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I N Pronin

Publications and source records attributed to I N Pronin.

At least 37 records · Page 2Linked to original sources
PubMedDate not supplied

[Analysis of the results of surgical treatment for symptomatic epilepsy caused by temporal lobar neoplasms].

The present study involves the analysis of the results of surgical treatment in 35 patients with drug-resistant epilepsy caused by local temporal lobar lesions: glioma without growth (n = 31), gliosis (n = 1), and cavernoma (n = 3). The medial location of neoplasms involving the hippocampus was noted in 25 cases, their extrahippocampal location was observed in 10 cases. The history of seizures was 2 to 18 years; the duration of a postoperative follow-up was 1 to 6 years. Electrocorticographic and EEG findings indicated that in all cases the eliptogenic zone was located in the medial portions of the temporal lobes at the site of lesion. The first stage of surgery was to remove a neoplasm; the adjacent portions of an epileptogenic zone were resected only with preserved convulsive activity in the surrounding areas. Good results (Classes I-II) were observed in cases of the medial location of a lesion in both total removal of a neoplasm and additional resections; in the group of patients the results were better than in routine removal (seizures ceasing in 4 of 5 and in 3 of 12 patients, respectively). Bad results (Classes III-V) were noted with partial removal of a neoplasm from the medial portions (n = 4), there were much better results (Classes I-II) with its total removal from the medial portions and with its partial removal from other areas. With total removal of extrahippocampal neoplasms, seizures were retained (Classes III-IV); additional resections of neocortical zones (n = 2) failed to improve the results of treatment. With resections in the entorial cortical area, the results were better (Class II). Our findings confirm that hippocampal removal plays an important role in symptomatic temporal epilepsy for an adequate monitoring of seizures.

Adolescent↗
PubMedDate not supplied

[Chiasmatic cavernoma].

Hemorrhage into the structures of the anterior visual pathway, apoplexy of the chiasma or optic nerves, is a rare pathology that can be caused by different pathological processes among which cavernous angioma and arteriovenous malformation are more frequently mentioned. The cause of chiasmatic apoplexy may be also hemorrhage into the tumor--chiasmatic glioma of blood penetration into the chiasma in pituitary apoplexy. The authors describe a rare case of chiasmatic apoplexy whose cause was chiasmatic cavernoma. In addition to acute visual disorders suggesting the involvement of the left optic nerve, chiasma, and left visual pathway, 23-year-old patient had endocrine disorders as polyuria, polydipsia, which first suggests craniopharyngioma and glioma of the chiasma. A capsule and hematomic clots were removed from the thickened left optic nerve and left chiasmatic half during surgery. Only did a morphological study involving immunohistochemical analysis permit identification of the process as hemorrhage from cavernous micromalformation with the formation of hematoma.

Adult↗
PubMedDate not supplied

[Analysis of factors influencing the prediction of surgical treatment for symptomatic temporal lobe epilepsy].

The results of treatment were analyzed in 37 patients with drug-resistant symptomatic temporal lobe epilepsy among whom there were 22 patients with low-grade intracellular tumors, 2 with cavernomas; 6 with cortical malformations, and 9 with residual organic lesions. Double pathology was noted in 4 patients. Mono- and multiregional lesions were observed in 30 cases. Removal of the site of lesion, extended medial resections, and temporal lobectomy were performed in 7, 5, and 25 cases, respectively. There was an association of the quality of outcomes with the scope of an intervention: the best results were achieved when the affected area with adjacent cortical portions was completely removed within the eliptogenic area. Resections for multiregional lesions are low effective.

Adolescent↗
PubMedDate not supplied

[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.

Adolescent↗
PubMedDate not supplied

[Specific features of manifestation of anterior optic tract gliomas in patients with type 1 neurofibromatosis: ophthalmological and neurovisualizational aspects].

Gliomas of the anterior optic tract (AOT) (optic nerves, chiasms, and visual tracts) are benign slowly growing tumors usually detectable in childhood. These are a rather heterogenic group of tumors. The pattern and course of the disease are frequently affected by the presence of type 1 neurofibromatosis (NF-1) in the patient. The ophthalmological symptoms of AOT lesion in the presence of NF-1 were analyzed in 80 patients aged 1 to 24 years (median 5 years). According to the ophthalmological symptoms and the pattern and extent of lesions to AOT structures, the authors identified 4 groups by the data of neurovisualization techniques (magnetic resonance imaging, computed tomography) and revealed that the ophthalmological pattern reflected the site and degree of lesion to AOT structures. At the same time it is shown that there is a group of silent tumors attending without visual disorders. These tumors have the similar neurovisualization pattern, such as a moderate thickening of AOT structures and they occur in 13.8% of cases, as shown by the authors.

Adolescent↗
PubMedDate not supplied

[A follow-up of patients with anterior optic tract glioma concurrent with type 1 neurofibromatosis].

Fifty-nine patients with anterior optic tract (AOT) lesion concurrent with type neurofibromatosis (NF-1) were followed up for 1 to 36 years (median 5 years). Based on the study, the authors identified several grades of the disease: - stabilization without intervention; - stabilization after treatment; - insignificant negative changes as a slight tumor growth and a further stabilization of the process; - occasionally negative changes irrespective of treatment. The behavior of a tumor is unpredictable. The onset of progression in infancy is a poor predictor. Ophthalmological symptoms are not the criterion that can be used to make a prognosis. The prognosis is largely determined by neurovisualization techniques and primarily magnetic resonance imaging. A uniform slight thickening of AOT structures irrespective of the extent of the process along the AOT should be referred to as a good prognosis. There was no spontaneous tumor regression in any case. By taking into account the beneficial effect of radiotherapy, the authors consider it expedient to use it as monotherapy and in combination with surgery. Bypass surgery on the spinal fluid system frequently fails to entirely solve the problem intracranial hypertension.

Blindness↗
PubMedDate not supplied

[Magnetic resonance tomography in the diagnosis of spinal cord tumors].

The authors generalize experience in the examination of 245 patients with suspected disease of the spinal cord by means of the Acutscan magnetic resonance tomograph (Instrumentarium firm, Finland) with ultralow intensity of the magnetic field. The application of the new method in neuroradiologic diagnosis--magnetic resonance tomography (MRT) possessing certain advantages over computed tomography and myelography enables the authors to make the correct topical diagnosis in most cases and visualize the inner structure of the tumor and its relation with the structures of the spinal canal. Tumors of the spinal cord were detected in 102 patients: intramedullary in 24, extramedullary-intradural in 31, extradural in 13, and craniospinal in 34 patients. It was established from analysis of the results that MRT possesses high informativeness in cases of intradural tumors of the spinal cord.

Diagnosis, Differential↗
PubMedDate not supplied

[The use of hyperventilation for improving the visualization of glial tumors of the brain in magnetic resonance tomography using the contrast substance Gd-DTPA].

This study was undertaken to evaluate the influence of hyperventilation (HV) as a test on the image contrast of brain glial tumors in enhanced magnetic resonance (MR) imaging. HV was performed for 2 min (30 breaths/min) before intravenous injection of Gd-DTPA (Magnevist), Schering AG, Germany, in a dose of 0.1 mmol/kg. A total of 19 patients with glial tumors of the brain were examined. After the functional test, the image contrast of tumor tissue was compared with tumor contrast after the standard enhanced MR imaging. Nineteen patients with brain tumors were assessed. The tumor types were histologically verified in all cases (nine malignancy degree I-II astrocytomas, six malignancy degree III astrocytomas, three ependymomas, one malignant oligodendroglioma). MRI was performed on a Magnetom 42 SP-1.0 T. There was an increase in the image contrast of degree I-II astrocytomas neither after the standard enhanced MRI nor after it in the presence of HV. On the contrary, in 2 cases there was an opposite effect--the tumor contrast decrease after the functional test. Ependymomas showed patterns of increases in contrast intensity from 10 to 13% as compared with the enhanced standard MRI in all cases. In these conditions the intrinsic structure and boundaries of tumors became more distinguished. Cases with malignant astrocytomas and oligodendroglioma had contrast enhancement increases as well. It is concluded that in cases with degree I-II astrocytomas, the use of HV does not improve the visualization of lesions. In ependymomas and anaplastic astrocytomas, HV aids in more significantly assessing the intrinsic structure and the extent of tumorigenesis and it may be useful as a functional test to assess the anaplastic extent of glial tumors of the brain and as a procedure enabling the contrast agent to be used in smaller dosages.

Astrocytoma↗
PubMedDate not supplied

[Acoustic neurinomas. Magnetic resonance tomography using the contrast medium Gd-DTPA].

The contrast agent Gd-DTPA was used in the diagnosis of neurinomas of the VIII nerve. The analysis of the findings led to the conclusion that the use of the agent improved the visualization of auditory neurinomas and contributed to their differentiation from the brain stem and cerebellum and that its was more advisable to apply contrast enhancement in tumors located in the internal acoustic meatus (microneurinomas) or large (including bilateral) tumors with stem compression.

Contrast Media↗
PubMedDate not supplied

[Magnetic resonance tomography in the diagnosis of intramedullary tumors].

The data of magnetic resonance imaging in 23 patients is hardly sufficient to characterize the histologic types of intramedullary tumors. However, the presence of cystous type of structure of intramedullary tumors on magnetic tomograms with nonhomogeneous (iso- or hypointensive) signal on T1-suspended tomograms or of hyper- or hypointensive signal on T2-suspended ones is to a great measure indicative of infiltration and diffuse growth of a tumor. A solid structure of intramedullary tumor with homogenous hyperintensive signals on both T1- and T2-dependent tomograms is more frequently indicative of a slowly growing tumor not involving the medulla, e.g. ependioma.

Adolescent↗
PubMedDate not supplied

[Gd-DTPA in the diagnosis of brain metastasis].

The potentialities of present-day methods of imaging (computer-aided and magnetic resonance tomography) in the diagnosis of metastatic involvement of the brain are discussed. Besides routine scanning, the authors assess the efficacy of a contrast agent Gd-DTPA (Magnevist, Schering AG, Germany) used in magnetic imaging. The potentialities of reinforced-aided tomography, 0.04 and 1.0 Tesla magnetic imaging are compared on the basis of 23 cases. The results indicate that magnetic imaging at low-intensity magnetic field is approximately as effective as computer-aided tomography in the assessment of metastatic involvement of the brain; contrast reinforcement with Gd-DTPA appreciably improves the informative value of the method in comparison with reinforced computer-aided tomography. As for 1.0 Tesla magnetic imaging, it is highly informative and accurate in assessment of the type (single or multiple) of the pathologic process. Extra contrast staining with Gd-DTPA makes magnetic imaging still more reliable and superior to computer-aided tomography and 0.04 T magnetic imaging in the diagnosis of metastatic involvement of the brain. In this investigation authors performed analysis of 23 observations with metastases (22 cases were hystological verified) and estimated possibilities of modern diagnostic methods such as CT (+CM), standard MR imaging and MRI with Gd-DTPA (Magnevist, Schering AG, Germany). Authors have noticed that MR imaging with contrast enhancement is more efficient in diagnosis of brain metastases in comparison with CT. Metastases showed the signal intensity increase after Gd-DTPA injection. Small tumors and nodi situated nearly skull base and in cerebellum were more distinguished on MR imaging with contrast enhancement than before it.

Adult↗
PubMedDate not supplied

[The contrast enhancement of brain and spinal cord tumors using Gd-DTPA in magnetic resonance tomography with an extra-low magnetic-field intensity].

The contrasting agent Gd-DTPA (Magnevist, Schering AG, Germany) was tested when used in magnetic resonance tomography using extra-low (0.04 T) magnetic field intensity in 68 patients with various brain and spine tumors. The agent was injected intravenously in a dose of 0.1 mmol/kg. No complications were found. The tests showed its high efficiency in the diagnosis of brain neoplasms (particularly in malignant intracerebral disorders, meningiomas and neurinomas). Benign astrocytomas induced no noticeable signal intensification on post-contrasting T1-weighed tomograms. In all cases of spinal tumors, the application of Gd-DTPA could specify the extent of tumor invasions, the presence of cysts and identify accessory tumor nodes in one case.

Adult↗
PubMedDate not supplied

[Use of Omniscan (gadodiamide) in magnetic resonance studies of the central nervous system (results of a multicenter study)].

The aim the study: was to conduct first in Russia multicenter trial of gadodiamide in brain and spine MRI in adult patients. Open noncomparative multicenter (5 clinical centres) study. Brain and spine MRI was performed in 190 adult patients with signs of CNS disorders. Field strength of MR imagers was 0.04-1.5 T. Gadodiamide ("Omniscan", "Nycomed Imaging", Nycomed) was injected IV in dose 0.1 mmol/ml. Contrast enhancement was obtained in 74% cases. Gadodiamide allowed to detect more new lesions, better differentiate borders and internal structure of lesions, to differentiate them from oedema and surrounding structures. Contrast-enhanced MR images were superior to non-enhanced T1 and T2-weighted images and to CT images (before and after contrast enhancement). Use of gadodiamide increased confidence in diagnoses in 90.4% cases, changed the diagnosis in 30.3% cases. The general number of adverse events was 2.6%. Adverse reactions to gadodiamide were seen in 1.6%; all of them were of mild intensity without need for therapy. Gadodiamide is an effective and safe nonionic paramagnetic contrast media for brain and spine MRI in adult patients.

Adolescent↗