[Hereditary cerebral cavernous malformations: analysis of 12 families]

Familial (hereditary) cerebral cavernous malformations (CCM) are rare disorders, they have autosomal-dominant type of inheritance. We report 12 families of non-Hispanic descent in which 54 typical CCM were discovered. In 8 families CCM were identified in 2 generations, in 2 - in 3 generations. 46 lesions were supratentorial, 8 - subtentorial. Multiple lesions were present in 67% of cases. Manifestation was observed in 24 persons, including seizures in 17 and hemorrhage in 7. In 9 of 10 families onset of symptoms was earlier with every next generation. In one patient asymptomatic parietal CCM was associated with symptomatic posterior fossa AVM and cutaneous angioma. On the follow-up MRI revealed no new lesions. Surgical treatment was performed in 14 cases: in 13 patients 15 CCM were removed, and 1 patient underwent third ventriculostomy. The paper discusses evaluation and management of families with symptomatic and asymptomatic types of disease, trends and perspectives of further investigations.

[Surgical approaches to thalamic tumors]

The paper summarizes the results of surgical treatment of patients with thalamic tumors of different topographic variants. Since 1985 till 2010 127 patients were operated, 147 direct surgical interventions were performed. Repeated surgeries were required due to partial resection of a tumor or recurrence. In most cases resection of tumors was performed via transcallosal (48%) and occipital interhemispheric (29%) approaches. Less common approaches included transcortical (frontal, temporal, parietal) (14%), pterional through lateral and basal parts of Sylvian fissure (6%) and subtentorial supracerebellar (3%). Selection of approach is based on topographic features of tumor within thalamus, direction of its growth and relations with adjacent structures (internal capsule, brainstem, hypothalamus, ventricular system). Each approach has its own advantages and drawbacks which are highlighted in the paper.

[Neurosurgery: achievements and challenges]

Neurosurgery is one of the most dynamic and fast-developing medical sciences aimed at studying a wide range of diseases and lesions of the nervous system with constant improvement of methods of their diagnosis and surgical treatment. With the routine clinical use of computed tomography, positron emission tomography, magnetic resonance imaging the possibilities of revealing structural, metabolic and functional changes in the brain in different types of pathology have significantly enlarged. Today, methods of neurovisualization are widely used for preoperative modeling and intraoperative navigation. Also, these methods permit to study the fundamental aspects of brain functioning in health and pathology at the organ, tissue, cellular and molecular levels. In the last decades, the spectrum of neurosurgical methods including microsurgical, endoscopic, stereotactic, radiosurgical, reconstructive and other technologies was extended and diver-

[Compression cervical spine cord injury in patients with posterior cranial fossa tumors operated on in the sitting position: two cases with different outcomes]

The paper describes two cases of posterior cranial fossa pathology, operated on in the sitting position on the operating table. In one case, symptoms of cervical spine injury caused by undiagnosed preoperative cervical spine pathology emerged in a female patient in the early postoperative period. In the other case, cervical spine pathology was diagnosed before surgery and evoked potentials were monitored to prevent possible cervical spine injury in the sitting position during an operation.

[Paradoxical dynamics in the values of bispectral index for bilateral registration in a patient during parastem tumor removal (a clinical case)]

The paper describes an unusual clinical case. During a neurosurgical operation (removal of parastem tumor (neuroma) on the right side), bilateral registration of the bispectal index (BSI) in order to monitor a hypnotic component of anesthesia showed that the tumor removal stage was marked by a paradoxical reaction of the BSI as an increase in its values up to 70-80% (corresponds to the patient's emergence) on the right, ipsilaterally, with the preserved low BSI values on the left--30-40%. Possible explanations of the observed are considered.

[Linear accelerator-based stereotactic radiotherapy and radiosurgery in treatment of neurosurgical patients]

Radiation methods are essential in management of certain types of neurooncological, neurovascular and functional brain pathology. Application of stereotactic technique of irradiation allows sufficient damaging impact on target (tumor, AVM, functional structures) and maximal protection of surrounding brain tissues. Indications to radiation treatment of intracranial lesions are expanding with evolution of stereotactic methods. The paper deals with the first experience of linear accelerator-based treatment of patients with intracranial neurosurgical pathology in this country. Techniques of stereotactic radiotherapy (SRT) and radiosurgery (SRS), indications to SRS and SRT in different modes of fractioning are described in details. Additionally specific complications, radiation reactions and feasibility of neurovisualization in diagnosis of radiation-induced brain damage are discussed.

[Green fluorescent protein has no effect on blastocyst development in C57BL/6-Tg(ACTB-EGFP)1Osb/J mice]

The changes in the state of long-term culture of blastocysts derived from female C57BL/6 mice after crossing with C57BL/6-Tg(ACTB-EGFP)1Osb/J males with a green fluorescent protein transgene EGFP on chromosome 15 were studied. Possible causes of different culture results were analyzed: the preservation of undifferentiated cells as dense clusters in the inner cell mass or their differentiation into extraembryonic endoderm. Comparison of the events going in blastocysts with the -/- or -/EGFP genotypes demonstrated that the GFP presence has no effect on cell processes. This allows us to use embryonic material from this mouse line in experiments that require long-term vital observation of embryonic cells.

[Topographic variants of cranial chordomas]

The objective of this study was to investigate variants of localization of cranial chordomas. We examined 220 patients treated in Burdenko Neurosurgical Institute (Moscow, Russia) since 1985 till 2007. In the vast majority of cases (93%) tumors were localized in sellar region (34%), clivus (32%) and craniovertebral junction (27%). As addition to previously suggested classifications we distinguish special group of craniofacial chordomas (5%). Although chordomas are theoretically midline tumors, according to our data in many cases (40%) they may be lateralized.

[Positional damage of the sciatic nerve during neurosurgical intervention into the posterior cranial fossa in the sitting position]

The paper describes a rare case of severe, but reversible bilateral damage to the sciatic nerve (compression neuropathy) in a patient with Blumenbach's clivus meningioma developing during 12-hour operation removing the tumor in the patient's sitting position on the operating table. The etiology and prevention of this complication are discussed.

[A case of early postoperative posttransfusion-associated lung injury (TRALI) in a female patient with giant intracranial meningioma and massive intraoperative blood loss]

The paper describes a case of the relatively rare complication transfusion-associated lung injury (TRALI) in the early postoperative period in a female patient who has experienced intraoperative massive blood loss and blood transfusion. It also considers the causes of this complication, its clinical symptoms and differential diagnosis, as well as a package of therapeutic measures and possible lines of prevention.

[Surgical treatment of skull base chordomas]

The paper analyses the series of 220 observations of patients with cranial chordomas operated in Burdenko Neusurgical Institute (Moscow, Russia) since 1984 till 2007. Tumors were localized in sellar region (34.1%), clival region (32.3%), craniovertebral junction (27.3%); craniofacial chordomas were observed in 5.9% of cases, ectopias (without any connection with clivus and sphenoocipital junction)--in 0.5%. In most cases transnasal, retrosigmoid and pterional approaches were used for excision of the tumor. The paper emphasizes the problem of selection of surgical tactics, early and delayed postoperative results. 5-year survival rate was 62%, 10-year survival--47%.

[Vascular decompression in the treatment of trigeminal neuralgia]

Trigeminal neuralgia is characterized by unilateral paroxysmal facial pain. Patients often describe this pain as "the most sever pain one can suffer". Vascular compression of trigeminal nerve root directly near brainstem by artery or vein is considered the main etiology of trigeminal neuralgia. Consequently, basic pathogenetic treatment is vascular decompression of trigeminal nerve root that allows to eliminate the cause of pain. 140 patients with trigeminal neuralgia were operated in Burdenko Neurosurgical Institute since 1998 to 2007. Pain relief after surgery was observed in 96% of cases. There was no mortality in our series, overall delayed complication rate was less than 1,5%. The article deals with clinical presentation of classic trigeminal neuralgia, evaluation of the role of MRI in diagnosis of this disease and description of surgical types of arterial and venous root compression. Authors demonstrated that high effectiveness of vascular decompression depends on correct clinical diagnosis.

[Pharmacoresistant temporal epilepsy: surgical treatment and analysis of factors influencing on its results]

An objective of the study is an analysis of the results of surgical treatment and influence of resection volume on the treatment outcome. Sixty-four patients, aged 7-46 years, with an epileptic focus in a temporal lobe have been studied. Patients have been stratified into 2 groups. The first group included 55 patients with epileptogenic lesions of a temporal lobe (monoregional lesions) and the second one--9 patients who, along with the lesion of one temporal lobe, had the signs of lesions in other brain areas (multiregional lesions). In the group of patients with monoregional lesions, a resection of the affected area has been performed. In other patients, the techniques of resection of frontal-medial temporal lobe regions within the scope of the area of steady epileptiform activity have been used. The results have been assessed with the modified Engel scale: class I--an absence of clinically manifested seizures (auras are possible); class II--seizures that do not impact quality of life; class III--a decrease of seizures frequency by more than 80%; class IV--an absence of substantial improvement. In the monoregional lesions, the satisfactory results (I-II classes) were observed in 39 patients (74%), including outcomes of class I (28 patients). In other 16 cases outcomes of classes III and IV were observed. In the multiregional lesions and cryptogenic (possibly symptomatic) partial epilepsy, outcomes of classes III and IV were observed in all patients, regardless of the resection volume. In conclusion, the highest efficacy with regard to frequency and severity of seizures is achieved by resections including the whole area of visualized lesion and border-line area of steady epileptic activity, the identification of which demands the intrasurgery neurophysiologic study. In the extensive and multiregional lesions, the resection surgery confined to one temporal lobe has low effect.

[First experience with a Gamma-knife unit used for radiosurgical treatment for intracranial space-occupying lesions]

A Gamma-Knife unit that is currently the gold standard in radiosurgery was first used in clinical practice in 1968. The essence of the radiosurgical treatment is to apply the stereotactic technique to high-precision irradiation of small intracranial targets by narrow beams of ionizing radiation from external sources. Three hundred and six patients with various intracranial diseases (137 with malignant tumors, 136 with benign tumors, and 33 patients with vascular diseases) underwent radiosurgery on a Gamma-Knife unit for over 1.5 years, from May 2005 to October 2006. A total of 329 irradiation sessions were performed. By summing up the first results, it can be noted that stereotactic radiosurgery using a Gamma-Knife unit is an effective and rather safe technique in the treatment of patients with various types of intracranial pathology, which maintains the high quality of life, reduces the likelihood of development of different neurological disorders after treatment and avoids the risk of operative complications. The possibility of performing outpatient treatment for a diversity of diseases without mandatory anesthesiological, ICU, and rehabilitative maintenance, determines the potential economic efficiency of this treatment.

[Results of surgical treatment in patients with neurocytomas of the brain]

Central neurocytoma (CN) is a rare brain neoplasm which is characterized by certain clinical, radiological, and morphological characteristics. This tumor was first described in 1982 by J. Hassoun et al. who found neurosecretory granules and microtubules while microscopically studying 2 patients with oligodendrogliomas of lateral ventricles and concluded that these neoplasms were of neuronal origin. Materials and methods. In 1992 to 2004, a total of 84 patients diagnosed as having CN were treated at the Academician N. N. Burdenko Research Institute of Neurosurgery, Russian Academy of Medical Sciences. In most cases, the tumor showed a clinical picture as elevated intracranial pressure that was detected in 80 (more than 90%) cases. In this series, all neurocytomas were located in the ventricles, mainly in the pellucid septal region; tumor infiltration of the lateral ventricular ependyma and medullary substance invasion into the region of the thalamus and corpus callosum. Computed tomographic scans displayed central neurocytomas as space-occupying lesions of mixed (heterogeneous) density, which frequently contained single and multiple petrificates and cysts. TI-weighted magnetic resonance imaging (MRI) indicated that in most cases (n=56, 66%), the intensity of a signal from the tumor was mixed and similar to that of the white matter of the brain. These masses were characterized by the presence of tumor structural cysts that were better visualized on T2-weighted tomograms. The tumor was removed in 83 cases; 2 out of them had previously undergone stereotactic biopsy (STB). STB was performed alone in one case. Transcallous, transcortical-through-premotor-area, combined, and transcallous-transcortical approaches were applied when the neurocytomas were removed. Results. Total removal of a tumor (when its remains were not visualized by postoperative MRI) was achieved in 11 (13%) patients. Its subtotal removal was accomplished in 48 (58%) patients. Partial removal was done in 24 (29%) patients. In the early postoperative period after tumor removal, there was a worse health status along with a transient progression of cerebral and focal symptoms in most patients with CN. The magnitude, pattern, and duration of these changes differed. Conclusion. The long (from several months to several years) history of the disease and young age (14 to 59 years) are typical of patients with CN. The tumors are located intraventricularly, more commonly along the midline, and they have well-defined X-ray signs: these are well-circumscribed tumors of heterogeneous density, which frequently contain single and/or multiple cysts and petrificates; there is a moderate contrast enhancement. The basic way of improving the results of treatment in patients with CN is the latter's early diagnosis and surgery when the tumor is locally advanced within the ventricular system.

[Giant cavernous malformation of the cerebellum in a baby]

The paper presents a rare case of successful removal of giant cavernous malformation of the cerebellum in a baby. It describes the specific features of differential diagnosis of space-occupying lesions of the posterior cranial fossa in infants in detail.