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Auditory brainstem responses (ABRs) have proved to be significantly related to outcome, both in severe head injury and brain hemorrhage. Nevertheless, the usefulness of ABR is limited by the anatomic extent of the investigated pathways. The combined use of ABRs and somatosensory evoked potentials (SEPs) improves the outcome prediction in comparison to the use of only one modality. It mainly decreases the rate of false negatives, since patients with severe hemispheric damage sparing the brain stem may have a poor outcome despite normal ABRs. The use of motor evoked potentials (MEPs) from magnetic transcranial stimulation is also significantly related to outcome: it appears to be far superior to the clinical evaluation of motor responses, while the combined use of MEPs and SEPs gives a new opportunity of checking sensorimotor dysfunction. ABRs and SEPs may also be useful tools in the confirmation of brain death, the kernel of which is the assessment of brainstem death: they allow to check lemniscal pathways, which cannot be properly evaluated by clinical examination, and provide an objective confirmation of absence of brain stem activity.

Four hundred and thirty-nine carotid endarterectomies (CEAs) with routine use of patchgraft angioplasty were performed in 375 patients; the indwelling shunt was used only in patients showing clamp-related EEG abnormalities. Five patients showed EEG abnormalities just after head positioning, which reversed after removal of head hyperextension; three cases suffered EEG flattening due to severe bradycardia or cardiac arrest before carotid clamping, which promptly reversed after treatment. Clamp-related EEG abnormalities appeared in 106 operations (24.2%) and all reversed after the insertion of the indwelling shunt; patients with occlusion of the contralateral internal carotid artery showed a 68.8% rate of EEG clamp-related changes. The short term follow-up (one month after the operation) showed six minor strokes with complete recovery (1.37%), one intraoperative stroke (0.23%), three delayed major strokes (0.69%) and three neurological deaths (0.69%). The long-term follow-up over an average of 42 months showed a 3.7% rate of relevant neurological complications (ie permanent deficits + death) and a 3.16% rate significant restenosis or occlusion of the operated carotid artery. Our results show that the routine use of EEG monitoring and patch-graft angioplasty allow to perform CEAs with a very high degree of safety, improving the clinical course of the disease.

The aim of this study is to evaluate whether SEP spatial mapping can improve outcome prediction in comparison to the conventional SEP recordings. Twenty patients comatose as a result of head injury or cerebral vascular disorders were submitted to 19-channel SEP mapping from median nerve stimulation. SEP recording were performed within the 4th hospital day in 18 cases and over one month from the insult in the remaining two. Nine patients (45%) showed a good recovery or a mild disability, 3 (15%) a severe disability and the rest (40%) died or remained in a vegetative state. Five patients (28%) had bilaterally normal SEP, 5 (28%) the absence of both parietal N20 and frontal N30, while the others (44%) had a dissociation N20/N30 (namely, preserved N20 with absent N30). The SEP mapping was significantly related to the outcome (P = 0.0087) and improved the outcome prediction in comparison to the conventional SEP recordings, allowing to check the presence of frontal N30: in patients with bilaterally present N20 the outcome appeared to depend upon the N30. SEP mapping proved to be a far superior prognostic indicator than the Glasgow Coma Scale. In 3 patients with midline shift on CT scan an abnormal spatial distribution of N20 was disclosed by SEP mapping. Our preliminary results suggest that SEP mapping may improve the assessment of comatose patients in comparison to the use of parietal derivations only.

From March 1980 to July 1988 a consecutive series of 256 patients (p.) underwent 301 carotid endarterectomy + patch with routine use of continuous intraoperative EEG monitoring and selective use of an intraluminal shunt (IS) for the presence of an atherosclerotic plaque concerning the internal carotid artery (ICA). Patients were divided in two groups: the first (42 p.) marked by contralateral ICA occlusion, the second (214 p.) without contralateral ICA occlusion (259 CEA). Immediate peroperative, long term and global (immediate and long term) outcomes were prospectively and comparatively studied. A temporary IS was inserted in 27 p. (64%) of the group I and in 38 p. (14%) of the group II. Immediate permanent postoperative neurological deficit occurred in 1 p. of group I (2.38%) and in 2 p. (0.9%) in group II. Immediate postoperative mortality was 0% and 0.9% in group I and II respectively. All p. had neurological valuation and Echo-Doppler of operated ICA and of the contralateral ICA every 6 months (middle follow-up 44 months). New neurological symptoms compared in 5.8% of p. of group I and in 5.23% of p. of group II with a stroke rate of 0% and 2.32% respectively. There were 2 restenosis of operated ICA, both of them in p. of group I, that underwent reoperation. In the two groups the principal causes of deaths were myocardial infarct and cancer; in the group I no death was due to stroke versus 1.86% in the group II.

15 patients with chronic progressive Multiple Sclerosis were treated with Hyperbaric Oxygen Therapy at 2.0 atmospheres absolute for a total of 20 daily exposures followed by 2 exposures every month. The treatment was carried out for a 24 months follow-up. No objective benefit resulted from Hyperbaric Oxygen Therapy at the completion of the study while a subjective improvement in bladder control was reported in the short and in the long-term follow-up by 8 and by 5 patients respectively. No significant variations in the electrophysiological results were observed after the first 20 consecutive exposures. It is concluded from this trial that a long-term Hyperbaric Oxygen Treatment cannot moderate the progression of Multiple Sclerosis. However, an improvement in the quality of life can be obtained in some patients resulting from a better control of bladder function.

Normal and thymectomised rabbits been have immunized by means of a thymic extract emulsified with Freund's Complete Adjuvant. The experiment was conducted over a three month period, in order to reproduce an experimental model of chronic myasthenia. During this period immunological, electromyographic and histologic studies were undertaken. Typical findings of partial neuromuscular block were invariably obtained from all the non thymectomized animals, while such signs were constantly absent both in non-treated control rabbits and in the immunized thymectomized ones. This neuromuscular block was intermittent. The compromised neuromuscular conduction was associated to an histological pattern of autoimmune myopathy. Evidence was put on antibodies directed against the thymus, muscular and nervous tissue. The results indicate the important role of the thymus gland both in altering conduction at the neuromuscular junction level and causing histopathologic muscle lesions.

From March 1980 to March 1987, 217 consecutive patients underwent 252 carotid revascularisations with routine use of continuous EEG monitoring and selective use of an intraluminal shunt for symptomatic (70%) or asymptomatic (30%) internal carotid artery (ICA) atherosclerotic stenosis. All carotid endarterectomies were routinely performed with a patch graft angioplasty. None of the patients suffered permanent or transient neurological deficits in the immediate postoperative period and none of them died. There was an 0.8% stroke rate and 0.4% mortality rate in the early postoperative course. Neurological assessment, Doppler and Echo doppler sonography of both the operated and the contralateral ICA was performed every 6 months. One-hundred and twenty-one patients (142 carotid revascularisations) operated on up to December 31st 1985 were reassessed in July 1986. The mean follow-up time was 35 months (range: 6 months to 6 years). New neurological symptoms were present in 7.4% of the patients; 2.5% of patients developed a stroke and 8.9% showed progression of stenosis in the contralateral ICA. One patient had a common carotid artery stenosis 2 years after surgery. Re-stenosis of the ICA was found in two patients who underwent re-operation without difficulty. The late mortality was 21.4% (11.9% of the overall series). In only two patients (7.6%) was stroke the cause of death.

From March 1980 to March 1987, at the Department of Vascular Surgery of the University of Padua, 217 patients underwent 252 carotid revascularizations with routine use of an intraluminal shunt (IS) for symptomatic (70%) or asymptomatic (30%) internal carotid artery (ICA) atherosclerotic stenosis. All carotid endarterectomies (CEs) were routinely performed with patch graft angioplasty to prevent restenosis. In the immediate post-operative period, no patient presented permanent or transient neurological deficits; no patient died. In the early post-operative course there was a 0.9% (2 patients) stroke rate and 0.4% (1 patient) mortality rate. These results suggest that the selective use of the IS on the basis of EEG changes is able to reduce the perioperative morbidity and mortality to nearly zero.

The EEG pattern of diffused low-voltage non-reacting fast activity is exceptional in comatose patients. The authors report on clinical observations, CT scan and neurophysiological findings in one case showing this EEG pattern after a severe head injury. In serial EEG recording it is shown a progressive shift from fast activity towards the alpha and theta bands. The presence of abnormal auditory brainstem responses and of CT scan signs of brainstem lesion suggest that this peculiar EEG pattern may be due to a brainstem lesion.

The short latency evoked potentials, allowing to assess the brain stem's function, can supply useful information in the diagnosis of Brain Death (BD). 15 BD patients were submitted to the auditory brain stem response (ABR); in 7 cases somatosensory evoked potentials from the medial nerve (SEP) were also recorded. The ABR was absent in 11 cases (73.3%), while in 3 cases only the I wave was present (20%); in one case the low-voltage I-V waves were present. Regarding the SEP, in 3 cases (42.9%) only the N9-N13 and P9-P13 waves were present, while in another 3 cases (42.9%) a N13/P13 dissociation was observable. In the remaining case, which presented a still reproducible I-V interval, the SEP was normal, thus excluding the diagnosis of BD. The ABR and the SEP, which are not roughly influenced by general anaesthetics and sedatives, are thus helpful in diagnosing BD. The SEP seems able to supply useful information more frequently than the ABR, but their combined use can guarantee maximum security of excluding false positives.

From March 1980 to July 1986 at the Department of Vascular Surgery of the University of Padua, 182 patients underwent 210 carotid revascularizations for atherosclerotic stenosis involving the carotid bifurcation (28 operations were bilateral). Carotid endarterectomies (CE) and patch graft angioplasty totalled 192 (166 patients); an enlarging patch graft angioplasty of the internal carotid artery (ICA) without CE was performed in 14 cases (13 patients); in the remaining four surgical procedures (3 patients), for technical reasons prohibiting CE, the operation consisted of a great saphenous vein bypass between a donor vessel and the ICA distal to the lesion. The preoperative symptoms in 182 patients were as follows: TIAs (98 cases, 54%), non-hemispheric symptoms (21 cases (12%) and fixed stroke or TIAIR (10 cases, 5%). Fifty-three patients (29%) were asymptomatic. In all cases, continuous EEG monitoring was employed. The operation was performed without a temporary intraluminal shunt in the patients showing tolerance to carotid clamping. The protection of the shunt was required only in patients with EEG changes (47 cases). The arteriotomy was routinely closed with a PTFE patch graft angioplasty. Early results of the operation were excellent: none of the patients presented permanent or transient neurological deficits in the immediate postoperative period and none of them died. All patients were reassessed with C.W. Doppler sonography and Duplex scanning in the postoperative period. In all cases, the success of the operation was demonstrated. Longterm follow-up (6-72 months, mean follow-up: 35 months) was done in 121 patients (142 operations): 107 patients were completely asymptomatic, 5 remained stable or slightly improved the preoperative status. Five patients had a new or recurrent TIAs, 3 suffered a stroke, one showed a recurrence of non-hemispheric symptoms. With the exception of two patients suffering a stroke, all had a second arteriography but none of these patients showed extracranial lesions. Two patients presented an asymptomatic restenosis of the ICA. Eight patients (8.8%) revealed a significant evolution of the disease of the contralateral unoperated ICA.(ABSTRACT TRUNCATED AT 400 WORDS)

The outcome is reported in 62 children with severe head injuries following a road traffic accident. All patients were comatose for at least 6 h; all patients were graded using the Glasgow Coma Score (GCS) or the Children Coma Score (CCS). Fifty-four patients were comatose immediately after injury, 8 after a lucid interval. Thirty patients had isolated head injuries and 32 had associated injuries, either long bone fractures or rupture of an abdominal organ. Additional information concerning main brainstem reflexes, posture and respiration was included in the study. The overall mortality was 32%. The goal of the study was to identify those clinical features available soon after injury which are important indicators of treatment and outcome.

19 ALS patients were submitted to motor evoked potentials (MEP) and F-wave from thenar muscles. Somatosensory evoked potentials (SEP) from median nerve were recorded as well in 16 patients. MEP were bilaterally absent in 4 patients (21%) and monolaterally absent in 6 patients (3.6%). Among patients with recordable waves, MEP and F-wave were significantly delayed. Their upper motor neuron conduction time was clearly abnormal only in one case. In SEP recordings the N9-N13 was significantly delayed, but the N13-N20 was normal. Four patients showed a combined sensory-motor dysfunction (increase of both N19-N13 interval and F-wave latency).