PubMed Health⌕ Search

Biomedical subjects

David B Vodusek

Publications and source records attributed to David B Vodusek.

13 recordsLinked to original sources
PubMed2006

Electromyography of pelvic floor muscles.

Pelvic floor muscles (PFM) are intimately involved in function of lower urinary tract, the anorectum and sexual functions, therefore their neural control transcends the primarily important somatic innervation of striated muscle, as they are directly involved in "visceral activity". Neural control of pelvic organs is affected by a unique co-ordination of somatic and autonomic motor nervous systems. Visceral and somatic sensory fibres supply sensory information from pelvic organs; their input influences through central integrative mechanisms also pelvic floor muscle activity. Anatomically, somatic afferent and efferent nerves of the sacral cord segments, reflexly integrated at the spinal cord and brainstem level, conduct neural control of PFM. The inputs from several higher centres influence the complex reflex control and are decisive for voluntary control, and for socially adapted behaviour related to excretory functions.

Autonomic Nervous System↗
PubMed2006

Bladder dysfunction in patients with cauda equina lesions.

AIMS: Data on lower urinary tract (LUT) function obtained in larger, systematically studied populations of patients with cauda equina lesions are limited. We report urinary function in 65 patients with chronic lesions. METHODS: A urinary function questionnaire was used, and neurological examination, quantitative electromyography (EMG) of the external anal sphincter (EAS) muscles, EMG assessment of the sacral reflex, and conventional urodynamic measurements were performed. RESULTS: Severe LUT dysfunction was found in 14%/15%, moderate in 27%/46%, and mild in 46%/39% men/women. Urinary symptoms interfered with daily life in 88%/92% and sexual life in 72%/67% of sexually active men/women. Symptoms of disturbed bladder emptying were the most common (95%/92% men/women), followed by urinary incontinence (56%/71%) and symptoms of overactive bladder (40%/56%). Perianal sensation was abnormal in 96%, EMG of the EAS muscle in 88%, and sacral reflex in 84% of patients. In 40%/17% men/women, a postvoid residual (>100 ml) was found. On filling cystometry overactive bladder was found in 21%/0%, reduced detrusor capacity in 9%/15%, and during voiding phase an acontractile detrusor or detrusor underactivity were found in 59%/85% men/women. Using multiple linear regression analysis, perianal sensory loss (P=0.0001) and female gender (P<0.02) had a significant positive effect on urinary incontinence score. CONCLUSIONS: Our study demonstrated significant LUT dysfunction, which disturbed the life of the majority of patients with chronic lesions of the cauda equina. Due to poor correlation between patients' symptoms and urodynamic findings cystometric surveillance is proposed in all patients with significant cauda equina lesions.

Adult↗
PubMed2005

Event-related potentials elicited by distractors in an auditory oddball paradigm in schizophrenia.

Patients with schizophrenia are affected more adversely than healthy controls by distracting conditions, due to their inability to adequately apportion attentional resources to targets or distractors. We attempted to re-evaluate the effects of distractors in 25 patients with chronic schizophrenia and in 12 controls. They performed an auditory target-detection task with 1500 Hz tone distractors and an additional control condition where a 1500-Hz tone was used as the target. The rate of target misses for patients with schizophrenia was 3.79% in non-distractor conditions and 14.79% in distractor conditions. Significantly reduced N100 responses to distractors and distractor condition targets were found. P300 responses to all target stimulus categories were reduced, but P300 responses to distractors were equal to those in the control group. There was a reduction of P300 amplitudes to distractors in both groups; however, only the control group showed significant enlargement of P300 amplitude when the distractors became the target stimuli. There is evidence that patients with schizophrenia tend to be less able to allocate their attentional resources adequately to target vs. distractor stimuli. When the distractors became the target stimuli, their responses remained unchanged, which suggests their inability to appropriately integrate stimulus information with contextual information.

Acoustic Stimulation↗
PubMed2004

Anatomy and neurocontrol of the pelvic floor.

Neural control of pelvic organs is affected by a unique coordination of somatic and autonomic motor nervous systems. Sensory information and feedback is supplied by both visceral and somatic sensory fibers. The anatomical features of the pelvic floor and perineal muscles, and their innervation are described. Altogether more detailed information is known in humans on the peripheral innervation as compared to the central nervous system centers and connections of pelvic organ neurocontrol. Controversies in regional neuroanatomy are explained. Reports on individual variability and asymmetry - the former particularly with methods revealing structures, and the latter with functional methods - are interesting but need further validation.

Afferent Pathways↗
PubMed2002

Comparison of quantitative techniques in anal sphincter electromyography.

Data comparing results and utility of different quantitative electromyographic (EMG) techniques are limited. In the present study, we analyzed the EMG signal from the external anal sphincter (EAS) muscle using three techniques of motor unit potential (MUP) analysis, and a technique of interference pattern (IP) analysis. We examined 56 patients with damage to the cauda equina or conus medullaris, and 64 control subjects. Using manual-MUP and multi-MUP analysis about 20 MUPs, using a single-MUP technique about 10 MUPs, and using turn/amplitude (T/A) analysis about 20 IP samples were obtained. The sensitivities of these techniques in distinguishing neuropathic from control muscles were calculated. The single-MUP technique detected 63%, manual-MUP 57%, and multi-MUP analysis 62% of neuropathic muscles, and MUP parameters obtained by each of these differed significantly from the other. The sensitivity of T/A analysis of IP was 29%. Our results confirm the need for separate MUP normative data for each of the MUP analysis techniques, and favor them over the IP analysis technique. The normative data presented for the EAS muscle should improve and promote quantitative EMG in patients.

Adult↗
PubMed2002

Standardization of anal sphincter electromyography: quantification of continuous activity during relaxation.

AIM: Sphincter motor units (MUs) are continuously firing during relaxation. The quantification of this activity is a potentially useful electromyographic (EMG) parameter related to the number of MUs innervating the muscle and the level of motor neuron excitation. The aim of the present study was to develop a reliable, quantitative measure of continuous sphincter muscle activity during relaxation. METHODS: EMG activity was analyzed during relaxation, 1 minute after insertion of the concentric needle electrode into four sites in the external anal sphincter (EAS) muscle. In 10 control subjects, 8 interference pattern samples were obtained by "turn/amplitude" analysis. In 35 control subjects, a multi-MUP count of continuously firing motor unit potentials (MUPs) was used, quadruplets with scores of 0-6 obtained, and the lower reference limits (95th percentile) calculated. This approach was then evaluated in 57 patients (182 muscles) with cauda equina or conus medullaris lesion (CECML) and 7 patients (13 muscles) with "idiopathic fecal incontinence." RESULTS: The lower reference ("outlier") limits for MUP count were 0 0 6 6 and 0 1 2 2 for the subcutaneous, and 0 0 0 6 and 0 0 1 1 for the deeper EAS muscles. Both patient groups had a significantly diminished number of continuously firing MUPs, which was below the reference range in 43% of the EAS muscles from CECM patients and in 85% of muscles from patients with idiopathic fecal incontinence. In patients with CECML, the decrease in MUP count correlated with the severity of the lesion, as defined by the sensory deficit. CONCLUSIONS: MUP count in sphincter muscles during relaxation is technically feasible, and it is a promising tool, particularly in patients with idiopathic fecal incontinence.

Adult↗
PubMed2002

The role of electrophysiology in the evaluation of incontinence and prolapse.

PURPOSE OF REVIEW: Apart from histopathology, electrophysiological methods are the only tests to reveal neuromuscular involvement in the absence of gross anatomical lesions. They have played a major role in establishing the neuromuscular lesion due to vaginal delivery as a risk factor for incontinence and pelvic organ prolapse, but there is no consensus on the usefulness of different methods. It is timely to reevaluate their validity, and their role in urogynecology. RECENT FINDINGS: The most important development is the move towards standardization of the diagnostic approach, based on computer assisted quantified techniques of concentric needle electromyography. Studies using less operator biased techniques have confirmed subtle pelvic floor muscle changes in parous women. Reports on usefulness of different tests as predictors of treatment outcome are controversial. SUMMARY: Standardization of concentric needle electromyography strengthened the position of this test as practical and informative. Neuromuscular changes following vaginal delivery have been reconfirmed, but the usefulness of particular electrophysiological tests in the individual patient needs to be further researched. Valid clinical neurophysiological methods remain valuable as research tools for incontinence and prolapse pathophysiology.

Electromyography↗
PubMed2002

The importance of HLA DQB1*0602 typing in Slovene patients with narcolepsy.

The HLA class II region genes DQB1*0602 and DQA1*0102 are currently the best genetic predictors for narcolepsy in humans (1(. The aim of this study was to identify the HLA DQ alleles (DQB1*0602 and DQA1*0102) in Slovene sporadic narcoleptic patients. 11 patients who fulfilled ICSD criteria for narcolepsy entered the study. DRB1*1501 DQB1*0602 was present in all the patients while DQA1*0102 was absent in 2 patients. We propose that DQB1*0602 typing is important in diagnosing narcolepsy in Slovene patients

HLA-DQ Antigens↗
PubMed2002

Mictunrition and the sacral reflex arc: lessons from electrophysiological techniques.

Electrophysiological techniques applied either for diagnostic or therapeutic reasons have contributed to elucidation of the neurocontrol of micturition. But the ability of electrophysiological diagnostic tests to reveal neurogenic involvement in patients suffering from lower urinary tract dysfunction is limited, and has been overestimated. Furthermore, the correlation between a proven neurogenic deficit and the consecutive dysfunction is complex. The electrophysiological tests, however, may also be applied for testing the central nervous system integrative function, such as in testing reflex thresholds, excitability levels of motor nuclei, etc. The use of electrical stimulation for therapeutic purposes has instigated much physiological research. Insights related to micturition neurocontrol, as for instance that afferent inputs from lumbosacral and vesical sensory fibres modulate the micturition threshold, are being therapeutically exploited. It is expected that further use of electrophysiological techniques, being complementary to functional neuroimaging, will clarify particularly the temporal aspects of neurocontrol mechanisms involved in micturition.

Electric Stimulation↗