[Uterine leiomyosarcoma with subsequent pregnancy]. / Uterine Leiomyosarkome mit nachfolgender Schwangerschaft.

Leiomyosarcoma are malignant tumors showing smooth muscle differentiation, they are rare, representing only about 25 percent of all uterine sarcomas and mixed malignant tumors and slightly more than 1 percent of all corporeal malignant tumors. Usually they arise in postmenopausal women and are not known to be related to the known risk factors for endometrial carcinoma (nulliparity, obesity, diabetes mellitus, hypertension, etc.) or carcinosarcoma (prior radiation therapy). They may occur in uteri that also bear typical benign leiomyomas, but leiomyosarcoma rarely can be proven to have arisen in or from benign leiomyomas. We report on two premenopausal women with leiomyosarcoma--out of totally 31 cases in our clinic from 1975-1995 who got pregnant after surgical treatment preserving the uterus. The patients are alive without evidence of disease 3 and 6 years after surgical resection.

[The prognostic place of EEG in comparison with evoked potentials in severe hypoxic brain damage]. / Prognostischer Stellenwert des EEG im Vergleich zu evozierten Potentialen bei schwerer hypoxischer Hirnschädigung.

This retrospective study comprises 34 patients, who died due to the cerebral damage caused by severe anoxia, who were assessed by EEG and AEP or SEP on the same day and in whom at least one of these electrophysiological methods indicated a fatal prognosis. EEG-findings identified 76% of patients with fatal outcome, whereas SEP reliably predicted the outcome in 93% of patients, who died of the cerebral anoxia. In some patients centrally acting drugs made EEG-based but not SEP-based prognosis impossible. In some cases of fatal brain damage, however, only the EEG-findings as opposed to SEP-findings predicted the fatal outcome. Thus the combined assessment by EEG and SEP appears to be optimal in the assessment of an early prognosis. The BAEP were of less prognostic value than the EEG. BAEP findings indicating a fatal outcome were to be found mainly in final clinical stages with loss of brainstem function, whereas EEG as well as SEP identified a considerable number of fatal cases in spite of comparably favourable clinical findings. The evaluation of early electrophysiological testing done within the first 3 days after the anoxic event results in an identical estimation of the prognostic significance of EEG versus BAEP- or SEP-findings, respectively.

[Early prognosis in severe cranio-cerebral trauma using the Glasgow Coma Score and evoked potentials]. / Frühzeitige Prognose beim schweren Schädel-Hirn-Trauma mittels Glasgow-Koma-Score und evozierter Potentiale.

During 72 h following severe head injury, 103 patients in acute posttraumatic coma were assessed by clinical examinations (documented by Glasgow Coma Score) and brain stem auditory evoked potentials (BAEP) as well as short-latency somatosensory evoked potentials (SEP) following median-nerve stimulation. Patient outcomes were classified at 6 months or more according to the following categories: good recovery, severely disabled or vegetative, and brain dead. Patients who had died of systemic complications (pneumonia, septicemia, renal failure, etc.) were excluded from the study. The Glasgow Coma Score was reliable in forecasting a favorable outcome; all patients with a Score over 9 points had a good recovery. The Glasgow Coma Score was not reliable in predicting an unfavorable outcome, however; some patients with the lowest possible Glasgow Coma Score (3 points) at the early clinical examination survived with good recovery. The BAEPs were reliable predictors of an unfavorable outcome; the outcome was unfavorable when a missing wave V or more missing waves pointed toward a secondary brainstem lesion. Normal BAEPs were not reliable, however, in predicting a favorable outcome. SEP data served as a prognostic indicator of unfavorable as well as favorable outcomes. In summary, evoked potentials add valuable information to the clinical examination in assessing a patient's outcome after severe head injury.

[Early prognostic assessment using evoked potentials in severe craniocerebral trauma]. / Frühzeitige prognostische Aussage mittels evozierter Potentiale beim schweren Schädel-Hirn-Trauma.

103 patients in acute posttraumatic coma were assessed during 72 hours following severe head injury by clinical examinations (documented with a modified Glasgow-Coma-Score and a brain-stem-score and brainstem auditory evoked potentials (BAEP) as well as short latency somatosensory evoked potentials (SEP). Patient outcomes were classified at 6 months or more, according to the following categories: good recovery, severely disabled or vegetative, and brain dead. Patients who had died by systemic complications were excluded from the study. The Glasgow-Coma-Score was reliable in forecasting a favorable outcome, but tended to produce false-pessimistic predictions. The brainstemscore and the BAEPs were reliable predictors of an unfavorable but not a favorable outcome. SEP data however, performed well as a prognostic indicant in predicting an unfavorable as well as a favorable outcome. Using the BAEP, the amplitude ratio Wave V/Wave I is more sensitive to detect a lesion than the interpeak-latency Wave I-Wave V, and--using the SEP--the amplitude ratio N20/N13b (over C2) is more sensitive than the central conduction time (N13a (over C7)--N20).

Short-latency somatosensory evoked potentials in brain death.

Simultaneous recording of somatosensory evoked potentials to median nerve stimulation above the upper and lower neck in brain-dead patients revealed that all cervical responses were preserved in 10%, whereas a marked reduction in amplitude or even loss of N 13b at the level of the C2 spinous process was observed in 90%. Of the patients, 55% revealed an additional loss of N 13a, recorded at the level of the C7 spinous process; in 15% all cortical and spinal evoked potentials were missing, but Erb's point waves were still normal. These results suggest two different origins of the main negative waves (N 13a and N 13b), recorded above the upper and lower cervical spinal cord. N 13a (C7) is supposed to arise in the dorsal horn at the C6/7 level, N 13b (C2) in the cervicomedullary junction.

[Significance of somatosensory evoked potentials in determining brain death]. / Bedeutung der somatosensibel evozierten Potentiale (SEP) bei der Feststellung des Hirntodes.

Electrophysiological examinations are useful to confirm the clinical diagnosis of brain death and to substantiate the loss of brain function and of brain stem function. In addition to the EEG, which has been an useful ancillary test for many years to diagnose brain death, auditory and somatosensory evoked potentials are other electrophysiological techniques that give useful information on the assessment of brain death. In this study, short-latency somatosensory evoked potentials following median nerve stimulation were recorded in 20 patients who fulfilled the clinical criteria of brain death. The primary cortical responses N 20/P 25 recorded above the somatosensory cortex disappeared in all patients. Furthermore, except in two patients, there was a loss of the N 13 b component recorded above the spinous process C2 (N 13 b is assumed to originate in the cervicomedullary junction). Nine patients in whom brain death had occurred exhibited additionally changes of N 13 a - recorded above the spinous process C7 - a potential generated in the lower cervical cord. These data point to the occasional involvement of the cervical cord in the loss of function in patients in whom brain death had become manifest.

Somatosensory evoked potentials following median and tibial nerve stimulation in patients with Friedreich's ataxia.

The changes in evoked potentials following median and tibial nerve stimulation in nine patients with clinically defined Friedreich's ataxia are reported and discussed. The response originating in the brachial plexus (Erb's point potential) was absent or reduced in amplitude with no prolongation of peak latency, and the response generated in the cauda equina (N18) was absent in all cases. Conduction time from the brachial plexus to cervical spine and medulla oblongata was normal, whereas the central conduction time (N13a/N20, N13b/N20) was delayed. There was moderate to marked attenuation of the primary cortical response to median nerve stimulation. In one patient N20 disappeared during the course of the disease as opposed to the persisting subsequent negative wave, the latter thus simulating a very marked delay in the primary cortical response. Accordingly the cortical response to tibial nerve stimulation, which was only present in two patients and was markedly delayed, might represent a later potential with the primary response absent. The findings are consistent with neuropathological descriptions of a dying back neuropathy with primary axonal degeneration concerning the 1st order sensory neuron. In addition there is evidence either of delayed conduction in 2nd and 3rd order sensory neurones or of abnormal synaptic transmission.

[Significance of early acoustic evoked potentials in the diagnosis of brain death]. / Bedeutung der frühen akustisch evozierten Potentiale bei der Feststellung des Hirntodes.

Tests of early acoustic evoked potentials in 49 patients in whom clinical and EEG criteria indicated brain death demonstrated a bilateral loss of brainstem-generated components III to V in 12.6%, a loss of the components II-V in 16.8% and a loss of all early acoustic evoked potentials in 47.4%. This method, practicable in an intensive care unit, seems thus suitable for demonstrating loss of brainstem function as demanded for diagnosis of brain death.

[Evoked potentials. Indications and diagnostic significance]. / Evozierte potentiale. Indikationen und diagnostische Bedeutung.

Visual, auditory and somatosensory evoked potentials are useful in the detection and localization of demyelinating lesions, which mainly cause a slowing of conduction and therefore a latency increase in the evoked potential. Primarily amplitude reductions or loss of the response are seen in partial or complete impulse conduction blocks due to a tumor e.g. Acoustic nerve tumors can be detected by AEP, orbit tumors or processes of the chiasm by VEP and spinal cord tumors by SEP. The use of evoked potentials for the evaluation of ophthalmologic disorders, for audiometry in children and for monitoring head-injured patients with coma have become a valuable aid to the physician too.

[Generators of somatosensory evoked potentials following stimulation of nerves of the arm]. / Generatoren der somatosensorisch evozierten Potentiale nach Armnervenstimulation.

The cervical evoked potentials recorded above the 7th spinous process represent activity from the dorsal roots (N 11a) and the dorsal horn (N 13a), respectively. The upper neck responses are attributed to ascending activity in the dorsal column (N 11b) and the activation of the cuneate nucleus (N 13b). Scalp-leads from the contralateral sensory hand area using an Fz-reference consistently exhibit a sequence of components with successively more rostrally located generator sites: P 15 in or near the thalamus, N 20/P 25 in the primary sensory cortex and the following components in the parietal association fields (area 5 and 7).

Spinal and cortical evoked potentials following stimulation of the posterior tibial nerve in the diagnosis and localization of spinal cord diseases.

Evoked potentials from unilateral stimulation of the posterior tibial nerve at the ankle were recorded over the spinous processes L5, L1, C2 and Cz' in 30 normal subjects (Table Ia, b and c), 11 patients with multiple sclerosis (Table II) and 8 patients with a proven space-occupying spinal cord lesion (Table III). Delayed sensory conduction of both absolute latencies and side to side differences of P40 was seen in 91% of MS patients. Additional recording of spinal evoked potentials over L5, L1 and C2 did not significantly increase the percentage of abnormal responses. The spinal cord evoked responses therefore have their diagnostic importance in localizing the demyelinating process to the spinal or supraspinal section of the sensory pathway and in excluding peripherally delayed impulse conduction. The absolute latencies were within normal limits or only slightly delayed in the spinal tumor group. The interpeak latencies between the lumbar and the cervical or cortical responses showed less variability as compared to the absolute ones and revealed slight delays in some cases. Diagnostically more important seems the amplitude quotient between the cortical and the lumbar evoked potentials (P40/S response) which was below the normal range in two thirds of the tumor group patients.

Combined recordings of compound nerve action potentials and spinal cord evoked potentials in differential diagnosis of spinal root lesions.

Three cases are presented to demonstrate the diagnostic value of sensory neurography in combination with somatosensory evoked potentials in the diagnosis of proximally located neuropathy and its differentiation to centrally located demyelinating processes. Simultaneous recording of cortical and spinal evoked potentials, as well as peripheral nerve action potentials, revealed in two cases (herpes zoster, Guillain-Barré syndrome) a site of lesion at the spinal roots suggesting radiculitis and in one case (tick bite) a site of lesion central to the source of lumbar evoked potentials suggesting myelitis. In all cases almost complete recovery of sensory conduction velocities suggests a complete repair myelination not previously described.

Spinal somatosensory evoked potentials in cervical cord lesions.

Short-latency somatosensory evoked potentials (SEPs) to median and ulnar nerve stimulation were studied in 17 patients with cervical cord lesions of different sites and origins. Spinal cord lesions involving the 6th and 7th cervical segment led to an attenuation or loss of the cervical response after stimulation of the median nerve, whereas lesions at C8/D1 only affected the cervical response evoked by ulnar nerve stimulation. The third component of the neck-SEP (N13) was exclusively involved in some cases. More extensive lesions additionally abolished the second component (N11). Spinal cord lesions above the 6th cervical segment caused some dissociation of the simultaneously recorded responses at C7 and C2, with preserved responses at C7 and disturbed or absent evoked potentials at C2.

[Spinal and subcortical somatosensory evoked potentials after stimulation of the tibial nerve]. / Spinale und subkortikale somatosensorisch evozierte Potentiale nach Stimulation des N. Tibialis.

Evoked potentials in response to unilateral stimulation of the posterior tibial nerve at the ankle were recorded above the spinous processes L5, L1, C2, and at Cz' in 30 normal subjects. The "cauda-potential" recorded above L5 consists of two small negative peaks with a mean latency of 18 and 22.5 ms respectively, whereas the "cord-potential" recorded above L1 exhibited a peak latency of 21.2 ms and on average a three-times larger amplitude than the first of the two "cauda-potentials" (Fig. 1). Leads from the spinous process C2 revealed a sharp negative peak with a mean peak latency of 28.8 ms (N 30). Scalp recordings with a midfrontal (Fz-) reference inconsistently showed 1-2 small waves (P31, N33) prior to the primary cortical response (P40). Recordings with an ear- or non-cephalic reference consistently showed a large positive deflection (P30) which corresponded in latency with the simultaneously recorded cervical response (N30) and was followed by a distinct negative potential (N33) (Fig. 2a and b). Average latencies and amplitudes of the different spinal and subcortical evoked potentials (Tables 1 and 2), as well as the diagnostically more important interpeak-intervals, amplitude relations, and side-differences of latencies and amplitudes (Tables 3 and 4) were calculated. The diagnostic significance of these parameters will be shown in selected cases with spinal cord pathology.

Short-latency somatosensory evoked potentials to median nerve stimulation: components N 13--P 13, N 14--P 14, P 15, P 16 and P 18 with different recording methods.

Comparative recordings of short-latency somatosensory evoked potentials with midfrontal (Fz), ear and non-cephalic reference electrodes were obtained in 12 normal subjects to define the site of the generators of the different components and the spatial distribution and interference of the different components recorded at the neck and scalp. Such investigations provide the basis for identical investigations in patients with focal lesions of the central nervous system. The N 13 recorded from the neck (C2-Fz) and the inconsistently recorded component N 14 were quite similar in latency to the far-field potentials P 13 and P 14 recorded at the scalp (C3', C4'--ear or hand). The component P 15 was clearly visible only in scalp-Fz leads and occurred 0.2--0.9 ms (mean 0.5 ms) later than P 14 in ear or hand reference recordings. This is evidence against the identity of these two components proposed by others. In a larger group of 48 subjects, using an exclusive Fz-reference lead, normal values were established of the components P 15, P 16 and P 18, as well as their scalp distribution.