways, including diabetic cystopathy, detrusor overactivity, bladder outlet obstruction, and urge and stress urinary incontinence. Diabetic neuropathy is the most common cause of peripheral neuropathy-associated bladder dysfunction. Guillain-Barré syndrome (GBS), human immunodeficiency virus (HIV)-associated neuropathy, chronic inflammatory demyelinating polyneuropathy (CIDP), and amyloid neuropathy are other major causes. The diagnosis of bladder dysfunction should be established by the history of neurological symptoms, neurological examination, and urological evaluation. Functional evaluation of the lower urinary tract includes cystometry, sphincter electromyography, uroflowmetry, and urethral pressure profilometry. Management of urinary symptoms in patients with bladder dysfunction is usually supportive. In some cases, alpha-blocker and/or anti-muscarinic agents are needed to help improve urinary dysfunction. Intermittent self-catheterization is needed occasionally for patients with slow and/or poor recovery.

A Bernese mountain dog was diagnosed with complex partial seizures that were supported by electroencephalographic findings. Clinical signs of the problem included ''star gazing," fly snapping, licking, vacuous chewing, and ongoing anxiety. Treatment with Huperzine A, a compound isolated from Chinese club moss with NMDA receptor blocking activity, anticholinesterase activity, and anticonvulsant properties, produced useful suppression of the abnormal behavior for more than months. A relapse occurred when the dog was treated with tramadol for joint pain and the improvement that had been made was not recaptured with Huperzine A. At this stage, phenobarbital therapy was instituted and the dog improved greatly. The role of Huperzine A in controlling seizures is discussed.

Electrodermal activity (EDA) at acupuncture points (acupoints) has been investigated for its utility as a diagnostic aid, a therapeutic monitoring tool, and a physiological outcome measure. The research methodologies reported in published trials, however, vary considerably and publications often lack sufficient details about electrical instrumentation, technical procedures, laboratory conditions, recorded measures, and control comparisons to permit a critical appraisal of the studies or to replicate promising findings. We developed a 10-category (54 subitems) Quality of Reporting scale based on technical issues associated with EDA measurements, publication requirements for reporting EDA in the psychophysiological literature, and recommendations from the CONSORT Statement for reporting clinical trials. Using our Quality of Reporting scale, we extracted data from 29 studies that evaluated EDA at acupoints in patients and generated weighted scores for each of the 10 categories of essential information. Only 9 of the 29 studies reviewed scored a mean of greater than 50% for reporting details of essential information. To rigorously build a program of research on EDA at acupoints we need to standardize research methodology and reporting protocols. We propose a checklist of recommended informational items to report in future clinical trials that record EDA at acupoints.

Acute motor axonal neuropathy (AMAN) is a pure motor axonal subtype of Guillain-Barré syndrome (GBS) that was identifi ed in the late 1990s. In Asia and Central and South America, it is the major subtype of GBS, seen in 30-65% of patients. AMAN progresses more rapidly and has an earlier peak than demyelinating GBS; tendon refl exes are relatively preserved or even exaggerated, and autonomic dysfunction is rare. One of the main causes is molecular mimicry of human gangliosides by Campylobacter jejuni lipo-oligosaccharides. In addition to axonal degeneration, electrophysiology shows rapidly reversible nerve conduction blockade or slowing, presumably due to pathological changes at the nodes or paranodes. Autoantibodies that bind to GM1 or GD1a gangliosides at the nodes of Ranvier activate complement and disrupt sodium-channel clusters and axoglial junctions, which leads to nerve conduction failure and muscle weakness. Improved understanding of the disease mechanism and pathophysiology might lead to new treatment options and improve the outlook for patients with AMAN.

The main goal of the thesis is to show the de-noising algorithms based upon the discrete wavelet transform (DWT) that can be applied successfully to enhance noisy multidimensional magnetic resonance (MR) data sets i.e two-dimensional (2-D) image slices and three-dimensional (3-D) image volumes. Noise removal or de-noising is an important task in image processing used to recover a signal that has been corrupted by noise. Random noise that is present in MR images is generated by electronic components in the instrumentation. The thesis present both 2-D image decomposition, thresholding and reconstruction and the 3-D de-noising of MR image volumes using the DWT as a new approach which can be used in the processing of biomedical images. A novel use of the complex wavelet transform for the study and application in the de-noising of MR images is presented in the main part of the thesis. Segmentation of image textures using a watershed transform and a wavelet based feature extraction for classification of image textures by a competitive neural network will be shown.

The sensitivity and specificity of nerve conduction studies (NCS'sJ and electromyography (EMG) for the diagnosis of carpal tunnel syndrome CTS) were evaluated by a critical review of the literature. With a search of the medical literature in English through May 1991, 165 articles were identified and reviewed on the basis of six criteria of scientific methodology. The findings of 11 articles that met all six criteria and the results of 48 additional studies that met four or five criteria are presented. We concluded that median sensory and motor NCS's are valid and reproducible clinical laboratory studies that confirm a clinical diagnosis of CTS with a high degree of sensitivity and specificity. Clinical practice recommendations are made based on a comparison of the sensitivities of the several different median nerve conduction study (NCS) techniques.

Tourniquet paralysis is an uncommon complication of surgery, and self-inflicted tourniquet paralysis has never been documented to our knowledge. We report a patient with bilateral self-induced tourniquet paralysis of the lower extremities, whose symptoms were initially attributed to an acute demyelinating sensorimotor polyneuropathy based on clinical presentation and electrodiagnostic study. After investigations failed to reveal a cause, he was found to have placed tourniquets on his legs because of a rare obsession with limb amputation known as apotemnophilia. Significant spontaneous partial resolution of clinical symptoms was noted after 6 weeks. Electrophysiologic evidence of segmental demyelination of multiple motor nerves localized to the same region may help to distinguish this condition from other forms of acute demyelinating polyneuropathy.

The sensitivity and specificity of nerve conduction studies (NCS'sJ and electromyography (EMG) for the diagnosis of carpal tunnel syndrome CTS) were evaluated by a critical review of the literature. With a search of the medical literature in English through May 1991, 165 articles were identified and reviewed on the basis of six criteria of scientific methodology. The findings of 11 articles that met all six criteria and the results of 48 additional studies that met four or five criteria are presented. We concluded that median sensory and motor NCS's are valid and reproducible clinical laboratory studies that confirm a clinical diagnosis of CTS with a high degree of sensitivity and specificity. Clinical practice recommendations are made based on a comparison of the sensitivities of the several different median nerve conduction study (NCS) techniques.

This article reviews the use of electrodiagnostic testing in disorders of neuromuscular transmission and discusses the differences between various presynaptic and postsynaptic disorders. Attention is paid to quality control issues that influence the sensitivity of repetitive nerve stimulation and single fiber electromyography. Electrodiagnostic testing, when used as an extension of the clinician&#39;s history and physical examination, will provide appropriate direction in establishing the diagnosis.