Michael Swash | Queen Mary, University of London (original) (raw)
Papers by Michael Swash
Contributions to Contemporary Neurology, 1988
Publisher Summary This chapter discusses amyotrophic lateral sclerosis. This disease accounts for... more Publisher Summary This chapter discusses amyotrophic lateral sclerosis. This disease accounts for about 0.1% of adult deaths and has an incidence of about 1.4 per 100,000. The prognosis is dependent largely on the severity of bulbar involvement. It is found that patients in whom there was predominant bulbar involvement survived for a mean of 2.2 years, whereas those with mainly spinal signs survived for as long as 3.3 years. It is found that the earlier the age of onset the longer the survival. Focal wasting during the early stages of the disease is often distal. It is uncommon for the clinician to observe the wasting of muscles around the shoulder or pelvic girdle at presentation, but the wasting of a hand or a foot is characteristic. Presentation with the weakness of axial or respiratory muscles is also uncommon, and bulbar wasting is less frequent than distal limb atrophy. It is found that either side may be affected or there is no correlation with handedness.
Publisher Summary This chapter discusses the role for neurophysiological methods in the diagnosis... more Publisher Summary This chapter discusses the role for neurophysiological methods in the diagnosis and management of motor neuron diseases (MNDs). The major components to clinical neurophysiology are motor and sensory nerve conduction studies, electromyography, and motor and multimodal sensory evoked potential studies—all electrophysiological techniques. Clinical neurophysiology is in a phase of rapid change, involving major alterations in its role in neurological research. There is a major unmet need in measurement of clinical change that requires the use of methods with very low intrinsic variance. The potential tide of change is well exemplified by the needs of clinicians in managing amyotrophic lateral sclerosis (ALS) and other motor neuron disorders. In MNDs where a decline in function is the norm, serial measures will enable future therapies to be controlled and assessed more accurately. Many conventional clinical neurophysiological techniques and the motor unit number estimati...
Http Www Libreriasaulamedica Com, 2006
Paediatric Pathology, 1989
The histological study of muscle and peripheral nerve forms a major part of paediatric pathology ... more The histological study of muscle and peripheral nerve forms a major part of paediatric pathology since neuromuscular disorders are common problems. Modern histopathological techniques have led to greater understanding of these disorders and thus to a more rational and hopeful approach to diagnosis and treatment. Naturally, new problems and controversies have also arisen.
Neuromuscular Diseases, 1997
Neuromuscular diseases have become better understood as knowledge of the basic processes of neuro... more Neuromuscular diseases have become better understood as knowledge of the basic processes of neuromuscular function, especially transmission of nervous impulses, the function of the neuromuscular junction and the physical and biochemical processes of muscular contraction, has increased. Indeed, some neuromuscular disorders have themselves led to insights into these basic mechanisms. Huxley (1986) has reviewed the historical background of discoveries in relation to muscular contraction.
Pediatric Surgery International, 1987
Thirty incontinent patients with corrected high ano-rectal anomalies were studied using concentri... more Thirty incontinent patients with corrected high ano-rectal anomalies were studied using concentric needle electromyography (EMG) 'sphincter mapping'. The findings were correlated with the ability to excite the external anal sphincter by transrectal pudendal nerve stimulation in 13 cases. EMG evidence of a functional external anal sphincter was found in 22 patients, but this was either to one side of or completely separate from the surgically created anal orifice in 17 cases. No activity could be detected in 8 cases without complex anomalies, a much higher incidence than in a previous series of children examined pre-operatively. This suggests damage to the sphincter during primary corrective surgery. These combined neurophysiological techniques are useful in the assessment of incontinent children with corrected high ano-rectal anomalies, even though striated sphincter function is not the sole consideration in establishing continence.
Journal of Neurology, Neurosurgery & Psychiatry, 1989
The following M MD, Ignatius Ziekenhuis, Willhelminpatients were excluded: (1) 21 (18%) because a... more The following M MD, Ignatius Ziekenhuis, Willhelminpatients were excluded: (1) 21 (18%) because asingel 33, 4817 JX Breda, The Netherlands. signs and symptoms indicative for multiple sclerosis were already present, (2) 14 (12%) Referefes without VER abnormalities (5/14 turned out Cohen MM, Lessell S, Wole PA. A prospective to be hysteric) and (3) 19 (16%) with study of the risk of developing Multiple insufficient clinical data. The remaining 64 Sclerosis in uncomplicated Optic Neuritis. patients all had a history of rapidly progres
Neuromuscular Diseases, 1997
Paediatric Pathology, 1981
Neurobiology of Disease, 2007
The term hereditary spastic paraplegia (HSP) defines a clinically and genetically heterogeneous g... more The term hereditary spastic paraplegia (HSP) defines a clinically and genetically heterogeneous group of inherited neurological disorders characterized by progressive symmetrical spasticity and weakness of the lower limbs. The phenotype is classified as pure if symptoms and signs are confined to progressive spastic paraparesis, with occasional posterior column or bladder involvement, or complicated if major additional neurological or other features are present. Inheritance may be autosomal dominant (AD), autosomal recessive (AR), or X-linked for both pure and complicated forms. Primary lateral sclerosis (PLS) is a variant of amyotrophic lateral sclerosis (ALS), in which the predominant feature is progressive spastic weakness involving spinal regions and usually pseudobulbar features. Advances in the identification of causative genes have increased the understanding of a number of overlapping molecular mechanisms underlying the various forms of HSP. Disruption of the corticospinal pathways, manifesting in a spastic paraparesis, may result from either abnormal initial development or subsequent neurodegeneration. At present, there are no disease-modifying treatments for patients with HSP, and no clinical trials are available regarding the possible effect of riluzole in PLS. All these syndromes show progressive disability.
Neuromuscular Diseases, 1997
Neuromuscular Diseases, 1997
Techniques in Coloproctology, 2012
Background The aim of this study was to test our hypothesis that the reason why imaging is of lit... more Background The aim of this study was to test our hypothesis that the reason why imaging is of little assistance in diagnosing ''constipation'' causes may be related to the high sensitivity of internal anorectal flow resistance in defecation to small changes in geometry. We applied a mathematical model to describe the effects on flow mechanics of observed changes in the shape of the rectum and anus during defecation. Methods Three groups of patients were studied with video proctograms. Group 1 comprised 4 patients with Keywords Mechanism of defecation Á Constipation Á Fecal incontinence Á Pelvic floor disorders Á Anorectal resistance Á Lubricated flow Á Yield stress Á Mathematical model M. Bush (&) Á P.
Journal of Neurology, Neurosurgery & Psychiatry, 2010
Physicians frequently note that patients with motor neuron disease (MND)/amyotrophic lateral scle... more Physicians frequently note that patients with motor neuron disease (MND)/amyotrophic lateral sclerosis appear undistressed, and may even report a high level of quality of life, despite their evident severe disability. Sometimes this can be attributed to an associated frontotemporal dementia, especially when there is apathy, bland indifference, blunting of emotion or self-centredness.1 In others, depression is a feature, perhaps understandable to the observer or carer, and associated with despair and even a wish to hasten death. Understanding the process of psychosocial adjustment to chronic illness is an important aspect of holistic and palliative care during the course of the disease. It is a complex process that, perhaps surprisingly, does not depend …
Journal of Neurology, Neurosurgery & Psychiatry, 1984
Neuromuscular Disorders, 1992
Clinical criteria for the diagnosis of motor neuron disease, agreed at the inaugural meeting of t... more Clinical criteria for the diagnosis of motor neuron disease, agreed at the inaugural meeting of the European Familial Amyotrophic Lateral Sclerosis Collaborative Group, are described. The criteria are derived from those developed for the study of sporadic amyotrophic lateral sclerosis, and allow the inclusion of certain recognized clinical sub-types of familial amyotrophic lateral sclerosis. They will require testing for consistency and sensitivity.
Clinical Neuropathology, 1983
The development of new techniques for the histological study of muscle has led to fresh concepts ... more The development of new techniques for the histological study of muscle has led to fresh concepts of the pathogenesis and classification of neuromuscular disorders. In this chapter a general account of the pathological reactions of muscle will be given, particularly in relation to biopsy material, although some attention will also be given to autopsy findings. The features of individual disorders will be summarised.
Techniques in Coloproctology, 2012
Background We conducted an observational study to assess the hypothesis that the pelvic muscles a... more Background We conducted an observational study to assess the hypothesis that the pelvic muscles actively open the anorectal lumen during defecation. Methods Three groups of female patients were evaluated with video imaging studies of defecation using a grid or bony reference points. Eight patients with idiopathic fecal incontinence had video myogram defecography; eight with obstructive defecation had magnetic resonance imaging (MRI) defecating proctograms; and four normal patients had video X-ray or MRI defecating proctogram studies. Results In all three groups, the anorectum was stretched bidirectionally by three directional muscle force vectors acting on the walls of the rectum, effectively doubling the diameter of the rectum during defecation. The anterior rectal wall was pulled forwards, and the posterior wall backwards and downwards opening the anorectal angle, associated with angulation of the anterior tip of the levator plate (LP). These observations are consistent with a staged relaxation of some parts of the pelvic floor during defecation, and contraction of others. First, the puborectalis muscle relaxes. Puborectalis muscle relaxation frees the posterior rectal wall so that it can be stretched and opened by contraction of the LP and conjoint longitudinal muscle of the anus. Second, contraction of the pubococcygeus muscle pulls forward the anterior rectal wall, further increasing the diameter of the rectum. Third, when the bolus has entered the rectum, the external anal sphincter relaxes, and the rectum contracts to expel the fecal bolus. Conclusions Our results are consistent with the hypothesis that pelvic striated muscle actively opens the rectal lumen, thereby reducing internal anorectal resistance to expulsion of feces. Controlled studies of electromyographic activity would be useful to further test this hypothesis.
Contributions to Contemporary Neurology, 1988
Publisher Summary This chapter discusses amyotrophic lateral sclerosis. This disease accounts for... more Publisher Summary This chapter discusses amyotrophic lateral sclerosis. This disease accounts for about 0.1% of adult deaths and has an incidence of about 1.4 per 100,000. The prognosis is dependent largely on the severity of bulbar involvement. It is found that patients in whom there was predominant bulbar involvement survived for a mean of 2.2 years, whereas those with mainly spinal signs survived for as long as 3.3 years. It is found that the earlier the age of onset the longer the survival. Focal wasting during the early stages of the disease is often distal. It is uncommon for the clinician to observe the wasting of muscles around the shoulder or pelvic girdle at presentation, but the wasting of a hand or a foot is characteristic. Presentation with the weakness of axial or respiratory muscles is also uncommon, and bulbar wasting is less frequent than distal limb atrophy. It is found that either side may be affected or there is no correlation with handedness.
Publisher Summary This chapter discusses the role for neurophysiological methods in the diagnosis... more Publisher Summary This chapter discusses the role for neurophysiological methods in the diagnosis and management of motor neuron diseases (MNDs). The major components to clinical neurophysiology are motor and sensory nerve conduction studies, electromyography, and motor and multimodal sensory evoked potential studies—all electrophysiological techniques. Clinical neurophysiology is in a phase of rapid change, involving major alterations in its role in neurological research. There is a major unmet need in measurement of clinical change that requires the use of methods with very low intrinsic variance. The potential tide of change is well exemplified by the needs of clinicians in managing amyotrophic lateral sclerosis (ALS) and other motor neuron disorders. In MNDs where a decline in function is the norm, serial measures will enable future therapies to be controlled and assessed more accurately. Many conventional clinical neurophysiological techniques and the motor unit number estimati...
Http Www Libreriasaulamedica Com, 2006
Paediatric Pathology, 1989
The histological study of muscle and peripheral nerve forms a major part of paediatric pathology ... more The histological study of muscle and peripheral nerve forms a major part of paediatric pathology since neuromuscular disorders are common problems. Modern histopathological techniques have led to greater understanding of these disorders and thus to a more rational and hopeful approach to diagnosis and treatment. Naturally, new problems and controversies have also arisen.
Neuromuscular Diseases, 1997
Neuromuscular diseases have become better understood as knowledge of the basic processes of neuro... more Neuromuscular diseases have become better understood as knowledge of the basic processes of neuromuscular function, especially transmission of nervous impulses, the function of the neuromuscular junction and the physical and biochemical processes of muscular contraction, has increased. Indeed, some neuromuscular disorders have themselves led to insights into these basic mechanisms. Huxley (1986) has reviewed the historical background of discoveries in relation to muscular contraction.
Pediatric Surgery International, 1987
Thirty incontinent patients with corrected high ano-rectal anomalies were studied using concentri... more Thirty incontinent patients with corrected high ano-rectal anomalies were studied using concentric needle electromyography (EMG) 'sphincter mapping'. The findings were correlated with the ability to excite the external anal sphincter by transrectal pudendal nerve stimulation in 13 cases. EMG evidence of a functional external anal sphincter was found in 22 patients, but this was either to one side of or completely separate from the surgically created anal orifice in 17 cases. No activity could be detected in 8 cases without complex anomalies, a much higher incidence than in a previous series of children examined pre-operatively. This suggests damage to the sphincter during primary corrective surgery. These combined neurophysiological techniques are useful in the assessment of incontinent children with corrected high ano-rectal anomalies, even though striated sphincter function is not the sole consideration in establishing continence.
Journal of Neurology, Neurosurgery & Psychiatry, 1989
The following M MD, Ignatius Ziekenhuis, Willhelminpatients were excluded: (1) 21 (18%) because a... more The following M MD, Ignatius Ziekenhuis, Willhelminpatients were excluded: (1) 21 (18%) because asingel 33, 4817 JX Breda, The Netherlands. signs and symptoms indicative for multiple sclerosis were already present, (2) 14 (12%) Referefes without VER abnormalities (5/14 turned out Cohen MM, Lessell S, Wole PA. A prospective to be hysteric) and (3) 19 (16%) with study of the risk of developing Multiple insufficient clinical data. The remaining 64 Sclerosis in uncomplicated Optic Neuritis. patients all had a history of rapidly progres
Neuromuscular Diseases, 1997
Paediatric Pathology, 1981
Neurobiology of Disease, 2007
The term hereditary spastic paraplegia (HSP) defines a clinically and genetically heterogeneous g... more The term hereditary spastic paraplegia (HSP) defines a clinically and genetically heterogeneous group of inherited neurological disorders characterized by progressive symmetrical spasticity and weakness of the lower limbs. The phenotype is classified as pure if symptoms and signs are confined to progressive spastic paraparesis, with occasional posterior column or bladder involvement, or complicated if major additional neurological or other features are present. Inheritance may be autosomal dominant (AD), autosomal recessive (AR), or X-linked for both pure and complicated forms. Primary lateral sclerosis (PLS) is a variant of amyotrophic lateral sclerosis (ALS), in which the predominant feature is progressive spastic weakness involving spinal regions and usually pseudobulbar features. Advances in the identification of causative genes have increased the understanding of a number of overlapping molecular mechanisms underlying the various forms of HSP. Disruption of the corticospinal pathways, manifesting in a spastic paraparesis, may result from either abnormal initial development or subsequent neurodegeneration. At present, there are no disease-modifying treatments for patients with HSP, and no clinical trials are available regarding the possible effect of riluzole in PLS. All these syndromes show progressive disability.
Neuromuscular Diseases, 1997
Neuromuscular Diseases, 1997
Techniques in Coloproctology, 2012
Background The aim of this study was to test our hypothesis that the reason why imaging is of lit... more Background The aim of this study was to test our hypothesis that the reason why imaging is of little assistance in diagnosing ''constipation'' causes may be related to the high sensitivity of internal anorectal flow resistance in defecation to small changes in geometry. We applied a mathematical model to describe the effects on flow mechanics of observed changes in the shape of the rectum and anus during defecation. Methods Three groups of patients were studied with video proctograms. Group 1 comprised 4 patients with Keywords Mechanism of defecation Á Constipation Á Fecal incontinence Á Pelvic floor disorders Á Anorectal resistance Á Lubricated flow Á Yield stress Á Mathematical model M. Bush (&) Á P.
Journal of Neurology, Neurosurgery & Psychiatry, 2010
Physicians frequently note that patients with motor neuron disease (MND)/amyotrophic lateral scle... more Physicians frequently note that patients with motor neuron disease (MND)/amyotrophic lateral sclerosis appear undistressed, and may even report a high level of quality of life, despite their evident severe disability. Sometimes this can be attributed to an associated frontotemporal dementia, especially when there is apathy, bland indifference, blunting of emotion or self-centredness.1 In others, depression is a feature, perhaps understandable to the observer or carer, and associated with despair and even a wish to hasten death. Understanding the process of psychosocial adjustment to chronic illness is an important aspect of holistic and palliative care during the course of the disease. It is a complex process that, perhaps surprisingly, does not depend …
Journal of Neurology, Neurosurgery & Psychiatry, 1984
Neuromuscular Disorders, 1992
Clinical criteria for the diagnosis of motor neuron disease, agreed at the inaugural meeting of t... more Clinical criteria for the diagnosis of motor neuron disease, agreed at the inaugural meeting of the European Familial Amyotrophic Lateral Sclerosis Collaborative Group, are described. The criteria are derived from those developed for the study of sporadic amyotrophic lateral sclerosis, and allow the inclusion of certain recognized clinical sub-types of familial amyotrophic lateral sclerosis. They will require testing for consistency and sensitivity.
Clinical Neuropathology, 1983
The development of new techniques for the histological study of muscle has led to fresh concepts ... more The development of new techniques for the histological study of muscle has led to fresh concepts of the pathogenesis and classification of neuromuscular disorders. In this chapter a general account of the pathological reactions of muscle will be given, particularly in relation to biopsy material, although some attention will also be given to autopsy findings. The features of individual disorders will be summarised.
Techniques in Coloproctology, 2012
Background We conducted an observational study to assess the hypothesis that the pelvic muscles a... more Background We conducted an observational study to assess the hypothesis that the pelvic muscles actively open the anorectal lumen during defecation. Methods Three groups of female patients were evaluated with video imaging studies of defecation using a grid or bony reference points. Eight patients with idiopathic fecal incontinence had video myogram defecography; eight with obstructive defecation had magnetic resonance imaging (MRI) defecating proctograms; and four normal patients had video X-ray or MRI defecating proctogram studies. Results In all three groups, the anorectum was stretched bidirectionally by three directional muscle force vectors acting on the walls of the rectum, effectively doubling the diameter of the rectum during defecation. The anterior rectal wall was pulled forwards, and the posterior wall backwards and downwards opening the anorectal angle, associated with angulation of the anterior tip of the levator plate (LP). These observations are consistent with a staged relaxation of some parts of the pelvic floor during defecation, and contraction of others. First, the puborectalis muscle relaxes. Puborectalis muscle relaxation frees the posterior rectal wall so that it can be stretched and opened by contraction of the LP and conjoint longitudinal muscle of the anus. Second, contraction of the pubococcygeus muscle pulls forward the anterior rectal wall, further increasing the diameter of the rectum. Third, when the bolus has entered the rectum, the external anal sphincter relaxes, and the rectum contracts to expel the fecal bolus. Conclusions Our results are consistent with the hypothesis that pelvic striated muscle actively opens the rectal lumen, thereby reducing internal anorectal resistance to expulsion of feces. Controlled studies of electromyographic activity would be useful to further test this hypothesis.