[Surgical resection in combination with stereotaxic cryodestruction in patients with supratentorial gliomas in functionally significant areas of the brain: possibilities of using combined surgical treatment and its results].

A combined method of surgical treatment of glial tumors of the brain is proposed for decreasing risk of complications. The method includes microsurgical ablation of the main volume of the neoplasm and stereotaxic cryodestruction of the residual part of the tumor. Combined surgical treatment was used in 12 patients. The results obtained show that the proposed method elevates the efficacy of surgical method, facilitates increased indices of survival rate and maintenance of quality of life of the patients at the tolerant level.

[Technique of stereotactic cryodestruction in management of patients with cerebral gliomas].

Aim of the study was to evaluate the safety and efficiency of stereotactic cryodestruction of supratentorial astrocytomas that were located deeply in the brain and/or within eloquent areas.We examined 74 patients aged 18-64 years with supratentorial gliomas of different grade located in deep or eloquent brain areas. All the patients underwent stereotactically guided cryodestruction of the tumor. The survival rate was evaluated by the Kaplan-Meier method. The chi-square method was used for comparative analysis of results of this study with available data from the literature. For the analysis of the prognostic importance of various factors the Cox proportional hazards model was applied. The average survival period was 12.4 months for glioblastoma (control group--6.4 months, p=0.04), and 46.9 months for anaplastic astrocytoma (control group--18 months, p=0.006). For patients with fibrillar-protoplastic astrocytoma the 5-year survival rate was 95.7%. The frequencies of complications did not exceed those of the routine surgical interventions in patients with brain tumors. We found that stereotactic cryodestruction as well the Karnofsky performance score were statistically reliable prognostic factors (p=0.0377 and p=0.0006, respectively), while the extent of cryodestruction and the residual tumor mass did not influence the survival rate. Stereotactic cryodestruction is a safe surgical procedure, which results in statistically significant improvement of survival in patients with supratentorial gliomas located within deep and/or eloquent areas of brain.

[Cryosurgical method in functional stereotactic neurosurgery].

Method of cryodestruction of deep subcortical structures is used in functional stereotactic operations in patients with chronic progressing diseases of the central nervous system. The PAH device produces cooling the tissues in the target point of the brain to -70 degrees C, which allows to obtain the destruction focus with volume 0.2 or 1 cm3. The source of cooling in the apparatus is solid cryodestruction carbonic acid. The method was used in 352 patients. The results of operations showed high degree of repeatability of geometric parameters of the obtained foci in the target structures, as well as the absence of the general and pronounced local tissue reaction to the cryodestruction foci. There was low percentage of hemorrhagic and infectious complications.

[Functional stereotaxy with magnetic resonance tomographic guidance]. / Funktsional'naia stereotaksiia s magnitno-rezonansno-tomograficheskim navedeniem.

The paper summarizes experience with stereotactic operations by magnetic resonance imaging data by using a Russian OREOL stereotactic manipulator. It describes methods of preoperative preparation of patients by employing diagnostic magnetic resonance tomographs. A number of points of the procedure for identification and localization of deep target structures from magnetic resonance images in parkinsonism, temporal epilepsy and some mental disorders.

Differential approach to psychosurgery of obsessive disorders.

One of the most frequent indications of psychosurgical treatment is incurable obsessions. Up to now, capsulotomy or cingulotomy has been preferred. In our opinion, the variety of obsessive conditions require a more thorough approach to the selection of interbrain targets. Forty-seven patients with pure obsessive-compulsive disorders as well as disorders connected with depressions, epileptic syndrome, schizophreniform state and Gilles de la Tourette's syndrome with extremely severe resistance to medical therapy were examined. Eighteen patients were operated on. Surgical treatment is permissible only in cases fulfilling the three following criteria: (1) clinicopsychopathological permissibility (duration of disease, resistance to medication, psychopathological status); (2) physiological permissibility (the presence of a brain target, defining the psychopathological status), and (3) technical permissibility (the availability of proper stereotactic, imaging, electrophysiological and other apparatus necessary to carry out the surgical treatment). One supposes that the outcome of surgical treatment is determined by all three criteria. For the purpose of improving the efficiency of stereotactic treatment, a number of methods of surgical treatment depending on the psychopathological status are suggested. For example, in case of comorbidity of obsession with the epileptiform syndrome, we suggest cingulotomy (capsulotomy) and amygdalotomy; in case of comorbidity with depression we suggest cingulotomy and innominatotomy. The long-term observation of the outcome of stereotactic treatment covers a period from 2 up to 9 years.

[Status and developmental prospects of the medical proton channel in the synchrocyclotron in Gatchina]. / Sostoianie i perspektivy razvitiia meditsinskogo protonnogo trakta na sinkhrotsiklotrone v Gatchine.

The medical proton beam on the synchrocyclotron in Gatchina modernized in 1980, is characterized by a simplicity of the beam adjustment that amounts to standard operations, the time of adjustment reduced considerably. The optical scheme ensures a good reproducibility of all the beam parameters from session to session. A large "zone of convergence" makes it possible to select a necessary irradiation field size with the diameter from 3 to 10 mm. A new medical complex with a 2-room premises for irradiation is envisaged on the basis of the "second beam" to expand the medical program. The piercing technique of moving field irradiation with protons at an energy of 1 Gy and the utilization of the convergent beam ensure the ratio of the focal dose to the surface dose 200:1.