Dynamic MRI is useful for distinguishing high-flow from low-flow vascular malformations, especially when the contrast rise time of the lesion is measured.

Asymmetric dilatation of the RIPA as an indicator of extrahepatic collateral of HCC can be demonstrated on the right diaphragmatic crus with arteriographic images of biphasic helical CT.

BACKGROUND AND PURPOSE: MR imaging findings of LYH and pituitary adenomas are similar, but the therapeutic strategies are completely different. The purpose of this study was to evaluate sellar and parasellar MR imaging findings in patients with both diseases, as well as characteristic clinical findings.

Nipple discharge is a common symptom that mostly results from benign conditions. The most significant cause is carcinoma, which accounts for 1%-45% of cases. Therefore, identification of intraductal lesions is important. Conventional ductography, the recommended method of identifying lesions, is invasive and has inherent limitations. Magnetic resonance (MR) ductography is performed with heavily T2-weighted sequences; it is noninvasive and requires neither radiation nor contrast media. Like conventional ductography, MR ductography shows the dilated ducts as tubular structures with high signal intensity. Intraductal lesions appear as a signal defect, duct wall irregularity, or ductal obstruction. No specific conventional ductographic or MR ductographic finding allows differentiation between benign and malignant disease, and neither technique can demonstrate the extent of disease. MR mammography with intravenous injection of contrast material reveals the extent of disease, and a dynamic study may help distinguish between malignant and benign lesions. Fusion imaging with MR ductography and MR mammography demonstrates not only the presence of an intraductal abnormality but also the extent of the lesion on one image, thus clearly showing the relationship between the dilated duct and the intraductal lesion.

Purpose:To evaluate morphological and signal intensity (SI) changes of placental insufficiency on magnetic resonance imaging (MRI) and to assess morphological changes and decreased flow voids (FVs) on T2-weighted rapid acquisition with relaxation enhancement (RARE) images for diagnosing placental insufficiency.Methods:Fifty singleton fetuses underwent MRI using a 1.5-T MR scanner. Placental thickness, area, volume, SI, amniotic fluid SI, and size of FVs between the uterus and the placenta were measured on MR images. Two radiologists reviewed T2-weighted RARE images for globular appearance of the placenta and FVs between the uterus and the placenta. Data were analyzed using t-tests, McNemar’s tests, and areas under the receiver operating characteristic curve (AUCs) at 5% level of significance.Results:Twenty-five of the 50 pregnancies were categorized as having an insufficient placenta. Significant differences were observed between insufficient and normal placentas in mean placental thickness, area, volume, placenta to amniotic fluid SI ratio, and size of FVs (49.0 mm vs. 36.9 mm, 1.62 × 104 mm2 vs. 2.67 × 104 mm2, 5.13 × 105 mm3 vs. 6.56 × 105 mm3, 0.549 vs. 0.685, and 3.4 mm vs. 4.3 mm, respectively). The sensitivity and accuracy using globular appearance plus decreased FVs were greater than those using decreased FVs (P < 0.01). There was no significant difference among AUCs using globular appearance and decreased FVs, and globular appearance plus decreased FVs.Conclusions:Placental insufficiency was associated with placental thickness, area, volume, placenta to amniotic fluid SI ratio, and size of FVs. Evaluating FVs on T2-weighted RARE images can be useful for detecting placental insufficiency, particularly in placentas without globular appearance on MR images.