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To describe the added value of novel functional MRI techniques towards detection, staging, characterization, response monitoring and prognostication in gynaecological cancer.Functional MRI including diffusion-weighted imaging (DWI)-MRI and dynamic contrast-enhanced (DCE)-MRI adds structural, hemodynamic and physiological information to anatomical MRI. In endometrial and cervical cancer, the addition of DWI-MRI and DCE-MRI improves tumour detection as well as staging of uterine and extra-uterine pelvic spread. Quantitative assessment of DWI and DCE-MRI reflecting tissue properties of biological aggressiveness or treatment resistance may enable the prediction of risk of extra-uterine or extra-ovarian disease spread, predict risk of recurrence and assess treatment response. DWI shows high accuracy for detecting peritoneal metastases and allows for comprehensive staging of (recurrent) ovarian cancer following the clinical development of whole body DWI-MRI.The added value of DWI/DCE-MRI for characterization and staging of gynaecological malignancy is becoming increasingly established and may improve treatment stratification. Ongoing multicentre studies are expected to further consolidate its use in clinical routine. Quantitative evaluation of functional MRI may help in prognostication and risk stratification.

To compare a commercial contrast agent (CA) Dotarem and a necrosis-avid CA (NACA) for their ability to evaluate the therapeutic necrosis with a vascular disrupting agent (VDA) on magnetic resonance imaging in rodent liver tumors to determine which could better correlate with the histopathologic outcome.: After the VDA treatment, 16 rats with 32 liver rhabdomyosarcomas were randomized into Dotarem and NACA groups (n = 8 per group) for both interindividual and intraindividual comparisons. T2-weighted imaging, T1-weighted imaging (T1WI), contrast-enhanced T1-weighted imaging (CE-T1WI), and diffusion-weighted imaging were performed at baseline, after VDA treatment and CA injections. The enhancing efficacy of CAs at immediate and delayed enhancement on CE-T1WI in viable tumor and necrosis was compared. Tumor necrosis ratios calculated from NACA and Dotarem were compared and correlated with gold-standard histopathology.: On the immediate CE-T1WI, viable tumor was enhanced by either CA. On the delayed CE-T1WI at 30 minutes, both CAs failed to demarcate viable tumor from necrosis. At 24 hours post-NACA, the necrosis was clearly distinguished from viable tumor and thus derived necrosis ratio matched that from histopathology (P = 0.99); necrosis ratio from Dotarem was significantly lower than that from NACA and histopathology (P0.05, both), with a higher correlation of NACA than that of Dotarem with histopathology (r = 0.99 vs. r = 0.82).: NACA better evaluated VDA-induced tumor necrosis than nonspecific CA on T1WI in tumor models of rat liver. NACA showed a closer correlation with histopathology than nonspecific CA for the delineation of true necrosis. Delayed enhancement on T1WI with nonspecific CA is not suitable for the assessment of VDA-induced tumor necrosis.

OBJECTIVES: To document tumoricidal events after intravenous administration of a vascular targeting agent combretastatin A-4-phosphate (CA4P) in rodent liver tumors by using multiparametric magnetic resonance imaging (MRI) in correlation with microangiography and histopathology. MATERIALS AND METHODS: Thirty rhabdomyosarcomas of 8 to 14 mm in diameter were obtained 16 days after implantation in liver lobes of 15 rats. Using a 1.5T magnet and a 4-channel wrist coil, T2-weighted imaging (T2WI), pre- and postcontrast T1-weighted imaging (T1WI), diffusion-weighted imaging (DWI), and dynamic susceptibility imaging (DSI) with relative blood volume (rBV) and flow (rBF) maps were acquired at baseline, 1 hour, 6 hours, and 48 hours after iv injection of CA4P at 10 mg/kg and vehicle in 9 treated and 6 control rats, respectively. In vivo data including signal intensity (SI), tumor volume, apparent diffusion coefficient (ADC), rBV, and rBF were correlated with ex vivo microangiographic and histopathologic findings. RESULTS: CA4P-treated tumors (n = 18) grew slower than those (n = 12) of controls (P < 0.05), with vascular shutdown evident on CE-T1WI at 1 hour but more prominent at 6 hours. However, enhanced rim occurred in the periphery 48 hours after treatment, indicating neovascularization. ADC map enabled distinction between necrotic and viable tumors. DSI-derived tumoral rBV and rBF decreased significantly at 1 hour through 6 hours and partly recovered at 48 hours. SI-time curve reflected diverse therapeutic responses between tumor and liver. MRI findings were verified by ex vivo techniques. CONCLUSIONS: Clinical MRI allowed monitoring of CA4P-related vascular shutdown, necrosis, and neovascularization of liver tumors in rats. Single dose of CA4P seemed insufficient for tumor eradication because of evident peripheral residue and recurrence. ispartof: Investigative Radiology vol:44 issue:1 pages:44-53 ispartof: location:United States status: published

Objective We evaluated an automated polyp size measurement tool in computed tomographic colonography for its accuracy and value for patient risk stratification. Methods A simulation program generated a raw data phantom with sessile and pedunculated polyps of known sizes using 120 to 140 kV and 50, 40, 20, 15, and 10 mAs. All polyps were measured by clicking on the polyp surface. Comparison of the calculated size with the known polyp sizes allowed calculation of reproducibility and accuracy. For patients with proven polyps, we also compared automated measurements with manual and endoscopic measurements to evaluate the effect on patient risk stratification. Results The automated measurement tool allowed accurate measurements. In the patient study, assignment to the correct size group was not significantly different from the radiologist's results. However, it slightly improved patient risk stratification by reducing both failed and unnecessary colonoscopy referral. Conclusions An automated tool for polyp measurement in patients facilitates patient risk stratification.

Although fetal kidneys have only 10% of their postnatal blood flow, fetal renal development is essential for normal postnatal function. In addition, to our knowledge it is unknown whether human fetal kidney development follows a linear or exponential evolution. We created normative magnetic resonance imaging curves for the kidney prenatal growth pattern in relation to gestational age.A total of 142 human fetuses at between 20 and 36 weeks of gestation underwent prenatal magnetic resonance imaging for nonurological pathology (pulmonary, cerebral or maternal abnormalities). Twins, urinary tract abnormalities, oligohydramnios or anhydramnios were excluded. T2-weighted images (single shot turbo spin-echo) were used to measure kidney variables. Bipolar and anteroposterior diameters of the 2 kidneys were measured and correlated with gestational age using linear regression analysis.A linear relationship of the bipolar and anteroposterior diameters was found according to gestational age in weeks (p0.0001). No substantial differences between growth of the left and right fetal kidneys was identified. Bipolar length of the human fetal kidney increases at an average rate of 1.24 mm per week of gestation, while anteroposterior diameter increases at 0.57 mm per week of gestation between weeks 20 and 36. This indicates that bipolar diameter increases twice as rapidly as anteroposterior diameter. Regression analysis curves showed a good fit to the measured data points (anteroposterior and bipolar measurements R2 = 0.36 and 0.58, respectively). The CIs of function variables were small, enabling their use as normative curves.This prenatal magnetic resonance imaging study demonstrates linear growth of the bipolar and anteroposterior diameters of human fetal kidneys in relation to gestational age. In addition, it is clear that bipolar diameter grows twice as rapidly as anteroposterior diameter and there is less variability for bipolar diameter. These normative curves may allow us to detect abnormal fetal evolution.