Known or newly found CA and CHA variations could be systematically described in detail. The authors propose a hypothetical anatomic model for summarizing the observed CHA variations.

Although celiac axis stenosis is a frequently encountered occlusive vascular disease, clinically significant ischemic bowel disease caused by celiac axis stenosis is rarely reported due to rich collateral circulation from the superior mesenteric artery (SMA). The most important and frequently encountered collateral vessels from the SMA in patients with celiac axis stenosis are the pancreaticoduodenal arcades and the dorsal pancreatic artery. Subtypes of collateral pathways via the dorsal pancreatic artery include a longitudinal pathway between the celiac branches and the SMA or its branches and a transverse pathway to either the splenic or gastroduodenal artery. A communicating channel between the right hepatic artery and the SMA can be a route for collateral circulation. Hepatic artery variants cause the development of unique collateral pathways that have different characteristics depending on the type of variant. These collateral pathways include intrahepatic interlobar collateral vessels, right gastric to left gastric arterial anastomoses, left hepatic to left gastric arterial anastomoses, and peribiliary arterial plexuses. Major collateral pathways in patients with celiac axis stenosis can be identified with spiral CT, and knowledge concerning this collateral circulation may be important for certain medical procedures such as interventional procedures for the management of hepatic tumors, pancreaticobiliary surgery, and liver transplantation.

The findings in this initial experience suggest that stent-graft insertion may be a safe and effective alternative to surgical treatment of aortic and arterial aneurysms in patients with Behçet disease.

Epidermal inclusion cysts most often appeared sonographically as a hypoechoic mass containing variable echogenic foci without color Doppler signals. Ruptured epidermal cysts, however, may have lobulated contours and show color Doppler signals, mimicking a solid mass.

Purpose. We evaluated the sonographic findings in epidermal inclusion cysts and related them to the pathologic findings.Methods. We retrospectively reviewed the sonograms and pathology specimens of 24 patients with pathologically proven epidermal inclusion cysts. We evaluated the lesions for shape, size, internal echogenicity, posterior sound enhancement, and presence of color Doppler signals. We classified the masses into 5 sonographic types according to their internal echogenicity. The relationship between the sonographic types and the pathologic findings was examined.Results. The masses were ovoid or spherical in 17 cases (71%), lobulated in 5 (21%), and tubular in 2 (8%). The longest diameter ranged from 1 to 6 cm (mean, 3.1 cm). Twenty-three cases (96%) were associated with posterior sound enhancement. Color Doppler signals were absent in 20 cases, but some vascularity was noted in 4 ruptured epidermal cysts, in areas of granulation tissue. The most common sonographic type was a hypoechoic lesion with scattered echogenic reflectors (10 cases). Sonographic findings were related to the lamellation of keratin debris and the granulation tissue secondary to rupture.Most cases with a lobulated configuration (4 of 5) or color Doppler signals (4 of 4) were ruptured cysts.Conclusions. Epidermal inclusion cysts most often appeared sonographically as a hypoechoic mass containing variable echogenic foci without color Doppler signals. Ruptured epidermal cysts, however, may have lobulated contours and show color Doppler signals, mimicking a solid mass.

Peripheral primitive neuroectodermal tumors (PNETs) arising in the retroperitoneum tend to be large and aggressive. Although the imaging appearance of peripheral PNETs is nonspecific, these tumors should be considered in the differential diagnosis when one encounters a large retroperitoneal mass with aggressive features.

PurposeTo investigate the clinical benefits of F18-fluorodeoxyglucose-positron emission tomography and computed tomography (18F-FDG-PET/CT) over multi-detector row CT (MDCT) in preoperative staging of gastric cancer.MethodsFDG-PET/CT and MDCT were performed on 78 patients with gastric cancer pathologically diagnosed by endoscopy. The accuracy of radiologic staging retrospectively was compared to pathologic result after curative resection.ResultsPrimary tumors were detected in 51 (65.4%) patients with 18F-FDG-PET/CT, and 47 (60.3%) patients with MDCT. Regarding detection of lymph node metastasis, the sensitivity of FDG-PET/CT was 51.5% with an accuracy of 71.8%, whereas those of MDCT were 69.7% and 69.2%, respectively. The sensitivity of 18F-FDG-PET/CT for a primary tumor with signet ring cell carcinoma was lower than that of 18F-FDG-PET/CT for a primary tumor with non-signet ring cell carcinoma (35.3% vs. 73.8%, P < 0.01).ConclusionDue to its low sensitivity, 18F-FDG-PET/CT alone shows no definite clinical benefit for prediction of lymph node metastasis in preoperative staging of gastric cancer.

MRI-PDFF is an accurate non-invasive method for quantifying hepatic fat for various hepatic disorders, and may be preferable for measuring fat fraction in the right liver for more precise values in longitudinal monitoring, while avoiding FF measurement in the left liver. Advances in knowledge: MRI-PDFF provides a non-invasive and accurate quantification of hepatic steatosis in various hepatic disorders. It would be preferable to measure FF in the right liver than in the left liver.