Abdominal Imaging

The purpose of this two-part article is to review the cross-sectional anatomy of the ampulla and periampullary region, to propose novel and optimized MDCT and MRI techniques that allow accurate evaluation of the ampulla of Vater, and to summarize the cross-sectional imaging features of benign and malignant ampullary conditions. In this first part, we will review the normal anatomy of the ampullary region, provide suggestions on how to optimize evaluation of the ampullary region by MDCT and MRI, and review the imaging features of select epithelial neoplasms of the ampulla...

Endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered upper gastrointestinal anatomy, such as Roux-en-Y gastric bypass (RYGB), can be more challenging compared to those with a normal anatomy. Detailed assessment of cross-sectional imaging features by the radiologist, especially the pancreaticobiliary anatomy, strictures, and stones, is very helpful to the endoscopist in planning the procedure. In addition, any information on enteral anastomoses (for e.g., gastrojejunal strictures and afferent limb obstruction) is also very useful...

PURPOSE: There are distinct quantifiable features characterizing renal cell carcinomas on contrast-enhanced CT examinations, such as peak tumor enhancement, tumor heterogeneity, and percent contrast washout. While qualitative visual impressions often suffice for diagnosis, quantitative metrics if developed and validated can add to the information available from standard of care diagnostic imaging. The purpose of this study is to assess the use of quantitative enhancement metrics in predicting the Fuhrman grade of clear cell RCC...

PURPOSE: The objective of this study is to assess the performance of qualitative and quantitative imaging features for the differentiation of deep venous thrombosis (DVT) from mixing artifact on routine portal venous phase abdominopelvic CT. METHODS: This retrospective study included 40 adult patients with a femoral vein filling defect on portal venous phase CT and a Duplex ultrasound (n = 36) or catheter venogram (n = 4) to confirm presence or absence of DVT. Two radiologists (R1, R2) assessed the femoral veins for various qualitative and quantitative features...

PURPOSE: To develop predictive models for lymph node (LN) metastasis in testicular germ cell tumors. MATERIALS AND METHODS: 291 patients with testicular germ cell tumors were included, which were divided into seminomatous and nonseminomatous groups. For screening the risk factors for LN metastasis, the tumor-related characteristics (including histopathological information and tumor markers) alpha fetoprotein and the lymph node-related features on CT were compared between metastatic cases and nonmetastatic cases...

PURPOSE: We examined different approaches aimed to deal with the signal fluctuation of pancreatic T2* values due to fat infiltration in order to obtain accurate estimates of iron overload. METHODS: Pancreatic T2* values were assessed in 20 patients (13 females, 37.24 ± 9.12 years) enrolled in the Myocardial Iron Overload in Thalassemia network without and with the application of fat suppression-FS (T2*-NoFS and T2*-FS). T2* values were assessed in three different ways: (1) from the immediate fit (original T2*); (2) discarding the echoes until the achievement of a good visual concordance between the signal and the model (final_vis T2*); (3) eliminating the echoes until the achievement of a fitting error (known) <5% (final_thres T2*)...

PURPOSE: To discuss the diverse imaging features of pancreatic and extra-pancreatic lesions of IgG4-related disease (IgG4-RD) on multi-detector CT (MDCT). METHODS: This retrospective study was approved by our institutional research ethics board, and informed consent was waived. From 2008 to 2013, 159 patients including 120 men (mean age 57 years; range 27-79 years) and 39 women (mean age 51 years; range 25-83 years) who met the comprehensive diagnostic criteria for IgG4-RD (2011) were enrolled...

Laparoscopic radial nephrectomy (LRN) and microwave ablation (MWA) are optional treatment for renal cell carcinoma (RCC). However, the comparative study with two techniques remains lacking. The aim of this study was to evaluate midterm results of MWA vs. LRN in patients with small RCC. A total of 426 patients with ≤ 4 cm RCC were included from April 2006 to October 2012. Ninety-eight patients underwent MWA and 328 patients LRN. The survival, recurrence, and renal function changes were compared between two treatments...

PURPOSE: To explore the role of histogram analysis of apparent diffusion coefficient (ADC) MRI maps based on entire tumor volume data in determining pancreatic neuroendocrine tumor (PNT) grade. METHODS AND MATERIALS: Retrospective evaluation of 22 patients with PNTs included low-grade (G1; n = 15), intermediate-grade (G2; n = 4), and high-grade (G3; n = 3) tumors. Regions of interest containing the lesion were drawn on every section of the ADC map containing the tumor and summated to obtain histograms for entire tumor volume...

Gastro-duodenal obstruction encompasses a spectrum of benign and malignant disease. Historically, chronic peptic ulcer disease was the main cause of gastro-duodenal obstruction, whereas now malignant cause with gastric carcinomas for gastric obstruction and pancreatic tumors for duodenal obstruction predominate. This paper reviews the role of CT in diagnosing gastro-duodenal obstruction, its level, its cause by identifying intraluminal, parietal, or extrinsic process, and the presence of complication.

PURPOSE: To retrospectively evaluate CT sensitivity for characterizing adrenal adenoma according to lesion size. MATERIALS AND METHODS: Between January 2004 and November 2012, 140 patients with 140 histologically proven adenomas underwent preoperative adrenal CT protocols consisting of unenhanced CT, early enhanced CT, and delayed enhanced CT. Adenomas were divided into three size groups: small adenoma (n = 60), ≥ 1 to <2 cm; medium adenoma (n = 47), ≥ 2 to <3 cm; and large adenoma (n = 33), ≥ 3 cm...

Amyloidosis is extremely rare, with an estimated 2225 new US cases reported annually. Signs and symptoms of the disease are subtle and imaging findings are not pathognomonic. Currently, diagnosis requires biopsy to demonstrate the deposition of amyloid. Elastography is a new imaging modality that evaluates tissue elasticity. It has shown to have efficacy in characterizing thyroid nodules, detecting prostate cancer, and staging liver fibrosis. We present a case of hepatic amyloidosis in a 51-year-old male that demonstrates significantly increased stiffness with a median value of 99...

PURPOSE: (18)F-FDG PET/CT is used to characterize many malignancies, but is not recommended for localized prostate cancer. This study explores the value of multi-parametric MRI (mpMRI) in characterizing incidental prostate (18)F-FDG uptake. METHODS: Thirty-one patients who underwent (18)F-FDG PET/CT for reasons unrelated to prostate cancer and prostate mpMRI were eligible for this retrospective study. The mpMRI included T2-weighted (T2W), dynamic contrast enhancement (DCE), apparent diffusion coefficient (ADC), and MR spectroscopy (MRS) sequences...

OBJECTIVE: Rectal cancers are the second most common GI carcinoma. Prognosis and therapeutic decisions hinge on the extent of disease. We present a comprehensive structured approach for staging rectal cancer using MRI to ensure the clear, concise, and standardized communication of disease extent to guide optimal treatment planning. CONCLUSION: MRI is crucial for local staging of rectal cancer. A standardized approach to reporting of rectal MRI focused on communication of essential treatment planning and prognostic indicators ensures maximal added value to referring physicians to guide appropriate management...

Hemangiomas are common lesions, best known for their appearance in the liver. Their appearance in less common locations, such as the gastrointestinal and genitourinary tracts, is less well known. We will review the typical and atypical appearance of hemangiomas in these locations on sonography, CT, and MRI.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

PURPOSE: The purpose of this study is to determine the prevalence of left renal vein compression in patients with varicoceles. METHODS: Abdominal and pelvis contrast-enhanced CT images from 100 male patients with varicoceles (mean age 50.6 years) and 100 matched control patients (mean age 49.8 years) were retrospectively reviewed. The diameter of the left renal vein was measured as it crosses between the aorta and superior mesenteric artery and was classified as compressed if there was greater than 50% narrowing...

PURPOSE: To investigate the incidence of high T2 signal rims surrounding leiomyomas, evaluate if a particular T2-weighted sequence is more effective in depicting this rim, and determine if this sign is useful in differentiating pedunculated leiomyomas from other solid adnexal masses. MATERIALS AND METHODS: In this retrospective study, two radiologists evaluated 233 T2 dark pelvic masses (223 uterine leiomyomas and 10 ovarian fibromas) in 60 women (mean age 47) on Magnetic resonance imaging for the presence of a high signal rim...