Clinical Neuroscience

[POSSIBLE ROLE OF THE BASAL GANGLIA IN THE GENERATION OF THE N30 POTENTIAL OF THE MEDIAN NERVE SOMATOSENSORY EVOKED POTENTIALS]

BENICZKY Sándor, NAGY Helga, VARGA Edina, VÖRÖS Erika, KÉRI Szabolcs, VÉCSEI László

SEPTEMBER 30, 2007

Clinical Neuroscience - 2007;60(09-10)

[Background and purpose - The origin and afferentation of the frontal N30 component of the median nerve somatosensory evoked potentials (SEPs) have not yet been fully elucidated. The aim of this study was to assess the possible selective impairment of the N30 component in patients with lacunar infarcts of the basal ganglia as compared to patients with lacunar infarctions sparing the basal ganglia and to a group of healthy subjects. Methods - Median nerve SEPs were measured in ten patients with lacunar infarctions of the brain (but no cortical atrophy or leukoaraiosis) and 13 healthy volunteers. Four patients had lacunar infarctions affecting the basal ganglia and 6 patients had lesions affecting other structures. Results - In two patients with lesions affecting the head of the caudate nucleus, there was no identifiable N30 component on the affected side. In one patient with bilateral lesions of the globus pallidus, the amplitude of the N30 component was significantly reduced. In one patient with lesion of the tail of the caudate nucleus, the N30 component was unaffected. The amplitude of the N30 component was also reduced in two patients with frontal subcortical white matter lesions. In all the other subjects, we recorded normal N30 components on both sides. Conclusion - Our results further support the importance of the basal ganglia, especially the head of the caudate nucleus in the generation of the N30 component of the median nerve SEPs.]

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[Systemic lupus erythematosus is a frequent autoimmune disease, affecting several organs, including the brain, spinal cord and nerves. Cerebral vasculitis, transverse myelitis and polyneuropathy are the most common neurological manifestations. We report a case of a 46 years old woman who suffered incomplete transverse myelitis in her age of 44. After 2 years the second relapse presented with arthralgias, painful paraesthesias and weakness of the lower limbs. Neurological signs suggested involvement of the central and the peripheral nervous system. Based upon clinical and laboratory findings systemic lupus erythematosus was diagnosed. Magnetic resonance imaging revealed two hyperintense lesions on T2 weighted scans within the cervical spinal cord. The brain scan was normal. Protein content was slightly elevated in the cerebrospinal fluid, with normal cell count. Electrophysiological examinations diagnosed a subacute sensory-motor axonal polyneuropathy. On methylprednisolone treatment her condition improved. Simultaneous development of central and peripheral lesions of the nervous system in cases with systemic lupus erythematosus may lead to a challenge to establish the diagnosis.]

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[This article deals with the effect of antiepileptic drugs on mood when applied in epiletic patients. The author points that depressive symptoms occur significantly more frequently in epilepsy and there are more common factor in the mechanism of action of the antiepileptic and antidepressive agents. The relevant literature is surprisingly poor. Primary and large analysis regarding affective disorders coexisting with epilepsy is still lacking. From this aspect some antiepileptic drugs have not been investigated at all. The consequences of the papers originates from indirect sources like adverse events profiles of the study drugs or from psychometric tests performed for avoiding exclusion criteria of psychological nature. On the other hand the paper deals also with the difficulties of such kind of investigations concerning the classification of depressive signs presenting with epilepsy, special considerations of inclusion of appropriate patients and particular limits of the measuring and follow-up of the observed effect. As the result of the detailed analysis of the literature the author recommends lamotrigine, carbamazepine and oxcarbazepine as first choice antiepileptic drug for epileptic patients suffering from depressive disorder, too. On the contrary, phenobarbital, topiramate and vigabatrin are able to worsen the affective symptoms. Aimed, randomized, controlled studies are necessary for recognizing the whole spectrum of psychotropic effects of antiepileptic drugs and for their successful and individually tailored application in patients in their comorbide states. Author calls the attention for the importance of the treatment of depressive states frequently occurring in epileptic patients. These symptoms modify the compliance of the patients and are able to influence even the epileptic process itself.]

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[Although still a controversial management option, radiosurgery of intracranial cavernomas has become increasingly popular world-wide during the last decade. Microsurgery is a safe and effective treatment for symptomatic hemispheric cavernomas. However, the indication for microsurgical resection of deep eloquent cavernomas is relatively limited even in experienced hands. The importance of radiosurgery has recently been appreciated in parallel with increasing positive experiences both in terms of effectiveness and safety, especially for cases high risk for surgical resection, in the brainstem, thalamus and basal ganglia. While radiosurgery was earlier indicated mainly for surgically inaccessible lesions that had bled multiple times, a more proactive policy has recently become more accepted. In our opinion preventive treatment with the low morbidity radiosurgery serves the patients’ interest especially for deep eloquent lesions that had bled not more than once, due to the cumulative morbidity of repeated hemorrhages. Despite our increasing knowledge on natural history, there is currently no available treatment algorithm for cavernomas. Arguments for all three treatment modalities (observation, microsurgery and radiosurgery) are established, but their indication criteria are yet to be defined. It is time to organize a prospective population based data collection in Hungary, which appears to be the most realistic way to clarify indication criteria.]

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[Background and purpose - Radiosurgery is an increasingly popular treatment option especially for deep eloquent intracerebral cavernomas that are often too risky for surgical removal, but their re-bleed carries significant risk for persisting neurological deficit. Gamma-radiation based radiosurgery has been being available since 2007 in Hungary in Debrecen. Our aim is to summarize our experience accumulated during the first five years of treatment and to compare it to the international experience. Patient selection and methods - We retrospectively analyzed 51 cavernomas in 45 patients treated between 2008 and 2012 in terms of localization, natural history, and the effect of radiosurgery on re-bleed risk and epilepsy, and its side effects. Results - We treated 26.5% deep eloquent (brainstem, thalamic/basal ganglia) and 72.5% superficial hemispheric cavernomas. The median presentation age was 25 years (13-60) for deep, and 45 years (6-67) for superficial cavernomas. They were treated median of 1 year after presentation. 64.5% of deep cavernomas bled before treatment, the annual risk of first hemorrhage was 2%/lesion, re-bleed risk 21.7%, with 44% persisting morbidity. 13.5% of superficial cavernomas bled prior to treatment, the risk of first bleed was 0.3%, there was no re-bleed, and 35% caused epilepsy. We used GammaART-6000TM rotating gamma system for treatment, marginal dose was 14 Gy (10-16), and treatment volume 1.38-1.53 cm3. Re-bleed risk of deep eloquent lesions fell to 4% during the first two years after treatment and to 0% thereafter, and no hemorrhage occurred from superficial lesions after treatment. Persisting morbidity in deep lesions came from adverse radiation effect in 7% and from re-bleed in 7%, and there was no persisting side effect in superficial cavernomas. 87.5% of cases of epilepsy resistant to medical therapy improved. Radiological regression was found in 37.5% and progression in 2% after treatment. Conclusions - Radiosurgery of cavernomas is safe and effective. Early preventive treatment for deep cavernomas carrying high surgical risk is justified. Moreover, for superficial lesions that are surgically easily accessible radiosurgery also appears to be an attractive alternative.]

Clinical Neuroscience

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