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Pain syndromes in encephalomyelora-diculoneuritis
150 pressed for the 2 ms interval, requiring apparently much greater effort for estimation than only other interval. Table I. Significance of mutual differences among four
flashes threshold estimation Duration of flashes
C
=
>
20 ms : 20 ms : 20 ms: 10 ms: 10ms: 5 ms :
40 65 100 44 91 66
55 34 0 55 9 34
5 1 0 1 0 0
10 ms 5 ms 2 ms 5 ms 2ms 2 ms
Type of significance
The values in the body are expressed in %. However, no significant difference has been found for measurements taken at the instant of R wave and 400 ms later. As regards the changes of the actual heart rate during double pulse threshold estimation, it is important to consider the law of initial values at fist. It is not possible to expect acceleratory and/or deceleratory responses when already the pre-trial heart rate levels are higher or correspondingly low. It is extremely difficult to overcome this problem, e.g. to withhold the run, when heart rate level occurs outside a certain range. This approach does not consider some autonomic lability or greater intraindividual heart rate differences. For these reason we preferred to handle some preprocessed data, i.e. we registered always 10 seconds heart rate means obtained just prior and during threshold estimation. It is clear that the measurements of the above type are not contingent upon the phase of the heart cycle. Contrary to generally accepted procedure to test the speeding or slowing of the heart rate on perception, we looked, how the heart activity per se can be influenced by the increasing difficulty of the cognitive task. The answer, however, is not simple, as approximately in 30% only the expected increase in heart rate was observed. References
Barry, R.J. (1984) The evoked cardiac response under processing load. Physiol. Psychol. 12: 35-40. Cornsweet, T.N. (1962) The staircase-method in psy-
chophysics. Am. J. Psychol. 75: 485-491. In&a, M., Bohdaneckjr, Z., Radil, T. (1987) Tracking errors related to cardiac cycle : a new approach. Int. J. Psychophysiol. 5: 161-166. Lacey, J.I. (1967) Somatic response patterning and stress: Some revisions of activation theory. In: Appley M.H and Trumbull R. (Eds), Psychological Stress: Issues in Research. New York: Appleton-CenturyCrofts, 14-42. Radil, T., Sykova, E. (1977) On the possible role in neurons origine. Relationships between vegetative processes and reticular neurons activity (In Russian). Zhum. vys. nerv. deyat. 27: 322-323.
PAIN SYNDROMES IN ENCEPHALOMYELORADICULONEURITIS M. Bojar Department of Neurology, Pediatric Faculty, Charles University, Praha, Czechoslovakia Neurologists have a unique chance to diagnose and treat various pain states associated with numerous diseases of NS. The most challenging and enigmatic pain syndromes seem to be neuralgia and reflex sympathetic dystrophy. The pathogenesis of neuralgia has been explained by different theories targeted mostly at zosterneuralgia/Denny-Brown, 1944, Melzack, 1965/. A hypothesis of the leading role of local demyelination of inflamed or injured peripheral nerves that can combine with sprout out-growth, is promising. Changed metabolism of channel transporting system, evolution of new malfunctioning ectopic pacemakers discharging spontaneously or under the influence of circulating catecholamines are studies/ Devor, 1983/. Abnormal and spontaneous firing of peripheral nerves interfering with dysfunction of sympathetic spinal ganglia and impairment of spinal neuronal circuits often caused by inflammatory immune-mediated processes represent important clinical model of pain syndromes/ Sunderland, 1976/. Out of a group of 149 patients /79 F, 70 M. av.age 47 yrs./ treated for peripheral facial palsy / PFP/ and another group of 25 subjects/ 16 F, 9 M, av. age 43 yrs./ treated for zoster encephalomyeloradiculoneuritis/ H-3 EMN/ 33 cases of PFP of H-3 origin were diagnosed/
151 190/o/.Acute neuralgia of N.V. occurred in 24 persons /
14%/, persisting only in 5 cases/ 3%/ longer than 3 weeks. 7 patients /28%/ from the H-3 EMN group suffered from acute or subacute onset of post-herpetic pain. Typical neuralgia developed later and persisted in 3 cases / 120/o/.There was a typical CSF formula with proteinocytologic association, followed by long-lasting hyperproteinorhachy: positive titres of antibodies against H-3 in CSF were repeatedly detected - not rarely without herpes zoster eruptions. EMG study detected peripheral neuropathy, signs of axonal damage in all examined cases. EEG was abnormal in 54% of examined PFP patients and in more than 60% of EMN group, ENG was abnormal in 85% of both groups, EP were abnormal in about 40% of the subjects examined. These results proved multifocal impairment of NS. Corticosteroides, calcium entry blockers and acyclovir in severe cases were used. In pain syndromes amitriptyline, levopromazine, carbamazepine were combined with local anesthetics and transcutaneous nerve stimulation with good or moderate results. Clinical and laboratory data in H-3 group can be compared with data from a group of 78 patients/50 F, 28 M, av.age 43 yrs./ treated for Lyme neurolorreliosis. Symptoms of EMN were most marked in 35 cases/ 45%/. Patients suffered from excruciating pain, extremely variable and diffuse, with a very discrete neurological finding in the initial phase of the disease. Pain started often in the middle thoracic region imitating even surgical complications. 3 cases of burning feet syndrome were registered and many uncommon pain conditions remained unproperly diagnosed until CSF and ELISA tests were performed. The evaluation of unspecific neurological finding was complicated by frequent psychopathological symptoms imitating even hysteria. EEG/ 65% of abnormalities/ was useful, detecting impairment of temporal lobes or brain-stem. BAEP were abnormal in 40% of recordings and ENG in 90%. EMG detected 64% of abnormalities - signs of axonal neuropathy or radiculopathy were the most pronounced. Intensity and special quality of distressing painful dysesthesia and hypemlgesia exceeded other pain syndromes caused by other inflammatory affections of NS, even post-herpetic pain. Very good and quick therapeutical effect of high-dose of corticosteroides combined with penicillin or cephalosporin antibiotics was proved. Unbearable radicular burning pain disappeared after a few days cure though other symp-
toms might still progress. Histopathological studies of peripheral nerves detected vasculitis of peripheral perineurial vasa nervorum and severe angiopathic lesions of neural parenchyma/ Camponovo, 1986/, mild axonal loss with perivenular mononuclear infiltrates/ Halparin, 1987/. They can be explained by autoimmune mediated vasculitis and demyelinating lesions of NS. Post-herpetic neuralgia is supposed to be caused mainly by demyelinating lesions of thick myelinated A fibres whose number was found to be reduced in comparison with thin unmyelinated fibres - as a model of deafferentation pain/ Laurie, 1%6/. The importance of pathologic involvement of the dorsal root ganglia and peripheral nerves has been repeatedly stressed though the complexity of H-3 induced NS impairment has been neglected. The complex character of pain syndromes in borreliosis had been mentioned even before the definition of Lyme disease was published/ NeundUrfer, 1973/. Further comparison of clinical symptoms, electrophysiological, immunological and CSF studies in pain syndromes caused by persisting herpetic viruses and Borrelia burgdorferi is necessary to improve our knowledge of pathogenesis of postinflammatory pain conditions and their better management. References
1. Camponovo, F., Meier, C/1986/ Neuropathy of vasculitic origin in a case of Garin-Bujadoux-Bannwarth syndrome with positive borrelia antibody response. J. Neurol., 233:69-72 2. Denny-Brown, D. et al./1944/ Pathologic features of herpes zoster. A note on “geniculate herpes”. Arch. Neural. Psychiatry 51:216-231 3. Devor, M./1983/ Nerve pathophysiology and mechanisms of pain in causalgia. J. Auton. Nerv. Syst. 7:371-384 4. Halperin, J.J. et a1./1987/ Nervous system abnormalities in Lyme disease. Intl.Conference on Lyme disease and related disorders, N.Y. Acad. of Sciences, 1987 5. Lourie, H.,King, R.B./1%6/ Sensory and neurohistological correlates of cutaneous hyperpathia. Arch. Neurol. 14:313320 6. Melzack, R., Wall, P.D. Pain mechanisms: A new theory./ 1965/Science 150:97 l-979 7. Neundorfer, B./1973/ Differentiahypologie der
152 Polyneuritiden und Polyneuropathien. Springer Vrlg, Berlin, 25-58 8. Sunderland,S./1976/ Pain mechanisms in causalgia. J.Neurol. Neurosurg. Psychiatry 39:471-480
DIFFERENCES IN HABITUATION BETWEEN NEUROTIC PATIENTS AND NORMALS REFLECTED BY AUDITORY EVOKED POTENTIALS F. Bblsche Department of Pathophysiology, Medical Academy of Magdeburg, GDR The habituation was defined as a reduction of response magnitude after repeated stimulus application (Groves and Thomson, 1970) and applies to both overt behavioural and physiological responses such as EPs (Megela 1970). EP habituation to regular rhythmic presentation of the same stimulus has been reported frequently (Keidel and Spreng 1965, Rothman 1970). In these studies we measured the dimension of the amplitude reduction between the major negative (Nl) and positive (P2) peaks. Forty eight normal hearing adults ranging in age from 21 to 38 years participated in the study. The subjects were either healthy volunteers or neurotics. Two stimulus series consisting of identical 1000 Hz tones were applicated for the right and left ear. The tones were delivered monaurally with an intensity of 70 dl3 SL. EPs to these tones were recorded from the vertex with ipsilateral ear reference and grounded with a contralateral ear electrode. The tone series were divided in three parts with 35 stimuli which were separately averaged. In this way the short-term intrasession habituation (Shagass 1977) was provable and we could establish a comparison in the habituation between normals and neurotics.
DEPENDENCE OF MMN ON INTERSTIMULUS INTERVAL C. Biittcher, P. Ullsperger Dept. Psychophysiology, Central Institute of Occupational Medicine, Noldnerstr. 40/42 Berlin, G.D.R.
The mismatch negativity (MMN) discovered by NHaMnen et al. (1978) in auditory evoked brain potentials (AEP) is regarded as a fully automatic cerebral response to a stimulus physically deviating from the stimuli of the immediate past. NaWnen suggested that each auditory stimulus leaves a short-duration trace in the primary auditory cortex which represents the physical features of the eliciting stimulus and decays over 10 seconds. M&rtysalo and Nat&en (1987) tryed to determine the duration of the assumed neuronal representation exactly by varying the interstimulus interval (ISI) of a stimulus block. They suggested that a deviant stimulus can elicit a MMN only when the neuronal trace of the previous standard stimulus still exists. Presenting the stimuli with constant IS1 they found that a clear MMN was elicited by the deviant stimulus when the IS1 amounted to 1 or 2 seconds, but it was not present with IS1 of 4 and 8 seconds. They concluded that the duration of the neuronal trace was less than 4 seconds. The present investigation aimed in examination of MMN changes due to presentation of stimuli with randomized ISIS. Method
7 healthy volunteers participated in the investigation. Via loudspeaker two tones a so-called standard tone (1000 Hz) at a probability of 90%, and a deviant tone (1500 Hz) at a probability of 10% were presented to the subject. There were two experimental conditions: EXPI (reading) and EXPII (counting). For the reading task the subjects were instructed to read a book and to ignore the auditory stimuli. For the counting task the subjects were instructed to read the book and additionally to count the number of deviants and to report the count. The EEG was recorded from Fz and Cz with a linked ear reference (time constant: 2.5 2, upper frequency cut off 30 Hz). EEG periods starting 200 ms before and 800 ms after stimulus onset were averaged selectively for each IS1 and frequency. The MMN was evaluated by measuring the most negative peak in the different waveforms which were calculated by subtracting AEPs to standards from those to the deviants for corresponding ISI.
flashes threshold estimation Duration of flashes
C
=
>
20 ms : 20 ms : 20 ms: 10 ms: 10ms: 5 ms :
40 65 100 44 91 66
55 34 0 55 9 34
5 1 0 1 0 0
10 ms 5 ms 2 ms 5 ms 2ms 2 ms
Type of significance
The values in the body are expressed in %. However, no significant difference has been found for measurements taken at the instant of R wave and 400 ms later. As regards the changes of the actual heart rate during double pulse threshold estimation, it is important to consider the law of initial values at fist. It is not possible to expect acceleratory and/or deceleratory responses when already the pre-trial heart rate levels are higher or correspondingly low. It is extremely difficult to overcome this problem, e.g. to withhold the run, when heart rate level occurs outside a certain range. This approach does not consider some autonomic lability or greater intraindividual heart rate differences. For these reason we preferred to handle some preprocessed data, i.e. we registered always 10 seconds heart rate means obtained just prior and during threshold estimation. It is clear that the measurements of the above type are not contingent upon the phase of the heart cycle. Contrary to generally accepted procedure to test the speeding or slowing of the heart rate on perception, we looked, how the heart activity per se can be influenced by the increasing difficulty of the cognitive task. The answer, however, is not simple, as approximately in 30% only the expected increase in heart rate was observed. References
Barry, R.J. (1984) The evoked cardiac response under processing load. Physiol. Psychol. 12: 35-40. Cornsweet, T.N. (1962) The staircase-method in psy-
chophysics. Am. J. Psychol. 75: 485-491. In&a, M., Bohdaneckjr, Z., Radil, T. (1987) Tracking errors related to cardiac cycle : a new approach. Int. J. Psychophysiol. 5: 161-166. Lacey, J.I. (1967) Somatic response patterning and stress: Some revisions of activation theory. In: Appley M.H and Trumbull R. (Eds), Psychological Stress: Issues in Research. New York: Appleton-CenturyCrofts, 14-42. Radil, T., Sykova, E. (1977) On the possible role in neurons origine. Relationships between vegetative processes and reticular neurons activity (In Russian). Zhum. vys. nerv. deyat. 27: 322-323.
PAIN SYNDROMES IN ENCEPHALOMYELORADICULONEURITIS M. Bojar Department of Neurology, Pediatric Faculty, Charles University, Praha, Czechoslovakia Neurologists have a unique chance to diagnose and treat various pain states associated with numerous diseases of NS. The most challenging and enigmatic pain syndromes seem to be neuralgia and reflex sympathetic dystrophy. The pathogenesis of neuralgia has been explained by different theories targeted mostly at zosterneuralgia/Denny-Brown, 1944, Melzack, 1965/. A hypothesis of the leading role of local demyelination of inflamed or injured peripheral nerves that can combine with sprout out-growth, is promising. Changed metabolism of channel transporting system, evolution of new malfunctioning ectopic pacemakers discharging spontaneously or under the influence of circulating catecholamines are studies/ Devor, 1983/. Abnormal and spontaneous firing of peripheral nerves interfering with dysfunction of sympathetic spinal ganglia and impairment of spinal neuronal circuits often caused by inflammatory immune-mediated processes represent important clinical model of pain syndromes/ Sunderland, 1976/. Out of a group of 149 patients /79 F, 70 M. av.age 47 yrs./ treated for peripheral facial palsy / PFP/ and another group of 25 subjects/ 16 F, 9 M, av. age 43 yrs./ treated for zoster encephalomyeloradiculoneuritis/ H-3 EMN/ 33 cases of PFP of H-3 origin were diagnosed/
151 190/o/.Acute neuralgia of N.V. occurred in 24 persons /
14%/, persisting only in 5 cases/ 3%/ longer than 3 weeks. 7 patients /28%/ from the H-3 EMN group suffered from acute or subacute onset of post-herpetic pain. Typical neuralgia developed later and persisted in 3 cases / 120/o/.There was a typical CSF formula with proteinocytologic association, followed by long-lasting hyperproteinorhachy: positive titres of antibodies against H-3 in CSF were repeatedly detected - not rarely without herpes zoster eruptions. EMG study detected peripheral neuropathy, signs of axonal damage in all examined cases. EEG was abnormal in 54% of examined PFP patients and in more than 60% of EMN group, ENG was abnormal in 85% of both groups, EP were abnormal in about 40% of the subjects examined. These results proved multifocal impairment of NS. Corticosteroides, calcium entry blockers and acyclovir in severe cases were used. In pain syndromes amitriptyline, levopromazine, carbamazepine were combined with local anesthetics and transcutaneous nerve stimulation with good or moderate results. Clinical and laboratory data in H-3 group can be compared with data from a group of 78 patients/50 F, 28 M, av.age 43 yrs./ treated for Lyme neurolorreliosis. Symptoms of EMN were most marked in 35 cases/ 45%/. Patients suffered from excruciating pain, extremely variable and diffuse, with a very discrete neurological finding in the initial phase of the disease. Pain started often in the middle thoracic region imitating even surgical complications. 3 cases of burning feet syndrome were registered and many uncommon pain conditions remained unproperly diagnosed until CSF and ELISA tests were performed. The evaluation of unspecific neurological finding was complicated by frequent psychopathological symptoms imitating even hysteria. EEG/ 65% of abnormalities/ was useful, detecting impairment of temporal lobes or brain-stem. BAEP were abnormal in 40% of recordings and ENG in 90%. EMG detected 64% of abnormalities - signs of axonal neuropathy or radiculopathy were the most pronounced. Intensity and special quality of distressing painful dysesthesia and hypemlgesia exceeded other pain syndromes caused by other inflammatory affections of NS, even post-herpetic pain. Very good and quick therapeutical effect of high-dose of corticosteroides combined with penicillin or cephalosporin antibiotics was proved. Unbearable radicular burning pain disappeared after a few days cure though other symp-
toms might still progress. Histopathological studies of peripheral nerves detected vasculitis of peripheral perineurial vasa nervorum and severe angiopathic lesions of neural parenchyma/ Camponovo, 1986/, mild axonal loss with perivenular mononuclear infiltrates/ Halparin, 1987/. They can be explained by autoimmune mediated vasculitis and demyelinating lesions of NS. Post-herpetic neuralgia is supposed to be caused mainly by demyelinating lesions of thick myelinated A fibres whose number was found to be reduced in comparison with thin unmyelinated fibres - as a model of deafferentation pain/ Laurie, 1%6/. The importance of pathologic involvement of the dorsal root ganglia and peripheral nerves has been repeatedly stressed though the complexity of H-3 induced NS impairment has been neglected. The complex character of pain syndromes in borreliosis had been mentioned even before the definition of Lyme disease was published/ NeundUrfer, 1973/. Further comparison of clinical symptoms, electrophysiological, immunological and CSF studies in pain syndromes caused by persisting herpetic viruses and Borrelia burgdorferi is necessary to improve our knowledge of pathogenesis of postinflammatory pain conditions and their better management. References
1. Camponovo, F., Meier, C/1986/ Neuropathy of vasculitic origin in a case of Garin-Bujadoux-Bannwarth syndrome with positive borrelia antibody response. J. Neurol., 233:69-72 2. Denny-Brown, D. et al./1944/ Pathologic features of herpes zoster. A note on “geniculate herpes”. Arch. Neural. Psychiatry 51:216-231 3. Devor, M./1983/ Nerve pathophysiology and mechanisms of pain in causalgia. J. Auton. Nerv. Syst. 7:371-384 4. Halperin, J.J. et a1./1987/ Nervous system abnormalities in Lyme disease. Intl.Conference on Lyme disease and related disorders, N.Y. Acad. of Sciences, 1987 5. Lourie, H.,King, R.B./1%6/ Sensory and neurohistological correlates of cutaneous hyperpathia. Arch. Neurol. 14:313320 6. Melzack, R., Wall, P.D. Pain mechanisms: A new theory./ 1965/Science 150:97 l-979 7. Neundorfer, B./1973/ Differentiahypologie der
152 Polyneuritiden und Polyneuropathien. Springer Vrlg, Berlin, 25-58 8. Sunderland,S./1976/ Pain mechanisms in causalgia. J.Neurol. Neurosurg. Psychiatry 39:471-480
DIFFERENCES IN HABITUATION BETWEEN NEUROTIC PATIENTS AND NORMALS REFLECTED BY AUDITORY EVOKED POTENTIALS F. Bblsche Department of Pathophysiology, Medical Academy of Magdeburg, GDR The habituation was defined as a reduction of response magnitude after repeated stimulus application (Groves and Thomson, 1970) and applies to both overt behavioural and physiological responses such as EPs (Megela 1970). EP habituation to regular rhythmic presentation of the same stimulus has been reported frequently (Keidel and Spreng 1965, Rothman 1970). In these studies we measured the dimension of the amplitude reduction between the major negative (Nl) and positive (P2) peaks. Forty eight normal hearing adults ranging in age from 21 to 38 years participated in the study. The subjects were either healthy volunteers or neurotics. Two stimulus series consisting of identical 1000 Hz tones were applicated for the right and left ear. The tones were delivered monaurally with an intensity of 70 dl3 SL. EPs to these tones were recorded from the vertex with ipsilateral ear reference and grounded with a contralateral ear electrode. The tone series were divided in three parts with 35 stimuli which were separately averaged. In this way the short-term intrasession habituation (Shagass 1977) was provable and we could establish a comparison in the habituation between normals and neurotics.
DEPENDENCE OF MMN ON INTERSTIMULUS INTERVAL C. Biittcher, P. Ullsperger Dept. Psychophysiology, Central Institute of Occupational Medicine, Noldnerstr. 40/42 Berlin, G.D.R.
The mismatch negativity (MMN) discovered by NHaMnen et al. (1978) in auditory evoked brain potentials (AEP) is regarded as a fully automatic cerebral response to a stimulus physically deviating from the stimuli of the immediate past. NaWnen suggested that each auditory stimulus leaves a short-duration trace in the primary auditory cortex which represents the physical features of the eliciting stimulus and decays over 10 seconds. M&rtysalo and Nat&en (1987) tryed to determine the duration of the assumed neuronal representation exactly by varying the interstimulus interval (ISI) of a stimulus block. They suggested that a deviant stimulus can elicit a MMN only when the neuronal trace of the previous standard stimulus still exists. Presenting the stimuli with constant IS1 they found that a clear MMN was elicited by the deviant stimulus when the IS1 amounted to 1 or 2 seconds, but it was not present with IS1 of 4 and 8 seconds. They concluded that the duration of the neuronal trace was less than 4 seconds. The present investigation aimed in examination of MMN changes due to presentation of stimuli with randomized ISIS. Method
7 healthy volunteers participated in the investigation. Via loudspeaker two tones a so-called standard tone (1000 Hz) at a probability of 90%, and a deviant tone (1500 Hz) at a probability of 10% were presented to the subject. There were two experimental conditions: EXPI (reading) and EXPII (counting). For the reading task the subjects were instructed to read a book and to ignore the auditory stimuli. For the counting task the subjects were instructed to read the book and additionally to count the number of deviants and to report the count. The EEG was recorded from Fz and Cz with a linked ear reference (time constant: 2.5 2, upper frequency cut off 30 Hz). EEG periods starting 200 ms before and 800 ms after stimulus onset were averaged selectively for each IS1 and frequency. The MMN was evaluated by measuring the most negative peak in the different waveforms which were calculated by subtracting AEPs to standards from those to the deviants for corresponding ISI.