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.

Sclerosing mesenteritis, a rare mesenteric disorder, in a patient with ulcerative colitis.

A 60-year-old female who had been ill with ulcerative colitis for more than ten years presented with upper abdominal pain. A flare-up of ulcerative colitis was unlikely, because she did not report rectal bleeding, altered bowel habit, and changes of stool form. A poorly defined mass with mild tenderness was palpable in the upper abdomen, with increased levels of serum pancreatic enzymes, leading us to suspect pancreatic disease. Although CT scan revealed no abnormalities in the pancreas, a well-defined, heterogeneous soft tissue mass was found in the small bowel mesentery. Although several different diagnoses were considered, characteristic features on CT strongly supported diagnosis of sclerosing mesenteritis. The symptoms resolved quickly without specific treatment. The mesenteric lesion has never changed and no unfavorable events have yet occurred.

Atlas of breast magnetic resonance imaging.

Magnetic resonance imaging (MRI) of the breast has become important not only for assessing the extent of breast cancer for breast-conserving surgery but also for the evaluation and diagnosis of other benign and malignant pathologies. We radiologists therefore need to know the appropriate indications for performing breast MRI and understand the MRI features of breast disease. We herein review and discuss the application of current pulse sequences and the imaging strategies for MRI of breast pathologies. We will illustrate the MRI features of various breast pathologies including malignant tumors such as invasive and noninvasive ductal carcinoma, special types of invasive carcinoma (mucinous, apocrine, lobular carcinoma, spindle cell carcinoma, and so on), inflammatory carcinoma, semimalignant tumor (phyllodes tumor), benign tumors (fibroadenoma, intraductal and intracystic papilloma), inflammatory conditions, and postsurgical changes. We will also demonstrate three-dimensional fusion images of MR ductography and breast MRI of patients with nipple discharge.

A novel mutagen, 2-(5-hydroxy-4,6-dinitroindolyl) ethanol, formed in the reaction between 5-hydroxytryptamine and nitrite under acid conditions, especially in the presence of L-cysteine.

We examined the mutagenic activity of each of 29 amino acids mixed under acidic conditions with 5-hydroxytryptamine (5-HT) and nitrite using Salmonella typhimurium strain TA 100 with or without a metabolic activation system (S9 mix). The reaction mixture containing L-cysteine was strongly mutagenic without S9 mix. We subjected an ethyl acetate extract of the reaction mixture to HPLC, isolated a mutagenic component, and investigated its chemical structure by LC-mass spectrometry (MS), high-resolution fast atom bombardment (HRFAB)-MS, and 1H and 13C NMR. We identified the mutagen as 2-(5-hydroxy-4,6-dinitro-3-indolyl) ethanol (2HDIE). We injected 8 mg/kg 2HDIE i.p. into male ICR mice and found that the compound increased the frequency of micronuclei in peripheral reticulocytes. Our results suggest that 2HDIE might be formed in vivo by consumption of 5-HT, nitrite and L-cysteine in foods, and might act as a mutagen.

CT of internal hernias.

Computed tomography (CT) plays an important role in diagnosis of acute intestinal obstruction and planning of surgical treatment. Although internal hernias are uncommon, they may be included in the differential diagnosis in cases of intestinal obstruction, especially in the absence of a history of abdominal surgery or trauma. CT findings of internal hernias include evidence of small bowel obstruction (SBO); the most common manifestation of internal hernias is strangulating SBO, which occurs after closed-loop obstruction. Therefore, in patients suspected to have internal hernias, early surgical intervention may be indicated to reduce the high morbidity and mortality rates. In a study of 13 cases of internal hernias, nine different types of internal hernias were found and the surgical and radiologic findings were correlated. The following factors may be helpful in preoperative diagnosis of internal hernias with CT: (a) knowledge of the normal anatomy of the peritoneal cavity and the characteristic anatomic location of each type of internal hernia; (b) observation of a saclike mass or cluster of dilated small bowel loops at an abnormal anatomic location in the presence of SBO; and (c) observation of an engorged, stretched, and displaced mesenteric vascular pedicle and of converging vessels at the hernial orifice.