Review of the structural and functional brain changes associated with chronic kidney disease.

Chronic kidney disease (CKD) leads to profound metabolic and hemodynamic changes, which damage other organs, such as heart and brain. The brain abnormalities and cognitive deficit progress with the severity of the CKD and are mostly expressed among hemodialysis patients. They have great socio-economic impact. In this review, we present the current knowledge of involved mechanisms.

[Whole-Body CT Scan and Other Imaging Techniques in Examining Polytrauma Patients - Outcomes of a Questionnaire Survey of Trauma Centres in the Czech Republic]. / Celotelové CT a dalsí zobrazovací metody pri vysetrení pacienta s polytraumatem ­ výsledky dotazníkové studie mezi traumacentry v Ceské republice.

PURPOSE OF THE STUDY The study aimed to map the use of imaging techniques and results reporting in polytrauma patients by the trauma centres in the Czech Republic. MATERIAL AND METHODS The representatives of radiology departments and units of all 12 trauma centres in the Czech Republic completed a questionnaire regarding the imaging in polytrauma patients. RESULTS The Focused Assessment with Sonography for Trauma (FAST) as an initial imaging is used by all the centres, the WholeBody CT scan (WBCT) is the dominant imaging technique everywhere and all the centres have standards in place for its performance. The WBCT examination protocol varies across the centres, just like the evaluation procedures of the CT scan and reporting of the results over to the indicating physicians. In majority of centres, there is a high percentage of WBCT with normal findings. One of the centres which uses also X-rays as a part of imaging algorithm, reports a notably higher percentage of WBCT positive findings. DISCUSSION When considering the radiation dose, data and time necessary for WBCT, work required to assess the WBCT and a large number of negative findings, it is disputable whether in a number of cases the WBCT is a suitable method for polytrauma patient examination. Similar conclusions have been drawn also by other authors who recommend that the WBCT is always used for unconscious polytrauma patients, in whom a clinical examination is virtually impossible. In the other cases, based on the clinical parameters the other imaging techniques and the focused CT (and in the indicated cases also the wholebody CT) can be safely used. CONCLUSIONS he diagnostic procedure in a polytrauma patient is not uniform in trauma centres and even the procedure for urgent reporting of crucial WBCT findings to clinical physicians has not been standardised. In a number of cases the indication for WBCT seems to be unnecessary. A more careful consideration of indications for imaging examinations based on the clinical finding may reduce the radiation exposure of patients while maintaining the diagnostic accuracy. A structured report on WBCT in polytrauma is not used even though it is recommended by the European Society of Radiology. Key words:polytrauma, diagnostic imaging, Whole-Body Computed Tomography, structured report.

Can morphological MRI differentiate between primary central nervous system lymphoma and glioblastoma?

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a rare, aggressive brain neoplasm that accounts for roughly 2-6% of primary brain tumors. In contrast, glioblastoma (GBM) is the most frequent and severe glioma subtype, accounting for approximately 50% of diffuse gliomas. The aim of the present study was to evaluate morphological MRI characteristics in histologically-proven PCNSL and GBM at the time of their initial presentation. METHODS: We retrospectively evaluated standard diagnostic MRI examinations in 54 immunocompetent patients (26 female, 28 male; age 62.6 ± 11.5 years) with histologically-proven PCNSL and 54 GBM subjects (21 female, 33 male; age 59 ± 14 years). RESULTS: Several significant differences between both infiltrative brain tumors were found. PCNSL lesions enhanced homogenously in 64.8% of cases, while nonhomogeneous enhancement was observed in 98.1% of GBM cases. Necrosis was present in 88.9% of GBM lesions and only 5.6% of PCNSL lesions. PCNSL presented as multiple lesions in 51.9% cases and in 35.2% of GBM cases; however, diffuse infiltrative type of brain involvement was observed only in PCNSL (24.1%). Optic pathways were infiltrated more commonly in PCNSL than in GBM (42.6% vs. 5.6%, respectively, p <0.001). Other cranial nerves were affected in 5.6% of PCNSL, and in none of GBM. Signs of bleeding were rare in PCNSL (5.6%) and common in GBM (44.4%); p < 0.001. Both supratentorial and infratentorial localization was present only in PCNSL (27.7%). Involvement of the basal ganglia was more common in PCNSL (55.6%) than in GBM (18.5%); (p < 0.001). Cerebral cortex was affected significantly more often in GBM (83.3%) than in PCNSL (51.9%); mostly by both enhancing and non-enhancing infiltration. CONCLUSION: Routine morphological MRI is capable of differentiating between GBM and PCNSL lesions in many cases at time of initial presentation. A solitary infiltrative supratentorial lesion with nonhomogeneous enhancement and necrosis was typical for GBM. PCNSL presented with multiple lesions that enhanced homogenously or as diffuse infiltrative type of brain involvement, often with basal ganglia and optic pathways affection.

The Benefits of High Relaxivity for Brain Tumor Imaging: Results of a Multicenter Intraindividual Crossover Comparison of Gadobenate Dimeglumine with Gadoterate Meglumine (The BENEFIT Study).

BACKGROUND AND PURPOSE: Gadobenate dimeglumine (MultiHance) has higher r1 relaxivity than gadoterate meglumine (Dotarem) which may permit the use of lower doses for MR imaging applications. Our aim was to compare 0.1- and 0.05-mmol/kg body weight gadobenate with 0.1-mmol/kg body weight gadoterate for MR imaging assessment of brain tumors. MATERIALS AND METHODS: We performed crossover, intraindividual comparison of 0.1-mmol/kg gadobenate with 0.1-mmol/kg gadoterate (Arm 1) and 0.05-mmol/kg gadobenate with 0.1-mmol/kg gadoterate (Arm 2). Adult patients with suspected or known brain tumors were randomized to Arm 1 (70 patients) or Arm 2 (107 patients) and underwent 2 identical examinations at 1.5 T. The agents were injected in randomized-sequence order, and the 2 examinations were separated by 2-14 days. MR imaging scanners, imaging sequences (T1-weighted spin-echo and T1-weighted high-resolution gradient-echo), and acquisition timing were identical for the 2 examinations. Three blinded readers evaluated images for diagnostic information (degree of definition of lesion extent, lesion border delineation, visualization of lesion internal morphology, contrast enhancement) and quantitatively for percentage lesion enhancement and lesion-to-background ratio. Safety assessments were performed. RESULTS: In Arm 1, a highly significant superiority (P < .002) of 0.1-mmol/kg gadobenate was demonstrated by all readers for all end points. In Arm 2, no significant differences (P > .1) were observed for any reader and any end point, with the exception of percentage enhancement for reader 2 (P < .05) in favor of 0.05-mmol/kg gadobenate. Study agent-related adverse events were reported by 2/169 (1.2%) patients after gadobenate and by 5/175 (2.9%) patients after gadoterate. CONCLUSIONS: Significantly superior morphologic information and contrast enhancement are demonstrated on brain MR imaging with 0.1-mmol/kg gadobenate compared with 0.1-mmol/kg gadoterate. No meaningful differences were recorded between 0.05-mmol/kg gadobenate and 0.1-mmol/kg gadoterate.

[Initial experience with magnetic resonance cholangiopancreatography]. / Nase první zkusenosti s magneticko-rezonancní cholangiopankreatikografií.

BACKGROUND: Magnetic resonance cholangiopancreaticography (MRCP) is based on heavily weighted T2 sequences (ETSE--echo-train spin echo) with suppression of fat, giving visualisation of slowly flowing or stagnating fluid. MRCP are short sequences in coronary plane with thickness of 8 cm or 4 mm. Retrospective analysis of all MRCP examinations performed during last 12 months is presented. METHODS AND RESULTS: Eighty-eight examinations were done, of which 67 ones with both adequate technical quality and clinical indication were included into the study (20 males aged 25-83 years, 47 women aged 19-82 years). Patients were divided into 4 groups regarding to the indications (group I.--temporary cholestasis, normal abdominal ultrasound, II.--definite cholestasis, III.--pathologic findings on pancreas, IV.--other). Vast majority of patients were included into group I (35 subjects). In 7 (20%) of them choledocholithiasis and/or stenoses (including multiple stenoses in primary sclerotizing cholangoitis) were found. MRCP brought diagnostic information in subjects with cholestasis (group II.) and answered questions given by clinicians. However, in 1 of 4 subjects with primary sclerotizing cholangoitis, MRCP did not reveal intra-hepatic stenoses, which were later visualised by classical ERCP. Only the extrahepatic stenoses were diagnosed by MRCP in the latter subject. CONCLUSIONS: MRCP should become a standard examination in the diagnostic algorithm in patients with cholangiopathies. MRCP has its value not only in subjects with unsuccessful or contraindicated ERCP, but also in subjects with temporary cholestasis with negative ultrasound finding.