Urodynamic analysis in multiple system atrophy: characterisation of detrusor-sphincter dyssynergia

In multiple system atrophy (MSA), parkinsonism and a cerebellar syndrome are associated with autonomic dysfunction. Both bladder neck dysfunction and external sphincter denervation have been implicated in detrusor-sphincter dyssynergia. However, urethral dysfunction may not be adequately reflected by a single global measurement of urethral pressure. Pressure assessment at several levels of the urethra is needed to unravel the mechanisms of bladder-urethra dysfunction. Here, we evaluated the use of multiple sensor pressure transducers to assess bladder-sphincter function in 52 patients with MSA in comparison to patients with Parkinson’s disease (PD) who were matched for age and severity in the “off” condition. Urinary dysfunction appeared significantly earlier in MSA (<2 years) than in PD (>5 years). Detrusor under-activity with dysuria was observed in 58% of MSA patients within 4 years and in 76% of patients thereafter. Detrusor-urethral dyssynergia in MSA patients was always better characterized by multiple sensor pressure transducer measurement of bladder and urethral pressure than by a single global measurement. This new approach may prove useful for differential diagnosis of parkinsonian syndromes, and especially MSA.     

Micturitional disturbance in pure autonomic failure

We obtained micturitional histories and performed urodynamic studies in six patients with pure autonomic failure. All patients had urinary symptoms. Urodynamic studies showed postmicturition residuals in two, small bladder capacities in two, detrusor hyperreflexia in four, low bladder compliance in two, detrusor-external sphincter dyssynergia in one, neurogenic sphincter electromyography in three, and denervation supersensitivity of the bladder in two. Micturitional disturbance is a common feature in pure autonomic failure because of peripheral and central types of abnormalities.     

Colonic transit time, sphincter EMG, and rectoanal videomanometry in multiple system atrophy.

Both constipation and fecal incontinence are prominent lower gastrointestinal tract (LGIT) dysfunctions that occur frequently in multiple system atrophy (MSA). We investigated the mechanism of constipation and fecal incontinence in MSA. Colonic transit time (CTT), sphincter electromyography (EMG), and rectoanal videomanometry were performed in 15 patients with MSA (10 men, 5 women; mean age, 63.5 years; mean duration of disease, 3 years; decreased bowel frequency [< 3 times a week] in 9; difficulty in expulsion in 11; fecal incontinence in 3) and 10 age-matched healthy control subjects (7 men and 3 women; mean age, 62 years; decreased bowel frequency in 2; mild difficulty in expulsion in 2; fecal incontinence in none). Compared to the control subjects, MSA patients had significantly prolonged CTT in the rectosigmoid segment and total colon. Sphincter EMG showed neurogenic motor unit potentials in none of control subjects but in 93% of MSA patients. At the resting state, MSA patients showed a lower anal squeeze pressure (external sphincter weakness) and a smaller increase in abdominal pressure on coughing. During rectal filling, MSA patients showed smaller amplitude in phasic rectal contraction, which was accompanied by an increase in anal pressure that normally decreased, together with leaking in 3 patients. During defecation, most MSA patients could not defecate completely and had larger postdefecation residuals. MSA patients had weak abdominal strain, smaller rectal contraction on defecation, and larger anal contraction on defecation (paradoxical sphincter contraction on defecation), although these differences were not statistically significant. These findings in MSA patients were similar to those in Parkinson's disease patients in our previous study, except for the sphincter denervation and weakness in MSA. Constipation in MSA most probably results from slow colonic transit, decreased phasic rectal contraction, and weak abdominal strain, and fecal incontinence results from weak anal sphincter due to denervation. The responsible sites for these dysfunctions seem to be both central and peripheral nervous systems that regulate the LGIT.     

When is Onuf's nucleus involved in multiple system atrophy? A sphincter electromyography study

BACKGROUND: External anal sphincter (EAS) electromyography (EMG) abnormalities can distinguish multiple system atrophy (MSA) from Parkinson's disease in the first five years after disease onset. However, the prevalence of the abnormalities in the early stages of MSA is unknown. OBJECTIVES: To present EAS-EMG data in the various stages of MSA. METHODS: 84 patients with "probable" MSA were recruited (42 men, 42 women; mean age 62 years (range 47 to 78); mean disease duration 3.2 years (0.5 to 8.0; <1 year in 25%); 50 cerebellar form (MSA-C), 34 parkinsonian form (MSA-P)). EAS motor unit potential (MUP) analysis and EMG cystometry were carried out in all patients. RESULTS: The overall prevalence of neurogenic change of the EAS MUP was 62%-52% in the first year after disease onset, increasing to 83% by the fifth year (p<0.05); it also increased with severity of gait disturbance (p<0.05), storage and voiding disorders, and detrusor sphincter dyssynergy (NS). The neurogenic change was not correlated with sex, age, MSA-P/C, postural hypotension, constipation, erectile dysfunction in men, underactive or acontractile detrusor, or detrusor overactivity. In 17 incontinent patients without detrusor overactivity or low compliance, urinary incontinence was more severe in those with neurogenic change than in those without (p<0.05). CONCLUSIONS: Involvement of Onuf's nucleus in MSA is time dependent. Before the fifth year of illness, the prevalence of neurogenic change does not seem to be high, so a negative result cannot exclude the diagnosis of MSA.     

Lower urinary tract dysfunction in Machado-Joseph disease: a study of 11 clinical-urodynamic observations

OBJECTIVES: Machado-Joseph disease (MJD), or hereditary spinocerebellar ataxia type 3, is the most common dominantly inherited ataxia. However, lower urinary tract (LUT) dysfunction in MJD has not been fully delineated. We investigated LUT dysfunction in MJD by clinical-urodynamic observations. METHODS: In 24 genetically diagnosed MJD, we recruited all 11 patients with LUT symptoms (six men, five women; age, 18-61 [mean 48] years; disease duration, 2-24 [mean 9] years; voiding difficulty, 7, urinary incontinence, 4). Urodynamic studies consisted of uroflowmetry, measurement of post-void residuals and electromyography (EMG)-cystometry. Neurophysiology tests consisted of motor unit potential (MUP) analysis of the sphincter and extremity muscles, tibial nerve somatosensory evoked potentials (SEP) and nerve conduction studies (NCS) of the extremities. RESULTS: Urodynamic abnormalities were seen in all 11 patients studied. Maximum or average flow rate was decreased in five. Post-void residual was noted in three but residual urine volume > 100 ml was noted in only one patient. Maximum urethral closure pressure was low in one and high in one of five patients studied. EMG-cystometry during filling showed detrusor overactivity in five, impaired bladder sensation in four, low compliance detrusor in one, uninhibited sphincter relaxation in one and incompetent urethra in one. Voiding phase abnormalities included detrusor areflexia in three and detrusor-sphincter dyssynergia in two. Bethanechol supersensitivity of the bladder was noted in one of three patients studied. Bulbocavernosus reflex was absent in two of five patients studied. MUP analysis showed neurogenic changes in six of nine sphincter muscles and in all six extremity muscles studied. Five patients had prolonged or absent cortical response in SEP and four had sensory axonal neuropathy in NCS, which were relevant to the impaired bladder sensation. CONCLUSION: In the present study, a half of MJD patients had LUT symptoms and they showed various urodynamic abnormalities. Detrusor overactivity, impaired bladder sensation, and neurogenic sphincter EMG were common findings, and large post-void residuals were rare. These findings are relevant to central and peripheral nervous system pathology of MJD.     

Neurogenic failures of the external urethral sphincter closure and relaxation; a videourodynamic study

Urinary urgency and voiding difficulty are common features in neurological diseases, which can be attributed to dysfunction of the urethral sphincter and the detrusor. However, little is known about dynamic sphincter behaviour in neurological diseases. The present study aimed at investigating neurogenic failures of the external urethral sphincter closure and relaxation by videourodynamic study. We recruited 44 neurological patients with urinary urgency and frequency, 27 men and 17 women, mean age 61 years, and 28 of them had voiding difficulty as well. None had abnormal finding of digital examination or ultrasound echography of the pelvic organs. Using triple-lumen 7F catheter under X-ray fluoroscope, we measured detrusor pressure, external urethral sphincter pressure (Pura) and external sphincter EMG in all patients. We also performed pressure-flow study and obtained the Abram-Griffiths (AG) number, a numerical grade of obstruction. During filling 30 had detrusor hyperreflexia. EMG-cystometry showed uninhibited external sphincter relaxation (UESR) in eight patients, seven of whom had detrusor hyperreflexia as well. Patients with UESR showed an abnormal reduction of Pura, mean reduction 64 +/- 27 cmH2O (mean +/- standard deviation). During UESR the Pura and EMG activity fluctuated, and fluoroscopic image showed bladder neck opening in four with extreme urge sensation, including one without detrusor hyperreflexia. During an attempt of voiding three patients with voiding difficulty had detrusor-external sphincter dyssynergia (DESD) with detrusor contraction and eight had unrelaxing external sphincter without detrusor contraction. Fluoroscopic image showed an incomplete or absent urethral opening at the external sphincter. Four of them had severe straining on voiding together with intermittent increment of EMG activity without a normal funneling of the bladder neck. The mean reduction of Pura during voiding was 6.4 +/- 6.7 cmH2O and 5.0 +/- 9.5 cmH2O (in women and men, respectively) with DESD or unrelaxing external sphincter which was less than 39 +/- 25 cmH2O and 53 +/- 47 cmH2O in those without (P < 0.01). The mean AG number was 15 +/- 21 and 51 +/- 19 (for women and men, respectively) with DESD or unrelaxing external sphincter which was larger than 6.2 +/- 34 and 35 +/- 22 in those without (P < 0.05). In conclusion, UESR and DESD/unrelaxing external sphincter could be a factor for urinary urgency and voiding difficulty in neurological patients, evidence of central dysregulation affecting the Onuf's nucleus and its fibres to the external urethral sphincter.     

Electromyography of the external anal sphincter in patients with Parkinson's disease and multiple system atrophy: Frequency of abnormal spontaneous activity and polyphasic motor unit potentials

Electromyographic studies of the external anal sphincter muscle have received increasing attention in the differential diagnosis of patients with parkinsonism. Based on the fact that the external anal sphincter muscle is partly innervated by fibers that originate in Onuf's nucleus in the segments S2–S4 of the spinal cord, an increased duration of the motor unit potentials (MUPs) and an increased polyphasia may reflect neuronal loss of these lower motor neurons characteristic for multiple system atrophy. We report the results of anal sphincter electromyography in 15 patients with clinically probable multiple system atrophy (MSA) and 10 patients with Parkinson's disease (PD). There was no significant difference between patients with MSA and patients with PD concerning the duration of MUPs, mean number of phases, and rate of polyphasic motor potentials. There was a tendency for a longer mean duration and increased polyphasia in patients with MSA compared to patients with PD. Spontaneous activity was recorded in 11 of 15 patients with MSA occurring especially in patients with MSA of the striatonigral type, but not in patients with PD. In this study, the duration of MUPs and the rate of polyphasia were unreliable criteria in the electrophysiological differential diagnosis of patients with parkinsonism. Abnormal spontaneous activity, although difficult to detect, is a more specific marker for neuronal degeneration of Onuf's nucleus occurring in patients with MSA. © 1997 John Wiley & Sons, Inc. Muscle Nerve 20:1167–1172, 1997     

How to diagnose MSA early: the role of sphincter EMG

Summary. Multiple system atrophy (MSA) is a degenerative disease manifesting a combination of parkinsonism, cerebellar, pyramidal, and autonomic (including urinary, sexual and anorectal) dysfunction. It is pathomorphologically defined, but lacks a definitive clinical diagnostic test. In patients with probable MSA, abnormal sphincter EMG, as compared to control subjects, has been found in the majority of patients in all the different forms of the disease in most studies, including patients who, as yet, have no urological or anorectal problems. Patients with Parkinson’s disease (PD) as a rule do not show marked sphincter EMG abnormalities in the first five years of the disease. Thus, abnormal spontaneous activity or marked motor unit potential changes in sphincter muscles are helpful in distinguishing MSA from PD in the first five years after the onset of symptoms and signs, and from pure autonomic failure, as well as from cerebellar ataxias, if other causes for sphincter denervation have been ruled out. EMG does not distinguish MSA from progressive supranuclear palsy. How early in the course of MSA these abnormalities become significant enough to support diagnosis remains to be established by prospective studies.     

Disturbances of micturition in patients with a spinal arteriovenous malformation

Neuro-urological studies were performed on 9 patients with a spinal arteriovenous malformation (S-AVM). The micturitional history revealed that all 9 patients had voiding symptoms, obstructive in 9 and irritative in 3 patients. All patients still had obstructive symptoms after treatment of S-AVM. Six of the 9 patients had a large volume of residual urine before treatment; 5 showed urinary retention. Four of the 5 patients (80%) for whom urodynamic studies were performed before treatment had micturitional dysfunction; 2 patients had detrusor hyperreflexia, 1 with detrusor external urethral sphincter dyssynergia (DSD) and 1 with a normal sphincter, 1 patient had an autonomous bladder with DSD and 1 patient had an atonic bladder with DSD. Only 1 patient had a normal bladder and sphincter. Findings of the urodynamic studies after treatment in 9 patients showed detrusor hyperreflexia in 3 patients (2 with DSD and 1 with normal sphincter), autonomous bladder in 1 patient with DSD, atonic bladder in 4 patients (2 with DSD, 1 with incompetent sphincter and 1 with normal sphincter) and normal bladder with normal sphincter in 1 patient. Lower urinary function after treatment of S-AVM was improved in 2 patients, unchanged in 4 patients and worsened in 3 patients. The above results showed 80% of S-AVM had a severe neuropathic bladder manifested mainly by disturbance of micturition. Treatment of S-AVM does not necessarily improve the lower urinary tract function.     

Sphincter EMG and differential diagnosis of multiple system atrophy.

Multiple system atrophy (MSA) is a degenerative disease manifesting a combination of parkinsonism, cerebellar, pyramidal, and autonomic (including urinary, sexual, and anorectal) dysfunction. It is pathomorphologically defined, but lacks a definitive clinical diagnostic test. Sphincter electromyography (EMG), reflecting Onuf's nucleus degeneration, has been proposed as a helpful test; its value has been reevaluated by a critical review of the literature. In patients with probable MSA, abnormal sphincter EMG, as compared to control subjects, has been found in the majority of patients in all the different forms of the disease in most studies, including patients who, as yet, have no urological or anorectal problems. The prevalence of abnormalities in the early stages of MSA is as yet unclear. Patients with Parkinson's disease (PD) as a rule do not show severe sphincter EMG abnormalities in the early stage of the disease. Anal sphincter EMG abnormalities (abnormal spontaneous activity or motor unit potential changes three standard deviations above valid control data) distinguish MSA from PD in the first 5 years after the onset of symptoms and signs, and from pure autonomic failure, as well as from cerebellar ataxias, if other causes for sphincter denervation have been ruled out. With such criteria, the sensitivity of the method is, however, low. EMG does not distinguish MSA from progressive supranuclear palsy. Future studies should use standardized anal sphincter EMG to better compare results from different centers and precisely define the sensitivity and specificity of the method.     

Botulinum toxin therapy: its use for neurological disorders of the autonomic nervous system

Botulinum toxin (BoNT) has gained widespread use for the treatment of overactive muscles, overactive exocrine glands and, most recently, non-muscular pain conditions. Autonomic conditions treated with BoNT include achalasia, gastroparesis, sphincter of Oddi spasms, and unspecific esophageal spasms in gastroenterology and prostate disorders in urology. BoNT’s use for autonomic conditions related to neurology includes various forms of bladder dysfunction (detrusor sphincter dyssynergia, idiopathic detrusor overactivity, neurogenic detrusor overactivity, urinary retention and bladder pain syndrome), pelvic floor disorders (pelvic floor spasms and anal fissures), hyperhidrosis (axillary, palmar, and plantar hyperhidrosis, diffuse sweating, Frey’s syndrome) and hypersalivation (hypersalivation in Parkinsonian syndromes, motor neuron disease, neuroleptic use, and cerebral palsy). Hyperhidrosis, hypersalivation, some forms of bladder dysfunction and pelvic floor disorders can easily be treated by neurologists. Most bladder dysfunctions require cooperation with urology departments.     

The value of external anal sphincter electromyography for the diagnosis of multiple system atrophy.

OBJECTIVE: To assess the value of external anal sphincter electromyography (ASEMG) for the diagnosis of multiple system atrophy (MSA) among various causes of parkinsonism. ASEMG denervation profiles have previously been proposed as a diagnosis test for MSA, but their specificity is disputed. METHODS: ASEMG variables of 52 parkinsonian patients were analyzed according to the clinical diagnosis: MSA (n = 31) or no MSA (n = 21). Mean motor unit potential duration, percentage of polyphasicity, and the electromyographer's interpretation were analyzed according to clinical diagnosis, disease duration, genitourinary symptoms, gender, parity, and history of pelvic surgery. RESULTS: All patients with MSA showed ASEMG denervation. Mean motor unit potential duration was the most discriminant variable. No patient with MSA had a mean duration less than 12 ms and no patient without MSA had one greater than 16 ms. ASEMG discriminates between patients with MSA and Parkinson's disease. Using a threshold of 13 ms, the sensitivity was 80% and specificity was almost 70% (positive predictive value, 80%) for the diagnosis of MSA. Age, history of pelvic surgery, and to a lesser extent, female gender, parity, disease duration, and presence of urinary symptoms increased the likelihood of abnormal ASEMG. CONCLUSION: ASEMG was highly sensitive and rather specific for the diagnosis of MSA.     

Neurourodynamic evaluation of voiding dysfunction in multiple sclerosis

During a period of 2 1/2 years, 198 patients with definite MS were admitted to our neurological department. 88 were investigated neurourodynamically because of distinct voiding dysfunction. 73 patients showed detrusor hyperreflexia, 14 detrusor hyporeflexia or areflexia and one had normal findings. There was no obvious correlation between the occurrence of the symptoms, irritative and obstructive, and the allocation of the patients into different cystometric groups. The predominant symptom was urge incontinence. More men had been treated or were permanently treated with intravesical catheter, but mean residual urine did not show any sex difference. In 36 patients with detrusor hyperreflexia, dyssynergia was observed and was classified into 3 groups. In the group with clonic sphincter EMG activity during voiding, 5 of the patients had dyssynergia because of flexor spasms transmitted to the sphincter. In patients with dyssynergia characterized by increased sphincter activity throughout detrusor contraction, a large mean residual urine was noted, but dyssynergia did not always prevent acceptable emptying. A low rate of complication in the upper urinary tract was observed. Treatment is discussed.     

Bladder dysfunction in acute transverse myelitis: magnetic resonance imaging and neurophysiological and urodynamic correlations

AIMS: To evaluate micturition abnormalities in acute transverse myelitis and correlate these with evoked potentials, magnetic resonance imaging (MRI), and urodynamic findings. SETTING: Tertiary care teaching hospital. PATIENTS: 18 patients with acute transverse myelitis, aged 4-50 years; 15 had paraparesis and three quadriparesis. METHODS: Patients with acute transverse myelitis had a neurological evaluation and tibial somatosensory and motor evoked potential studies in the lower limbs. Spinal MRI was carried out using a 1.5 T scanner. Urodynamic studies were done using Dantec UD 5500 equipment. Neurological outcome was determined on the basis of Barthel index score at six months as poor, partial, or complete. In some patients, urodynamic studies were repeated at six and 12 months. RESULTS: Spinal MRI in 14 of the 18 patients revealed T2 hyperintense signal changes extending for at least three spinal segments in 13; one patient had normal MRI. In the acute stage, 17 patients had a history of urinary retention and one had urge incontinence. On follow up at six months two patients regained normal voiding, retention persisted in six, and storage symptoms developed in 10, of whom five also had emptying difficulties. Urodynamic studies showed an areflexic or hypocontractile bladder in 10, detrusor hyperreflexia with poor compliance in two, and detrusor sphincter dyssynergia in three. Early abnormal urodynamic findings commonly persisted at the six and 12 months examinations. Persistent abnormalities included detrusor hyperreflexia, dyssynergia, and areflexic bladder. The urodynamic abnormalities correlated with muscle tone and reflex changes but not with sensory or motor evoked potentials, muscle power, MRI signal changes, sensory level, or six months outcome. CONCLUSIONS: Bladder dysfunction is common in acute transverse myelitis and may be the only sequel. Urodynamic study is helpful in evaluating the bladder dysfunction and also in its management.     

Quantitative electromyography of the external anal sphincter in Parkinson's disease and multiple system atrophy

The distinction of multiple system atrophy (MSA) from Parkinson's disease (PD) can be difficult, especially early in the disease. In MSA degeneration of sacral anterior horn cells (Onuf's nucleus) results in denervation-reinnervation of anal and urethral sphincter muscles, which can be recognized as neurogenic electromyographic (EMG) changes of motor unit potentials. Sphincter EMG has therefore been recommended as a test for distinguishing MSA from PD. Our results confirm the presence of marked neurogenic EMG changes of the external anal sphincter muscle in patients with probable MSA compared to healthy controls. However, in patients with probable PD, our quantitative EMG data show a scatter from normal to marked neurogenic changes and the degree of EMG abnormality is correlated to the duration of the disease. Thus an abnormal sphincter EMG cannot be taken as a strong indicator of MSA rather than PD in the individual patient, especially in long-standing cases.     

Modulation of the bulbocavernosus reflex during voiding: loss of inhibition in upper motor neuron lesions

The bulbocavernosus reflex (BCR) is a sacral segmental reflex which is suppressed throughout most of micturition. The BCR was evaluated by recording the associated EMG activity using a concentric needle electrode placed in the external urethral sphincter. The influence of the central nervous system (CNS) on the BCR was studied in 29 neurologically normal individuals and in 33 patients with upper motor neuron (UMN) lesions and voiding dysfunction. Ninety percent (26/29) of the neurologically normal patients did not have a BCR during most of micturition. By comparison, all the patients with an UMN lesion had a positive BCR beginning early during voiding. The finding of suprasegmental modulation of the BCR during voiding demonstrated by external urethral sphincter EMG was a more sensitive although slightly less specific sign of UMN bladder dysfunction than detrusor sphincter dyssynergia; uninhibited bladder contractions were neither sensitive nor specific for UMN lesions.     

Transcranial brain sonography findings in discriminating between parkinsonism and idiopathic Parkinson disease

BACKGROUND: In several pilot studies, transcranial brain sonography findings of substantia nigra and lenticular nucleus discriminated between idiopathic Parkinson disease (PD) and atypical parkinsonian disorders. OBJECTIVE: To study the use of transcranial brain sonography in excluding the diagnosis of idiopathic PD in patients with sporadic parkinsonism. DESIGN AND SETTING: All patients with parkinsonism admitted to our movement disorder clinic from January 1, 2003, through December 31, 2005, who fulfilled clinical diagnostic criteria for definite PD, probable parkinsonian variant of multiple-system atrophy (MSA-P), or probable progressive supranuclear palsy (PSP) were prospectively studied with transcranial brain sonography by an investigator blinded to clinical diagnoses. Patients Eligible patients included 138 with sporadic idiopathic PD (82 men and 56 women; mean +/- SD age, 67.1 +/- 9.8 years; mean +/- SD disease duration, 7.5 +/- 6.3 years; mean +/- SD motor score on the Unified Parkinson Disease Rating Scale, 32.6 +/- 18.1), 21 with MSA-P (10 men and 11 women; mean +/- SD age, 65.4 +/- 9.5 years; mean +/- SD duration of disease, 3.1 +/- 2.0 years; mean +/- SD motor score, 33.5 +/- 16.1), and 22 with PSP (13 men and 9 women; mean +/- SD age, 71.2 +/- 5.5 years; mean +/- SD duration of disease, 3.4 +/- 2.4 years; mean +/- SD motor score, 46.2 +/- 18.9). In 7 patients, transcranial brain sonography was not possible owing to insufficient temporal acoustic bone windows. MAIN OUTCOME MEASURES: Sensitivity, specificity, and predictive value of transcranial brain sonography in indicating an atypical parkinsonian syndrome rather than idiopathic PD in patients with sporadic parkinsonism. RESULTS: Normal echogenic substantia nigra indicated MSA-P rather than PD (sensitivity, 90%; specificity, 98%; positive predictive value, 86%), whereas third-ventricle dilatation of more than 10 mm in combination with lenticular nucleus hyperechogenicity indicated PSP rather than PD (sensitivity, 84%; specificity, 98%; positive predictive value, 89%). Normal echogenic substantia nigra combined with lenticular nucleus hyperechogenicity indicated MSA-P or PSP (sensitivity, 59%; specificity, 100%; positive predictive value, 100%). In parkinsonism with age at onset younger than 60 years, normal echogenic substantia nigra alone indicated MSA-P or PSP (sensitivity, 75%; specificity, 100%; positive predictive value, 100%). CONCLUSIONS: Distinct transcranial brain sonography findings can exclude the diagnosis of PD in patients with sporadic parkinsonism. Sonographic discrimination of atypical parkinsonian syndromes from PD is clearer in patients with onset of parkinsonism at younger than 60 years.     

Urinary dysfunction and orthostatic hypotension in multiple system atrophy: which is the more common and earlier manifestation?

OBJECTIVES: Urinary dysfunction and orthostatic hypotension are the prominent autonomic features in multiple system atrophy (MSA). A detailed questionnaire was given and autonomic function tests were performed in 121 patients with MSA concerning both urinary and cardiovascular systems. METHODS: Replies to the questionnaire on autonomic symptoms were obtained from 121 patients including three clinical variants; olivopontocerebellar atrophy (OPCA) type in 48, striatonigral degeneration (SND) type in 17, and Shy-Drager type in 56. Urodynamic studies comprised measurement of postmicturition residuals, EMG cystometry, and bethanechol injection. Cardiovascular tests included head up tilt test, measurement of supine plasma noradrenaline (norepinephrine,NA), measurement of R-R variability (CV R-R), and intravenous infusions of NA and isoproterenol. RESULTS: Urinary symptoms (96%) were found to be more common than orthostatic symptoms (43%) (p<0.01) in patients with MSA, particularly with OPCA (p<0.01) and SND (p<0.01) types. In 53 patients with both urinary and orthostatic symptoms, patients who had urinary symptoms first (48%) were more common than those who had orthostatic symptoms first (29%), and there were patients who developed both symptoms simultaneously (23%). Post-micturition residuals were noted in 74% of the patients. EMG cystometry showed detrusor hyperreflexia in 56%, low compliance in 31%, atonic curve in 5%, detrusor-sphincter dyssynergia in 45%, and neurogenic sphincter EMG in 74%. The cystometric curve tended to change from hyperreflexia to low compliance, then atonic curve in repeated tests. Bethanechol injection showed denervation supersensitivity of the bladder in 19%. Cardiovascular tests showed orthostatic hypotension below -30 mm Hg in 41%, low CV R-R below 1.5 in 57%, supine plasma NA below 100 pg/ml in 28%, and denervation supersensitivity of the vessels (alpha in 73%; beta2 in 60%) and of the heart (beta1 in 62%). CONCLUSION: It is likely that urinary dysfunction is more common and often an earlier manifestation than orthostatic hypotension in patients with MSA, although subclinical cardiovascular abnormalities appear in the early stage of the disease. The responsible sites seem to be central and peripheral for both dysfunctions.     

Anal sphincter EMG in the diagnosis of parkinsonian syndromes

Winge K, Jennum P, Lokkegaard A, Werdelin L. Anal sphincter EMG in the diagnosis of parkinsonian syndromes.
Acta Neurol Scand: 2010: 121: 198–203.
© 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Background – The role of electromyography (EMG) recorded from the external anal sphincter (EAS) in the diagnosis of atypical parkinsonian syndromes is a matter for continuous debate. Most studies addressing this issue are retrospective. Methods – In this study, we prospectively investigated six patients with Parkinson’s Disease (IPD), 14 patients with multiple system atrophy (MSA) and eight with progressive supranuclear palsy (PSP) using EMG of the EAS, motor‐evoked potential (MEP) to the EAS and EMG of m. gastrocnemius and nerve conduction velocity measured at the sural nerve. Patients were followed up for 2 years to secure correct diagnosis. Results – The mean duration of motor unit potentials (MUPs) recorded from the EAS was significantly longer in patients with MSA and PSP compared with MUPs recorded from patients with PD (P < 0.005 for both). There were no signs of diffuse loss of motor neurons or peripheral neuropathy. MEP revealed signs of supranuclear affection in patients with MSA, whereas in patients with PSP the mechanism is a focal loss of motor neurons in Onuf’s nucleus. Conclusion – Abnormal EMG of the EAS is strongly suggestive of atypical parkinsonism and the pathophysiology may be different in patients with MSA and PSP.     

Sonographic assessment of urinary retention in multiple system atrophy and idiopathic Parkinson's disease.

Sonography of the bladder was performed before and after voluntary voiding in 20 subjects with possible/probable multiple system atrophy (MSA), 20 patients with idiopathic Parkinson's disease (PD), and 20 healthy controls. Mean residual volume was 173 ml (SD, 194) in MSA and significantly increased compared to both PD (21 ml; SD, 49) and controls (13 ml; SD, 12). Incomplete voiding (>100 ml of residual volume) was found in 11 subjects with MSA but only in 1 patient with PD. Positive predictive value of increased residual volume for MSA was 91.6% in this study, whereas negative predictive value was only 67.8. Bladder sonography is an objective, simple, and safe tool that allows one to screen for urinary retention, which is highly suggestive but incompletely sensitive for MSA. Because sonography is easily accessible and rapidly performed, it is feasible for routine assessment of atypical Parkinsonism.