The combination of neuronavigation with transcranial magnetic stimulation for treatment of opercular gliomas of the dominant brain hemisphere.

OBJECTIVE: The objective of this study is to investigate the application of transcranial magnetic stimulation combined with neuronavigation for preoperative mapping of the language area in neurosurgical interventions on the opercular area of the dominant hemisphere. METHODS: Five patients were operated upon gliomas in the opercular area. For localization of the speech area a transcranial magnetic stimulator MEDTRONIC-MagPro was used. BrainLAB-VectorVision Neuronavigation system was utilized for precise planning of the operative approach. RESULTS: Gross total resection was achieved in all patients. Three-month postoperative follow-up was done. Three of the patients had a transient postoperative motor aphasia which resolved within 1 month. CONCLUSION: This method is useful for preoperative localization of the speech area, as well as preoperative planning of the operative approach and intra-operative planning of the direction of brain retraction and operative corridor.

New molecular knowledge towards the trigemino-cardiac reflex as a cerebral oxygen-conserving reflex.

The trigemino-cardiac reflex (TCR) represents the most powerful of the autonomous reflexes and is a subphenomenon in the group of the so-called "oxygen-conserving reflexes". Within seconds after the initiation of such a reflex, there is a powerful and differentiated activation of the sympathetic system with subsequent elevation in regional cerebral blood flow (CBF), with no changes in the cerebral metabolic rate of oxygen (CMRO2) or in the cerebral metabolic rate of glucose (CMRglc). Such an increase in regional CBF without a change of CMRO2 or CMRglc provides the brain with oxygen rapidly and efficiently. Features of the reflex have been discovered during skull base surgery, mediating reflex protection projects via currently undefined pathways from the rostral ventrolateral medulla oblongata to the upper brainstem and/or thalamus, which finally engage a small population of neurons in the cortex. This cortical center appears to be dedicated to transduce a neuronal signal reflexively into cerebral vasodilatation and synchronization of electrocortical activity; a fact that seems to be unique among autonomous reflexes. Sympathetic excitation is mediated by cortical-spinal projection to spinal preganglionic sympathetic neurons, whereas bradycardia is mediated via projections to cardiovagal motor medullary neurons. The integrated reflex response serves to redistribute blood from viscera to the brain in response to a challenge to cerebral metabolism, but seems also to initiate a preconditioning mechanism. Previous studies showed a great variability in the human TCR response, in special to external stimuli and individual factors. The TCR gives, therefore, not only new insights into novel therapeutic options for a range of disorders characterized by neuronal death, but also into the cortical and molecular organization of the brain.

Neurosurgery and elderly: analysis through the years.

The aging of the population in westernized countries constitutes an important issue for the health systems struggling with limited resources and increasing costs. Morbidity and mortality rates reported for neurosurgical procedures in the elderly vary widely. The lack of data on risk benefit ratios may result in challenging clinical decisions in this expanding group of patients. The aim of this paper is to analyze the elderly patients cohort undergoing neurosurgical procedures and any trend variations over time. The medical records of elderly patients (defined as an individual of 70 years of age and over) admitted to the Neurosurgical and Neuro-ICU Departments of a major University Hospital in Paris over a 25-year period were retrospectively reviewed. The analysis included: (1) number of admissions, (2) percentage of surgically treated patients, (3) type of procedures performed, (4) length of hospital stay, and (5) mortality. The analysis showed a progressive and significant increase in the proportion of elderly presenting for neurosurgical elective and/or emergency procedures over the last 25 years. The number of procedures on patients over 70 years of age increased significantly whereas the mortality dropped. Though the length of hospital stay was reduced, it remained significantly higher than the average stay. The types of procedures also changed over time with more craniotomies and endovascular procedures being performed. Age should not be considered as a contraindication for complex procedures in neurosurgery. However, downstream structures for postoperative elderly patients must be further developed to reduce the mean hospital stay in neurosurgical departments because this trend is likely to continue to grow.

[Characteristics and prognosis of visual deficit caused by parasellar meningiomas].

UNLABELLED: Meningiomas are the most common slow growing tumors of the central nervous system which arise from the arachnoid cells. One certain group of them--tuberculum sellae (TS), cavernous sinus (CS), anterior clinoid (AC), and planum sphenoidale (PS) meningiomas, a group often called "parasellar", present with monocular or binocular visual deterioration, which is often unrecognized by patients until visual loss is severe and the tumor has reached a significant size. AIM: To describes the type of visual deficit, severity of the symptoms and surgical treatment of tumors with the above mentioned localization. MATERIAL AND METHODS: During the period 2003-2007 year, 93 patients (31 man, 62 women) diagnosed with meningiomas of the TS (31 cases), CS (16 cases), AC (21 cases), PS (17 cases), (see text) - 8, were diagnosed and operated on in the Department of Neurosurgery, University Hospital "St. Ivan Rilsky", Sofia, Bulgaria. Retrospective analysis was done. RESULTS: Age at diagnosis ranged from 12 to 74 years, but the majority of cases were in the 5th and 6th decade of life. Localization of was: TS 33%, CS 17%, AC 24%, PS 18% and with more than one area affected in 8 %. The most common symptom was slowly progressing loss of monocular visual acuity (81% of cases). 68% of patients presented with already severely deteriorated vision (0.1-0). Neuro-ophthalmological examination (see text) the patients. Computed tomography and magnetic resonance imaging were the main diagnostic methods. "Gross" total resection was achieved in 62%, subtotal in 12%, partial in 26% of the cases. There was early improvement in 57% of the patients. Death due to cardio-respiratory insufficiency occurred in one case. CONCLUSION: the progressive monocular visual deficit is often the first clinical symptom of the parasellar menigiomas. The early diagnosis is important for the success of surgery. Close collaboration between different specialists (ophthalmologists, neurologist and neurosurgeons) is essential for treatment of these tumors and prevention of the visual deterioration.

[Orbital lymphoma].

INTRODUCTION: Orbital lymphomas are neoplasms with increasing incidence in recent years in immunocompromised, as well as immunocompetent patients, which defines their social importance. AIM: To describe and analyze the experience of the University hospital "'Sv. Ivan Rilski" with the treatment of this pathology for the period 1997-2008. MATERIAL AND METHODS: Fourteen patients (8 females, 6 males - 13 primary orbital lymphomas, 1 systemic lymphoma). Mean age at diagnosis was 65.6 years (from 50 to 80 years). In 2/3 of the patients the lesion was localized in left eye, without a case with bilateral orbital involvement. Seven cases the diagnosis was made 6 months from the onset of symptoms, 5 cases - 1 year and 2 cases - more than one year. The most common clinical symptoms were exophthalmus (12 case), tumor or bulging mass of the eyelid - 8, diplopy - 6, decreased visual acuity - 5. Intraconal localization of the tumor was in 6 cases, extraconal - 2. intra-extraconal - 6. The diagnosis was made by neuro-ophthalmologist and precised with the aid of CT and MRI. All the patients were operated on with the following approaches - fronto-orbital - 9 cases, lateral - 3, anterior orbitotomy (without bone resection) - 2 cases. In six cases "'gross total" resection was achieved, in the rest of the cases the resection was partial. On histological examination, a high grade lymphoma was established in 2 cases with primary orbital lymphoma and one case with systemic lymphoma. All other cases were diagnosed as low-grade B-call small lymphocytic non-Hodgkin's lymphoma. Long-term survival (over 5 years) was observed in 4 cases with primary lymphoma, whereas the patient with systemic form of the disease died 10 months after the operation.