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Incidentalomas of the parenchymal organs of the abdomen, i.e. radiological findings in these organs that are not the primary focus of the clinical question, are frequent in this region of the body. In particular, findings presumed to be unimportant, such as cystic masses in the liver, the bile duct system or the pancreas, initially appear to be irrelevant in the diagnosis. For the liver we define the mostly clearly diagnosable simple cysts and hemangiomas as leave me alone lesions. Otherwise, we recommend a classification of incidentalomas into the three major categories (<0.5 cm, 0.5-1.5 cm and >1.5 cm) as well as an assessment with respect to clearly benign and suspect imaging characteristics in the context of a classification of patients into three different risk groups., (© 2022. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Background/objectives: The aim of this study was to compare intravoxel incoherent motion (IVIM) diffusion weighted (DW) MRI and CT perfusion to assess tumor perfusion of pancreatic ductal adenocarcinoma (PDAC)., Methods: In this prospective study, DW-MRI and CT perfusion were conducted in nineteen patients with PDAC on the day before surgery. IVIM analysis of DW-MRI was performed and the parameters perfusion fraction f, pseudodiffusion coefficient D*, and diffusion coefficient D were extracted for tumors, upstream, and downstream parenchyma. With a deconvolution-based analysis, the CT perfusion parameters blood flow (BF) and blood volume (BV) were estimated for tumors, upstream, and downstream parenchyma. In ten patients, intratumoral microvessel density (MVD tumor ) and microvessel area (MVA tumor ) were analyzed microscopically in resection specimens. Correlation coefficients between IVIM parameters, CT perfusion parameters, and histological microvessel parameters in tumors were calculated. Receiver operating characteristic (ROC) analysis was performed for differentiation of tumors and upstream parenchyma., Results: f tumor significantly positively correlated with BF tumor (r = 0.668, p = 0.002) and BV tumor (r = 0.672, p = 0.002). There were significant positive correlations between f tumor and MVD tumor / MVA tumor (r ≥ 0.770, p ≤ 0.009) as well as between BF tumor and MVD tumor / MVA tumor (r ≥ 0.697, p ≤ 0.025). Correlation coefficients between f tumor and MVD tumor / MVA tumor were not significantly different from correlation coefficients between BF tumor and MVD tumor / MVA tumor (p ≥ 0.400). Moreover, f, BF, BV, and permeability values (PEM) showed excellent performance in distinguishing tumors from upstream parenchyma (area under the ROC curve ≥0.874)., Conclusions: The study shows that IVIM derived f tumor and CT perfusion derived BF tumor similarly reflect vascularity of PDAC and seem to be comparably applicable for the evaluation of tumor perfusion for tumor characterization and as potential quantitative imaging biomarker., Trial Registration: DRKS, DRKS00022227, Registered 26 June 2020, retrospectively registered. https://www.drks.de/drks&#95;web/navigate.do?navigationId=trial . HTML&TRIAL&#95;ID=DRKS00022227.

Background:  Radiological reports of pancreatic lesions are currently widely formulated as free texts. However, for optimal characterization, staging and operation planning, a wide range of information is required but is sometimes not captured comprehensively. Structured reporting offers the potential for improvement in terms of completeness, reproducibility and clarity of interdisciplinary communication., Method:  Interdisciplinary consensus finding of structured report templates for solid and cystic pancreatic tumors in computed tomography (CT) and magnetic resonance imaging (MRI) with representatives of the German Society of Radiology (DRG), German Society for General and Visceral Surgery (DGAV), working group Oncological Imaging (ABO) of the German Cancer Society (DKG) and other radiologists, oncologists and surgeons., Results:  Among experts in the field of pancreatic imaging, oncology and pancreatic surgery, as well as in a public online survey, structured report templates were developed by consensus. These templates are available on the DRG homepage under www.befundung.drg.de and will be regularly revised to the current state of scientific knowledge by the participating specialist societies and responsible working groups., Conclusion:  This article presents structured report templates for solid and cystic pancreatic tumors to improve clinical staging (cTNM, ycTNM) in everyday radiology., Key Points:   · Structured report templates offer the potential of optimized radiological reporting with regard to completeness, reproducibility and differential diagnosis.. · This article presents consensus-based, structured reports for solid and cystic pancreatic lesions in CT and MRI.. · These structured reports are available open source on the homepage of the German Society of Radiology (DRG) under www.befundung.drg.de.., Citation Format: · Persigehl T, Baumhauer M, Baeßler B et al. Structured Reporting of Solid and Cystic Pancreatic Lesions in CT and MRI: Consensus-Based Structured Report Templates of the German Society of Radiology (DRG). Fortschr Röntgenstr 2020; 192: 641 - 655., Competing Interests: The authors declare that they have no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

Introduction: To investigate whether MR-defecography can be employed in sensorimotor complete spinal cord injury (SCI) subjects as a potential diagnostic tool to detect defecational disorders associated with neurogenic bowel dysfunction (NBD) using standard parameters for obstructed defecation., Material and Methods: In a prospective single centre clinical trial, we developed MR-defecography in traumatic sensorimotor complete paraplegic SCI patients with upper motoneuron type injury (neurological level of injury T1 to T10) using a conventional 3T scanner. Defecation was successfully induced by eliciting the defecational reflex after rectal filling with ultrasonic gel, application of two lecicarbon suppositories and digital rectal stimulation. Examination was performed with patients in left lateral decubitus position using T2-weighted turbo spin echo sequence in the sagittal plane at rest (TE 89ms, TR 3220ms, FOV 300mm, matrix 512×512, ST 4mm) and ultrafast-T2-weighted-sequence in the sagittal plane with repeating measurements (TE 1.54ms, TR 3.51ms, FOV 400mm, matrix 256×256, ST 6mm). Changes of anorectal angle (ARA), anorectal descent (ARJ) and pelvic floor weakness were documented and measured data was compared to reference values of asymptomatic non-SCI subjects in the literature to assess feasibility., Results: MR-defecography provides evaluable imaging sequences of the induced evacuation phase in SCI patients. Measurement results for ARA, ARJ, hiatal width (H-line) and hiatal descent (M-line) deviate significantly from reference values in the literature in asymptomatic subjects without SCI. The overall mean values in our study for SCI patients were: ARA (rest) 127.3°, ARA (evacuation) 137.6°, ARJ (rest) 2.4cm, ARJ (evacuation) 4.0cm, H-line (rest) 7.6cm, H-line (evacuation) 8.1cm, M-line (rest) 2.6cm, M-line (evacuation) 4.2cm., Conclusions: MR-defecography is feasible in sensorimotor complete SCI patients. Individual MR-defecography findings may help to determine specific therapeutical options for respective patients suffering from severe NBD., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In addition to focal liver lesions, diffuse and vascular disorders of the liver represent a wide spectrum of liver diseases which are from the radiological point of view often difficult or nearly impossible to diagnose. Classical diagnostic methods are computed tomography and magnetic resonance imaging in addition to ultrasound. Diffuse parenchymal damage caused by diseases of various etiologies is therefore difficult to evaluate because it often lacks characteristic morphological features. For hepatic steatosis, hemochromatosis/siderosis as an example of a diffuse storage disease and sarcoidosis and candidiasis as infectious/inflammatory diseases, an image-based diagnosis is appropriate in some cases. For most diffuse liver diseases, however only nonspecific changes are visualized. Vascular pathologies of the liver, such as the Budd-Chiari syndrome and portal vein thrombosis, however, can usually be diagnosed very clearly using radiology and there is also a very effective interventional radiological treatment. Chronic diseases very often culminate in liver cirrhosis which is highly associated with an increased risk of liver cancer.

Background/aims: To retrospectively evaluate the morphologic characteristics of autoimmune pancreatitis (AIP) using MRI and CT., Methods: 86 dynamic contrast-enhanced CT and MRI scans in 36 AIP patients were evaluated regarding: different enlargement types, abnormalities of the main pancreatic duct (MPD), morphology of the parenchyma and other associated findings., Results: 3 types of enlargement were found: (1) a focal type (28%), (2) a diffuse type (involving the entire pancreas, 11%) and (3) a combined type (56%). The MPD was usually dilated together with focal or diffuse narrowing in 67% (24/36). Unenhanced MRI showed AIP area in 56% (mostly T(1) hypo- and T(2) hyperattenuating), and CT in 10% (hypoattenuating). The arterial phase depicted similar patterns for CT and MRI (hypoattenuating in 58 and 52%, respectively). Venous and late venous phase patterns were usually hyperattenuating in MRI (65 and 74%, late enhancement), while CT mostly showed no signal differences (isoattenuating in 57 and 75%), yielding significant differences between CT and MRI for the venous (p < 0.0001) and the late phase (p = 0.025). Miscellaneous findings were: rim sign (25%), pseudocysts (8%) and infiltration of large vessels (11%)., Conclusions: The 'late-enhancement' sign seems to be a key feature and is best detectable with MRI. MRI may be recommended in the diagnostic workup of AIP patients. and IAP., (Copyright © 2011 S. Karger AG, Basel.)

Purpose: To determine which of the quantitative parameters obtained from intravoxel incoherent motion diffusion weighted imaging (DWI) is the most significant for the differentiation between pancreatic carcinoma and mass-forming chronic pancreatitis., Materials and Methods: Twenty-nine patients with pancreatic masses were included, 9 proved to have a mass-forming pancreatitis and 20 had a pancreatic carcinoma. The patients were studied using intravoxel incoherent motion DWI with 11 b-values and the apparent diffusion coefficient (ADC), the true diffusion constant (D) and the perfusion fraction (f) were calculated. The diagnostic strength of the parameters was evaluated using receiver operating characteristic analysis., Results: The ADC in chronic pancreatitis was higher than in pancreatic carcinoma with significant differences at b = 50, 75, 100, 150, 200, 300 s/mm (ADC50 = 3.17 ± 0.67 vs. 2.55 ± 1.09, ADC75 = 2.46 ± 0.4 vs. 1.93 ± 0.52, ADC100 = 2.28 ± 0.48 vs. 1.73 ± 0.45, ADC150 = 1.97 ± 0.26 vs. 1.63 ± 0.40, ADC200 = 1.98 ± 0.24 vs. 1.53 ± 0.28, and ADC300 = 1.76 ± 0.19 vs. 1.46 ± 0.31 × 10(-3) mm2/s). No significant differences were found at b = 25, 400, 600, and 800 s/mm (ADC25 = 4.69 ± 0.65 vs. 4.04 ± 1.35, ADC400 = 1.57 ± 0.21 vs. 1.37 ± 0.30, ADC600 = 1.38 ± 0.18 vs. 1.24 ± 0.25, and ADC800 = 1.27 ± 0.10 vs. 1.18 ± 0.19 × 10(-3) mm2/s) nor using ADCtot (1.42 ± 0.23 vs. 1.28 ± 0.12 × 10(-3) mm2/s). The perfusion fraction f was significantly higher in pancreatitis compared with pancreatic carcinoma (16.3% ± 5.30% vs. 8.2% ± 4.00%, P = 0.0001). There was no significant difference between groups for D (1.07 ± 0.224 × 10(-3) mm2/s for chronic pancreatitis and 1.09 ± 0.3 × 10(-3) mm2/s for pancreatic carcinoma, P = 0.66). For f, the highest area under the curve (0.894) and combined sensitivity (80%) and specificity (89.9%) were found., Conclusions: There were significant differences in ADC50-300 between chronic pancreatitis and pancreatic carcinoma. Because D is not significantly different between groups, differences in ADC can be attributed mainly to differences in perfusion. The perfusion fraction f proved to be the superior DWI-derived parameter for differentiation of mass-forming pancreatitis and pancreatic carcinoma.

Purpose: High-resolution MR imaging of the layers of the gastrointestinal wall to provide a foundation for tumor staging based on morphological criteria., Materials and Methods: Over a period of 12 months, miscellaneous parts of the gastrointestinal tract of 15 human specimens and 30 porcine specimens were scanned using a 1.5 Tesla clinical MRI scanner combined with an endoluminal receiver coil. The sequences used were T 1-weighted opposed-phase, T 2-weighted turbo spin echo with fat saturation and fast T 2-weighted inversion recovery. The number of differentiable layers, their width and the signal intensity were documented. Then, the results were compared with histological specimens in order to link the imaged wall layers to the anatomical layers. Spearman's Rank Correlation was used to determine the soundness of the link between the images and their related histology., Results: For both human and animal specimens, the MRI scanning produced 3 to 5, maximum 6 (pig), differentiable layers. The mucosa, submucosa and muscularis could be differentiated with a hyperintense, hypointense and intermediary signal, respectively. The subserosal layer displayed a hypointense signal., Conclusion: High-resolution MRI is able to produce differentiable images of the anatomical layers of the gastrointestinal wall in both humans and pigs. Accordingly, it is possible to use MR imaging to diagnose the extent of local tumor infiltration of the gastrointestinal wall.

Purpose: To examine if standard magnetic resonance (MR) imaging of the axial skeleton is sufficient for evaluation of patients with multiple myeloma (MM) or monoclonal gammopathy of undetermined significance (MGUS) or if whole-body MR is necessary., Materials and Methods: A total of 100 untreated patients with MGUS (n = 27) or any stages of MM (n = 73) were examined with whole-body MR imaging and MR imaging of the axial skeleton. The study was approved by the institutional ethics committee, and written informed consent was given. Spinal pattern ("no diffuse involvement" or "diffuse involvement" as assessed from the signal intensity of the spinal bone marrow), serum parameters, and stage of disease were correlated with the probability of detecting extra-axial lesions with and without destruction of cortical bone by using a multiple logistic regression model., Results: Of 100 patients, 39 had lesions in the axial skeleton and 37 had lesions in the extra-axial skeleton. Of the latter group, nine patients had no axial lesions and 13 patients had lesions that violated cortical bone, which implied an increased fracture risk. Because of the extraaxial location, lesions in these patients could be diagnosed with whole-body MR only. In addition, no single or combination of clinical factors observed (stage of disease, serum parameters, and spinal pattern) allowed investigators to identify patients with a significantly increased probability of having extra-axial lesions or lesions violating cortical bone., Conclusion: Whole-body MR imaging has potential for use in the initial work-up of patients with MGUS or MM, since almost one-half of all observed lesions would have been missed by using spinal MR imaging only and clinical parameters could not exclude the presence of extra-axial lesions.

Purpose: To prospectively compare diagnostic parameters of a newly developed endoluminal MRI (endo-MRI) concept with endoscopic ultrasound (EUS) and hydro-computer tomography (Hydro-CT) in T-staging of gastric carcinoma on one patient collective., Material and Methods: 28 consecutive patients (11 females, 17 males, age range 46-87 years, median 67 years) referred for surgery due to a gastric malignancy were included. Preoperative staging by EUS was performed in 14 cases and by Hydro-CT in 14 cases within a time frame of 2 weeks. Ex vivo endo-MRI examination of gastric specimens was performed directly after gastrectomy within a time interval of 2-3h. EUS data were acquired from the clinical setting whereas Hydro-CT and endo-MRI data were evaluated in blinded fashion by two experienced radiologists and one surgeon well experienced in EUS on gastric carcinomas., Results: Histopathology resulted in 4 pT1, 17 pT2, 3 pT3 and 2 pT4 carcinomas with 2 gastric lymphomas which were excluded. Overall accuracy for endo-MRI was 75% for T-Staging of the 26 carcinomas. EUS achieved 42.9% accuracy; endo-MRI in this subgroup was accurate in 71.4%. Hydro-CT was correct in 28.6%, accuracy for endo-MRI in this subgroup was 71.4%., Conclusion: The direct comparison of all three modalities on one patient collective shows that endo-MRI is able to achieve adequate staging results in comparison with clinically accepted methods like EUS and Hydro-CT in classifying the extent of tumor invasion into the gastric wall. However the comparison is limited as we compared in vivo routine clinical data with experimental ex vivo data. Future investigations need to show if the potential of endo-MRI can be transferred into a clinical in vivo setting.

In the diagnosis of diseases of the esophagus, conventional x-ray evaluation still plays a more important role than endoscopy in the visualization of stenoses. CT plays a major role in the staging of malignancies of the esophagus, while MRI plays does not play a major part in the diagnostic evaluation of the upper GI-tract but is equal to CT for the staging and evaluation of the extent of local infiltration. The main indication for the radiological examination of the esophagus by barium studies is dysphagia. The use of barium allows a functional examination of esophageal motility. Swallow motility disorders can be diagnosed by videofluorography using high frame rate imaging. Zenker's diverticulum and other pulsion diverticula should also be investigated by functional esophageal imaging. Candida esophagitis can be identified by its characteristic ulcerations using barium swallow. The extension of gastroesophageal hernias are more accurately evaluated with barium studies than with endoscopy. The diagnosis of gastroesophageal reflux disease should be made by barium studies, but discrete inflammation as well as epithelial dysplasia are best investigated by classic endoscopy and modern endoscopic techniques. In cases of esophageal carcinoma, radiology adds to the findings of endoscopy and endosonography.

Objective: Preoperative staging of gastric carcinoma is limited by the fact that available imaging modalities do not enable accurate evaluation of the depth of infiltration of the gastric wall. The aim of this study was to evaluate the efficiency of conventional magnetic resonance imaging (MRI) in local staging of gastric carcinoma., Methods: Sixty-five specimens of patients with proven gastric carcinoma were examined immediately after gastrectomy. Examination was performed with a 1-T MRI and included T1-weighted, T2-weighted, and opposed phase images. Images were analyzed for the number of visible wall layers and their signal intensity characteristics, for tumor localization and depth of infiltration. T-stage was classified according to the TNM system. Finally, the staging by MRI was compared with the histopathological staging of the specimens., Results: The mucosal, submucosal, and proper muscle layers could be differentiated by the typical signal intensities. Depiction of the subserosa or serosa was not possible. In 65 specimens, 67 carcinomas were found by the pathologist. Sixty-four of 67 (96%) histologically proven carcinomas were correctly localized by MRI; T-staging accuracy was 50% only, mainly because of overstaging pT2 tumors as T3., Conclusions: MRI enables differentiation of gastric wall layers and, therefore, technically allows the evaluation of the local tumor stage of gastric carcinomas. However, infiltration of the subserosal and serosal layer cannot be proved accurately. Overstaging pT2 tumors is one of the most predominant problems. Yet further technical developments in high-resolution imaging of the gastric wall may improve T-staging in the near future and overcome today's staging limitations.

Our aim was to conduct a prospective study to evaluate staging accuracy of a new coil concept for endoluminal magnetic resonance imaging (MRI) on ex vivo gastric carcinomas. Twenty-eight consecutive patients referred to surgery with a clinically proven primary gastric malignancy were included. Surgical specimens were examined with a foldable and self-expanding loop coil (8-cm diameter) at 1.5 Tesla immediately after total gastrectomy. T1- and T2-weighted and opposed-phase sequences (axial, frontal sections; 3- to 4-mm slice thickness) were acquired. Investigators blinded to any patient information analyzed signal intensity of normal gastric wall, gastric tumor, and lymph nodes. Findings were compared with histopathological staging. On surgical specimens, 2-5 gastric wall layers could be visualized. All gastric tumors (26 carcinomas, two lymphomas) were identified on endoluminal MR data (100%). Overall accuracy for T staging was 75% (18/24); sensitivity to detect serosal involvement was 80% and specificity 89%. N staging correlated in 58% (14/24) with histopathology (N+ versus N-). The endoluminal coil concept is feasible and applicable for an ex vivo setting. Endoluminal MR data provided sufficient detail for gastric wall layer differentiation, and therefore, identification of T stages in gastric carcinoma is possible. Further investigations in in vivo settings should explore the potential of our coil concept for endoluminal MR imaging.

Purpose: Experimental feasibility study of a new MR-Coil concept for enhanced visualization of the gastric wall., Material and Methods: The newly developed single-loop receiver coil for endoluminal imaging (Fraunhofer Institute, St. Ingbert, Germany) was evaluated in 4 explanted pig stomachs in a 1.5T MR unit (Siemens Symphony, Erlangen, Germany) with T1 w and T2 w MR sequences in three planes. The new coil consists of a foldable and self-expanding single loop coil (receiver coil) of a shape memory metal (nitinol). It was covered with a biocompatible material (silicone) to prevent direct contact of the wire with stomach tissue. The coil assumes a circular configuration with a diameter of 8 cm because of its memory metal properties. The flexible characteristics of the material used allow the passage through the instrument channel (13 mm diameter) of a specially designed MR-compatible endoscope. The purpose of our study was to assess feasibility of the coil design as a first step in developing a new endoluminal MRI-concept. Additionally the number and signal intensity of visible gastric wall layers were evaluated and findings were correlated with histopathological results of a pig stomach., Results: The new coil concept was a feasible system in all 4 cases and showed good image quality for analysis. On T1 w images, 3 layers were visible in all cases, and on T2 w images 4 different gastric wall layers were seen in 2 cases. Due to histopathological correlation, the different gastric wall layers were identified as follows: mucosa, submucosa and muscularis propria if three layers were depicted; in cases of 4 visible wall layers, serosa and subserosa could be detected additionally. For each gastric wall layer, a distinct signal intensity was found., Conclusion: The new MR coil concept for endoluminal imaging proved to be a feasible technique. Good differentiation of gastric wall layers in the pig stomach could be demonstrated. We have shown that endoscopic MR-imaging with our new coil concept is a valuable technique for the visualization of gastric wall layers. Due to this fact, follow-up studies including assessing safety aspects are necessary to finally conduct an experimental-clinical study on in-vivo human gastric specimens to detect tumor growth and morphology within the gastric wall. Endoscopic MRI may have the potential in the future to overcome today's limitations of diagnostic imaging in gastric cancer.

Purpose: To evaluate multislice-CT versus MRI in the diagnosis and staging of pancreatic carcinoma in a prospective multi-reader analysis., Materials and Methods: Fifty patients with suspected pancreatic carcinoma underwent both multislice-CT (4-Row, "hydro-technique") and state-of-the-art MRI (two 1.5 T units). In correlation with histopathologic findings or in case of a non-lesion diagnosis by follow-up (6-month interval), we evaluated MRI versus CT in a multi-reader analysis (2 reader pairs) for: 1. diagnostic quality; 2. examination time; 3. accuracy of potential resectability; 4. kappa analysis of observer variations; and 5. overall diagnostic reliability., Results: A total of 28 lesions (n = 22 malignant, n = 6 benign) were present in the cohort group versus 22 patients without a focal lesion (n = 10 pancreatitis, n = 12 no tumor). For lesion detection, CT had a sensitivity of 100/89 % (reader pair 1/2) and specificity of 77 %, and MRI had a sensitivity of 75/89 % and specificity of 77/73 %. For the subgroup of adenocarcinomas of the pancreas (n = 17), we found a sensitivity of 100 % and a specificity of 61 % for CT versus a sensitivity of 82/94 % and a specificity of 67/61 % for MRI. The accuracy for determining the resectability was 91/82 % for CT and 90/82 % for MRI. The kappa analysis showed a good correlation for CT (0.71) and a moderate correlation of both groups for MRI (0.49)., Conclusion: CT and MRI showed comparable results in the detection of pancreatic carcinomas as well as in the determination of resectability. Chronic pancreatitis as a "tumor-like-lesion" was the major factor of a missed diagnosis. The results of multi-reader analysis for both reading groups were almost identical with a moderate to good kappa correlation. There is no reason to prefer MRI (more expensive) over CT for patients with the presumptive diagnosis of pancreatic cancer.

Purpose: To correlate gastric wall layers visible of MRI with the anatomical structure of the gastric wall., Methods: After macroscopic preparation 5 x 5 cm post-mortem tissue sections of the gastric antrum were evaluated using a 2.4 Tesla MR unit (Bruker, Ettlingen, Germany). MR imaging consisted of T2-weighted multi-spinecho sequences in longitudinal and axial directions. The specimens then were stained with hematoxylin-eosin for histological examination. After that histological correlation of the gastric wall layers visible on MRI was performed., Results: In all specimens four gastric wall layers could be clearly identified on MRI. The direct comparison of those layers to the histological findings showed the following correlation: 1) intermediate signal = mucosa, 2) hypointense signal = lamina muscularis mucosae, 3) hyperintense signal = submucosa, 4) intermediate signal = muscularis propria., Conclusions: Gastric wall layers visible on MRI were successfully correlated to the anatomic layers of the gastric wall. This allows us for the first time to classify invasion of gastric carcinoma using high spatial-resolution MR imaging. However, the subserosa and serosa are excluded from this conclusion, because so far a reliable statement concerning the value of MRI to depict these very variable layers is not possible.

Purpose: To compare thin-section hydro-CT and MRI in the detection of pancreatic neoplasms. Evaluation of an oral, superparamagnetic contrast agent (OMP) for pancreatic MRI., Material and Methods: 45 patients with suspected pancreatic neoplasms were examined with consecutive thin-section helical CT (Hydro-CT, 3/6/3, 130 ml Ultravist, Schering) and MRI (1.0 T, breath-holding, T1w-GRE, T1w-GRE fat-sat, T2w-TSE). The MRI protocol included precontrast studies, studies after oral administration of OMP (Abdoscan, Nycomed Amersham) and studies after administration of OMP and Gadodiamide i.v. (Omniscan, Nycomed Amersham). All images were assessed by two independent radiologists in a blinded fashion. Radiologic diagnosis was correlated with histology or clinical follow-up (> or = 3 month)., Results: 39 patients could be included in analysis. In 13 cases a pancreatic neoplasm was proven by histology. Thin-section hydro-CT and MRI showed no statistically significant differences for the detection of pancreatic neoplasia. The sensitivity of helical hydro-CT was superior compared to MRI (88.5% vs. 65.44/73.1%/76.9%). The specificity of MRI was superior compared to helical hydro-CT (86.5% vs. 94.2%/90.4%/88.5%)., Conclusion: Thin-section hydro-CT and MRI show similar results for the detection of pancreatic neoplasms. Compared to thin-section helical CT, MRI still has the drawbacks of much more time consumption and, still, lower spatial resolution. The use of an oral, superparamagnetic contrast agent added no advantage for pancreatic MRI.

Purpose: To describe the perfusion pattern of giant cell tumor (GCT) of bone with Gd-enhanced dynamic MR imaging. To compare time-intensity-curves in patients with local recurrence and postoperative alterations without recurrence., Methods: Nine patients (5 women, 4 men) with GCT of bone underwent 19 dynamic MRI examinations. Mean age was 34 years (range 24-64 years). All diagnoses were proven by pathology. Dynamic contrast-enhanced MRI was performed at 1.0 T using T1-weighted gradient echo sequences. GCT was located in the distal radius (4x), tibia (3x), fibula (1x) and humeral head (1x)., Results: All giant cell tumors showed a uniform perfusion pattern with a steep slope and maximum intensity value followed by an early and rapid washout phase. The same pattern appeared in five local recurrences of GCT in four patients. In nine follow-up examinations without local recurrence dynamic MRI yielded in uncharacteristic perfusion patterns., Conclusion: These results demonstrate a uniform perfusion pattern of GCT of bone obtained by dynamic MRI. It is characterized by a steep slope followed by an early and rapid washout phase. This characteristic pattern can also be obtained in local recurrences. Dynamic contrast-enhanced MRI appears a helpful method for primary diagnosis of GCT of bone and detection of local recurrences after surgery.