Growing Renal Vein Aneurysm Treated by Endovascular Repair: A Case Report and Literature Review.

Renal vein aneurysm (RVA) is extremely rare and often asymptomatic, disclosed only incidentally on diagnostic imaging modalities such as computed tomography and ultrasonography. Management is often just watchful follow-up, but some patients require intervention. We present the case of a 74-year-old man complaining of lower back pain in whom a 53-mm RVA was identified. He underwent successful endovascular repair using Amplatzer vascular plugs. The aneurysm had completely resolved by 12 months. Endovascular treatment of a primary RVA does not seem to have been reported previously. This is a milestone case in the management of RVA.

Foreign-body granulomas and abscesses caused by dropped gallstones after cholecystectomy: Four cases diagnosed with multimodality imaging.

Four cases (age range, 60-78 years, male:female = 1:3) who had undergone cholecystectomy presented with fever (n = 1), right abdominal pain with fever (n = 1), appetite loss with fever (n = 1), and absence of symptoms (n = 1). Computed tomography (CT) showed an irregular-shaped invasive mass or fluid collection in the right Morrison's pouch, right paracolic gutter, gallbladder fossa, subphrenic space, or abdominal wall. CT and ultrasound revealed gallstones in the granuloma in 3 cases and an abscess in one case. The inflammatory process induced by dropped gallstones may mimic peritoneal malignancies. Awareness of cholecystectomy and the detection of gallstones in the lesion are essential for the diagnosis of dropped gallstones.

Platypnea-orthodeoxia syndrome associated with aortic insufficiency and aortic elongation.

An 81-year-old female developed dyspnea only upon assuming a sitting position. Trans-esophageal echocardiography demonstrated left-to-right shunt flow across the atrial septum when the patient was sitting, and right-to-left shunt flow when she was supine, along with severe aortic insufficiency. She was diagnosed as having platypnea-orthodeoxia syndrome and her symptoms were completely resolved following aortic valve replacement, closure of a patent foramen ovale, and shortening of an elongated ascending aorta.

Invasion of histiocytic sarcoma into the spinal cord of HTLV-1 tax transgenic mice with HTLV-1-associated myelopathy/tropical spastic paraparesis-like disease.

Human T-cell leukemia virus type 1 (HTLV-1) can cause an aggressive malignancy known as adult T-cell leukemia/lymphoma (ATLL) as well as inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Transgenic (Tg) mice expressing HTLV-1 Tax also develop T-cell leukemia/lymphoma and an inflammatory arthropathy that resembles rheumatoid arthritis. We found that 8 of 297 Tax-Tg mice developed HAM/TSP-like disease with symmetrical paraparesis of the hind limbs, but these symptoms were absent in non-Tg littermates and in other mice strains at our animal facilities. We could perform detailed evaluations for five of these mice. These evaluations showed that the disease was not inflammatory, unlike that in HAM/TSP patients, but instead involved the invasion of histiocytic sarcoma cells into the lumbar spinal cord from the bone marrow where they had undergone extensive proliferation.

Natural infection of murine norovirus in conventional and specific pathogen-free laboratory mice.

Noroviruses cause most cases of acute viral gastroenteritis worldwide. The lack of a cell culture infection model for human norovirus necessitates the use of molecular methods and/or viral surrogate models amenable to cell culture to predict norovirus inactivation. Murine norovirus (MNV) may be used to construct a small animal model for studying the biology and pathogenesis of noroviruses because MNV is the only norovirus that replicates in cell culture and a small animal model. However, recent studies have shown that natural MNV infection is widespread in laboratory mouse colonies. We investigated MNV infection in both conventional and specific pathogen-free (SPF) genetically modified mice from Japan and the US, and commercial mice from several animal breeders in Japan, using serological and molecular techniques. MNV antibodies were detected in 67.3% of conventional mice and 39.1% of SPF mice from Japan and 62.5% of conventional mice from the US. MNV antibodies were also found in 20% of commercial SPF C57BL/6 mice from one of three breeders. Partial gene amplification of fecal isolates from infected animals showed that the isolates were homologous to reported MNV sequences. These results suggest that both conventional and SPF laboratory mice, including commercial mice, are widely infected with MNV, which might require considerable attention as an animal model of human disease.

Assessment of small bowel motility function with cine-MRI using balanced steady-state free precession sequence.

PURPOSE: To evaluate the use of cine-magnetic resonance imaging (MRI) with a steady-state free precession sequence to monitor and assess small bowel motility. MATERIALS AND METHODS: Sequential MRI, using a balanced steady-state free precession sequence, was performed in eight healthy male volunteers at 0, 15, 30, 45, and 60 minutes after oral administration of 1500 mL of nonabsorbable fluid to monitor small bowel contractions. Using the cine-mode display, small bowel contractions were reviewed and the luminal diameter was measured on each image to obtain frequency and amplitude of bowel contractions. RESULTS: The oral preparation was well tolerated without major complications. Cine-MRI provided high temporal, spatial, and contrast resolution for monitoring bowel contractions. Mean values with standard deviations of frequency and amplitude of bowel contractions were 6.0 ± 2.98/min and 10.4 ± 4.53 mm, respectively, and were 5.1 ± 3.38/min and 9.59 ± 5.57 mm at the jejunal loops and 6.9 ± 2.22/min and 11.2 ± 3.06 mm at the ileal loops. With the passage of luminal fluid, frequency of bowel contractions decreased and the bowels tended to pause their contractions. CONCLUSION: Cine-MRI provides sufficient dynamic images to observe small bowel contractions. Measurement of bowel caliber permits calculation of amplitude and frequency of the contractions for characterization and quantitative assessment of small bowel motility function.

Evaluation of computer-aided detection of lesions in mammograms obtained with a digital phase-contrast mammography system.

A computer-aided detection (CAD) system was evaluated for its ability to detect microcalcifications and masses on images obtained with a digital phase-contrast mammography (PCM) system, a system characterised by the sharp images provided by phase contrast and by the high resolution of 25-µm-pixel mammograms. Fifty abnormal and 50 normal mammograms were collected from about 3,500 mammograms and printed on film for reading on a light box. Seven qualified radiologists participated in an observer study based on receiver operating characteristic (ROC) analysis. The average of the areas under ROC curve (AUC) values for the ROC analysis with and without CAD were 0.927 and 0.897 respectively (P = 0.015). The AUC values improved from 0.840 to 0.888 for microcalcifications (P = 0.034) and from 0.947 to 0.962 for masses (P = 0.025) respectively. The application of CAD to the PCM system is a promising approach for the detection of breast cancer in its early stages.

CT diagnosis of acute mesenteric ischemia from various causes.

OBJECTIVE: Acute mesenteric ischemia can be caused by various conditions such as arterial occlusion, venous occlusion, strangulating obstruction, and hypoperfusion associated with nonocclusive vascular disease, and the CT findings vary widely depending on the cause and underlying pathophysiology. The aim of this article is to review the CT appearances of acute mesenteric ischemia in various conditions. CONCLUSION: Recognition of characteristic CT appearances and the variations associated with each cause may help in the accurate interpretation of CT in the diagnosis of mesenteric ischemia.