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Sensorimotor compared to autonomic polyneuropathy in diabetics
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with surface electrodes to detect a c t i v i t i e s of the fastest f i b r e s . Mostly a r e l a t i v e l y large " d i f f e r e n t " electrode (e.g. ~=lo mm) is positioned on the muscle b e l l y more or less overlapping the endplate region. By those surface electrodes m u l t i p l e superpositions of motor u n i t current f i e l d s are recorded (espec i a l l y with muscles consisting of several bundles, e . g . M . e x t . d i g . b r . ) which cause " i r r e g u l a r " i n t r a i n d i v i d u a l v a r i a t i o n s of measured latencies c o n t r i b u t i n g to the v a r i a b i l i t y in s e r i a l follow-up studies. A new method f o r easy motor-point l o c a l i z a t i o n with adequate accuracy has been developed. Smaller surface electrodes placed as close as possible to the motor point pick up c h a r a c t e r i s t i c a l l y shaped signals best suited to recognize the f i r s t depolarization as well as pathological shape v a r i a t i o n s . Multielectrode recording gives more detailed information about the parameters i n f l u e n c i n g the r e p r o d u c i b i l i t y of latencies. Consideration and, as f a r as possible, exclusion of various influences combined with microcomputer-based automated signal anal y s i s r e s u l t in a marked improvement in latency accuracy and r e p r o d u c i b i l i t y which can not be achieved by manual p o s i t i o n i n g of single electrodes and manual s i g n a l - e v a l u a t i o n : nerve conduction time (between marked skin points) obtained from the same subject during 14 days experimental period showed an overall v a r i a t i o n characterized by 2 S.D. = o,15 milliseconds only.
F264 THE DIAGNOSTIC VALUE OF SPINAL AND CORTICAL RECORDED"TIBIAL NERVE SEP's"
RIFFEL, B., ST~HR, M., REICH, H.~ Neurologische Klinik, 89 Augsburg, FRG Somatosensory evoked p o t e n t i a l s have c l e a r l y proven to be s p e c i f i c a l l y a l tered in MS patients, i t s usefulness, however, in patients with other than demyelinating diseases is less clear. This study compares latencies and amplitudes obtained after stimulation of the t i b i a l nerve of a MS- and spinal tumor group. Measurements were compared with those obtained previously from a healthy population study. Delayed sensory conduction of both absolute latencies and side differences of the P40 was demonstrated in 91% of MS patients. The additional recording of spinal evoked p o t e n t i a l s over L4/L5, D12/L1 and CI/C2 did not s i g n i f i c a n t l y increase the percentage of pathological responses, but allowed the d i f f e r e n t i a t i o n in spinal and supraspinal conduction delays of the sensory pathway. The absolute latencies were generally w i t h i n normal l i m i t s in the tumor group. The comparison however of P40/S quotient (normal above 0.9) of both study groups proved to be a valuable indicator of a p a r t i a l block of dorsal column conduction in tumor p a t i e n t s . 36% of tumor patients had a s i g n i f i c a n t decrease in the P40/S quotient (less than 0.5), another 29% had a reduction of less than 0.9 suspicious for a p a r t i a l block.
F265 SENSORIMOTORCOMPAREDTO AUTONOMICPOLYNEUROPATHYIN DIABETICS RIMP~L, J . , FRENZEL, H.P.~ JABLONKA, S., KREIJENVELD, S . and LEHMANN, H.J., Department of Neurology, Univ~ersity Hospital, Essen, FRG Diabetes m e l l i t u s is f r e q u e n t l y associated with sensorymotor or autonomic polyneuropathv (PNP). In a group of diabetics the c l i n i c a l signs of e i t h e r
S159
form of PNP were compared with n. s u r a l i s neurography and c i r c u l a t o r y regulation tests. - Diabetics were i n p a t i e n t s , not older than 60 years, and free of any other diseases than diabetes, PNP or diabetic retinopathy. Healthy subjects served as controls (matched p a i r s ) . - C l i n i c a l evaluation included common physical and neurological examination and routine laborat o r y tests. Long term diabetic regulation was c o n t r o l l e d by Hb(Alc) quantif i c a t i o n . The diagnosis of PNP was based on evaluation of r e f l e x status, motor f u n c t i o n , s e n s i t i v i t y f o r touch, p o s i t i o n , v i b r a t i o n , pain, and temperature. Measurement of n. s u r a l i s conduction v e l o c i t y was completed by evaluation of r e f r a c t o r y period as an e l e c t r o p h y s i o l o g i c a l correlate of sensory PNP. For t e s t i n g autonomic r e g u l a t i o n ECG-frequency and a r t e r i a l blood pressure were registered while patients were exerting a continuously repeated pressure with the r i g h t hand, expiring air against a resistance or during passive t i p p i n g manoeuvre from horizontal to v e r t i c a l p o s i t i o n . Evaluation of the data from c l i n i c a l neurologic state, n. s u r a l i s neurography, and autonomic r e g u l a t i o n , obtained by d i f f e r e n t authors under blind conditions, demonstrates inconsistency of the r e s u l t s of e i t h e r of the i n vestigated parameters. Involvement of the autonomic nervous system is not in every case combined with sensorymotor or neurographic f i n d i n g s and vice versa.
F266 THE VALUE OF DIFFERENT ELECTROPHYSIOLOGICALPROCEDURES IN THE DIAGNOSIS OF MULTIPLE SCLEROSIS. COMPARISONWITH OTHER LABORATORYTESTS IN 180 PATIENTS RINGELSTEIN,E.B., HACKE,W., ZEUMER,H., EIDEN,G.~ Department of Neurology, Technical High School, Goethestrasse 27-29, D- 51 Aachen, FRG In order to determine the diagnostic value of various approaches in patients with m u l t i p l e sclerosis (MS), the c l i n i c a l , e l e c t r o p h y s i o l o g i c a l (VEP, SSEP, OOR), neuroradiological (CT) and CSF-parameters were assessed and compared. The system of Confavreux et al (1980) (termed CON) was used to c l a s s i f y the patients according to the p r o b a b i l i t y of MS-diagnosis from a c l i n i c a l point of view. This system also considers the elevation IgG in CSF. I f a l l the above mentioned data were considered ( A l l ) the r a t i o of patients with d e f i n i t e diagnosis of MS increased considerably. Parameters were analyzed as to t h e i r cont r i b u t i o n to the r e l i a b i l i t y of MS-diagnosis. Thus, the most informative procedures could be defined. The conclusive r e s u l t s are summarized in the f o l l o wing table: Parameter R e l i a b i l i t y of MS-diagnosis ( r e l a t i v e frequency) definite probable possible CON 58% 27% 15% CON plus CT 69% 21% 10% CON plus complete electrophysiology 80% 14% 6% ALL 84% 10% 6% CON plus OOR 58% 28% 14% CON plus Medianus-SSEP 59% 28% 13% CON plus Suralis-SSEP 60% 27% 13% CON plus VEP 66% 21% 13%
with surface electrodes to detect a c t i v i t i e s of the fastest f i b r e s . Mostly a r e l a t i v e l y large " d i f f e r e n t " electrode (e.g. ~=lo mm) is positioned on the muscle b e l l y more or less overlapping the endplate region. By those surface electrodes m u l t i p l e superpositions of motor u n i t current f i e l d s are recorded (espec i a l l y with muscles consisting of several bundles, e . g . M . e x t . d i g . b r . ) which cause " i r r e g u l a r " i n t r a i n d i v i d u a l v a r i a t i o n s of measured latencies c o n t r i b u t i n g to the v a r i a b i l i t y in s e r i a l follow-up studies. A new method f o r easy motor-point l o c a l i z a t i o n with adequate accuracy has been developed. Smaller surface electrodes placed as close as possible to the motor point pick up c h a r a c t e r i s t i c a l l y shaped signals best suited to recognize the f i r s t depolarization as well as pathological shape v a r i a t i o n s . Multielectrode recording gives more detailed information about the parameters i n f l u e n c i n g the r e p r o d u c i b i l i t y of latencies. Consideration and, as f a r as possible, exclusion of various influences combined with microcomputer-based automated signal anal y s i s r e s u l t in a marked improvement in latency accuracy and r e p r o d u c i b i l i t y which can not be achieved by manual p o s i t i o n i n g of single electrodes and manual s i g n a l - e v a l u a t i o n : nerve conduction time (between marked skin points) obtained from the same subject during 14 days experimental period showed an overall v a r i a t i o n characterized by 2 S.D. = o,15 milliseconds only.
F264 THE DIAGNOSTIC VALUE OF SPINAL AND CORTICAL RECORDED"TIBIAL NERVE SEP's"
RIFFEL, B., ST~HR, M., REICH, H.~ Neurologische Klinik, 89 Augsburg, FRG Somatosensory evoked p o t e n t i a l s have c l e a r l y proven to be s p e c i f i c a l l y a l tered in MS patients, i t s usefulness, however, in patients with other than demyelinating diseases is less clear. This study compares latencies and amplitudes obtained after stimulation of the t i b i a l nerve of a MS- and spinal tumor group. Measurements were compared with those obtained previously from a healthy population study. Delayed sensory conduction of both absolute latencies and side differences of the P40 was demonstrated in 91% of MS patients. The additional recording of spinal evoked p o t e n t i a l s over L4/L5, D12/L1 and CI/C2 did not s i g n i f i c a n t l y increase the percentage of pathological responses, but allowed the d i f f e r e n t i a t i o n in spinal and supraspinal conduction delays of the sensory pathway. The absolute latencies were generally w i t h i n normal l i m i t s in the tumor group. The comparison however of P40/S quotient (normal above 0.9) of both study groups proved to be a valuable indicator of a p a r t i a l block of dorsal column conduction in tumor p a t i e n t s . 36% of tumor patients had a s i g n i f i c a n t decrease in the P40/S quotient (less than 0.5), another 29% had a reduction of less than 0.9 suspicious for a p a r t i a l block.
F265 SENSORIMOTORCOMPAREDTO AUTONOMICPOLYNEUROPATHYIN DIABETICS RIMP~L, J . , FRENZEL, H.P.~ JABLONKA, S., KREIJENVELD, S . and LEHMANN, H.J., Department of Neurology, Univ~ersity Hospital, Essen, FRG Diabetes m e l l i t u s is f r e q u e n t l y associated with sensorymotor or autonomic polyneuropathv (PNP). In a group of diabetics the c l i n i c a l signs of e i t h e r
S159
form of PNP were compared with n. s u r a l i s neurography and c i r c u l a t o r y regulation tests. - Diabetics were i n p a t i e n t s , not older than 60 years, and free of any other diseases than diabetes, PNP or diabetic retinopathy. Healthy subjects served as controls (matched p a i r s ) . - C l i n i c a l evaluation included common physical and neurological examination and routine laborat o r y tests. Long term diabetic regulation was c o n t r o l l e d by Hb(Alc) quantif i c a t i o n . The diagnosis of PNP was based on evaluation of r e f l e x status, motor f u n c t i o n , s e n s i t i v i t y f o r touch, p o s i t i o n , v i b r a t i o n , pain, and temperature. Measurement of n. s u r a l i s conduction v e l o c i t y was completed by evaluation of r e f r a c t o r y period as an e l e c t r o p h y s i o l o g i c a l correlate of sensory PNP. For t e s t i n g autonomic r e g u l a t i o n ECG-frequency and a r t e r i a l blood pressure were registered while patients were exerting a continuously repeated pressure with the r i g h t hand, expiring air against a resistance or during passive t i p p i n g manoeuvre from horizontal to v e r t i c a l p o s i t i o n . Evaluation of the data from c l i n i c a l neurologic state, n. s u r a l i s neurography, and autonomic r e g u l a t i o n , obtained by d i f f e r e n t authors under blind conditions, demonstrates inconsistency of the r e s u l t s of e i t h e r of the i n vestigated parameters. Involvement of the autonomic nervous system is not in every case combined with sensorymotor or neurographic f i n d i n g s and vice versa.
F266 THE VALUE OF DIFFERENT ELECTROPHYSIOLOGICALPROCEDURES IN THE DIAGNOSIS OF MULTIPLE SCLEROSIS. COMPARISONWITH OTHER LABORATORYTESTS IN 180 PATIENTS RINGELSTEIN,E.B., HACKE,W., ZEUMER,H., EIDEN,G.~ Department of Neurology, Technical High School, Goethestrasse 27-29, D- 51 Aachen, FRG In order to determine the diagnostic value of various approaches in patients with m u l t i p l e sclerosis (MS), the c l i n i c a l , e l e c t r o p h y s i o l o g i c a l (VEP, SSEP, OOR), neuroradiological (CT) and CSF-parameters were assessed and compared. The system of Confavreux et al (1980) (termed CON) was used to c l a s s i f y the patients according to the p r o b a b i l i t y of MS-diagnosis from a c l i n i c a l point of view. This system also considers the elevation IgG in CSF. I f a l l the above mentioned data were considered ( A l l ) the r a t i o of patients with d e f i n i t e diagnosis of MS increased considerably. Parameters were analyzed as to t h e i r cont r i b u t i o n to the r e l i a b i l i t y of MS-diagnosis. Thus, the most informative procedures could be defined. The conclusive r e s u l t s are summarized in the f o l l o wing table: Parameter R e l i a b i l i t y of MS-diagnosis ( r e l a t i v e frequency) definite probable possible CON 58% 27% 15% CON plus CT 69% 21% 10% CON plus complete electrophysiology 80% 14% 6% ALL 84% 10% 6% CON plus OOR 58% 28% 14% CON plus Medianus-SSEP 59% 28% 13% CON plus Suralis-SSEP 60% 27% 13% CON plus VEP 66% 21% 13%