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Autonomic and sphincter disorders
SI05
Autonomic and sphincter disorders IpS8-01
I
Sphincter EMG in differentiating patients with autonomic failure and/or parkinsonism
D .B. Vodusek, Di vision o] Neu rology, University Medical Centr e, 1525 Ljubljana. Slove nia Multiple syst e m atroph y (MS A) manife sts as parkinsoni sm, cerebell ar, pyramidal, and auto nomic - inclu ding urinary, sexual and anorectal dysfunction (in any combination), and ma y mimi c other disorders. In MSA , Onu f' s nucleus degen erate s, and signs of dener vation and reinnerv ation appear on Concentric Needle (CN) EMG of sphincter and bulbo cavernosus mu scle s. In patien ts with probable MSA abno rmal EMG s have been found in 82- 100% - in all the different form s of the disease. Abn orm al findings can be found in patients who as yet hav e no urological or anorectal problem; on the other hand patients with Parkin son's disease and such problems as a rule do not show prominent EMG abnorma lities. The prevalence of abno rma lities in the early stages of MSA , ho wever, is uncl ear. There is as yet no consensus which EMG param eter is the most speci fic marker for MSA : pre senc e of abno rmal spontaneo us activi ty, prolon ged duration or increase d percentage of polyph asic moto r unit pot enti als, or an increase in fibre den sity on Single Fiber EMG. The sensitivity and specificity of EMG to distingu ish MSA from Parkinson ' s disease are good (0.80, 0.93), and ma y be good also to distinguish it from pure autonomic failur e; these data are not known for ataxias. EMG is not useful to distingui sh MSA from progressive supranuclear pal sy. and is generally les s specific in fem ale patients because of occasional sphincter denervation after vaginal deliveries.
Ips 8.o3
E. Stalberg", H. Naver", C. Swartling", C. Farnstrand". "Departm ent of Clinical Neurophysi ology; "Department of Neu rology; 3Departlllent of Dermatology, University Hospital. Uppsa la, Sweden Palm ar hyperh idro sis redu ces sig nificantly quality of life (Nav er, 1999 ). By local injec tion of Botulinum toxin A (Bo tox, Allergan Pharm aceu ticals ) in the palm the hyperhidrosis can be redu ced next to zero . For eac h treat ment , sma ll doses of Botox are injected at 50-80 different spots in the hand , depending on the size of the hand . At pre sen t more than 200 patient s have been tre ated in our prog ram. In addition to the positive effect of a dry hand, some of the patients nuticed a weakness in the injected hand a few days after treatment and remaining for a few month s. Among 37 hand s in this study, finger abduction and thumb opposition were reduced by more than 50% in 14% of the patients. Neurophysiological studies with nerve stim ulation showed redu ced motor amplitude by more than 50% in the thenar (84%) , hypothenar (24%) but very fe w in the first dorsal interosseus (3%). SFEMG showe d disturbed neu romu scul ar tran smission in the 3 cases where thi s was studied. Thi s weakness was well tolerated and did not refrain the patients to co me for a seco nd treatment when the effec t had waned after I I2~1 year. Con clusion : Local Bot ox treatment has a dram atic positive effect in cases of palm ar hyperhidrosis. However, neuromuscular transmi ssion disturbanc e occ urs frequently, but this is well tole rated in the light of the ov erall benefi ts of the treatment.
IpS8-04 I IpS8-02
I
Functional organisation of the autonomic nervous system in humans
B.G. Wall in . Department of Clinical Neurophysiology. Sahlg ren University Hospital. Giiteborg. Sweden The sympathetic and the parasympathetic ner vou s systems co nsis t of many subdiv isions, each of which is controlled selectively by specific reflex mech anisms. The differ ent subdivisions display no common 'sympathetic tone'. In humans, sympathetic traffic can be recorded in nerves to skin and muscle; to study other subdivi sion s ind irect methods must be used . During man eou vres, different autonomic subdivisions are acti vated or inhibited to different degrees , depending on the function al requiremen ts of the pro vocation. Therefore, careful standardisation is necessary in aut onomic fun ction tests. Combined microneurographi c and noradrenaline spillover studie s show that interindi vidual differ ence s in streng th of resting sympathetic activi ty are simil ar in ner ves to muscle, kidne y and heart. Although these tissues are influenced by baroreflexes, and are import ant for circulatory homeostasis, blood pressure is nevertheless similar in subjects with strong and weak sym pathetic traffic to these organs. Part of the reas on may be that strong sympathetic activity is counteracted by high level s of circulating vasodilating substances (e.g. NO ). New evide nce sugges ts that arteri al barorefl ex co ntrol of sympathetic activity is complex: occurrence and strength of the discharges are regulated differenti ally. In recordings from indi vidual sympathetic fibres, average firing frequency is around 0.5 Hz . Also during maneou vres with increased multiunit activity, and in pathological conditions with increased activity (e.g. cardiac failure) mean frequen cie s rarel y exceed 1 Hz, suggesting tha t incre ases of mul tiunit sympathetic activi ty are due , mainly to recrui tment of previ ously inac tive fibres.
Effect of treatment with Botox on patients with palmar hidrosis
Sympathetic ski n responses in carpal tunnel syndrome
R.G . Reis, A. Recchi a, C.E L. Souz a-Lima, J.L. Alonso Nieto, A.C. Paiva Mel o, Depart ments of Clinical Neurophysi ology and Neurology . Hospital do Servidor Publico Estadual, Siio Paulo. Brazil Objective: To stud y the usefuln ess of Symp ath etic Skin Respon ses (SSR) in assessing small unm yelinated fiber invol vement in Carpal Tunnel Synd rome (CTS). Methods: Thirty-nine patien ts (70 limbs) with CTS and 41 controls (82 limb s) were studied. Nerve conduction studies and SSR were done using a Dantec ~ electromyography apparatus. For SSR machine set-up : filters 0,52.0 kHz were used, sweep veloc ity was 500 ms and sensitivity has been adj usted to 0.5-1.0 mV. Acti ve and reference electrodes were placed on the palm and dors um of the hand . Laten cy (first negat ive deflecti on) and amplitude (peak to peak) were meas ured after 4 rando m stimuli of 10-50 rnA and 0.2 ms (to minimi ze the phen omenon of habituati on ). Results were anal ysed by the Stud en t t test. Re sult s: T he study of 70 limb s with CTS resulted in 48 classified as mild or moderate and 22 as seve re. The mean age was 41year s (vary ing fro m 20 to 62 yea rs) in CTS grou p and 42 years (varying from 31 to 53 years) in control subje cts. SSR was absent in 6 patients with CTS (4 mild or moderate, and two severe) and in none of the controls. The following mean ± SD values for amplitudes and latencies were obser ved: 1046 ± 479 fl.V and 1.39 ± 0 .20 ms in mild or moderate CTS , 1044 ± 461 fl.V and 1.24 ::': 0 .19 ms in severe CTS , 2048 :!: 1078 fl.V and 1.50 :!: 0 . 16 ms in cont rol limb s. A statistica lly significant co rrelation has been obtai ned only with amplitude me asurem ent obtained in CTS when compared to the controls (P < 0.0 I). Co nclusio ns: Autonomic dis turbances such as vaso motor and sudo motor sig ns are co mmo n in CTS, but unm yel inated axo ns are not accessible by routine nerve conduction studies . Symp atheti c skin respo nses may re veal
Sl 06
Platform sessions
dysfunction of these fibers. We found that the amplitude nf these responses, despite their intrinsic variability, may also be of value, but not its simple presence or absence.
Ipsa-os
I
Sympathetic skin response: to measure potential or conductance?
M. Pustovrh", R. Zidaric ", B. Konec ", M . Mihelin ' , T.S. Prevec". "Institute of Clinical Neurophysiology, University Medical Centre Ljubljana; "Faculty of Comput er Scien ces and lrfo rmatics. Ljubljana University, Lju bljana, Slovenia Mea surement of the potential changes of sympathetic skin response (SSR) is the standard neurophysiological method to evaluate sympathetic skin activity and function of the thin peripheral nerve fibres. The waveform of the sympathetic potential resp onse (SPR) is variable, usually biphasi c; initially it is a negative wave which is followed by a large positive deflection. Due to the generator mechanisms of the negative and positive deflection it is impossible to separate their contribution to the final waveform of the SPR. This makes SPR amplitude an unreli able measure. The waveform of the sympathetic conductance response (SCR) is monophasic, being a temporary increase in skin conductance, i.e. (skin resistance ). The laten cy of SCR is similar to the SPR latenc y. In addition to the latency measur ement s, also the SCR rise time , SCR amplitude, and SCR half recovery time were measured. To measure SCR, a digital conductance meter was constructed and conne cted to a conventional EMG machine . In young healthy voluntee rs SPR and SCR were recorded on the palm and sole surfaces to somato sensory and acoustic stimuli. To alter the SSR ampl itude, different intensity of stimuli and habituation were used. SPR and SCR charac teristics were compared. It seems that SCR provide s more reliable data to evaluate the amplitude of SSR than the traditional SPR recordings .
!PSa-06 I
Neurocardlogenic sy ncope: dynamics of clinical course predicts convutslons; ictal video-EEG study
R. Kuba' , T. Kara ", M. Brazdil ", J. Krizova", M. Soucek", M. Novak", I. Rektor. "Epilepsy Center Brno, Department of Neurology, St. Ann e 's Hospital, Bmo, Czech Republi c; "l st Department of Internal MedicinCardioangiology, St. Anne 's Hospital, Brno, Czech Republic Purpose: Length of asystolia is the only pred ictor of the probability of con vulsions during neurocardiogenic synco pe. We have analysed whether the dyn amics of initial phase of neurocardi ogenic syncope also correla tes with occurrence of convulsions. Methods: We retrospectively analysed I I patien ts (12 syncopes) suffering from neuro cardiogenic syncope using video -EEG reco rding. The videoEEG recordin g was performed during Head Upright Tilt Table Test (HUT test). We evaluated several electroclinical and clinical time-relat ed parameters. AI time period from the first subjective clinical sym ptom (presyncopal aura) to the change in EEG. BI time period from the first subjectiv e clinica l symptom (presyncopal aura) to the onset of polymorphi c delta activity (the typical ictal EEG pattern of diffuse cerebral hypoperfu sion). CI time peri od from the first subjec tive clinical symptom (presyncopal aura) to the loss of consciousness. All these time-related parameters reflect the dynamics of the initial phase of neuro cardiogenic syncope. Con vulsions occurred in 6 syncopes (convulsive syncope), 6 of them were conv ulsions-free (non-co nvulsive syncope). Both groups were compared. Results: Paired t test showed that all 3 measured parameters are significantly shorter in the group of convulsive syncopes (P < 0.05) . Conclusion: We have found that the dynamics of initial phase of neurocardiogenic syncope significantl y correlates with the probability of the occurrence of convulsions. Thu s besides the length of asystoli a, the dynamics of the development of neurocardiogcnic syncope is yet anoth er predictor of the of the possibility of convulsions during this type of syncope.
Ipsa-or
I
Standardisation of anal sphincter electromyography: comparison of quantitative methods
S. Podnar", D.B. Vodusek", E. Stalberg'', "Institute of Clinical Neurophysiology, Division of Neurolog y, University Medical Centre Ljubljana, Slovenia ; "Department of Clinical Neurophysiology. University Hospital, Uppsala, Sweden For direct comparison of 4 different quantitative EMG method s the taped sig nal from health y subjects (to obtain normative data) and neuropathic subjects (to analyse sensitivitie s) was analysed. Fifty-five patients (2 1 women, 34 men), 5 or more months after cauda/conus lesion, with sensory deficit, and 64 subjec ts (44 women, 20 men) without pelvic or neurological disorders were studied. Concentri c needle electrodes and an adva nced EMG system with standard settings (filters: 5-10 000 Hz) were used . Ten to twenty MUPs were meas ured manually using the triggerdelay and the 'frozen screen ' or by computer (multi-MUP analysis). Twenty interference pattern samples were measured using the Tum/ Amplitude (T/A) analysis. MUP parameter values obtained by the 3 different methods differed significantl y. Using mean/'outlier' limits the 3 MUP analysis methods detected between 44 and 57% of neuropathic muscles, using the mean, and betwe en 44 and 49% using the 'outlier' limits. Cumulative sensitivitie s were in all 3 method s between 55 and 57%, while the sensitivity of the TI A analysis was 33%. Tn conclusion , separate MUP normative values are needed for the different MUP analysis methods. The sensitivities to detect neuropathic changes in the EAS are similar. whereas the sensiti vity of the TI A analysis is lower. The relative ly low sensitivities obtained in our study are probabl y due to inclusion of patients with mild injuries.
Ipsa-oa I
Sympathetic skin r esponse in hyperhidrotic patients treated with botulinum toxin injections
R. Plasrnati", F. Pastorelli ", V. Tugnoli", M. Franca' , C.A. Tassinari' . "Department of Neuroscience, University of Bologna, Bellaria Hospital, Bologna, Italy; "Department ofNeurology, S. Anna Hospital, Ferrara, Italy The sympathetic skin respon se (SSR) was studied in 8 patient s (5 males and 3 female s, age 22-59 years) affected by idiopathic focal or generalised hyperhidrosis. SSR was recorded by disk electrodes placed on both hands, following electrical stimulati on of the median nerve at wrist, before and after treatment with subcutaneous injections of Botulinum toxin type A (Dysport). SSR was recorded with 4 different montages: (l) pal m-dorsum ; (2) palm-palm; (3) dorsum-dorsum ; and (4) palm -nail montage. SSR was performed in 10 healthy subjects as control group. Statistical analysis was performed by Student' s t test. Basal SSR was compared bet ween normal and hyperhidrotic subjects. Tn patients SSR. obtained with different montages , was compared before and after treatment. Before treatment: latency and amplitude of palm -dorsum SSR were superp osable to normative data. SSR latencies in the dorsum-dorsum derivation were statistically different from SSR laten cies obtained with the other monta ges, while no statistical difference was noted between SSR latencies measured with the first, second and fourth montage. Comparisons of the amplitude of palmdorsum/palm-n ail responses and palm -palm/d orsum-dorsum responses did not show any statistically significant difference. After treatment (7 days): sweat secretion disappeared or was reduced in all patien ts. SSR was reduced in amplitude in all cases but disapp eared only in anhidrotic hands. In all patient s, SSR reappeared 3-4-months afte r treatment but the amplitude reached normal values only 10-1 2 month s after treatment, associa ted with reappearance of hyperhidrosis. SSR is a sensitive method to detect focal anhidrosis , therefore it can be a reliable meth od to evaluate the effectiveness of botulinum toxin treatment. Sensitivity of the test was also confirmed by the early dete ction of a recovery of SSR after treatment , without concomitant reappearance of clinical symptoms.
Platform sessions
!PS8-09 I
Quantitative assessment of MRI lesions in monitoring the cardiovascular autonomic dysfunction
A. Saari', U. Tolonen'', E. Paakldl c, V. Myllyla", "Department of Neurology; "Department of Clinical Neurophysiology; 'Department of Diagnostic Radiology, University Hospital, Oulu, Finland It is well known that multiple sclerosis (MS) is associated with many clinical manifestations of autonomic failure. In the present study we investigated correlations between quantitative MRI lesion load in different brain regions and cardiovascular autonomic dysfunction measured by standard cardiovascular reflexes in a group of 51 MS patients. The total volume of
S107
intracranial MS lesions correlated with the severity of MS expressed by the EDSS score (P < 0.001) and with decreased diastolic blood pressure (BP) responses in tilt table testing at 2 min (P < 0.05) after tilting. The total midbrain lesion volume correlated with decreased BP responses immediately (diastolic, P < 0.05), at 2 min (diastolic, P < 0.05), and at 7 min (diastolic, P < 0.05) after tilting. The total parietal MS lesion volume correlated with decreased BP responses at 2 min (diastolic, P < 0.05) after tilting. There were no correlations of MRI lesion load with other cardiovascular tests (normal and deep breathing and isometric test). MS seems to result in cardiovascular dysregulation appearing in BP responses. According to our MRI-data midbrain MS-lesion account for the most frequent cardiovascular disturbances in patients with MS.
Autonomic and sphincter disorders IpS8-01
I
Sphincter EMG in differentiating patients with autonomic failure and/or parkinsonism
D .B. Vodusek, Di vision o] Neu rology, University Medical Centr e, 1525 Ljubljana. Slove nia Multiple syst e m atroph y (MS A) manife sts as parkinsoni sm, cerebell ar, pyramidal, and auto nomic - inclu ding urinary, sexual and anorectal dysfunction (in any combination), and ma y mimi c other disorders. In MSA , Onu f' s nucleus degen erate s, and signs of dener vation and reinnerv ation appear on Concentric Needle (CN) EMG of sphincter and bulbo cavernosus mu scle s. In patien ts with probable MSA abno rmal EMG s have been found in 82- 100% - in all the different form s of the disease. Abn orm al findings can be found in patients who as yet hav e no urological or anorectal problem; on the other hand patients with Parkin son's disease and such problems as a rule do not show prominent EMG abnorma lities. The prevalence of abno rma lities in the early stages of MSA , ho wever, is uncl ear. There is as yet no consensus which EMG param eter is the most speci fic marker for MSA : pre senc e of abno rmal spontaneo us activi ty, prolon ged duration or increase d percentage of polyph asic moto r unit pot enti als, or an increase in fibre den sity on Single Fiber EMG. The sensitivity and specificity of EMG to distingu ish MSA from Parkinson ' s disease are good (0.80, 0.93), and ma y be good also to distinguish it from pure autonomic failur e; these data are not known for ataxias. EMG is not useful to distingui sh MSA from progressive supranuclear pal sy. and is generally les s specific in fem ale patients because of occasional sphincter denervation after vaginal deliveries.
Ips 8.o3
E. Stalberg", H. Naver", C. Swartling", C. Farnstrand". "Departm ent of Clinical Neurophysi ology; "Department of Neu rology; 3Departlllent of Dermatology, University Hospital. Uppsa la, Sweden Palm ar hyperh idro sis redu ces sig nificantly quality of life (Nav er, 1999 ). By local injec tion of Botulinum toxin A (Bo tox, Allergan Pharm aceu ticals ) in the palm the hyperhidrosis can be redu ced next to zero . For eac h treat ment , sma ll doses of Botox are injected at 50-80 different spots in the hand , depending on the size of the hand . At pre sen t more than 200 patient s have been tre ated in our prog ram. In addition to the positive effect of a dry hand, some of the patients nuticed a weakness in the injected hand a few days after treatment and remaining for a few month s. Among 37 hand s in this study, finger abduction and thumb opposition were reduced by more than 50% in 14% of the patients. Neurophysiological studies with nerve stim ulation showed redu ced motor amplitude by more than 50% in the thenar (84%) , hypothenar (24%) but very fe w in the first dorsal interosseus (3%). SFEMG showe d disturbed neu romu scul ar tran smission in the 3 cases where thi s was studied. Thi s weakness was well tolerated and did not refrain the patients to co me for a seco nd treatment when the effec t had waned after I I2~1 year. Con clusion : Local Bot ox treatment has a dram atic positive effect in cases of palm ar hyperhidrosis. However, neuromuscular transmi ssion disturbanc e occ urs frequently, but this is well tole rated in the light of the ov erall benefi ts of the treatment.
IpS8-04 I IpS8-02
I
Functional organisation of the autonomic nervous system in humans
B.G. Wall in . Department of Clinical Neurophysiology. Sahlg ren University Hospital. Giiteborg. Sweden The sympathetic and the parasympathetic ner vou s systems co nsis t of many subdiv isions, each of which is controlled selectively by specific reflex mech anisms. The differ ent subdivisions display no common 'sympathetic tone'. In humans, sympathetic traffic can be recorded in nerves to skin and muscle; to study other subdivi sion s ind irect methods must be used . During man eou vres, different autonomic subdivisions are acti vated or inhibited to different degrees , depending on the function al requiremen ts of the pro vocation. Therefore, careful standardisation is necessary in aut onomic fun ction tests. Combined microneurographi c and noradrenaline spillover studie s show that interindi vidual differ ence s in streng th of resting sympathetic activi ty are simil ar in ner ves to muscle, kidne y and heart. Although these tissues are influenced by baroreflexes, and are import ant for circulatory homeostasis, blood pressure is nevertheless similar in subjects with strong and weak sym pathetic traffic to these organs. Part of the reas on may be that strong sympathetic activity is counteracted by high level s of circulating vasodilating substances (e.g. NO ). New evide nce sugges ts that arteri al barorefl ex co ntrol of sympathetic activity is complex: occurrence and strength of the discharges are regulated differenti ally. In recordings from indi vidual sympathetic fibres, average firing frequency is around 0.5 Hz . Also during maneou vres with increased multiunit activity, and in pathological conditions with increased activity (e.g. cardiac failure) mean frequen cie s rarel y exceed 1 Hz, suggesting tha t incre ases of mul tiunit sympathetic activi ty are due , mainly to recrui tment of previ ously inac tive fibres.
Effect of treatment with Botox on patients with palmar hidrosis
Sympathetic ski n responses in carpal tunnel syndrome
R.G . Reis, A. Recchi a, C.E L. Souz a-Lima, J.L. Alonso Nieto, A.C. Paiva Mel o, Depart ments of Clinical Neurophysi ology and Neurology . Hospital do Servidor Publico Estadual, Siio Paulo. Brazil Objective: To stud y the usefuln ess of Symp ath etic Skin Respon ses (SSR) in assessing small unm yelinated fiber invol vement in Carpal Tunnel Synd rome (CTS). Methods: Thirty-nine patien ts (70 limbs) with CTS and 41 controls (82 limb s) were studied. Nerve conduction studies and SSR were done using a Dantec ~ electromyography apparatus. For SSR machine set-up : filters 0,52.0 kHz were used, sweep veloc ity was 500 ms and sensitivity has been adj usted to 0.5-1.0 mV. Acti ve and reference electrodes were placed on the palm and dors um of the hand . Laten cy (first negat ive deflecti on) and amplitude (peak to peak) were meas ured after 4 rando m stimuli of 10-50 rnA and 0.2 ms (to minimi ze the phen omenon of habituati on ). Results were anal ysed by the Stud en t t test. Re sult s: T he study of 70 limb s with CTS resulted in 48 classified as mild or moderate and 22 as seve re. The mean age was 41year s (vary ing fro m 20 to 62 yea rs) in CTS grou p and 42 years (varying from 31 to 53 years) in control subje cts. SSR was absent in 6 patients with CTS (4 mild or moderate, and two severe) and in none of the controls. The following mean ± SD values for amplitudes and latencies were obser ved: 1046 ± 479 fl.V and 1.39 ± 0 .20 ms in mild or moderate CTS , 1044 ± 461 fl.V and 1.24 ::': 0 .19 ms in severe CTS , 2048 :!: 1078 fl.V and 1.50 :!: 0 . 16 ms in cont rol limb s. A statistica lly significant co rrelation has been obtai ned only with amplitude me asurem ent obtained in CTS when compared to the controls (P < 0.0 I). Co nclusio ns: Autonomic dis turbances such as vaso motor and sudo motor sig ns are co mmo n in CTS, but unm yel inated axo ns are not accessible by routine nerve conduction studies . Symp atheti c skin respo nses may re veal
Sl 06
Platform sessions
dysfunction of these fibers. We found that the amplitude nf these responses, despite their intrinsic variability, may also be of value, but not its simple presence or absence.
Ipsa-os
I
Sympathetic skin response: to measure potential or conductance?
M. Pustovrh", R. Zidaric ", B. Konec ", M . Mihelin ' , T.S. Prevec". "Institute of Clinical Neurophysiology, University Medical Centre Ljubljana; "Faculty of Comput er Scien ces and lrfo rmatics. Ljubljana University, Lju bljana, Slovenia Mea surement of the potential changes of sympathetic skin response (SSR) is the standard neurophysiological method to evaluate sympathetic skin activity and function of the thin peripheral nerve fibres. The waveform of the sympathetic potential resp onse (SPR) is variable, usually biphasi c; initially it is a negative wave which is followed by a large positive deflection. Due to the generator mechanisms of the negative and positive deflection it is impossible to separate their contribution to the final waveform of the SPR. This makes SPR amplitude an unreli able measure. The waveform of the sympathetic conductance response (SCR) is monophasic, being a temporary increase in skin conductance, i.e. (skin resistance ). The laten cy of SCR is similar to the SPR latenc y. In addition to the latency measur ement s, also the SCR rise time , SCR amplitude, and SCR half recovery time were measured. To measure SCR, a digital conductance meter was constructed and conne cted to a conventional EMG machine . In young healthy voluntee rs SPR and SCR were recorded on the palm and sole surfaces to somato sensory and acoustic stimuli. To alter the SSR ampl itude, different intensity of stimuli and habituation were used. SPR and SCR charac teristics were compared. It seems that SCR provide s more reliable data to evaluate the amplitude of SSR than the traditional SPR recordings .
!PSa-06 I
Neurocardlogenic sy ncope: dynamics of clinical course predicts convutslons; ictal video-EEG study
R. Kuba' , T. Kara ", M. Brazdil ", J. Krizova", M. Soucek", M. Novak", I. Rektor. "Epilepsy Center Brno, Department of Neurology, St. Ann e 's Hospital, Bmo, Czech Republi c; "l st Department of Internal MedicinCardioangiology, St. Anne 's Hospital, Brno, Czech Republic Purpose: Length of asystolia is the only pred ictor of the probability of con vulsions during neurocardiogenic synco pe. We have analysed whether the dyn amics of initial phase of neurocardi ogenic syncope also correla tes with occurrence of convulsions. Methods: We retrospectively analysed I I patien ts (12 syncopes) suffering from neuro cardiogenic syncope using video -EEG reco rding. The videoEEG recordin g was performed during Head Upright Tilt Table Test (HUT test). We evaluated several electroclinical and clinical time-relat ed parameters. AI time period from the first subjective clinical sym ptom (presyncopal aura) to the change in EEG. BI time period from the first subjectiv e clinica l symptom (presyncopal aura) to the onset of polymorphi c delta activity (the typical ictal EEG pattern of diffuse cerebral hypoperfu sion). CI time peri od from the first subjec tive clinical symptom (presyncopal aura) to the loss of consciousness. All these time-related parameters reflect the dynamics of the initial phase of neuro cardiogenic syncope. Con vulsions occurred in 6 syncopes (convulsive syncope), 6 of them were conv ulsions-free (non-co nvulsive syncope). Both groups were compared. Results: Paired t test showed that all 3 measured parameters are significantly shorter in the group of convulsive syncopes (P < 0.05) . Conclusion: We have found that the dynamics of initial phase of neurocardiogenic syncope significantl y correlates with the probability of the occurrence of convulsions. Thu s besides the length of asystoli a, the dynamics of the development of neurocardiogcnic syncope is yet anoth er predictor of the of the possibility of convulsions during this type of syncope.
Ipsa-or
I
Standardisation of anal sphincter electromyography: comparison of quantitative methods
S. Podnar", D.B. Vodusek", E. Stalberg'', "Institute of Clinical Neurophysiology, Division of Neurolog y, University Medical Centre Ljubljana, Slovenia ; "Department of Clinical Neurophysiology. University Hospital, Uppsala, Sweden For direct comparison of 4 different quantitative EMG method s the taped sig nal from health y subjects (to obtain normative data) and neuropathic subjects (to analyse sensitivitie s) was analysed. Fifty-five patients (2 1 women, 34 men), 5 or more months after cauda/conus lesion, with sensory deficit, and 64 subjec ts (44 women, 20 men) without pelvic or neurological disorders were studied. Concentri c needle electrodes and an adva nced EMG system with standard settings (filters: 5-10 000 Hz) were used . Ten to twenty MUPs were meas ured manually using the triggerdelay and the 'frozen screen ' or by computer (multi-MUP analysis). Twenty interference pattern samples were measured using the Tum/ Amplitude (T/A) analysis. MUP parameter values obtained by the 3 different methods differed significantl y. Using mean/'outlier' limits the 3 MUP analysis methods detected between 44 and 57% of neuropathic muscles, using the mean, and betwe en 44 and 49% using the 'outlier' limits. Cumulative sensitivitie s were in all 3 method s between 55 and 57%, while the sensitivity of the TI A analysis was 33%. Tn conclusion , separate MUP normative values are needed for the different MUP analysis methods. The sensitivities to detect neuropathic changes in the EAS are similar. whereas the sensiti vity of the TI A analysis is lower. The relative ly low sensitivities obtained in our study are probabl y due to inclusion of patients with mild injuries.
Ipsa-oa I
Sympathetic skin r esponse in hyperhidrotic patients treated with botulinum toxin injections
R. Plasrnati", F. Pastorelli ", V. Tugnoli", M. Franca' , C.A. Tassinari' . "Department of Neuroscience, University of Bologna, Bellaria Hospital, Bologna, Italy; "Department ofNeurology, S. Anna Hospital, Ferrara, Italy The sympathetic skin respon se (SSR) was studied in 8 patient s (5 males and 3 female s, age 22-59 years) affected by idiopathic focal or generalised hyperhidrosis. SSR was recorded by disk electrodes placed on both hands, following electrical stimulati on of the median nerve at wrist, before and after treatment with subcutaneous injections of Botulinum toxin type A (Dysport). SSR was recorded with 4 different montages: (l) pal m-dorsum ; (2) palm-palm; (3) dorsum-dorsum ; and (4) palm -nail montage. SSR was performed in 10 healthy subjects as control group. Statistical analysis was performed by Student' s t test. Basal SSR was compared bet ween normal and hyperhidrotic subjects. Tn patients SSR. obtained with different montages , was compared before and after treatment. Before treatment: latency and amplitude of palm -dorsum SSR were superp osable to normative data. SSR latencies in the dorsum-dorsum derivation were statistically different from SSR laten cies obtained with the other monta ges, while no statistical difference was noted between SSR latencies measured with the first, second and fourth montage. Comparisons of the amplitude of palmdorsum/palm-n ail responses and palm -palm/d orsum-dorsum responses did not show any statistically significant difference. After treatment (7 days): sweat secretion disappeared or was reduced in all patien ts. SSR was reduced in amplitude in all cases but disapp eared only in anhidrotic hands. In all patient s, SSR reappeared 3-4-months afte r treatment but the amplitude reached normal values only 10-1 2 month s after treatment, associa ted with reappearance of hyperhidrosis. SSR is a sensitive method to detect focal anhidrosis , therefore it can be a reliable meth od to evaluate the effectiveness of botulinum toxin treatment. Sensitivity of the test was also confirmed by the early dete ction of a recovery of SSR after treatment , without concomitant reappearance of clinical symptoms.
Platform sessions
!PS8-09 I
Quantitative assessment of MRI lesions in monitoring the cardiovascular autonomic dysfunction
A. Saari', U. Tolonen'', E. Paakldl c, V. Myllyla", "Department of Neurology; "Department of Clinical Neurophysiology; 'Department of Diagnostic Radiology, University Hospital, Oulu, Finland It is well known that multiple sclerosis (MS) is associated with many clinical manifestations of autonomic failure. In the present study we investigated correlations between quantitative MRI lesion load in different brain regions and cardiovascular autonomic dysfunction measured by standard cardiovascular reflexes in a group of 51 MS patients. The total volume of
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intracranial MS lesions correlated with the severity of MS expressed by the EDSS score (P < 0.001) and with decreased diastolic blood pressure (BP) responses in tilt table testing at 2 min (P < 0.05) after tilting. The total midbrain lesion volume correlated with decreased BP responses immediately (diastolic, P < 0.05), at 2 min (diastolic, P < 0.05), and at 7 min (diastolic, P < 0.05) after tilting. The total parietal MS lesion volume correlated with decreased BP responses at 2 min (diastolic, P < 0.05) after tilting. There were no correlations of MRI lesion load with other cardiovascular tests (normal and deep breathing and isometric test). MS seems to result in cardiovascular dysregulation appearing in BP responses. According to our MRI-data midbrain MS-lesion account for the most frequent cardiovascular disturbances in patients with MS.