Needle electromyographic findings in 98 patients with myositis

BACKGROUND/AIMS: Little is known about the distribution of electromyographic (EMG) abnormalities in myositis even though this is relevant in daily practice. METHODS: A retrospective semiquantitative analysis of needle EMG findings was performed in a group of 98 patients with myositis. The frequency, type, and distribution of abnormalities were studied. The influence of the use of corticosteroids and the stage of the disease were evaluated. RESULTS: In most patients, a myopathic pattern with spontaneous activity was found, although several clinically relevant exceptions were noted. Long-duration motor unit potentials were found in all three diagnostic groups and were not associated with disease duration. In the lower extremity a distal to proximal gradient was present, adding to the diagnostic confusion with neurogenic diseases, and spontaneous activity was absent in a relatively large group although none of the patients in the acute stage of the disease had a normal EMG. The use of corticosteroids reduced the number of abnormal findings in dermatomyositis and polymyositis, but not in inclusion body myositis. CONCLUSION: A myopathic pattern with spontaneous activity was most frequently found, although several clinically relevant exceptions were noted. These results illustrate the spectrum of EMG findings in myositis, and may aid the clinician in the interpretation of the EMG in these patients.     

Variation in diagnostic strategy of the EMG examination--a multicentre study.

OBJECTIVES: In order to improve the universal quality of the EMG examination, knowledge about the variation among physicians is needed. METHODS: The variation among physicians in diagnostic strategy or criteria for diagnosing was analysed from a multicentre database with 940 EMG examinations sampled by seven physicians from six laboratories in Europe. RESULTS: For the whole group of patients as well as for the subgroup of patients with polyneuropathy, variation among physicians in examination techniques, number of examined structures per patient and number of abnormal structures per patient required for a diagnosis was found. Some of the variation may be explained by use of different techniques, which showed differences in sensitivity, while some of the variation may be due to differences in diagnostic strategy and criteria for diagnosing. CONCLUSIONS: The study indicates a need for development and revision of international guidelines for EMG practice although implementation of standards requires caution.     

The Edinburgh Principles with accompanying guidelines and recommendations

A panel of experts attending a 3‐day meeting held in Edinburgh, UK, in February 2001 was charged with producing a set of principles outlining the rights and needs of people with intellectual disability (ID) and dementia, and defining service practices which would enhance the supports available to them. The Edinburgh Principles, seven statements identifying a foundation for the design and support of services to people with ID affected by dementia, and their carers, were the outcome of this meeting. The accompanying guidelines and recommendations document provides an elaboration of the key points associated with the Principles and is structured toward a four‐point approach: (1) adopting a workable philosophy of care; (2) adapting practices at the point of service delivery; (3) working out the coordination of diverse systems; and (4) promoting relevant research. It is expected that the Principles will be adopted by service organizations world‐wide, and that the accompanying document will provide a useful and detailed baseline from which further discussions, research efforts and practice development can progress.     

Resource document on the use of restraint and seclusion in correctional mental health care

This resource document discusses the use of seclusion or restraint for purposes of mental health intervention in correctional facilities. Correctional mental health standards essentially state that seclusion or restraint, when used for health care purposes, should be implemented in a manner consistent with current community practice. The community practice was significantly impacted and revised during July 1999, after the Health Care Financing Administration defined rules for the use of seclusion and restraint in facilities that participate in Medicare and Medicaid. Since few correctional facilities are Medicare or Medicaid participants, these rules had little impact on the use of seclusion or restraint for mental health care purposes in correctional systems. Consequently, many correctional health care systems have not developed policies, procedures, or practices that are consistent with current community practice. This document provides guidance in remedying such problems, with a focus on areas relevant to timeframes, settings, and monitoring.     

Variation in the classification of polyneuropathies among European physicians.

OBJECTIVE: Considerable debate still exists regarding the classification of polyneuropathies (PNPs) into predominantly demyelinating, predominantly axonal loss, mixed or unclassified. This study was designed to determine the variation among physicians in the classification of PNPs by using the European Standardized Telematic tool to Evaluate Electromyography knowledge-based systems and Methods (ESTEEM) multicenter database. METHODS: Seven physicians from 6 laboratories in Europe sent a total of 156 prospectively collected cases of PNP with electromyography (EMG) data including diagnosis (examination diagnosis) to the database. Each physician interpreted the electrophysiological data from all cases (interpretation diagnosis) and a final diagnosis was given at the consensus meetings of the group (consensus diagnosis). RESULTS: Comparison of each physician's examination diagnosis with his/her interpretation diagnosis, i.e. intra-physician variation, showed a change towards less classified PNPs (P < 0.05). Interpretation diagnoses showed large inter-physician variation in the classification of PNPs. The consensus group was more cautious than individual physicians in classifying PNPs as mixed and axonal. The probability of the consensus diagnosis increased with increasing number of abnormal motor and sensory segments tested. CONCLUSIONS: Recognition of variation in classification of PNP as shown in this study and suggesting standards of good clinical practice developed by a consensus group may increase the quality of EMG practice.     

Simulation of EMG in pathological situations.

OBJECTIVE: A mathematical model for simulation of the EMG from a muscle with its motor units is used. The study aims at correlating EMG findings (single-fiber EMG and concentric-needle EMG) with various induced morphological changes. METHODS: Reinnervation has been simulated by removing motor units randomly followed by a complete reinnervation from adjacent surviving motor units. Fibre type grouping and grouped atrophy can be seen. Myopathy is simulated by increased fibre diameter variation, loss of fibres and muscle fibre splitting. RESULTS AND CONCLUSION: The simulation gives quantitative aspects of the importance of each of these factors. It indicates the relative sensitivity of various EMG parameters. The model can be used both for education and for research.     

Multivariate AR modeling of electromyography for the classification of upper arm movements.

OBJECTIVE: We compared the performance of two feature extraction methods for multichannel electromyography (EMG) based arm movement classification. One method was to use a scalar autoregressive model (sAR) for each channel. Another was to model all channels as a whole by a multivariate AR model (mAR). METHODS: The classified arm movements included elbow flexion, elbow extension, forearm pronation and internal shoulder rotation. Six-channel bipolar EMG signals were collected from four electrodes fixed on the biceps, triceps, brachioradialis and deltoid. Fifteen two-channel and four three-channel configurations were formed out of these six-channel signals for a comparison of different channel combinations. Leave-one-out cross-validation was adopted for evaluating the classification performance using a parametric statistical classifier. RESULTS: We processed a total of 216 EMG segments obtained from repeated 18 performances by three normal subjects. mAR model based feature set achieved a better classification accuracy than sAR did for each configuration. Moreover, significance of improvement was greater than 0.95 for those configurations which consisted of EMG channels that were close spatially. CONCLUSIONS: The stronger the cross-correlation among EMG channels the more improvement of classification accuracy one would expect from using a mAR model.     

Practice parameters: strategies for survival into the nineties.

In an atmosphere of escalating medical costs, clinical practice guidelines have been proposed as a viable means of achieving cost containment. The approaches to developing standards of practice have historically been varied, and new methods of development have been proposed to incorporate current scientific knowledge and patient preferences for achieving optimal health outcomes. We review the historical, governmental, and health organization approaches to achieve scientifically sound and clinically relevant parameters. The mechanism and the mission of the American Academy of Neurology Quality Standards Subcommittee is reviewed. The Subcommittee has selected the term "practice parameter" in lieu of "practice policy" to be consistent with AMA terminology. Practice parameters may include one or more of the following types of recommendations: standards, guidelines, and options. These three terms reflect varying levels of clinical certainty as determined by the level of objective evidence.     

Ultrasound in EMG‐Guided Biopsies: A Prospective,Randomized Pilot Trial

Introduction: At our institution, core muscle biopsies are performed on muscles selected using electromyography (EMG). Ultrasound (US) guidance is not used routinely. The aim of this study was to determine if US guidance of EMG selected muscles would increase the diagnostic yield of the biopsy as compared to the current practice standards. Methods: Two trained physicians performed 40 randomized biopsies (US guided or traditional approach). The amount of tissue obtained in each biopsy was recorded (volume and mass), along with the final pathologic diagnosis in each case and incidence of complications. Results: Forty patients were studied. Sixteen muscle biopsies were done with US guidance; 50% had a definitive diagnosis, and 38% did not. In the non‐US guidance group, 58% had a definitive diagnosis, and 33% did not. Conclusions: US did not provide any additive advantage when used to guide biopsy in a muscle previously selected for biopsy with EMG. Muscle Nerve 54 : 786–788, 2016     

Routine and sleep EEG: Minimum recording standards of the International Federation of Clinical Neurophysiology and the International League Against Epilepsy

This article provides recommendations on the minimum standards for recording routine (“standard”) and sleep electroencephalography (EEG). The joint working group of the International Federation of Clinical Neurophysiology (IFCN) and the International League Against Epilepsy (ILAE) developed the standards according to the methodology suggested for epilepsy-related clinical practice guidelines by the Epilepsy Guidelines Working Group. We reviewed the published evidence using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. The quality of evidence for sleep induction methods was assessed by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) method. A tool for Quality Assessment of Diagnostic Studies (QUADAS-2) was used to assess the risk of bias in technical and methodological studies. Where high-quality published evidence was lacking, we used modified Delphi technique to reach expert consensus. The GRADE system was used to formulate the recommendations. The quality of evidence was low or moderate. We formulated 16 consensus-based recommendations for minimum standards for recording routine and sleep EEG. The recommendations comprise the following aspects: indications, technical standards, recording duration, sleep induction, and provocative methods.     

Misdiagnosis of mitochondrial myopathies: a study of 12 thymectomized patients

INTRODUCTION: Myasthenia gravis and mitochondrial myopathies have common symptoms (fatigability, ophthalmoplegia) that could lead to diagnosis confusion. METHODS: We systematically reviewed medical history and ancillary investigations regarding 12 patients (7F/5M, mean age 47+/-14 years) having a mitochondrial myopathy but who were previously misdiagnosed as autoimmune myasthenia gravis and in whom a thymectomy was performed. RESULTS: Ocular palsy, ptosis and bulbar palsy were present in all patients. Limb fatigability was present in 9 cases. Symptoms were fluctuant but without remission. The misdiagnosis of myasthenia was based on the following arguments: 1) decremental EMG response (2 cases); 2) positive injectable anticholinesterase drugs test (3 cases); 3) partial response to oral anticholinesterase medications (2 cases); 4) AChR antibodies titer of 0.6 nM considered as positive (1 case). A multisystemic involvement was present in 5 patients: peripheral neuropathy (2 cases), deafness (2 cases), cardiopathy (3 cases), cerebellar involvement (2 cases) and myoclonia (1 case). The diagnosis of mitochondrial myopathy (at a mean age of 38+/-12 years) has been certified on the results of muscle biopsy showing mitochondrial proliferation (12 cases) and deleted mitochondrial DNA (8 cases). CONCLUSIONS: In a patient presenting with oculomotor symptoms and muscle fatigability, progressive course and multisystemic involvement are major arguments for a mitochondrial myopathy. In the absence of relevant criteria arguing for Myasthenia Gravis (significant variability of muscle weakness, positive titer of anti-AChR or anti-MuSK antibodies, decremental EMG response), a muscle biopsy is required before indication of thymectomy to exclude a mitochondrial disease.     

Objectives and methodology: Guidelines of the Italian Society for Haemostasis and Thrombosis (SISET)

A current goal of the Italian Society for Thrombosis and Haemostasis (SISET) is the production of guidelines for clinical conditions related to haemostasis and thrombosis. In 2006, the Executive Committee of SISET adopted a new program for the production of methodologically and scientifically sound guidelines aimed at both addressing clinical practice and stimulating new research. The first major step for this program was to train methodologists to manage working groups that compose the guidelines, and to create a reference document that describes the development of the program. The aim of the present paper is to report a short version of this methodological document, for those who wish to follow SISET guidelines. We start by giving a brief outline of the SISET mission, then present the SISET guideline development process, which includes: project funding, selection of guidelines topics, multidisciplinary group composition, definition of clinical questions, literature search, evidence appraisal, grading recommendations, guideline implementation, external peer review, and guideline updating.     

Treatment of eczema by EMG biofeedback and relaxation training: a multiple baseline analysis

Five adults who suffered from eczema for at least five years were treated in a multiple baseline design with EMG biofeedback and progressive relaxation. Treatment consisted of five weekly EMG training sessions combined with regular home practice of relaxation. Three dependent measures were used to assess treatment effects: (1) daily self-monitoring of symptom irritation levels, (2) pre and post assessments of eczema affected areas and (3) the Spielberger Trait Anxiety Questionnaire which was also administered on a pre-post basis. Results showed clinically meaningful improvements in all five participants which were maintained at a two month follow-up. A second follow-up two years later showed that three of subjects were asymptomatic. The other two subjects could not be located. Taken together, the study provides evidence that EMG biofeedback combined with home practice of progressive relaxation can help to reduce the severity of eczema and the irritation associated with the disorder.     

Standards of instrumentation of EMG

Standardization of Electromyography (EMG) instrumentation is of particular importance to ensure high quality recordings. This consensus report on “Standards of Instrumentation of EMG” is an update and extension of the earlier IFCN Guidelines published in 1999. First, a panel of experts in different fields from different geographical distributions was invited to submit a section on their particular interest and expertise. Then, the merged document was circulated for comments and edits until a consensus emerged.The first sections in this document cover technical aspects such as instrumentation, EMG hardware and software including amplifiers and filters, digital signal analysis and instrumentation settings. Other sections cover the topics such as temporary storage, trigger and delay line, averaging, electrode types, stimulation techniques for optimal and standardised EMG examinations, and the artefacts electromyographers may face and safety rules they should follow. Finally, storage of data and databases, report generators and external communication are summarized.     

Determining disability due to mental impairment: APA's evaluation of Social Security Administration guidelines

OBJECTIVE: APA evaluated the Social Security Administration's (SSA's) medical standards and guidelines for determining disability due to mental impairment to determine how well the standards and guidelines operationalize the statutory definition of disability in a manner consistent with current psychiatric practice. METHOD: Seventy-two psychiatrists were trained in one of two procedures: those in the sequential evaluation condition were trained in the process and forms used by the SSA's reviewing medical consultants, and those in the statutory definition condition were trained in the statutory definition of disability and application of clinical judgment according to this standard. Decisions regarding claimant's ability or inability to work were recorded on an instrument designed for the study. Each condition consisted of 12 panels of three members. They reviewed 732 actual claims for disability benefits. The panelists reviewed claims independently, then rendered panel judgments. Each claim was reviewed by one panel in each condition. RESULTS: The proportion of agreement between conditions for panel decisions (0.77) was higher than chance agreement (kappa = 0.46). The high level of agreement on claims judged to have good medical evidence and on which confident decisions were made (proportion of agreement = 0.96, kappa = 0.78) suggests that disagreements largely reflected ambiguities in application of the standards and guidelines to more complex cases or those with inadequate information. CONCLUSIONS: The SSA's revised medical standards and guidelines reflect clinical decisions about ability to work based on the statute and, with procedural modifications, should be retained. The SSA should be involved in further systematic studies to develop a field of scientific inquiry into disability and psychiatric disorders.     

Mandating education of dental graduates to provide care to individuals with intellectual and developmental disabilities

In 2004, The Commission on Dental Accreditation adopted new standards for dental and dental hygiene education programs to ensure the preparation of practitioners to provide oral health services for persons with special health care needs. The course of action leading to the adoption of the new standards, together with the continuing obstacles of limited government support for dental services and the availability of faculty members to provide the needed dental educational experiences is reviewed. Expanding Health Resources and Services Administration definition of medically underserved areas is presented as one approach to improving the delivery of dental services.     

American Academy of Clinical Neuropsychology (AACN) practice guidelines for neuropsychological assessment and consultation

This document is the first set of practice guidelines to be formally reviewed and endorsed by the AACN Board of Directors and published in the official journal of AACN. They have been formulated with the assumption that guidelines and standards for neuropsychological assessment and consultation are essential to professional development. As such, they are intended to facilitate the continued systematic growth of the profession of clinical neuropsychology, and to help assure a high level of professional practice. These guidelines are offered to serve members of AACN, as well as the field of clinical neuropsychology as a whole.     

American Academy of Clinical Neuropsychology (AACN) Practice Guidelines for Neuropsychological Assessment and Consultation

This document is the first set of practice guidelines to be formally reviewed and endorsed by the AACN Board of Directors and published in the official journal of AACN. They have been formulated with the assumption that guidelines and standards for neuropsychological assessment and consultation are essential to professional development. As such, they are intended to facilitate the continued systematic growth of the profession of clinical neuropsychology, and to help assure a high level of professional practice. These guidelines are offered to serve members of AACN, as well as the field of clinical neuropsychology as a whole.