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Purpose: To investigate the role of multiparametric magnetic resonance (MR) imaging in the evaluation of response to platinum-based neoadjuvant chemotherapy in advanced ovarian cancer and to compare imaging parameters between primary ovarian mass and metastatic disease., Materials and Methods: Evaluable patients suspected of having advanced ovarian carcinoma were enrolled in a prospective protocol-driven study. Research ethics committee approval and written informed consent were obtained. Multiparametric MR imaging (diffusion-weighted MR imaging, dynamic contrast material-enhanced [DCE] MR imaging, and hydrogen 1 MR spectroscopy) was performed with a 3.0-T wholebody MR imaging system. Three marker lesions-primary ovarian mass, omental cake, and peritoneal deposit-were outlined by a radiologist on apparent diffusion coefficient (ADC) and vascular signal fraction (VSF) maps and on DCE MR images. Comparisons of mean ADC, mean VSF, DCE MR imaging parameters, and choline concentration between responders and nonresponders were based on Response Evaluation Criteria in Solid Tumors and CA-125 criteria., Results: Twenty-two patients were evaluable. The mean ADC for peritoneal metastases was lower than that for ovarian (P = .015) and omental (P = .006) sites. There were no differences in pretreatment DCE MR imaging parameters between tumor sites. After treatment, responders showed a significantly larger increase in ADC (P = .021) and fractional volume of the extravascular extracellular space (v(e)) (P = .025) of ovarian lesions compared with nonresponders, but there was no change in ADC at other sites. Pre- and posttreatment values of choline concentration of ovarian lesions were lower in responders (P = .025) than in nonresponders (P = .010)., Conclusion: The significant differences in baseline ADCs among primary ovarian cancer, omental cake, and peritoneal deposits indicate that diffusivity profiles may be tumor-site dependent, suggesting biologic heterogeneity of disease. ADC and v(e) parameters correlated with the cytotoxic effects of platinum-based therapy and may be useful response markers, while choline concentration predicted but did not reflect response., (© RSNA, 2012.)

This study did not require ethical approval in the United Kingdom. The aim of this work was to create two controllers for navigating a two-dimensional image plane through a volumetric data set, providing two important features of the ultrasonographic paradigm: orientation matching of the navigation device and the desired image plane in the three-dimensional (3D) data and a constraining surface to provide a nonvisual reference for the image plane location in the 3D data. The first constrained surface controller (CSC) uses a planar constraining surface, while the second CSC uses a hemispheric constraining surface. Ten radiologists were asked to obtain specific image reformations by using both controllers and a commercially available medical imaging workstation. The time taken to perform each reformatting task was recorded. The users were also asked structured questions comparing the utility of both methods. There was a significant reduction in the time taken to perform the specified reformatting tasks by using the simpler planar controller as compared with a standard workstation, whereas there was no significant difference for the more complex hemispheric controller. The majority of users reported that both controllers allowed them to concentrate entirely on the reformatting task and the related image rather than being distracted by the need for interaction with the workstation interface. In conclusion, the CSCs provide an intuitive paradigm for interactive reformatting of volumetric data., ((c) RSNA, 2009.)

Purpose: To evaluate the effect of magnetic resonance (MR) imaging of the wrist on clinicians' diagnoses, diagnostic certainty, and patient care., Materials and Methods: A controlled observational study was performed. Referring clinicians completed questionnaires about diagnosis and intended management before and after wrist MR imaging. One hundred eighteen consecutive patients referred for MR imaging of the wrist were recruited from the MR imaging units at a regional teaching hospital and a large district general hospital. The main measures were changes in the clinicians' leading and subsidiary diagnoses after MR imaging, their certainty in these diagnoses, and changes in intended patient care., Results: Questionnaires were incorrectly completed for five patients, questionnaires were not returned for three, appointments were canceled for 10, and two could not tolerate the MR examination. Complete follow-up data were available for 98 patients. The clinical diagnosis changed in 55 of 98 patients; in the remaining 43 patients, diagnostic certainty increased in 23. Clinicians reported that MR imaging had substantially improved their understanding of the disease in 67 of 98 patients. The care plan changed in 45 of 98 patients, with a shift away from surgical treatment. Twenty-eight patients were discharged without further investigation. MR imaging was similarly effective in the regional teaching center and the district general hospital., Conclusion: MR imaging of the wrist influences clinicians' diagnoses and management plans.

Prior to surgery, seven patients with known colonic tumors underwent breath-hold single-shot fast spin-echo magnetic resonance imaging during a CO2 enema. The images were evaluated for depiction of tumor, adjacent structures, and the remaining colon, and findings were compared with findings at surgery. In all seven patients, the tumor was demonstrated, and in four (57%), breach of the muscularis propria was correctly predicted.

Purpose: To develop a noninvasive method for demonstrating the main salivary gland duct systems., Materials and Methods: The authors developed a magnetic resonance (MR) imaging protocol that uses a heavily T2-weighted (echo time, 750 msec), fat-suppressed pulse sequence and rapid acquisition with relaxation enhancement. The technique was optimized to depict fluid within a two-dimensional thick slab. A preliminary evaluation was performed by examining the major salivary gland ducts in 10 asymptomatic volunteers and three symptomatic patients with known salivary duct abnormalities., Results: The main parotid gland ducts were clearly demonstrated in all volunteers. The submandibular ducts were visible in all cases, although not always on projection images. In the three patients, the MR technique clearly demonstrated bilateral sialectasis, a calculus obstructing the left submandibular duct, and a fluid-filled ranula, respectively., Conclusion: Preliminary work indicates that this MR technique can successfully demonstrate both normal and abnormal parotid and submandibular gland duct systems and has several advantages over conventional x-ray sialography.

Purpose: To evaluate a breath-hold fast spin-echo (SE) technique for T2-weighted magnetic resonance (MR) imaging of liver lesions., Materials and Methods: A fast SE technique was developed that enabled six sections to be imaged per 16-second breath hold with a single echo. Resulting images were compared with those obtained with the first echo of a conventional dual-echo T2-weighted SE sequence (16 minutes 55 seconds for 18 sections). Thirty-one patients with malignant focal hepatic lesions were studied prospectively. The images were compared quantitatively and qualitatively., Results: Quantitatively, the contrast and contrast-to-noise ratios for the fast SE images were 20% +/- 5 and 19% +/- 8 greater, respectively, than those for the conventional T2-weighted SE images of the 54 representative lesions. Qualitatively, fast SE images had less image artifact, enabled comparable or better lesion sizing, and greatly improved depiction of extrahepatic structures compared with conventional T2-weighted SE images., Conclusion: The fast SE technique with breath holding provides diagnostically useful liver images in a greatly decreased acquisition time.