Search

Surgery is the only potentially curative treatment of pancreatic cancer. Imaging methods, especially computed tomography (CT), play an essential role in the detection and staging of pancreatic cancer. The primary CT finding determines the treatment strategy, namely the resectability of the cancer with a potentially curative outcome. Imaging (CT) assessments are important also throughout oncological treatment of the patients and after the surgery, as well. Our paper summarizes the current state of the art of computed tomography and magnetic resonance imaging in pancreatic cancer, including a structured CT report proposal in pancreatic cancer.

Background: Gadolinium brain deposits after intravenous application of gadolinium-based contrast agents (GBCA) have been recently reported., Aim: We focused selectively on gadoxetate disodium, a hepatospecific linear GBCA. There are currently only a few studies in peer-reviewed literature focused selectively on gadoxetate disodium with conflicting results., Materials and Methods: Twenty patients (mean age 55.5 ± 14.0 years) after previous repeated administrations of gadoxetate disodium (mean 2.6 ± 1.5) for liver diagnostic process were included. All patients had normal renal and liver functions, an intact blood-brain barrier, and did not receive any other GBCA. They underwent 26 brain magnetic resonance imaging (MRI) with T1WI axial scans for signal intensity (SI) evaluation. The SI changes were measured in globus pallidus (GP), dentate nucleus (DN), pons (Po), and thalamus (Th) and SI ratios (DN/Po, GP/Po, GP/Th, Th/Po) were calculated. The control group consisted of 10 healthy volunteers (mean age 54.8 ± 12.1 years) with no prior GBCA applications., Statistical Analysis: Robust linear regression was used to test the effect of number of applications on the SI ratios., Results: The significant effect of number of gadoxetate previous applications on DN/Po SI ratio was found. On an average, the DN/Po ratio increased by 0.36 percentage points [P = 0.042, 95% CI (0.03, 0.69)]. Other SI ratios were not significantly affected., Conclusions: Repeated administrations of hepatospecific gadoxetate disodium leads to a statistically significant increase in the SI values in DN in patients with normal renal and liver functions, and with an intact blood-brain barrier, probably due to gadolinium deposition., Competing Interests: There are no conflicts of interest

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.

Background: Radiosurgery by Gamma Knife (GK) is an effective treatment for brain arteriovenous malformations (AVM). The aim of the present study was to evaluate late, radiation-induced changes detectable by MRI after AVM radiosurgery in patients treated minimally 10 years prior, with AVM obliteration proven by angiography., Methods: Thirty-five patients with 37 AVMs were included. AVMs were irradiated 16.6 ± 3.5 years prior with AVM obliteration proven 13 ± 4 years prior. All patients underwent recent MRI examinations, including application of gadolinium-based contrast., Results: In one case, post-irradiative cystic formation with mass effect and signs of hemorrhage requiring surgery was found. Post-gadolinium enhancement at the site of obliterated nidi was apparent in 28 of 37 cases (76 %). In all cases except one, the mean volume of enhancement at the time of review was clearly lower than the volume of the originally irradiated AVM (88 ± 20 %; median 92 %); in one case the extent was 142 % greater than the irradiated AVM. When we compared enhancing and non-enhancing nidi, we found that enhancing nidi were significantly larger than non-enhancing nidi at the time of radiosurgery (4.39 ± 3.35 cc vs. 0.89 ± 0.79 cc, p = 0.004). Enhancement was not influenced by total radiation dose, patient age at the time of irradiation, duration since radiosurgery, or the number of irradiations. Wallerian degeneration was found in nine of 37 cases (24 %); in six cases the optical tracts were affected and visual field defects were proven. In five of nine cases (55.6 %) with Wallerian degeneration previous hemorrhage was present. Dual vascular pathology was found in eight of 35 patients (23 %)., Conclusions: GK radiosurgery for AVM is a safe treatment method although delayed complications may occur. Post-gadolinium enhancement of obliterated nidi may indicate an active post-irradiative process.

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., (© 2015 by American Journal of Neuroradiology.)

Aims: Our aim was to evaluate the potential for safely imaging patients with a new type of implantable cardioverter-defibrillator called the subcutaneous implantable cardioverter-defibrillator (S-ICD) in a 1.5 T magnetic resonance imaging (MRI) scanner. With the increasing number of patients with cardiac implantable devices who are indicated for MRI, there is a growing need for establishing MRI compatibility of cardiac implantable devices., Methods and Results: Patients with implanted S-ICD systems underwent one or more types of anatomical MRI scans. The S-ICD was programmed off and patients were monitored throughout the imaging procedure. Device function was evaluated pre- and post-scan. Patients were asked to report immediately any pain, torqueing movement, or heating sensation in the area of the pocket or electrode. Fifteen patients underwent a total of 22 examinations at 1.5 T. Scans included brain, spine, knee, and heart. Two patients were re-scanned due to complaints of heating over the can during lumbar scans, which was caused by a thermistor probe placed on the skin to measure skin temperature. All the remaining scans occurred without incident. No evidence of device malfunction was observed., Conclusion: This study is the first to domonstrate the feasibility of exposing S-ICD patients to MRI using the scanning and monitoring protocol described. More data are required to support S-ICD as a MRI conditional device., (© The Author 2015. Published by Oxford University Press on behalf of the European Society of Cardiology.)

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.