[A rare case of diencephalic cachexia in an adult female with cranio-pharyngioma]

Diencephalic cachexia (DС) is progressive weight loss despite a normal caloric intake and a satisfactory state of health, which is caused by hypothalamic lesions. This is a rare (about 100 cases were reported) and potentially fatal disorder of unknown pathogenesis. At present, there is no effective pharmacological therapy for the disorder. Cachexia may regress only if the tumor reduces in size, therefore the timely diagnosis and treatment are of vital importance for the patient. DС is typical of early childhood, and only a few cases have been reported in adults. We present a rare case of DС in a 24-year-old female with papillary craniopharyngioma.

[Craniofacial tumors blood supply]

Because of the spread to different anatomical regions, craniofacial tumors (CFTs) usually receive blood supply from several arterial systems, and CFT removal is often accompanied by abundant blood loss.

PURPOSE

The study purpose was to develop an algorithm of diagnostic angiography for planning surgical treatment of CFT patients.

MATERIAL AND METHODS

Complex preoperative angiography was performed in 72 patients with craniofacial tumors, aged 10 to 78 years (mean age, 45.5 years), who underwent surgical treatment at the Burdenko Neurosurgical Institute in the period from 2012 to 2015. At the first stage, blood supply to tumors was quantified using SCT perfusion. Then, depending on an assessed degree of tumor vascularization, direct angiography or modern minimally invasive angiographic techniques (3D TOF HR MR angiography, SCT angiography) were applied.

RESULTS

In 12 cases of hypervascular tumors, accessible afferents were preoperatively embolized through the external carotid artery, which was accompanied by an increase in the blood supply to tumors via alternative routes of the external and internal carotid arteries. The obtained data were used to plan the surgical approach. A comparative analysis of the SCT perfusion data and the expression level of endothelial markers in histological specimens revealed no significant correlation.

CONCLUSION

The study demonstrated the importance of a comprehensive assessment of the blood supply to CFTs in planning of the surgical treatment and enabled the development of algorithms for preoperative angiographic diagnosis, depending on the baseline clinical and radiological data.

Diffusion Kurtosis Imaging in the Assessment of Peritumoral Brain Edema in Glioblastomas and Brain Metastases

Aim: to explore the opportunities of application of diffusionkurtosis imaging (DKI) for assessment and estimation of diffusion scalar metrics in different locations of peritumoral edema for extra- and intracerebral tumors and in contralateral normal tissue.

Materials and methods. 38 patients with supratentorial brain tumors were investigated: 24 (63%) patients with primarily revealed glioblastomas (GB) and 14 (37%) patients with solitary cancer brain metastasis (MTS). MRI was performed on 3.0 T MR-scanner (Signa HDxt, General Electric, USA) with the standard protocols for brain tumor and additional protocol for DKI. The standard protocol for brain tumor included: T1-, T2-weighted images, T2-FLAIR, DWI,  T1 with contrast enhancement. Diffusion kurtosis MRI based on SE  EPI with TR = 10000 ms, TE = 102 ms, FOV = 240 mm, isotropic voxel size 3 × 3 × 3 mm3, 60 noncoplanar diffusion directions. We  used three b-values: 0, 1000 and 2500 s/mm2. Аcquisition time was 22 min. Total acquisition time was near 40 min. This study was approved by Ethical committee of Burdenko National Scientific  and Practical Center for Neurosurgery. Parametric maps were  constructed for the following diffusion coefficients: mean (MK),  transverse / radial (RK), longitudinal / axial (AK) kurtozis; medium  (MD), transverse / radial (RD) and longitudinal / axial (AD) diffusion; fractional anisotropy (FA) and a bi-exponential diffusion model  coefficients: axonal water fractions (AWF), axial (AxEAD) and radial  (RadEAD) extra-axonal water diffusion and the water molecules  trajectory tortuosity index (TORT). Normative quantitative indicators  were obtained for the six regions of the peritumoral zone as they  moved away from the tumor (region 2) to the edema periphery  (regions 4–5), as well as in the normal brain on the contralateral  hemisphere (C/L) (zone 7). A comparative analysis of these  indicators was conducted for cases with GB and MTS. DKI scalar metrics were estimated using Explore DTI (http://www.exploredti.com/).

Results. Anatomic MRI (T1 without/with contrast enhancement) for  all cases with GB and MTS visualized a contrast enhancement tumor.  The peritumoral edema, spreading mainly over the brain white  matter, was well visualized on T2-FLAIR. Diffusion kurtosis  coefficients decreased in the near peritumoral edema (regions 2–3)  and a gradually increased to the edema periphery (regions 5–6). In Region 2, MK in both GB and MTS groups were MKGB(2) = 0.637 ±  0.140 and MKMTS(2) = 0.550 ± 0.046; RK in this region were  RKGB(2) = 0.690 ± 0.154 and RKMTS (2) = 0.584 ± 0.051.  Differences both MK and RK coefficients in patients with GB and MTS of region 2 were significant (p < 0.001). There were no differences in AK values for GB and MTS in region 2 (p > 0.05), but in regions 3  and 4 differences were observed (p < 0.01). The minimum value of  AK in the central edema (regions 3–4) was AKMTS(3–4) = 0.433 ± 0.063 in patients with MTS. The values of MK and RK on the  contralateral side in patients with MTS were significantly higher than  in the GB group (p < 0.02); MKC/LMTC = 0.954 ± 0.140, RKC/LMTC  = 1.257 ± 0.308 and MKC/LGB = 0.829 ± 0.146, RKc/LGB = 0.989  ± 0.282. There was no significant difference for contralateral AK between the groups.

Conclusions. We found that DKI scalar metrics are the sensitive  tumor biomarkers. It allows us to perform a robust differentiation  between the infiltrating GB tumor and purely vasogenic edema of  МТS. The obtained results will allow further differential diagnosis of  extra- and intracerebral tumors and can be used to plan surgical /  radiosurgical treatment for brain tumors.

[Gene mutations in patients with hereditary cavernous malformations]

AIM

To identify mutations in cerebral cavernous malformation (CCM) genes in patients with hereditary and sporadic CCMs in the Russian population.

MATERIAL AND METHODS

Blood samples from 73 randomly selected patients, including 29 MRI-confirmed familial cases, 8 clinically confirmed familial cases and 38 so-called sporadic cases, were examined. A search for large deletions/duplications was performed using multiplex ligation-dependent probe amplification (MPLA). For MLPA-negative samples, the whole genome sequencing was performed to search for single nucleotide polymorphisms (SNP).

RESULTS

Deletions in three genes (ССМ1, ССМ2, ССМ3) were identified in 14 patients, including 5 without definitely established familial type, in whom the familial character of disease was not confirmed by clinical and neuroimaging results. SNP mutations were found in 13 patients, CCM gene mutations in 27. Mutations were detected in 91.7% of familial cases. In two patients, new CCM3 deletions were identified. Gene distribution was as follows: 60.7 for CCM1, 32.2 for CCM2 and 7.1% for CCM3. In two members of a family with hereditary CCMs, no high effect mutations in the known CCM genes were found. Patients with mutations had greater severity of disease. Two patients with CCM3 mutations demonstrated the most aggressive clinical course. De novo formation and growth of CCM were observed only in patients with mutations.

CONCLUSION

The distribution of pathogenic mutations in known CCM genes is consistent with other large-scale studies. Familial CCMs are associated with more severe disease course and may be caused by mutations beyond the known CCM genes.

[Long association tracts of the human white matter: an analysis of 18 hemisphere dissections and in vivo HARDI-CSD tractography]

BACKGROUND

Anatomy of the conduction tracts of the cerebral cortex has been studied for a long time. Invention of diffusion tensor tractography renewed interest in this subject. The objectives of this work were to develop and improve protocols for dissection of the long association tracts of the human brain with studying the features of their segmentation, topography, and variability, compare the obtained data with the MR tractography data, and prepare for further clinical and anatomical studies.

MATERIAL AND METHODS

We used 18 cerebral hemispheres (from 10 males and 8 females; 9 left and 9 right hemispheres). The mean age of cadavers was 68 years. Specimen were fixated in accordance with the Klingler technique. Immediately after collection, specimens were placed in a 10% formalin solution for at least 4 weeks. After that, the pia was removed; specimens were frozen at -20 °C for a week and then unfrozen in a 96% ethanol solution for a day. We performed 10 lateral dissections, 2 lateral dissections with isolation of the frontal aslant tract, 2 basal dissections, 1 combined basolateral dissection, 2 frontal dissections, and 1 medial dissection. At the time of dissection and after it, specimens were stored in a 96% ethanol solution. Modified, disposable, therapeutic wooden spatulas were used for manipulations. A microscope (magnification of 6-40x) was used in 2 lateral and 2 basal dissections. MR tractography (HARDI-CSD) was carried out in 5 healthy volunteers using a GE Signa HDxt MRI scanner a field strength of 3.0 T.

RESULTS

We clearly identified the following fascicles: the arcuate fascicle (AF) and superior longitudinal fascicle (SLF) in 6/6 hemispheres on the right and in 5/6 hemispheres on the left, the inferior longitudinal fascicle (ILF) in 3/6 hemispheres on the left and in 4/6 hemispheres on the right, the uncinate fascicle (UF) in 4/4 hemispheres on the left and in 4/4 hemispheres on the right, and the inferior fronto-occipital fascicle (IFOF) in 4/4 hemispheres on the left and in 3/4 hemispheres on the right. Identification was less successful in the case of the frontal aslant tract (FAT) in 1/2 hemispheres on the left and in 0/2 hemispheres on the right. The used technique failed to identify the vertical occipital fascicle (VOF) of Wernicke, a segment of the superior longitudinal fascicle SLF I, and the middle longitudinal fascicle (MdLF). The MR tractography HARDI-CSD data were compared with the dissection data. We described in detail segmentation of the superior longitudinal, arcuate, and inferior fronto-occipital fascicles. Contradictory data were obtained for the superior longitudinal fascicle: a two-segment structure (SLFh and SLFv) was found in most (10/12) specimens, while a three-segment structure was revealed in the other (2/12) specimens (identified SLF II and SLF III). In the arcuate fascicle, the ventral and dorsal segments were successfully identified in 2/12 cases (1 left and 1 right), whereas identification failed in the other cases. During dissection of the inferior fronto-occipital fascicle, we could identify its surface layer in 1 of 8 cases (left) and its deep layer in one more case (left).

CONCLUSION

Examination of the long association tracts using the Klingler technique has significant limitations in the fiber intersection areas (sagittal striatum). The frontal aslant tract was least studied; we proposed a special anterior dissection technique for its isolation. The superior longitudinal fascicle can have both the two-segment (10/12) and three-segment (2/12) structure. Investigation of the segmental anatomy of the long association tracts will be continued in further dissections. When planning neurosurgical interventions in the projection areas of the long association tracts, both preoperative HARDI-tractography and anatomical dissections ex vivo, based on the proposed protocols, can be recommended for the operating surgeon to master a three-dimensional picture of the tract topography.

[Hemispherectomy in the treatment of pediatric symptomatic epilepsy of children]

INTRODUCTION AND PURPOSE

Hemispherectomy is a recognized option in the treatment of symptomatic forms of intractable focal epilepsy in patients with developmental brain malformations and some acquired lesions of one the hemispheres. The prognosis for an outcome of the technique is important in terms of the indications for surgical treatment.

MATERIAL AND METHODS

We described the hemispherectomy technique and its variants and analyzed our own experience of surgery in 40 children. The most common (27 cases) brain pathology was extended unilateral cortical dysplasia with polymicro- or pachygyria and consequences of perinatal stroke. Six children had Rasmussen encephalitis; 6 patients had hemimegalencephaly; 1 child with Sturge-Weber syndrome had angiomatosis of the soft meninges. The patients' mean age was 3 years. Functional hemispherectomy (hemispherotomy) was used in most cases (37); 3 patients underwent anatomical hemispherectomy.

RESULTS

At the time of discharge, seizures resolved in all patients; later, no seizure recurrence was observed in 25 out of 29 cases with known follow-up (the follow-up median was 2.5 years), which corresponded to class 1 outcomes on the ILAE scale (86%). Serious complications developed in 2 cases; 1 patient died; hydrocephalus and the need for bypass surgery occurred in other 2 children. These results are discussed along with the literature data, and the indications for hemispherectomy are provided.

CONCLUSION

Hemispherectomy is a reliable and effective technique for treatment of symptomatic hemispheric forms of epilepsy in children. More than in 80% of patients with congenital or acquired pathology of one of the cerebral hemispheres, its deafferentation or resection leads to persistent elimination of seizures. Children with severe forms of intractable epilepsy should be promptly referred to dedicated centers to address the issue of advisability of surgical treatment.

[Endoscopic transsphenoidal resection of pituitary adenomas invading the cavernous sinus]

INTRODUCTION

Pituitary adenomas are benign growths that invade the cavernous sinus (CS) in 10-15% of cases. There are different types of microsurgical and endoscopic approaches enabling resection of tumors from the CS cavity that is a relatively small and hard to reach anatomical structure comprising eloquent neurovascular structures.

MATERIAL AND METHODS

A study group included 97 patients with pituitary adenomas (PAs) invading the CS. PAs were resected using an endoscopic technique: adenomas were resected from the CS cavity through a standard endoscopic endonasal transsphenoidal approach in 62 cases; a lateral extended transsphenoidal endoscopic approach was used in 35 cases. A control group included patients with PAs spreading into the laterosellar region who were operated on using microsurgical extra-intradural (n=14) and transsphenoidal (n=149) approaches. In the study group, the degree of PA invasion into the CS cavity was determined using the Knosp scale.

RESULTS

In the study group, total tumor resection was achieved in 49 (50.5%) cases, subtotal resection in 39 (40.2%) cases, and partial resection in 9 (9.3%) patients. In the case of visual disorders (n=70), vision improvement was achieved in 41.4% of cases. Vision deterioration was detected in 11.4% of cases; no vision changes were in 47.1% of cases. Patients (27.8%) who had not had visual impairments before surgery had no negative changes in vision in the postoperative period. The development/augmentation of oculomotor disorders in the study group occurred in 14 (14.4%) cases. In the study group, hormonal remission of the disease in patients with hormone-active PAs was in 26.7% of cases (n=12). There were no cases of nasal liquorrhea, meningitis, and death in the study group.

CONCLUSION

Endoscopic endonasal transsphenoidal resection of PAs invading the CS is a more efficient and safer surgical technique compared to microsurgical techniques (transsphenoidal and extra-intradural approach). The lateral extended transsphenoidal endoscopic approach enables resection of PAs with massive invasion into the CS (Grade III and Grade IV, Knosp scale) and has less postoperative complications compared to the extra-intradural approach (p<0.05).

[Surgical anatomy of the peri-insular association tracts. Part I.The superior longitudinal fascicle system]

AIM

To study the peri-insular association tract anatomy and define the permissible anatomical boundaries for resection of glial insular tumors with allowance for the surgical anatomy of the peri-insular association tracts.

MATERIAL AND METHODS

In an anatomic study of the superior longitudinal fascicle system (SLF I, SLF II, SLF III, arcuate fascicle), we used 12 anatomical specimens (6 left and 6 right hemispheres) prepared according to the Klingler's fiber dissection technique. To confirm the dissection data, we used MR tractography (HARDI-CSD-tractography) of the conduction tracts, which was performed in two healthy volunteers.

RESULTS

Except the SLF I (identified in 7 hemispheres by fiber dissection), all fascicles of the SLF system were found in all investigated hemispheres by both fiber dissection and MR tractography. The transcortical approach to the insula through the frontal and (or) parietal operculum is associated with a significant risk of transverse transection of the SLF III fibers passing in the frontal and parietal opercula. The most optimal area for the transcortical approach to the insula is the anterior third of the superior temporal gyrus that lacks important association tracts and, consequently, a risk of their injury. The superior peri-insular sulcus is an intraoperative landmark for the transsylvian approach, which enables identification of the SLF II and arcuate fascicle in the surgical wound.

CONCLUSION

Detailed knowledge of the peri-insular association tract anatomy is the prerequisite for neurosurgery in the insular region. Our findings facilitate correct identification of both the site for cerebral operculum dissection upon the transcortical approach and the intraoperative landmarks for locating the association tracts in the surgical wound upon the transsylvian approach to the insula.

[A correlation between diffusion kurtosis imaging and the proliferative activity of brain glioma]

The aim of the study was to assess the capabilities of diffusion kurtosis imaging (DKI) in diagnosis of the glioma proliferative activity and to evaluate a relationship between the glioma proliferative activity index and diffusion parameters of the contralateral normal appearing white matter (CNAWM).

MATERIAL AND METHODS

The study included 47 patients with newly diagnosed brain gliomas (23 low grade, 13 grade III, and 11 grade IV gliomas). We determined a relationship between absolute and normalized parameters of the diffusion tensor (mean (MD), axial (AD), and radial (RD) diffusivities; fractional (FA) and relative (RA) anisotropies) and diffusion kurtosis (mean (MK), axial (AK), and radial (RK) kurtosis; kurtosis anisotropy (KA)) and the proliferative activity index in the most malignant glioma parts (p<0.05). We also established a relationship between the tensor and kurtosis parameters of CNAWM and the glioma proliferative activity index (p<0.05).

RESULTS

The correlation between all the absolute and normalized diffusion parameters and the glioma proliferative activity index, except absolute and normalized FA and RA values, was found to be statistically significant (p<0.05). Kurtosis (MK, AK, and RK) and anisotropy (KA, FA, RA) values increased, and diffusivity (MD, AD, RD) values decreased as the glioma proliferative activity index increased. A strong correlation between the proliferative activity index and absolute RK (r=0,71; p=0.000001) and normalized values of MK (r=0.8; p=0.000001), AK (r=0.71; p=0.000001), RK (r=0.81; p=0.000001), and RD (r=-0.71; p=0.000001) was found. A weak, but statistically significant correlation between the glioma proliferative activity index and diffusion values RK (r=-0.36; p=0.014), KA (r=-0.39; p=0.007), RD (r=0.35; p=0.017), FA (r=-0.42; p=0.003), and RA (r=-0.41; p=0.004) of CNAWM was found.

CONCLUSION

DKI has good capabilities to detect immunohistochemical changes in gliomas. DKI demonstrated a high sensitivity in detection of microstructural changes in the contralateral normal appearing white matter in patients with brain gliomas.

[The structure of activation of the language zone in patients with intracerebral tumors according to fMRI with respect to tumor location and the functional asymmetry profile]

MATERIAL AND METHODS

A total of 50 patients were examined prior to surgical resection of intracranial tumors of the temporal and frontal lobes. Left-sided tumors were observed in 33 patients and right-sided tumors were observed in 17 patients. The functional asymmetry profile was determined using self-assessment, the Annet questionnaire, and the dichotic listening task. Twelve patients were left-handers or retrained left-handers and the remaining 38 patients were right-handers. FMRI examination was carried out on a 3.0 T SignaHDxt magnetic resonance tomograph (GE). The standard language block design paradigm was used in the study. We used the following tests: 1) recitation of months in reverse order; 2) generation of nouns according to the initial letters shown on the screen (K, M, L, N, P, C); 3) generation of verbs according to simple actions shown on the screen; 4) producing sentences using nouns shown on the screen; 5) listening to text through headphones. Data were processed using the standard BrainWave PA software (General Electric). Z-test was used in the range from 6 to 9. In all the studies, p<0.001. Statistical data processing included the nonparametric Spearman's test to determine the correlation between lateralization of the detected activation zone under speech load and tumor location (tumor is adjacent to the language zone, invades the language zone, or is located far from the language zone), as well as left- or right-handedness.

RESULTS

Among 16 patients (right-handers and 2 left-handers) the activation of language zones was observed only on the left side; in one left-handed patient, Broca's area was detected only on the right side. In other patients (including right-handers with right-sided tumors), lateralization of language zones was different, including bilateral. Statistical processing revealed that bilateral activation of both Broca's and Wernicke's areas was more frequently observed in left-handers. Broca's area was more frequently detected on the left side in the presence of a distant tumor, while this trend did not apply for Wernicke's area.

CONCLUSION

Localization of activation of Broca's area is more dependent on tumor location, while it depends on personal characteristics of an individual in the case of Wernicke's area.

[Supracerebellar transtentorial approach to tumors of the posterior portions of the medial temporal region]

OBJECTIVE

Despite the advances in microsurgery, the choice of the most adequate approach to the posterior part of the medial temporal region (MTR) remains a very controversial issue. The supracerebellar transtentorial approach (STA) is considered as the most preferable one, since it provides the optimal balance between retraction, incision, and resection of the brain tissue. Here, we present our consecutive series of 20 patients who underwent STA surgery.

MATERIAL AND METHODS

Twenty patients with glial tumors affecting the posterior MTR underwent STA surgery between 2006 and 2014. The mean age of the patients was 20 years. Benign tumors were predominant (18 out of 20 cases).

RESULTS

Resection of the posterior and middle MTRs was conducted in 16 cases. The anterior MTR was accessed through STA in 1 patient only; in 2 patients, STA was combined with the infraoccipital approach. Cerebellar edema occurred in 4 patients, with hemiparesis persisting in one of the cases for 1 year after surgery. Of 8 patients with drug resistant epilepsy, the Engel class 1 or 2 outcome was achieved in 6 cases within 1 year after surgery.

CONCLUSION

STA provides an excellent surgical route to the posterior and middle MTR portions; however, the anterior MTR portions cannot be reached safely. The operative risks of STA increase as the surgeon proceeds with resection of the anterior MTR portions. Anterior MTR structures can be removed using a combination of the supracerebellar and infraoccipital transtentorial approaches or two-stage resection.

Diffusion tensor imaging tractography and intraoperative neurophysiological monitoring in surgery of intracranial tumors located near the pyramidal tract

BACKGROUND

Practical application of methods for intravital examination of the brain pathways, such as preoperative diffusion tensor imaging (DTI) tractography and intraoperative neurophysiological monitoring, facilitates safer resection of intracranial tumors located near the pyramidal tracts (PTs).

PURPOSE

The study purpose was to investigate the relationships between intracerebral tumors of different histological nature and the pyramidal tract based on preoperative DTI tractography and various methods of intraoperative neurophysiological monitoring for intraoperative identification of the pyramidal tract, depending on different variants of the topographo-anatomic relationships between the pyramidal fascicle and the tumor.

MATERIAL AND METHODS

The study included 29 patients with supratentorial tumors of a different histological structure. Of these, 2 patients had grade I tumors, 8 patients had grade II tumors, 4 patients had grade III tumors, 11 patients grade IV tumors, and 4 patients had brain metastases. The patients underwent preoperative DTI tractography with PT reconstruction and evaluation of the topographo-anatomic relationships between the pyramidal tract and the tumor (tract: intact, infiltrated, displaced). Neurophysiological monitoring (direct electrical stimulation in 24 patients and transcranial motor evoked potentials in 26 patients) was used during surgery. The strength of stimulating current for direct stimulation was varied from 10 to 30 mA. Postoperatively, the motor function was evaluated by using a 5-score scale, and the data were compared to the preoperative data.

RESULTS

According to preoperative DTI tractography in patients with grade I-II gliomas, the corticospinal tracts were infiltrated in 2 cases, displaced in 3 cases, and intact in 5 cases. In patients with grade III-IV gliomas and metastases, the tracts were infiltrated in 8 cases, displaced in 4 cases, and intact in 7 cases. Motor responses evoked by direct electrical stimulation were obtained in 5 out of 6 patients with the pyramidal tract displaced by the tumor and in 7 out of 8 patients with the tract infiltrated by the tumor. In the case of the intact tract, the PT to tumor distance and the stimulus strength play an important role: responses were obtained in 4 out of 10 patients. In the case of transcranial motor evoked potentials (TCMEPs), no dynamics of the potential amplitude was detected in 17 out of 26 patients during surgery; a reduced TCMEP amplitude was detected in 9 patients.

CONCLUSION

1. Patients with an infiltrated or displaced pyramidal tract had significantly more often hemiparesis before surgery and aggravation of hemiparesis after the surgery compared to patients with an intact tract. 2. In the case of direct electrical stimulation of the PT, motor responses (according to preoperative DTI tractography) were significantly more often observed for the pyramidal tract infiltrated and displaced by the tumor. 3. A reduction in the motor neurologic deficit in the postoperative period was significantly more often observed for application of a larger current strength during direct electrical stimulation. 4. Persistence of the TCMEP amplitude during surgery is a reliable predictor for no aggravation of the motor neurological deficit after surgery. Postoperative aggravation of hemiparesis was significantly more often observed when TC MEPs decreased during surgery.

Criteria of the efficacy of surgical brain revascularization in patients with chronic cerebral ischemia

PURPOSE

The article analyzes results of surgical revascularization in patients with symptoms of chronic cerebral ischemia caused by occlusion of the carotid arteries.

MATERIAL AND METHODS

We analyzed 404 surgeries for placement of extra-intracranial microvascular anastomoses (EICMAs) performed in 376 patients between 2000 and 2015. All patients underwent detailed neurological and neuropsychological examinations before surgery and throughout the follow-up period using the neurological deficit scale (NIHSS). Additionally, the medical history data, technical features of surgery, and results of instrumental tests were recorded. For a more detailed study of the cerebral circulation, a SCT perfusion examination was conducted in 58 patients before and after placement of EICMA.

RESULTS

All patients were divided into 3 groups, depending on the surgical treatment outcomes: improvement (53%), without significant changes (43%), and worsening of clinical symptoms (4%). A statistical analysis revealed that the efficacy of EICMA surgery ranged from 22 to 79% and was reliably confirmed by hemodynamic and anamnestic factors as well as by technical details of surgery.

CONCLUSION

When determining the indications for surgical revascularization in patients with ischemic stroke consequences, the patient's age, occlusion duration, location and size of ischemic lesions should be considered. Also, the choice of the acceptor artery and blood flow through the created anastomosis are of great importance.

[Perfusion criteria of the EICMA efficacy in patients with symptomatic occlusion of the internal carotid artery]

AIM

To investigate changes in cerebral perfusion in patients with unilateral internal carotid artery occlusion before and after surgical revascularization of the brain, depending on the clinical efficacy of surgical treatment.

MATERIAL AND METHODS

The study included 60 patients with unilateral ICA occlusions who underwent placement of an extra-intracranial microvascular anastomosis (EICMA). All patients underwent a CT perfusion study before and after cerebral revascularization. In addition, the degree of neurological deficit was evaluated before surgery and during follow-up (3 and 8-10 months) using the NIHSS score.

RESULTS

All patients were divided into 3 groups, depending on the results of surgical treatment: objective improvement (43 patients), no changes (14 patients), and worsening of clinical symptoms (3 patients). In each group, the absolute and relative perfusion parameters (MTT, CBV, and CBF) were analyzed to identify the perfusion criteria for the EICMA efficacy. A significant relationship between the clinical efficacy of EICMA and a baseline perfusion deficit and its change after anastomosis placement was found.

CONCLUSION

Placement of EICMA is effective treatment for patients with symptomatic ICA occlusions and an increase in the blood transit time in the hemisphere ipsilateral to occlusion by more than 40% compared to that in the opposite side provided that perfusion is recovered in more than one area of the MCA territory (in accordance with the ASPECTS scale).

[Surgical treatment of cerebral vascular diseases]

Theoretical and practical aspects of the complex treatment of brain and spinal vascular diseases using microsurgical, endovascular and radiosurgical methods are considered. Authors present the data demonstrating that, due to the implementation of the program of development of vascular centers in the Russian Federation, considerable progress was made in the treatment of cerebral aneurisms and hemorrhagic stroke. In author's opinion, wide introduction of surgical methods in the treatment of occlusive lesions of the blood vessels supplying the brain is needed.

[SCT perfusion in the diagnosis of sellar and parasellar tumors]

The study is devoted to the use of a minimally invasive method of SCT perfusion for the differential diagnosis of sellar and pаrаsellar tumors. Given a wide differential diagnostic range of tumors occurring in this area, the tumor perfusion indicators were used as an auxiliary diagnostic criterion.

MATERIAL AND METHODS

The study analyzed outcomes in 115 patients with various tumors of the sellar area who underwent surgery or biopsy for histological verification of the diagnosis.

RESULTS

The statistically significant differences were obtained for certain groups of tumors based on the values of hemodynamic parameters (p<0.05) that enable, with a high confidence, making a conclusion on the histologic type of most tumors.

CONCLUSION

These findings demonstrated that SCT perfusion is a highly informative method of the preoperative differential diagnosis of these tumors. The sensitivity and specificity of SCT perfusion in the study were 100% and 81.2%, respectively.

3D-TOF MR-angiography with high spatial resolution for surgical planning in insular lobe gliomas

Despite the obvious progress in modern neurosurgery, surgery for glial tumors of the insular lobe is often associated with a high risk of postoperative neurological deficit, which is primarily caused by damage to perforating arteries of the M1 segment of the middle cerebral artery.

OBJECTIVE

The work is aimed at evaluating the effectiveness of high resolution time-of-flight (3D-TOF) MR angiography in imaging of medial and lateral lenticulostriate arteries and determining their relationship to tumor edge in patients with gliomas of the insula.

MATERIAL AND METHODS

3D-TOF MR angiography data were analyzed in 20 patients with primarily diagnosed cerebral gliomas involving the insula. All patients underwent non-contrast enhanced 3D-TOF MR angiography. In 6 cases, 3D-TOF MRA was performed before and after contrast enhancement.

RESULTS

3D-TOF angiography before intravenous contrast injection was capable of visualizing the medial lenticulostriate arteries in 19 patients (95% of all cases) and lateral lenticulostriate arteries in 18 patients (90% of all cases). Contrast-enhanced 3D-TOF angiography allows for better visualization of both the proximal and distal segments of lenticulostriate arteries. Three variants of relationship between the tumor and lenticulostriate arteries were identified. Variant I: the tumor grew over the arteries without their displacement in 2 cases (10% of the total number of observations); variant II: the tumor caused medial displacement of arteries without growing over them in 11 cases (55% of the total number of observations); variant III: the tumor partially grew over and displaced arteries in 2 cases (10%). In 25% of cases (5 patients), tumor was poorly visualized on 3D-TOF MR angiograms because their signal characteristics did not differ from those of the medulla (tumor tissue was T1 isointense). As a result, it was impossible to determine the relationship between the tumor and lenticulostriate arteries.

CONCLUSION

High spatial resolution time-of-flight MR angiography can be recommended for preoperative imaging of lenticulostriate arteries to plan the extent of neurosurgical resection in patients with glial tumors of the insular lobe.

Multiple primary liponeurocytoma of the central nervous system

We report a unique case of primary multiple liponeurocytoma. Liponeurocytoma is a rare benign tumor (Grade II) of the posterior cranial fossa with neural- or probably astrocytic-lineage cells; the tumor stroma contains mature adipocytes. This case is the thirty-eighth case of this pathology reported in the world literature and the first case of multiple form of this disease. We have provided a sufficiently thorough neuroradiological and histological picture that allows one to differentiate between a liponeurocytoma and other histological variants. Recommendations for the tactics for managing patients with this rare disease are proposed based on the analysis of treatment of this pathology reported in the world literature.

Rare cases of reflex epilepsy in patients with gliomas of the left hemisphere

We present the cases of symptomatic reflex epilepsy in patients with left hemisphere tumors. The first case: a 23-year-old man has had tonic-clonic seizures of the tongue with rare secondary localization over the past several months. The seizures were caused by intense tongue movements, in particular rightward and leftward (when having chewing gum or a candy in his mouth), but not during speech production or eating. MRI scanning detected a small tumor in the lower segments of the central gyrus. It was found during the surgery under electrophysiological control that the tumor (Gr II astrocytoma) resided in the zone corresponding to the right half of the tongue and included this zone. The tumor was partially resected. The second patient, a 52-year-old man, has been suffering from generalized seizures since 1998. The seizures were caused by intense verbal load, in the beginning of spontaneous speech and subsequently when the patient was listening to others' speech or was writing. Spontaneous seizures emerged when the patient stopped taking his anti-seizure medications unilaterally. MRI showed glioma in the posterior segments of the left temporal lobe. The patient underwent radiation and chemotherapy. In 2013, the patient's condition worsened (right-sided hemiparesis and severe speech impairment emerged); the tumor was partially resected and an extensive cyst was opened. The third patient, a 38-year-old man with Gr III astrocytoma in the left insula with past medical history of spontaneous vegetative seizures, had only a seizure anticipation caused by strong smells. All the patients were prescribed chemo-, radiation, and anti-seizure therapy.

Neuroanatomical basis for traumatic coma: clinical and magnetic resonance correlates

In this paper, the relationship between brain lesion localization (verified by magnetic resonance imaging (MRI)) and the severity of traumatic brain injury (TBI) and its outcomes is presented. Magnetic resonance studies in different modes (T1, T2, FLAIR, DWI, DTI, T2 * GRE, SWAN) were performed in 162 patients with acute TBI. Statistical analysis was done using Statistica 6, 8 software and R programming language. A new advanced MRI-based classification of TBI was introduced implying the assessment of hemispheric and brainstem traumatic lesions level and localization. Statistically significant correlations were found between the Glasgow coma and outcome scales scores (p < 0.001), and the proposed MRI grading scale scores, which means a high prognostic value of the new classification. The knowledge of injured brain microanatomy coming from sensitive neuroimaging, in conjunction with the assessment of mechanisms, aggravating factors and clinical manifestation of brain trauma is the basis for the actual predictive model of TBI. The proposed advanced MRI classification contributes to this concept development.

The long-associative pathway of the white matter: modern view from the perspective of neuroscience

This review presents basic information about white matter tracts of the human brain, with a special emphasis being placed on long associative fibers (superior and inferior longitudinal fascicles, inferior frontooccipital fascicles, fasciculus arcuatus and fasciclus uncinatus): their structure, history, functions, methods of preoperative and intraoperative identification during neurosurgical operations. Neurological symptoms caused by a damage to each of the above-described long associative fiber are described. There is a detailed analysis of methods of neuropsychological testing and neurophysiological identification in white matter fiber tract mapping in focal brain lesions.

Local epileptic activity, histological and neuroimaging findings in symptomatic epilepsy

OBJECTIVE

This study is aimed at revealing the relationship between local interictal epileptic activity, cytoarchitectural disturbances and magnetic resonance imaging (MRI) findings.

MATERIAL AND METHODS

We prospectively investigated a series of 25 patients with symptomatic epilepsy due to isolated forms of focal cortical dysplasia (FCD) or hippocampal sclerosis and low-grade tumours associated with FCD, all of whom underwent tailored surgical procedures under intraoperative electrocorticography; we conducted neuropathological examinations of 92 biopsies taken from different places. We examined the relationship between dysplastic changes in the cortex and the absence or presence of seizure patterns (SPs), including regular spikes/sharp waves, recruiting discharges, paroxysmal fast activity and rhythmic delta-theta activity. Comparisons with MRI findings were also performed.

RESULTS

Complete removal of the SPs zone was associated with better results of surgical treatment. Areas with isolated architectural abnormalities were associated with SPs significantly more often than those where the cortex contains immature or giant neurons; these areas were associated with SPs more than areas containing dysmorphic neurons. The extent of MRI signs appearance in the neocortex correlated neither with the presence of SPs nor with the types of histological changes.

CONCLUSIONS

We suppose an inverse relationship between the morphological changes in neurons and their ability to generate epileptic activity. Electrocorticography may be used for the identification of the MRI-negative epileptogenic lesions.

[Structural and functional peculiarity of brain activity to performance and imaginary motor tasks in healthy persons (EEG and fMRI study)]

Bioelectrical (EEG) and hemodynamic (fMRI-response) cerebral reactions to performance and imaginary motor tasks by right or left hand were analyzed in 15 right-handed healthy persons (21-39 years old). During actual movement the main fMRI-response was registered in the area of central gyrus of the hemisphere contralateral to the working hand. Areas of activation were also revealed in the supplemental motor area and the ipsilateral hemisphere of the cerebellum. EEG data showed coherence increase in high frequency alpha- and beta-bands in the activated hemisphere. In imaginary motor tasks the intensity and topography of fMRI-response became the more variable; response was decreased in the motor area and in cerebellum, they increased in the subcortical structures and in the parietal association zones. EEG changes were very variable in this situation also; it was observe an increase of EEG coherence in the right hemisphere for higher frequency of alpha and beta spectral bands. Changes of power spectrum parameters were similar to performance and imaginary motor tasks. Spectrum power and middle frequency of beta band were increased. Topographically these changes did not correspond to activated hemisphere and it was more in the left hemisphere. These changes were reflected nonspecific component of reaction.

fMRI study of the dominant hemisphere for language in patients with brain tumor

THE AIM OF THE STUDY

Paper describes a study of language lateralization of patients with brain tumors, measured by preoperative functional magnetic resonance imaging (fMRI) and comparison results with tumor histology and profile of functional asymmetry.

METHODS

During the study 21 patient underwent fMRI scan. 15 patients had a tumor in the left and 6 in the right hemisphere. Tumors were localized mainly in the frontal, temporal and fronto-temporal regions. Histological diagnosis in 8 cases was malignant Grade IV, in 13 cases--Grade I-III. fMRI study was perfomed on scanner "Signa Exite" with a field strength of 1.5 As speech test reciting the months of the year in reverse order was used. fMRI scan results were compared with the profile of functional asymmetry, which was received with the results of questionnaire Annette and dichotic listening test.

RESULTS

Broca's area was found in 7 cases in the left hemisphere, 6 had a tumor Grade I-III. And one patient with glioblastoma had a tumor of the right hemisphere. Broca's area in the right hemisphere was found in 3 patients (2 patients with left sided tumor, and one with right-sided tumor). One patient with left-sided tumor had mild motor aphasia. Bilateral activation in both hemispheres of the brain was observed in 6 patients. All of them had tumor Grade II-III of the left hemisphere. Signs of left-handedness were revealed only in half of these patients. Broca's area was not found in 4 cases. All of them had large malignant tumors Grade IV. One patient couldn't handle program of the research.

CONCLUSIONS

Results of fMRI scans, questionnaire Annette and dichotic listening test frequently were not the same, which is significant. Bilateral activation in speech-loads may be a reflection of brain plasticity in cases of long-growing tumors. Thus it's important to consider the full range of clinical data in studying the problem of the dominant hemisphere for language.