Purpose: The first aim of this study was to compare the intratumoral and peritumoral blood flow parameters in glioblastomas and brain metastases measured by pseudocontinuous arterial spin labeling MRI (3D pCASL). The second aim of this study was to determine whether pCASL could aid in identifying the source of brain metastases.Materials and Methods: This study included 173 patients aged 12 to 83 years (median age—61 years), who were observed at the National Medical Research Center for Neurosurgery. All patients underwent preoperative MRI with pCASL perfusion. Thereafter patients were operated on and received histological diagnosis. No patients received preoperative chemo or radiotherapy.Results: The values of maximum and normalized intratumoral blood flow were significantly higher in the group with gliblastoma than in the group with brain metastases: 168.98 + −91.96 versus 152.1 + −173.32 and 7.6 + −8.4 versus 9.3 + −5.33 respectively (p <0.01). However, ROC analysis showed low AUC specificity and sensitivity (0.64, 70%, 60% for mTBF and 0.66, 77%, 62% for nTBF). Peritumoral blood flow parameters were also higher in the glioblastoma group (29.61 + −22.89 versus 16.58 + −6.46 for mTBF and 1.63 + −1.14 versus 0.88 + −0.38 for nTBF, respectively; p <0.01). ROC analysis showed the following measurements of AUC, specificity, and sensitivity (0.75, 68%, 73% for mTBF and 0.77, 58%, 91% for nTBF). Regarding pCASL and various histological subsets of brain metastases, the study found statistically significant differences between the lung and melanoma metastases and the lung and kidney metastases. ROC analysis gave the following values for lung and melanoma metastases: AUC—0.76, specificity—75%, and sensitivity—73% for mTBF; 0.83, 67%, and 93% respectively, for nTBF. For lung and kidney metastases: AUC—0.74, specificity—70%, and sensitivity—93% for mTBF; 0.75, 70%, and 93% respectively, for nTBF.Conclusions: pCASL could aid in differential diagnosis between glioblastoma and brain metastases. Measurement of peritumoral blood flow demonstrates higher specificity and sensitivity than with intratumoral blood flow. Moreover, pCASL provides the ability to distinguish lung metastases from kidney and melanoma metastases.

Возможности магнитно-резонансной томографии в оценке гидроцефалии

Aim . To study the role of CT perfusion in the differential diagnosis of histological subtypes of supratentorial malignant gliomas and to determine the degree of their malignancy. Materials and methods . The study included 34 patients (20 men and 14 women, with an average age of 52 years) with newly detected supratenorial glial tumors, who subsequently underwent neurosurgical treatment in the NMIC of neurosurgery with histological verification of the diagnosis. Depending on the histological diagnosis, three groups of patients were identified: 1) anaplastic astrocytomas, 2) glioblastomas, 3) anaplastic oligodendrogliomas. The CT-perfusion protocol was performed on a 64-slice Optima 660 (GE) scanner and consisted of three separate parts: a low-dose axial CT of the brain with a slice thickness of 5 mm (90 kV), a perfusion protocol performed according to a prolonged scheme, with two consecutive continuous series of scans, and a post-contrast series of CT images in a spiral scanning mode. In addition, all patients underwent an MRI examination (using a Signa Hdxt 3.0 T (GE) MR scanner, in T2, T2-FLAIR, SWAN, DWI, and T1 modes before and after contrast enhancement). Results . The study demonstrated that anaplastic astrocytomas are characterized by significantly low absolute and normalized hemodynamics parameters (BF, BV, PS) when compared with glioblastomas, and significantly low absolute maximum values of blood flow (BF) and blood volume (BV) when compared with the group of anaplastic oligodendrogliomas. CT perfusion using the normalized permeability index (PS) can reliably differentiate glioblastomas and anaplastic oligodendrogliomas. Perfusion parameters, both absolute and normalized, did not show statistically significant differences in the differential diagnosis of various molecular and genetic subtypes of anaplastic astrocytomas. Conclusion . CT perfusion using all hemodynamic parameters demonstrated high reliability and efficacy in distinguishing between glioblastomas and anaplastic astrocytomas. Further research is required to evaluate the effectiveness of the method in distinguishing glioblastomas from anaplastic oligodendrogliomas.

To study tissue characteristics of periventricular white matter in patients with open hydrocephalus using DWI MRI and their correlations with CSF flow parameters. MRI was performed in 55 patients (35 women and 20 men) with open normal pressure hydrocephalus, as well as 16 patients with malignant occlusive hydrocephalus and interstitial edema (control group). We determined the correlations between severity of hydrocephalus, periventricular lesions and CSF flow parameters considering MR data. Dimensions of ventricular system were assessed using the Evans' index, periventricular changes - using visual four-level scale with calculation of apparent diffusion coefficient (ADC) and fractional anisotropy coefficient (FA). Among patients with open hydrocephalus, ACD range for periventricular white matter was 1.57±0.15·10^-3 mm²/s in subgroup of patients without periventricular changes (n=29) and 1.62±0.11×10^-3 mm²/s in patients with periventricular changes (n=26). In the control group, mean ADC was 1.76±0.18·10^-3 mm²/s (p 0.4 (p<0.05). According to MR data, periventricular changes in patients with open hydrocephalus differ from true periventricular interstitial edema following occlusive hydrocephalus. Severity of periventricular changes in patients with open hydrocephalus depends on patient age and width of the ventricles, but does not correlate with CSF flow parameters. In our opinion, periventricular changes are associated with dysfunction of glymphatic system. Further research is required to study the functioning of glymphatic system and related processes.

ЦЕЛЬ ИССЛЕДОВАНИЯ Определить влияние анатомических особенностей и размеров латерального кармана с дефектом на выбор хирургического доступа и качество произведенной пластики. МАТЕРИАЛ И МЕТОДЫ Выполнен ретроспективный анализ компьютерных томограмм 38 пациентов, которым проведено хирургическое лечение в ФГАУ «НМИЦ нейрохирургии им. акад. Н.Н. Бурденко» Минздрава России по поводу дефектов основания черепа в области латерального кармана клиновидной пазухи. Пациенты разделены на три группы: в зависимости от применяемого доступа (1-я группа), частоты рецидивов (2-я группа) и особенностей интраоперационной визуализации дефекта (3-я группа). РЕЗУЛЬТАТЫ В анатомических особенностях у пациентов, которым выполняли транскрылонебный и транссфеноидальный доступ, а также у пациентов 2-й группы статистически значимые различия отсутствовали. У пациентов 3-й группы (с особенностями визуализации) отмечены статистически значимые различия между расстоянием от дефекта до линии VR (p=0,007). У пациентов с хорошей визуализацией дефекта с использованием прямой оптики это расстояние было меньше, чем у пациентов, дефект у которых визуализирован угловым эндоскопом. Другие анатомические различия при этом не отмечены. ВЫВОДЫ Анатомические особенности строения латерального кармана (вид пневматизации, размеры и объем) не оказывали влияния на выбор доступа к дефекту и на частоту возникновения рецидивов. При сравнении доступов отмечено, что транскрылонебный доступ, обеспечивая прямую визуализацию дефектов, сводит к минимуму риск развития рецидивов в послеоперационном периоде. Объективным анатомическим показателем для выбора доступа к дефектам латерального кармана может служить расстояние от дефекта до линии VR: при расстоянии более 0,7 см целесообразно выполнять транскрылонебный доступ, при расстоянии менее 0,7 см можно добиться прямой визуализации дефекта и выполнения качественной пластики с транссфеноидальным доступом.

КЛИНИЧЕСКАЯ ХАРАКТЕРИСТИКА И ДИФФЕРЕНЦИАЛЬНАЯ ДИАГНОСТИКА КЛАССИЧЕСКИХ ПАРАНЕОПЛАСТИЧЕСКИХ НЕВРОЛОГИЧЕСКИХ СИНДРОМОВ ПРИ ЛИМФОМАХ