- Email: [email protected]
autonomic disorders
S76
Oral Presentations: Workshops
to promote functional recovery of function following stroke and spinal cord injury. It is therefore somewhat surprising that the spinal cord is often not mentioned in relation to motor disorders. The spinal cord receives substantial dopaminergic innervation, which is essential for initiation of gait at least in animals. Could it be that pathological changes in this innervation is involved in the gait disturbance of Parkinson patients? Or in Restless Leg Syndrome? Several studies have documented altered transmission in spinal networks in patients with various motor disorders decades ago, but such findings appear not to have received much attention. Maybe it is time that we start minding the spinal cord and consider the role that it in all likelihood plays in movement disorders.
WS2-4 Inappropriate modulation of antagonistic inhibition at onset of voluntary contraction in Parkinson’s disease
WS2-2 Spinal interneurones R. Katz1 , V. Marchand1 Er 6 UPMC Med Phys & Readapt
1
Disynaptic Ia reciprocal inhibition from the peroneal nerve afferents to the soleus muscle was significantly increased after TES. On the other hand, the disynaptic Ia inhibition of the TA muscle by group Ia volleys from the tibial nerve was decreased in all subjects of 3 patients in whom H reflexes were detected in the TA muscle. TES might change transmission efficiency of two synapses originated from disynaptic Ia inhibitory interneurons of the TA muscle. We suggest that the facilitation of voluntary contraction in the agonist muscle and the reduction of the spasticity in the antagonist muscle by TES might result from enhancement of the synaptic transmission efficiency.
La Salpetriere hospital, France
Motor function (muscle tone, maintenance of posture and movement) is finally expressed by muscle contractions depending on the activity of motoneurones, the final common pathway, of motor activity. Characteristics of motoneurone discharge (number of motoneurones firing, their frequency of discharge and pattern of activation) is the reflect of an integration of activity in the different structures of the central nervous system (motor cortex, cerebellum, basal ganglia, vestibular system, spinal interneurones). Most of the data available concerning the knowledge of spinal interneurones involved in motor control have been drawn in experiments performed in reduced animal preparations. The introduction in the fiftees of intracellular recordings has allowed Eccles, Lundberg and their colleagues to describe the synaptic connections of spinal interneurones. However, it is obvious that such invasive methods cannot be used in humans but data obtained in animals cannot be transposed in humans without caution taking into account the phylogenetic evolution with the appearance of bipedal stance and gait. A pre-requisite to investigate spinal interneurones is the development of non-invasive methods unabling to investigate selectively these pathways in humans. These methods allow to study among others recurrent inhibition Ia and Ib inhibition, presynaptic Ia inhibition and homosynaptic depression, propriospinal pathways, monosynaptic Ia excitation, excitation by group II afferents or cutaneous muscle responses. Experiments performed during maintenance of posture, locomotion and voluntary movement in healthy subjects have allowed to reveal specific changes in the excitability of spinal interneurones linked to a given motor task. In central nervous system lesioned patients, they have brought arguments about the pathophysiology of muscle tone abnormalities and motor control disorders. TMS and tDCS applied to the motor cortex allow to induce non-invasive and reversible plasticity at cerebral and spinal levels. WS2-3 Disynaptic Ia reciprocal inhibition in stroke patients before and after therapeutic electrical stimulation Y. Masakado1 , Y. Muraoka2 , T. Ohta3 , Y. Tomita4 , A. Kimura3 1 Department of Rehabilitation Medicine, Tokai University School of Medicine, Kanagawa, Japan, 2 National Murayama Hospital, Japan, 3 Keio University Tsukigase Rehabilitation Center, Japan, 4 Department of Biosciences and Informatics, The Faculty of Science and Technology, Keio University, Japan Therapeutic effects of transcutaneous electrical stimulation (TES), such as reduction of spasticity and improvements in motor control, have often been observed. The purpose of this study is to evaluate the efficacy of TES on hemiplegic patients from the viewpoint of voluntary movement in paretic lower extremity and reciprocal Ia inhibition. The stimulation parameters were held at fixed values as follows: frequency at 20 Hz, monophasic rectangular waveform, pulse width at 0.3 ms, and mild contraction intensity. A 5-second stimulation followed by 15-second rest was repeated for 15 min. After TES, the surface EMG showed a reduction in co-contraction and change to reciprocated movements of quadriceps and hamstrings. These findings suggest improvements in voluntary movements of knee joints, though TES was applied on paretic lower leg. We also studied disynaptic Ia reciprocal inhibition between the soleus muscle and the tibialis anterior (TA) muscle before and after TES to the TA muscle. The amount of disynaptic Ia reciprocal inhibition was determined by the short latency suppression of the soleus or TA muscle H reflexes by conditioning stimulation of the antagonistic muscle nerves.
H. Morita1 1 Department of Medicine (Neurology & Rheumatology), Shinshu University, Matsumoto, Japan Spinal reflex activity in Parkinson’s disease (PD) have been studied at rest and during voluntary movement. Although reflex activities at rest have examined for many reflex pathways such as reciprocal Ia inhibition, heteronymous Ib inhibition, recurrent inhibition, and presynaptic inhibition, results are still controversial among studies. This may be due to deference of severity, effect of medication or age among studies. On the other hand, abnormal modulation of spinal reflex activity with voluntary movement, especially at onset of contraction, was common among studies. In normal subject, there is a clear reciprocal control that modulated supraspinaly at onset of contraction. When a subject performs dorsiflexion, the extent of reciprocal inhibition increases as a central modulation to inhibit motoneuronal activity of antagonists. During plantarflexion the reciprocal inhibition contrary decreases in normal subjects. Modulation of the inhibition with voluntary contraction was completely opposite to normal subjects. At onset of wrist flexion there was no modulation of reciprocal inhibition form extensors to flexor carpi radialis in PD, which should decrease in normal subjects. At onset of ankle dorsiflexion there was no reciprocal inhibition from tibialis anterior to soleus but was paradoxical facilitation in PD. Such paradoxical phenomenon was also observed with TMS induced facilitation to soleus H-reflex. In normal subjects, TMS facilitates soleus H-reflex at onset of plantarflexion. However, TMS inhibit soleus H-reflex at onset of plantarflexion. The latency of this inhibitory activity was a little longer than facilitation. Treatment of PD with medication or surgery improved some part of these abnormalities. These observations indicated that inappropriate supraspinal modulation of reciprocal control at onset of voluntary contraction related to motor symptoms of PD such as freezing phenomenon, although responsible descending pathway are still controversial. WS3. Neurophysiology of urination and pelvic floor muscles WS3-1 Sphincter physiology: with reference to neurologic/autonomic disorders R. Sakakibara1 1 Neurology, Internal Medicine, Sakura Medical Center, Toho University, Japan Anal and urethral sphincters participate actively in regulating bladder, bowel, and sexual function, with the former two being predominant. Anal and urethral sphincters are thought to share innervation. Internal sphincter is innervated by sympathetic noradrenergic fibers that originate from T12-L2 intermediolateral cell columns, whereas external sphincter is innervated by somatic fibers that originate from S2 3 anterior horn cells in the Onuf’s nucleus. Spinal sphincter descending fibers have not fully been determined in humans, but probably lie in the lateral columns. Anatomical and functional imaging studies suggest that brain structures relevant to the sphincter and the pelvic floor include area 4, supplementary motor area, frontal cortex, cerebellum, and basal ganglia. If one of these structures is affected in neurologic/autonomic disorders, sphincter function may alter. One particular example is multiple system atrophy (MSA), where a various combination of parkinsonian, cerebellar, and autonomic (including cardiovascular, urinary, and anorectal) dysfunction may occur. In MSA internal and external sphincter denervation occurs, which appears as open bladder neck at the start of bladder filling (internal) and neurogenic
29th International Congress of Clinical Neurophysiology changes in motor unit potential analysis of sphincter electromyography (EMG) (external). Since involvement of the sacral Onuf’s nucleus is extremely uncommon in idiopathic Parkinson’s disease (iPD), sphincter EMG can become a practical method to distinguish MSA from iPD. If sphincter does not relax properly on evacuation, it shows obstructed pattern in the urodynamic pressure-flow analysis. Detrusor (bladder)external sphincter dyssynergia is such a condition that originates from higher malfunction in MSA. Only recently, peripheral nerve lesion, e.g., e syndrome, is shown to cause detrusor-internal sphincter Guillain Barr´ dyssynergia, due probably to increased peripheral nerve firing and ephaptic transmission. We need to treat the sphincter properly in order to maximize the quality of life in patients and to avoid urinary complications. WS3-2 Neurophysiology of pelvic floor A. Tello1 1 Clinical Neurophysiology Department. Hospital Espanol de Mexico, Mexico Pelvic floor disorders affect one in four adult women of all ages. The etiology of these disorders is multifactorial and results from a combination of risk factors. The clinical picture varies and can be presented as pelvic organ prolapse, fecal or urinary incontinence and sexual dysfunction. With a comprehensive neurological history and physical examination, the clinician might suggest the diagnosis as to where or which of the control mechanism is affected. However, most times, it is difficult to draw a conclusion on clinical grounds only, as normal pelvic floor function involves several neural paths, both peripheral and central controllers, and somatic and autonomic nervous systems. Given the complexity of the system, it is recommended to perform, in addition to anatomic studies, electrodiagnostic tests, designed to investigate pelvic floor dysfunction of neural controllers. A number of tests are performed to evaluate pelvic floor muscles and external anal sphincter, including pudendal nerve conduction studies, sacral reflexes, somatosensory evoked potentials and motor evoked potentials. When lower motor neuron lesion is suspected, EMG of anal and urethral sphincters is the most appropriate test, since information about denervation/reinnervation can be drawn from this method. If the lesion is at the level of the sacral level, besides EMG examination, sacral reflexes give important information. Pudendal nerve terminal motor latencies (PNTMLs), examines conduction of nerve fibers rather than levels of innervation, and examine large myelinated fibers conduction rather than that of the unmyelinated fibers which enclose the autonomic innervation. In cases of upper motor neuron dysfunction, the utility of SEPs and MEPs is less clear. This discussion reviews the clinical usefulness, the strengths and pitfalls of each technique, in establishing the integrity of the peripheral innervation of the pelvic floor and how the combination of different methods help to determine the level of the lesion. WS3-3 Clinical study
neurophysiological tests in uroneurology
1
D.B. Vodusek Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
1
Neurophysiological tests are used in clinical practice for assessment of individual patients with uroanogenital disorders or pelvic pain to diagnose nervous system lesions, and to define dysfunction. Needle EMG and conduction studies (particularly bulbocavernosus reflex) are useful in diagnosing lesions within the lower (S2-S4) sacral reflex arcs, and are more sensitive (whereas SEPs are less sensitive) than clinical examination to detect abnormality. Sympathetic skin response recording is still mostly a research tool. Kinesiological sphincter EMG recordings demonstrate detrusor/sphincter, and bowel/sphincter discoordination in patients with CNS lesions. Application of sphincter EMG has revealed myogenic urethral sphincter hyperactivity as cause for urinary retention in women, thus defining a new clinical syndrome (Fowler syndrome). Neurophysiological methods have demonstrated the (partly) neuropathic cause of “genuine” stress urinary and anal incontinence. In conclusion, neurophysiological tests remain interesting for clinical research in patients with uroanogenital dysfunction. EMG with sacral reflex recording is diagnostic in patients with suspected conus, cauda equina, sacral root, pudendal and levator ani nerve involvement, and defines lower motor neuron and reflex arc lesions due to trauma, compression, inflammation and dysraphism.
S77 WS3-4 Human cremaster muscle (CM) and cremasteric reflex (CMR) C. Ertekin1 Department of Neurology and Clinical Neurophysiology, Ege University, Izmir, Turkey
1
Human CM and CMR have not been systematically studied by the neurophysiological methods in spite of their important functional role in the preservation of the spermatogenesis and ejaculation. In this communication, our previous and present related studies are summarized. Needle EMG analysis including C-SFEMG shows that MUAPs were similar to those obtained from chronic neurogenic atrophy but the CM functions are normal in the healthy adult males investigated. Although the voluntary control of CM is not required for the most part, Magnetic Coil Stimulation to scalp and L1-L3 root levels produces clear cut Motor responses. Central motor conduction time was longer than lower abdominal muscles. Genitofemoral nerve motor conduction to CM is comparable to similar peripheral nerves. Hystochemistry of CM demonstrates that CM is a striated muscle but fibers have multiple motor end plates. CMR is elicited from thoracic to sacral dermatomes but varied among the subjects. CMR is more sensitive to abdominal cold stimulation and highly responsive to tactile stimuli at the genitalia. There is a reflex linkage between the upper lumbar and the lower sacral spinal segments studied by CMR and bulbocavernosus reflex. This spinal circuit may be related with the ejaculatory process in man. It is concluded that human CM and CMR is different physiologically and morphologically from the other skeletal muscles and reflexes probably due to different embryological development of CM. WS4. Restoration of injured peripheral nerve function WS4-1 Neurophysiological measures following total C7 nerve transection Y. Zhu1 1 EMG Laboratory, Huashan Hospital, Fudan University, Shanghai, China Over the past two decades, cervical seventh nerve from the uninjured contralateral plexus has become a new source of axon donor to reinnervate the median nerve in patients with total brachial plexus avulsion lesion. A vascularized ulnar nerve graft is interposed between this and the median nerve within the injured limb to restore hand function. Several studies have reported that power in wrist and digital flexors might reach MRC3 to MRC4; the patients might be able to localize accurately touch to the thumb, index and middle finger. On the donor side, after the total C7 nerve transection the clinical recovery of the sensory and motor function is good. We have performed the following neurophysiological studies: 1. Wallerian degeneration: C7 nerve transection causes maximal reduction of the amplitude of the sensory nerve action potential (SNAP) in digit 1, 2, 3, and 4 by the 8th day post operation. 2. Cutaneous sensation and the size of SNAP: The initial decrease in pinprick perception gradually recovers to normal by from 2 to 10 months post operation. Assessed by the reduction of the amplitude of digital SNAP, the C7 root distribution is predominately in digit 2 and 3 (>67%), and also in digit 1 (50%) and 4 (40%). 3. Mapping of C7 dermatome: It covers much of the conventional C6 dermatome on the lateral aspect of the forearm, along with the index, middle fingers and thumb. 4. H-reflex from flexor carpi radialis (FCR): FCR is innervated by the C6 and C7 roots. The H-reflex is absent after C7 nerve transfer and reappears months later in the majority of cases. 5. Digital SEP: A decrement of over 70% in the amplitude of digital SNAP does not affect the latency or amplitude of the first cortical response. WS4-2 Electrodiagnosis as a prognostic factor H. Kwon1 1 Department of Physical Medicine & Rehabilitation, College of medicine, Korea University, Seoul, Korea The nature of injury is critical factor in deterniming the severity of the injury and the prognosis for full recovery. Compression neuropathy,
Oral Presentations: Workshops
to promote functional recovery of function following stroke and spinal cord injury. It is therefore somewhat surprising that the spinal cord is often not mentioned in relation to motor disorders. The spinal cord receives substantial dopaminergic innervation, which is essential for initiation of gait at least in animals. Could it be that pathological changes in this innervation is involved in the gait disturbance of Parkinson patients? Or in Restless Leg Syndrome? Several studies have documented altered transmission in spinal networks in patients with various motor disorders decades ago, but such findings appear not to have received much attention. Maybe it is time that we start minding the spinal cord and consider the role that it in all likelihood plays in movement disorders.
WS2-4 Inappropriate modulation of antagonistic inhibition at onset of voluntary contraction in Parkinson’s disease
WS2-2 Spinal interneurones R. Katz1 , V. Marchand1 Er 6 UPMC Med Phys & Readapt
1
Disynaptic Ia reciprocal inhibition from the peroneal nerve afferents to the soleus muscle was significantly increased after TES. On the other hand, the disynaptic Ia inhibition of the TA muscle by group Ia volleys from the tibial nerve was decreased in all subjects of 3 patients in whom H reflexes were detected in the TA muscle. TES might change transmission efficiency of two synapses originated from disynaptic Ia inhibitory interneurons of the TA muscle. We suggest that the facilitation of voluntary contraction in the agonist muscle and the reduction of the spasticity in the antagonist muscle by TES might result from enhancement of the synaptic transmission efficiency.
La Salpetriere hospital, France
Motor function (muscle tone, maintenance of posture and movement) is finally expressed by muscle contractions depending on the activity of motoneurones, the final common pathway, of motor activity. Characteristics of motoneurone discharge (number of motoneurones firing, their frequency of discharge and pattern of activation) is the reflect of an integration of activity in the different structures of the central nervous system (motor cortex, cerebellum, basal ganglia, vestibular system, spinal interneurones). Most of the data available concerning the knowledge of spinal interneurones involved in motor control have been drawn in experiments performed in reduced animal preparations. The introduction in the fiftees of intracellular recordings has allowed Eccles, Lundberg and their colleagues to describe the synaptic connections of spinal interneurones. However, it is obvious that such invasive methods cannot be used in humans but data obtained in animals cannot be transposed in humans without caution taking into account the phylogenetic evolution with the appearance of bipedal stance and gait. A pre-requisite to investigate spinal interneurones is the development of non-invasive methods unabling to investigate selectively these pathways in humans. These methods allow to study among others recurrent inhibition Ia and Ib inhibition, presynaptic Ia inhibition and homosynaptic depression, propriospinal pathways, monosynaptic Ia excitation, excitation by group II afferents or cutaneous muscle responses. Experiments performed during maintenance of posture, locomotion and voluntary movement in healthy subjects have allowed to reveal specific changes in the excitability of spinal interneurones linked to a given motor task. In central nervous system lesioned patients, they have brought arguments about the pathophysiology of muscle tone abnormalities and motor control disorders. TMS and tDCS applied to the motor cortex allow to induce non-invasive and reversible plasticity at cerebral and spinal levels. WS2-3 Disynaptic Ia reciprocal inhibition in stroke patients before and after therapeutic electrical stimulation Y. Masakado1 , Y. Muraoka2 , T. Ohta3 , Y. Tomita4 , A. Kimura3 1 Department of Rehabilitation Medicine, Tokai University School of Medicine, Kanagawa, Japan, 2 National Murayama Hospital, Japan, 3 Keio University Tsukigase Rehabilitation Center, Japan, 4 Department of Biosciences and Informatics, The Faculty of Science and Technology, Keio University, Japan Therapeutic effects of transcutaneous electrical stimulation (TES), such as reduction of spasticity and improvements in motor control, have often been observed. The purpose of this study is to evaluate the efficacy of TES on hemiplegic patients from the viewpoint of voluntary movement in paretic lower extremity and reciprocal Ia inhibition. The stimulation parameters were held at fixed values as follows: frequency at 20 Hz, monophasic rectangular waveform, pulse width at 0.3 ms, and mild contraction intensity. A 5-second stimulation followed by 15-second rest was repeated for 15 min. After TES, the surface EMG showed a reduction in co-contraction and change to reciprocated movements of quadriceps and hamstrings. These findings suggest improvements in voluntary movements of knee joints, though TES was applied on paretic lower leg. We also studied disynaptic Ia reciprocal inhibition between the soleus muscle and the tibialis anterior (TA) muscle before and after TES to the TA muscle. The amount of disynaptic Ia reciprocal inhibition was determined by the short latency suppression of the soleus or TA muscle H reflexes by conditioning stimulation of the antagonistic muscle nerves.
H. Morita1 1 Department of Medicine (Neurology & Rheumatology), Shinshu University, Matsumoto, Japan Spinal reflex activity in Parkinson’s disease (PD) have been studied at rest and during voluntary movement. Although reflex activities at rest have examined for many reflex pathways such as reciprocal Ia inhibition, heteronymous Ib inhibition, recurrent inhibition, and presynaptic inhibition, results are still controversial among studies. This may be due to deference of severity, effect of medication or age among studies. On the other hand, abnormal modulation of spinal reflex activity with voluntary movement, especially at onset of contraction, was common among studies. In normal subject, there is a clear reciprocal control that modulated supraspinaly at onset of contraction. When a subject performs dorsiflexion, the extent of reciprocal inhibition increases as a central modulation to inhibit motoneuronal activity of antagonists. During plantarflexion the reciprocal inhibition contrary decreases in normal subjects. Modulation of the inhibition with voluntary contraction was completely opposite to normal subjects. At onset of wrist flexion there was no modulation of reciprocal inhibition form extensors to flexor carpi radialis in PD, which should decrease in normal subjects. At onset of ankle dorsiflexion there was no reciprocal inhibition from tibialis anterior to soleus but was paradoxical facilitation in PD. Such paradoxical phenomenon was also observed with TMS induced facilitation to soleus H-reflex. In normal subjects, TMS facilitates soleus H-reflex at onset of plantarflexion. However, TMS inhibit soleus H-reflex at onset of plantarflexion. The latency of this inhibitory activity was a little longer than facilitation. Treatment of PD with medication or surgery improved some part of these abnormalities. These observations indicated that inappropriate supraspinal modulation of reciprocal control at onset of voluntary contraction related to motor symptoms of PD such as freezing phenomenon, although responsible descending pathway are still controversial. WS3. Neurophysiology of urination and pelvic floor muscles WS3-1 Sphincter physiology: with reference to neurologic/autonomic disorders R. Sakakibara1 1 Neurology, Internal Medicine, Sakura Medical Center, Toho University, Japan Anal and urethral sphincters participate actively in regulating bladder, bowel, and sexual function, with the former two being predominant. Anal and urethral sphincters are thought to share innervation. Internal sphincter is innervated by sympathetic noradrenergic fibers that originate from T12-L2 intermediolateral cell columns, whereas external sphincter is innervated by somatic fibers that originate from S2 3 anterior horn cells in the Onuf’s nucleus. Spinal sphincter descending fibers have not fully been determined in humans, but probably lie in the lateral columns. Anatomical and functional imaging studies suggest that brain structures relevant to the sphincter and the pelvic floor include area 4, supplementary motor area, frontal cortex, cerebellum, and basal ganglia. If one of these structures is affected in neurologic/autonomic disorders, sphincter function may alter. One particular example is multiple system atrophy (MSA), where a various combination of parkinsonian, cerebellar, and autonomic (including cardiovascular, urinary, and anorectal) dysfunction may occur. In MSA internal and external sphincter denervation occurs, which appears as open bladder neck at the start of bladder filling (internal) and neurogenic
29th International Congress of Clinical Neurophysiology changes in motor unit potential analysis of sphincter electromyography (EMG) (external). Since involvement of the sacral Onuf’s nucleus is extremely uncommon in idiopathic Parkinson’s disease (iPD), sphincter EMG can become a practical method to distinguish MSA from iPD. If sphincter does not relax properly on evacuation, it shows obstructed pattern in the urodynamic pressure-flow analysis. Detrusor (bladder)external sphincter dyssynergia is such a condition that originates from higher malfunction in MSA. Only recently, peripheral nerve lesion, e.g., e syndrome, is shown to cause detrusor-internal sphincter Guillain Barr´ dyssynergia, due probably to increased peripheral nerve firing and ephaptic transmission. We need to treat the sphincter properly in order to maximize the quality of life in patients and to avoid urinary complications. WS3-2 Neurophysiology of pelvic floor A. Tello1 1 Clinical Neurophysiology Department. Hospital Espanol de Mexico, Mexico Pelvic floor disorders affect one in four adult women of all ages. The etiology of these disorders is multifactorial and results from a combination of risk factors. The clinical picture varies and can be presented as pelvic organ prolapse, fecal or urinary incontinence and sexual dysfunction. With a comprehensive neurological history and physical examination, the clinician might suggest the diagnosis as to where or which of the control mechanism is affected. However, most times, it is difficult to draw a conclusion on clinical grounds only, as normal pelvic floor function involves several neural paths, both peripheral and central controllers, and somatic and autonomic nervous systems. Given the complexity of the system, it is recommended to perform, in addition to anatomic studies, electrodiagnostic tests, designed to investigate pelvic floor dysfunction of neural controllers. A number of tests are performed to evaluate pelvic floor muscles and external anal sphincter, including pudendal nerve conduction studies, sacral reflexes, somatosensory evoked potentials and motor evoked potentials. When lower motor neuron lesion is suspected, EMG of anal and urethral sphincters is the most appropriate test, since information about denervation/reinnervation can be drawn from this method. If the lesion is at the level of the sacral level, besides EMG examination, sacral reflexes give important information. Pudendal nerve terminal motor latencies (PNTMLs), examines conduction of nerve fibers rather than levels of innervation, and examine large myelinated fibers conduction rather than that of the unmyelinated fibers which enclose the autonomic innervation. In cases of upper motor neuron dysfunction, the utility of SEPs and MEPs is less clear. This discussion reviews the clinical usefulness, the strengths and pitfalls of each technique, in establishing the integrity of the peripheral innervation of the pelvic floor and how the combination of different methods help to determine the level of the lesion. WS3-3 Clinical study
neurophysiological tests in uroneurology
1
D.B. Vodusek Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
1
Neurophysiological tests are used in clinical practice for assessment of individual patients with uroanogenital disorders or pelvic pain to diagnose nervous system lesions, and to define dysfunction. Needle EMG and conduction studies (particularly bulbocavernosus reflex) are useful in diagnosing lesions within the lower (S2-S4) sacral reflex arcs, and are more sensitive (whereas SEPs are less sensitive) than clinical examination to detect abnormality. Sympathetic skin response recording is still mostly a research tool. Kinesiological sphincter EMG recordings demonstrate detrusor/sphincter, and bowel/sphincter discoordination in patients with CNS lesions. Application of sphincter EMG has revealed myogenic urethral sphincter hyperactivity as cause for urinary retention in women, thus defining a new clinical syndrome (Fowler syndrome). Neurophysiological methods have demonstrated the (partly) neuropathic cause of “genuine” stress urinary and anal incontinence. In conclusion, neurophysiological tests remain interesting for clinical research in patients with uroanogenital dysfunction. EMG with sacral reflex recording is diagnostic in patients with suspected conus, cauda equina, sacral root, pudendal and levator ani nerve involvement, and defines lower motor neuron and reflex arc lesions due to trauma, compression, inflammation and dysraphism.
S77 WS3-4 Human cremaster muscle (CM) and cremasteric reflex (CMR) C. Ertekin1 Department of Neurology and Clinical Neurophysiology, Ege University, Izmir, Turkey
1
Human CM and CMR have not been systematically studied by the neurophysiological methods in spite of their important functional role in the preservation of the spermatogenesis and ejaculation. In this communication, our previous and present related studies are summarized. Needle EMG analysis including C-SFEMG shows that MUAPs were similar to those obtained from chronic neurogenic atrophy but the CM functions are normal in the healthy adult males investigated. Although the voluntary control of CM is not required for the most part, Magnetic Coil Stimulation to scalp and L1-L3 root levels produces clear cut Motor responses. Central motor conduction time was longer than lower abdominal muscles. Genitofemoral nerve motor conduction to CM is comparable to similar peripheral nerves. Hystochemistry of CM demonstrates that CM is a striated muscle but fibers have multiple motor end plates. CMR is elicited from thoracic to sacral dermatomes but varied among the subjects. CMR is more sensitive to abdominal cold stimulation and highly responsive to tactile stimuli at the genitalia. There is a reflex linkage between the upper lumbar and the lower sacral spinal segments studied by CMR and bulbocavernosus reflex. This spinal circuit may be related with the ejaculatory process in man. It is concluded that human CM and CMR is different physiologically and morphologically from the other skeletal muscles and reflexes probably due to different embryological development of CM. WS4. Restoration of injured peripheral nerve function WS4-1 Neurophysiological measures following total C7 nerve transection Y. Zhu1 1 EMG Laboratory, Huashan Hospital, Fudan University, Shanghai, China Over the past two decades, cervical seventh nerve from the uninjured contralateral plexus has become a new source of axon donor to reinnervate the median nerve in patients with total brachial plexus avulsion lesion. A vascularized ulnar nerve graft is interposed between this and the median nerve within the injured limb to restore hand function. Several studies have reported that power in wrist and digital flexors might reach MRC3 to MRC4; the patients might be able to localize accurately touch to the thumb, index and middle finger. On the donor side, after the total C7 nerve transection the clinical recovery of the sensory and motor function is good. We have performed the following neurophysiological studies: 1. Wallerian degeneration: C7 nerve transection causes maximal reduction of the amplitude of the sensory nerve action potential (SNAP) in digit 1, 2, 3, and 4 by the 8th day post operation. 2. Cutaneous sensation and the size of SNAP: The initial decrease in pinprick perception gradually recovers to normal by from 2 to 10 months post operation. Assessed by the reduction of the amplitude of digital SNAP, the C7 root distribution is predominately in digit 2 and 3 (>67%), and also in digit 1 (50%) and 4 (40%). 3. Mapping of C7 dermatome: It covers much of the conventional C6 dermatome on the lateral aspect of the forearm, along with the index, middle fingers and thumb. 4. H-reflex from flexor carpi radialis (FCR): FCR is innervated by the C6 and C7 roots. The H-reflex is absent after C7 nerve transfer and reappears months later in the majority of cases. 5. Digital SEP: A decrement of over 70% in the amplitude of digital SNAP does not affect the latency or amplitude of the first cortical response. WS4-2 Electrodiagnosis as a prognostic factor H. Kwon1 1 Department of Physical Medicine & Rehabilitation, College of medicine, Korea University, Seoul, Korea The nature of injury is critical factor in deterniming the severity of the injury and the prognosis for full recovery. Compression neuropathy,