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To determine blood volume flow (BVF) in the brain-supplying arteries in patients with fibromuscular dysplasia (FMD), we used two-dimensional cine phasecontrast MR blood flow quantification to evaluate haemodynamic compromise. Nine patients with angiographically proven FMD (mean age, 46.7 ± 10.4 years) of the cervical and intracranial arteries were examined using two-dimensional phase contrast MR to measure blood flow in the carotid arteries and the basilar artery (BA). Quantitative BVF results were compared intra- and inter-individually and also with the results of 15 age- matched normal controls. No patient showed evidence of acute or chronic infarction of the brain. FMD lesions were found in a total of 19 arteries (internal carotid artery: n = 14; vertebral arteries: n = 5). Five patients demonstrated severe stenoses of cervical vessels; four patients showed only mild or up to moderate stenoses. Total brain BVF in all FMD patients reached high-normal values compared with normal controls (747±64 ml min-1 vs 682±38 ml min-1). In the five patients with severe stenotic lesions, blood flow was reduced in stenotic vessels and higher in the nonhaemodynamically relevant stenosed cervical vessels. BVF was normal in the four patients with mild and moderate stenoses. By quantifying blood flow, we demonstrated for the first time changes (which can be severe) in the BVF of the brainsupplying arteries in FMD. Individual differences are associated with the haemodynamic relevance of the FMD lesions. Total BVF in patients with severe FMD was not decreased but maintained or even increased, possibly as an overcompensation. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is two-fold. First, to evaluate, whether functional rectal MRI techniques can be analyzed in a reproducible manner by different readers and second, to assess whether different clinical and pathologic T and N stages can be differentiated by functional MRI measurements.Materials and Methods: 54 patients (38 men, 16 female; mean age 63.2 ± 12.2 years) with pathologically proven rectal cancer were included in this retrospective IRB-approved study. All patients were referred for a multi-parametric MRI protocol on a 3 Tesla MR-system, consisting of a high-resolution, axial T2 TSE sequence, DWI and perfusion imaging (plasma flow -s PFTumor) prior to any treatment. Two experienced radiologists evaluated the MRI measurements, blinded to clinical data and outcome. Inter-reader correlation and the association of functional MRI parameters with c- and p-staging were analyzed.Results: The inter-reader correlation for lymph node (ρ 0.76-0.94; p<0.0002) and primary tumor (ρ 0.78-0.92; p<0.0001) apparent diffusion coefficient and plasma flow (PF) values was good to very good. PFTumor values decreased with cT stage with significant differences identified between cT2 and cT3 tumors (229 versus 107.6 ml/100ml/min; p=0.05). ADCTumor values did not differ significantly. No substantial discrepancies in lymph node ADCLn values or short axis diameter were found among cN1-3 stages, whereas PFLn values were distinct between cN1 versus cN2 stages (p=0.03). In the patients without neoadjuvant RCT no statistically significant differences in the assessed functional parameters on the basis of pathologic stage were found.Conclusion: This study illustrates that ADC as well as MR perfusion values can be analyzed with good interobserver agreement in patients with rectal cancer. Moreover, MR perfusion parameters may allow accurate differentiation of tumor stages. Both findings suggest that functional MRI parameters may help to discriminate T and N stages for clinical decision making. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the correlation between maximum standardized uptake value (SUV(max)) of (18)FDG PET-CT and iodine-related attenuation (IRA) of dual energy CT (DECT) of primary tumours and (18)FDG PET-CT positive thoracic lymph nodes (LN) in patients with lung cancer.Methods: 37 patients with lung cancer (27 NSCLC, 10 SCLC, 86 (18)FDG PET-CT positive thoracic LN) who underwent both (18)FDG PET-CT and DECT were analyzed. The mean study interval between (18)FDG PET-CT and DECT was ≤21 days in 17 patients. The mean and maximum IRA of DECT as well as of virtual unenhanced and virtual 120 kV images of DECT was analyzed and correlated to the SUV(max) of (18)FDG PET-CT in all tumours and (18)FDG PET-CT positive thoracic lymph nodes. Further subgroup analysis was performed for histological subtypes in all groups.Results: A moderate correlation was found between SUV(max) and maximum IRA in all tumours (n = 37;r = 0.507;p = 0.025) whereas only weak or no correlation were found between SUV(max) and all other DECT measurements. A strong correlation was found in patients with study intervals ≤21 days (n = 17; r = 0.768;p = 0.017). Analysis of histological subtypes of lung cancer showed a strong correlation between SUV(max) and maximum IRA in the analysis of all patients with NSCLC (r = 0.785;p = 0.001) and in patients with NSCLC and study intervals ≤21 days (r = 0.876;p = 0.024). Thoracic LN showed moderate correlation between SUV(max) and maximum IRA in patients with study intervals ≤21 days (r = 0.654; p = 0.010) whereas a weak correlation was found between SUV(max) and maximum IRA in patients with study intervals >21 days (r = 0.299; p = 0.035).Conclusions: DECT could serve as a valuable functional imaging test for patients with NSCLC as the IRA of DECT correlates with SUV(max) of (18)FDG PET-CT. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate a whole body (WB) continuous-table-movement (CTM) MR protocol for the assessment of multiple myeloma (MM) in comparison to a step-by-step WB protocol.Methods: Eighteen patients with MM were examined at 1.5T using a WB CTM protocol (axial T2-w fs BLADE, T1-w GRE sequence) and a step-by-step WB protocol including coronal/sagittal T1-w SE and STIR sequences as reference. Protocol time was assessed. Image quality, artefacts, liver/spleen assessability, and the ability to depict bone marrow lesions less than or greater than 1 cm as well as diffuse infiltration and soft tissue lesions were rated. Potential changes in the Durie and Salmon Plus stage and the detectability of complications were assessed.Results: Mean protocol time was 6:38 min (CTM) compared to 24:32 min (standard). Image quality was comparable. Artefacts were more prominent using the CTM protocol (P = 0.0039). Organ assessability was better using the CTM protocol (P < 0.001). Depiction of bone marrow and soft tissue lesions was identical without a staging shift. Vertebral fractures were not detected using the CTM protocol.Conclusions: The new protocol allows a higher patient throughput and facilitates the depiction of extramedullary lesions. However, as long as vertebral fractures are not detectable, the protocol cannot be safely used for clinical routine without the acquisition of an additional sagittal sequence. [ABSTRACT FROM AUTHOR]