Noritaka Seino

Diagnostic accuracy of ultra-high-b-value 3.0-T diffusion-weighted MR imaging for detection of prostate cancer

PURPOSE To investigate the diagnostic accuracy of 3.0-T diffusion-weighted imaging (DWI) for detection of prostate cancer by using different b-values. METHODS Seventy-three patients underwent magnetic resonance imaging (MRI) at 3.0 T. Three MRI sets were reviewed by two radiologists: MRI and DWI (b = 500 s/mm(2)) (protocol A), MRI and DWI (b = 1000 s/mm(2)) (protocol B), and MRI and DWI (b = 2000s/mm(2)) (protocol C). Areas under the receiver operating characteristic curve (AUCs) were calculated. RESULTS The mean of the AUCs in protocol C was larger than those in protocol A and in protocol B (P<.05). CONCLUSION DWI (b = 2000s/mm(2)) at 3.0 T can improve the diagnostic accuracy for detection of prostate cancer.

MRI of the neck at 3 Tesla using the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) (BLADE) sequence compared with T2-weighted fast spin-echo sequence.

To evaluate motion artifacts, tissue contrasts, and lesion detectability in the neck with the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) (BLADE) technique.

MR Imaging of Fetuses to Evaluate Placental Insufficiency

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.

Ultrasonography-guided percutaneous transhepatic portacaval shunt creation

We successfully created a percutaneous transhepatic portacaval shunt under ultrasonography (US) guidance in a 46-year-old man with refractory ascites. The shunt was created to salvage an attempt to create a transjugular intrahepatic portosystemic shunt (TIPS) that failed because of the elevated level of portal vein bifurcation due to alcoholic liver cirrhosis. Under US guidance, we simultaneously punctured the right branch of the portal vein and the inferior vena cava (IVC) using a two-step biliary drainage set. An Amplatz gooseneck snare was introduced transjugularly to retrieve the percutaneously inserted guidewire. The intrahepatic tract between the portal vein and the IVC was dilated using a balloon catheter, and a stent was placed in the tract. The patient showed complete resolution of ascites at discharge. We assume that our method is an alternative method for TIPS creation in patients with inadequate anatomical relations between the portal vein branches and the hepatic veins. This approach is thought to be feasible for patients with occluded or small hepatic veins.

Multidetector computed tomography in an adult patient with silent patent ductus arteriosus.

Yasushi Akutsu,MD, PhD, FACP,∗ TakehikoGokan,MD, PhD,† Noritaka Seino,MD, PhD,† Kyouichi Kaneko,MD,∗ Yusuke Kodama, MD, PhD,∗ Youichi Kobayashi, MD, PhD∗ ∗Division of Cardiology, Department of Medicine, Showa University School of Medicine, Shinagawaku, Tokyo, Japan; †Department of Radiology, Showa University School of Medicine, Shinagawaku, Tokyo, Japan Address for correspondence: Yasushi Akutsu, MD, PhD Division of Cardiology Department of Medicine Showa University School of Medicine 1-5-8 Hatanodai, Shinagawaku Tokyo 142–8666, Japan hzn01233@s02.itscom.net