Clinical Neuroscience

[Intraoperativ electrophysiological monitoring during neurosurgery on eloquent structures]

FEKETE Gábor, NOVÁK László, ERÕSS Loránd, FABÓ Dániel, BOGNÁR László

JANUARY 30, 2015

Clinical Neuroscience - 2015;68(01-02)

[Objective - We summarize our experiences on intraoperative electrophysiological monitoring during neurosurgical procedures on eloquent neuronal structures. Patients, methods - Sixty patients were enrolled retrospectively in our study with pathologies involving eloquent neuronal structures. They were operated between May 2011. and March 2012. at the University of Debrecen, Department of Neurosurgery and at the National Institute of Neurosciences. Patients underwent standard preoperative examinations due to the primary pathology. In all cases we used intraoperative electrophysiological monitoring. We had 22 cases with cranial nerve monitoring, 10 cases with cauda monitoring, 16 cases with motor system monitoring, six cases with complex spinal cord monitoring, three degenerative spine reconstructions and 3 awake surgeries. Results - We found that with the use of intraoperative electrophysiology we could make these neurosurgical procedures safer, and were able to optimize the extent of resection in the cases of oncological pathologies. Conclusions - Our experiences as well as the international literature suggests that in certain high risk neurosurgical procedures intraoperative electrophysiology is indispensible for safe and optimally extended operation.]



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Clinical Neuroscience


RAJNA Péter, TAJTI János

Clinical Neuroscience

[Extending therapeutic possibilities in relapsing-remitting multiple sclerosis: dimethyl fumarate]


[Dimethyl fumarate (DMF) is a novel oral therapy that has recently been approved for the treatment of relapsing- remitting multiple sclerosis (RRMS). Dimethyl fumarate shows anti-inflammatory and cytoprotective properties that are thought to be mediated primarily via activation of the nuclear factor (erythroid-derived 2)-like 2 - Nrf2 transcriptional pathway, which up-regulates the genes involved in the cellular response to oxidative stress. The drug was evaluated in 2 large, randomized, double-blind, multicentric, multinational, 2-year, phase III clinical trials. The DEFINE and CONFIRM trials, conducted with over 2600 adult patients suffering from RRMS, unequivocally confirmed the efficacy of DMF (2×240 mg daily) in reducing the annualized relapse rate (ARR) and reducing the proportion of patients with MS relapse at 2 years. Significantly reduced sustained disability progression was observed with the drug versus placebo in DEFINE, while the same tendency was seen in CONFIRM. The MRI results of the studies were also convincing: DMF significantly reduced the number of new/enlarging T2-hyperintense lesions and the number of Gd-enhancing lesions compared to placebo. Dimethyl fumarate was generally well tolerated and no safety concern has been raised. Adverse events that occurred most frequently included flushing and gastrointestinal events. The long- term efficacy and tolerability of dimethyl fumarate is currently being investigated in the ENDORSE trial, with interim results demonstrating the same results as the two previous studies. In conclusion, although further, mostly comparative data are needed to fully establish the relative efficacy and tolerability of dimethyl fumarate compared with other therapies, dimethyl-fumarate is a valuable addition to the therapeutic options available for RRMS.]

Clinical Neuroscience

[Role of modified open-door laminoplasty in the treatment of multilevel cervical spinal stenosis: a retrospective analysis of 43 cases]


[Background and purpose - Symptomatic degenerative multilevel cervical spinal stenosis - beside other methods - is often treated using the open-door laminoplasty. This procedure aims to decompress the spinal cord and preserve the stability of the cervical spine. The efficiency and safety of the method was proved by numerous Japanese and American studies, also the technique related complications are well known. We treated 43 patients with symptomatic multilevel cervical spine stenosis using the open-door laminoplasty as a surgical procedure of choice in the National Institute of Clinical Neurosciences between 2009 and 2012. In this article we analyse our results and the related literature is discussed. Methods - Symptomatic patients with a minimum of three-segment cervical spine stenosis and radiologically proved myelopathy or with electrophisiologically verified subclinical myelopathy were selected for laminoplasty. Patients in whom cervical kyphosis was present were operated on using laminectomy and posterior fusion. Postoperative control CT, MRI and/or X-ray images were made after the surgery and at six weeks, three, six and 12 months after the operation and in the same time neurological evaluation was performed. The modified Japanase Orthopaedic Association (mJOA) scale value was assigned to patients preoperatively, six weeks, three, six and 12 months after the operation. The statistical difference between the groups of data was tested by chi square test. Results - The average follow-up time was 27 months (minimum seven, maximum 42). According to the mJOA scale, 26 patient’s condition (61%) improved, in 13 cases (30%) remained unchanged, and in one case (2%) we detected neurological deterioration. We lost three patients during the follow up period. The median of mJOA preoperatively was 12 (minimum eight, maximum 18), while six week postoperative mJOA was 14 (minimum 10, maximum 17). Three, six and 12 months mean value of mJOA was 14 which shows that the improvement in patients’ condition remained stable at one year after surgery. The difference was statistically significant (p<0.05). The canal’s average anteroposterior diameter on CT was 8.29±0.92 mm at the level of C III, while after the operation we measured 15.16±1.02 mm; 7.54±0.62 mm at the level of C IV before, and 15.29±0.2 mm after; 9.05±0.48 mm at the level of C V before and 17.23±0.4 mm after the surgery. The differences proved to be significant (p=0.0001). Conclusion - According to our experiences the modified open-door laminoplasty is an efficient and safe method for the treatment of symptomatic multilevel cervical spinal stenosis.]

Clinical Neuroscience

[The efficacy of lacosamide in relation to antiepileptic drug history. Clinical experiences in adult partial epilepsy]


[Objective - A retrospective study in adult partial epilepsy on the efficacy of lacosamide in relation to previous antiepileptic drug experiences. Method - We analysed 3-65 months’ data on epilepsy-care of 43 pharmacoresistant partial epilepsy patients treated with lacosamide. Further analysis of antiepileptic drug history was carried out in strictly selected subgroups of patients with good and poor therapeutic response to lacosamide (10 and 9 patients, respectively) for 2-10 years long retrospective follow up. Patients - Adult patients with partial-onset seizures had been treated previously with three or more lifetime antiepileptic drugs without permanent success. Results - Six patients (14%) were seizure free, eleven patients (25%) have experienced important improvement (their seizure-frequency decreased by at least 50%) for more than 12 months. Fourteen patients (32%) improved for less than 6 months and then have relapsed; and add-on lacosamide proved ineffective in 12 patients (28%). Those selected 10 patients successfully treated with lacosamide (seizure free for at least six months) favourably responded to carbamazepine or oxcarbazepine earlier and levetiracetam was ineffective or even caused worsening. The selected lacosamide-unresponsive nine patients responded unfavourably to carbamazepine or oxcarbazepine earlier. Fifteen patients (35%) suffered side effects as dizziness or sleepiness, in 11 of them lacosamide was combined with a „traditional” sodium-channal blocker antiepileptic drug. Conclusion - Lacosamide is an effective add-on antiepileptic drug in difficult-to treat adult partial epilepsy patients. Our data suggest that good lacosamide response may be expected in those patients who reacted favourably to „traditional” sodium-channel blocker carabamazepine or oxcarbazepine earlier.]

Clinical Neuroscience

[Assessment of severity and time course of critical illness neuropathy in septic patients: a prospective observational study]


[Objective - In this prospective observational study we investigated electrophysiological alterations in the early phase of critical illness and correlated electrophysiological findings with the clinical picture and outcome. Methods - We enrolled 21 critically ill surgical patients having ≥12 Acute Physiology and Chronic Health Evaluation (APACHE) II scores on admission. Routine non-invasive bilateral electroneurography (ENG) examination of median and ulnar nerves was done on five consecutive days starting in two days after admission. Then weekly follow-up was performed. Motor and sensory nerve conduction indices were calculated and correlated with APACHE II and Simplified Acute Physiology Score II severity scores. Results - On the first examination 18/21 patients had >20% reduction in the motor and sensory nerve conduction indices. Severity score systems showed significant negative correlation with the daily change of CMAP and SNAP amplitudes and calculated nerve conduction indices (Spearman’s correlation, p<0,001). Mortality was higher in the patients with worse admission ENG and/or stagnant electrophysiological status or declining tendency in the first week. Conclusions - Electrophysiological alterations appeared soon after the development of critical illness. Early phase alterations showed a strong correlation with patients’ general condition and more severe electrophysiological alterations predisposed to higher mortality. In several cases early alterations proved to be reversible. ]

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Clinical Oncology

[Treatments of brain tumors in adults – an up-date]

BAGÓ Attila György

[Maximal safe resection is the fi rst step in the complex neurooncological therapy of adult brain tumors. Surgical management of brain tumors, including the surgical innovations (neuronavigation, intraoperative imaging, awake craniotomy, intraoperative electrophysiology) providing more radical resection with the safe preservation of neurological functions will be presented. In case of malignancy the surgery is followed by radiation and chemotherapy. In this review we describe the postoperative adjuvant therapeutical modatilites available for primary and metastatic tumors, emphasizing the modern chemotherapy of high grade gliomas and stereotactic radiosurgery of brain metastases. As a conclusion we summerize the guidelines and modalities for the most common adult brain tumors, according to histological type and grade.]

Clinical Neuroscience

[The significance of high-resolution ultrasonography in the diagnosis of peripheral nerve disorders]


[High resolution ultrasonography is an emerging technique for the investigation of peripheral nerves and is increasingly used worldwide in the diagnosis of peripheral nerve disorders, however, until now it is not widespread in Hungary. According to the literature this method is especially useful in entrapment neuropathies, traumatic peripheral nerve injuries, tumors of the peripheral nerves and sonographically guided interventions. Ultrasonography allows precise morphological analysis and quantitative measurements of the nerves providing useful complementary information to electrodiagnostic data. In entrapment neuropathies ultrasound shows nerve swelling mainly proximal to the sites of compression and a focal change of echotexture. On longitudinal scan, an abrupt caliber change and spindle-like swelling of the compressed nerve segment can be seen. Evaluation of the anatomical background and visualisation of the postoperative and posttraumatic changes provide useful information for planning of the therapy. Ultrasound may be of significant help in localizing the pathological nerve segment when it is at an electrophysiologically inaccessible site or when substantial secondary axonal loss precludes precise electrophysiological localization and it might even show pathological changes when nerve conduction studies are normal. Contrary to electrophysiological investigation ultrasonography might discover neurotmesis in the akute phase of traumatic nerve injuries indicating the necessity of surgical intervention. We provide a summary of the main indications and further application areas of this method.]

Clinical Neuroscience



[Introduction - While it is several decades ago that electrophysiological studies in the early stages after an ischaemic stroke revealed spontaneous activity in the affected muscles, today few data are available on the peripheral changes in later stages after a cerebrovascular event. The aim of this study was to detect electrophysiological signs that could indicate changes at the motor unit level occurring within a longer post-stroke period. Patients and methods - Forty-four patients who had developed hemiparesis after an ischaemic stroke in the area of the middle cerebral artery were involved in the study. Motor and sensory nerve conduction studies and electromyography were carried out on each side on six nerves and in five muscles respectively. Values between the affected and unaffected side were compared by statistical methods. Results - In patients with hemiparesis present for less then nine months, low M wave amplitudes, fibrillation potentials and an increased number of complex motor unit potentials were found on the affected side; in patients with symptoms present for more then nine months the mean duration and size index of the motor unit potentials in the paretic abductor digiti minimi muscle were increased. These data suggest a process of neurogenic type. The signs of distal axonal damage observed in the early period after stroke have been replaced later by chronic neurogenic changes. These changes could be the consequence of spinal motor neuron damage and axonal transport disturbance due to the loss of supraspinal trophic inputs. Conclusion - The correlation between the extent of electrophysiological changes and of the central motor deficit of the patient indicates the importance of delaying this process by appropriate rehabilitation procedures.]

Clinical Neuroscience

[Selective dorsal rhizotomy in the treatment of spasticity - Hungarian experiences ]

FEKETE Gábor, NOVÁK László, VEKERDY-NAGY Zsuzsanna, BOGNÁR László

[Objective - We summarize our initial experiences with selective dorsal rhizotomy that we introduced in Hungary to manage the spasticity of patients with cerebral palsy. Patients and methods - Thirty spastic patients were enrolled in our study. All of the patients were operated between July 2014 and June 2015. We performed selective dorsal rhizotomy from a single-level approach at the level of conus medullaris in all cases, with electrophysiological control. Results - We could perform the surgery in all cases safely. Adverse events related either to damage of neurological structures, or to surgery did not occur. The planned rehabilitation courses before and after the operations are in progress in all cases. Conclusion - Selective dorsal rhizotomy is an irreversible surgical intervention to treat spasticity. With sufficient experience and electrophysiological control it can be performed safely, and the early results are promising. ]

Hungarian Radiology

[Intraoperative intracranial ultrasound imaging in neurosurgery]

DOBAI József Gábor, GYARMATI János, IFJ. SZÉKELY György, CSÉCSEI György István

[Diagnostic ultrasound imaging started in the 1940s. Up to the present it underwent on radical changes. Article briefly reviews the major steps of the development of ultrasound technique in neurosurgery, and possibilities of applications of different ultrasound methods in neurosurgery are described. Authors discuss their experiences with Hawk 2102 ultrasound system used in intraoperative procedures in 113 cases. Data compared with the literature. Conclusions are that use of intraoperative ultrasound in neurosurgery is modern and simple and it has various application fields. Intracranial lesions are well localized with its use, so the risk of operations decreases. Main disadvantages that ultrasound imaging requires bony trepanation and special transducers are needed for different lesions.]