Background-CT Colonography (CTC) is a non-invasive option for colorectal cancer (CRC) screening. The accuracy of CTC as a screening tool among asymptomatic adults has not been well defined.

OBJECTIVE-Current generation MDCT technology facilitates identification of small, nonenhancing lesions in the pancreas. The objective of this study was to determine the prevalence of findings of unsuspected pancreatic cysts on 16-MDCT in a population of adult out-patients imaged for disease unrelated to the pancreas. MATERIALS AND METHODS-Contrast-enhancedMDCT scans of the abdomen were reviewed from 2,832 consecutive examinations to identify pancreatic cysts. Patients with a history of pancreatic lesions or predisposing factors for pancreatic disease or who were referred for pancreatic CT were excluded.RESULTS-A total of 73 patients had pancreatic cysts, representing a prevalence of 2.6 per 100 patients (95% CI, 2.0-3.2). Cysts ranged in size from 2 to 38 mm (mean, 8.9 mm) and were solitary in 85% of cases. Analysis of demographic information showed a strong correlation between pancreatic cysts and age, with no cysts identified among patients under 40 years and a prevalence of 8.7 per 100 (95% CI, 4.6-12.9) in individuals from 80 to 89 years. After controlling for age, cysts were more common in individuals of the Asian race than all other race categories, with an odds ratio of 3.57 (95% CI, 1.05-12.13). There was no difference by sex in the prevalence of cysts (p = 0.527); however, cysts were on average 3.6 mm larger (p = 0.014) in men than women.CONCLUSION-In this outpatient population, the prevalence of unsuspected pancreatic cysts identified on 16-MDCT was 2.6%. Cyst presence strongly correlated with increasing age and the Asian race. KeywordsCT; incidence; MDCT; pancreatic cyst; prevalence This year an estimated 37,170 Americans will be diagnosed with pancreaticcancer, and 33,370 will die from the disease [1]. Detection of this disease in its early curable stages is difficult, to the extent that more than 80% of pancreatic cancers have metastasized or are locally unresectable at the time of diagnosis [2]. As a result, the 5-year survival rate for all stages combined is 5% [3]. The detection and treatment of early precursors to invasive pancreatic cancer offer the best hope for improving outcome.Address correspondence to K. M. Horton (E-mail: kmhorton@jhmi.edu). Three histologically distinct precursors to invasive adenocarcinoma of the pancreas have been identified. These include the intraductal papillary mucinous neoplasm, the mucinous cystic neoplasm, and pancreatic intraepithelial neoplasia [4]. Pancreatic intraepithelial neoplasias are too small to be detected by most imaging methods. However, both intraductal papillary mucinous neoplasms and mucinous cystic neoplasms should be detectable, and both appear as cystic pancreatic lesions on cross-sectional imaging [5]. This suggests that an asymptomatic cyst detected in the pancreas could represent a treatable precursor to invasive cancer. NIH Public AccessA limited number of previous studies have reported both the incidence and prevalence of pancreatic cysts across a range of patient populations using autopsy, MRI, and CT [6][7][8][9]. However, curre...

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The median arcuate ligament is a fibrous arch that unites the diaphragmatic crura on either side of the aortic hiatus. The ligament usually passes superior to the origin of the celiac axis. However, in some people, the ligament inserts low and thus crosses the proximal portion of the celiac axis, causing compression and sometimes resulting in abdominal pain. The diagnosis of clinically significant celiac axis compression, referred to as median arcuate ligament syndrome, is traditionally made with conventional angiography; however, the condition can now be diagnosed with three-dimensional computed tomographic (CT) angiography. In patients with median arcuate ligament syndrome, CT angiograms demonstrate a characteristic focal narrowing in the proximal celiac axis. The focal narrowing has a characteristic hooked appearance, which can help distinguish this condition from other causes of celiac artery narrowing, such as atherosclerotic disease. Once the disorder has been diagnosed, surgery can be performed to relieve the compression. In some patients, the ligamentous constriction of the celiac axis causes vascular damage, which may require vascular reconstruction. CT angiography can play a role in the diagnosis of median arcuate ligament syndrome by demonstrating the characteristic focal narrowing of the celiac artery in patients presenting with the appropriate clinical symptoms.

Sclerosing mesenteritis is a complex inflammatory disorder of the mesentery. Although sclerosing mesenteritis is often associated with other idiopathic inflammatory disorders such as retroperitoneal fibrosis, sclerosing cholangitis, Riedel thyroiditis, and orbital pseudotumor, its exact cause is unknown. The computed tomographic (CT) appearance of sclerosing mesenteritis will vary depending on the predominant tissue component (fat, inflammation, or fibrosis). CT plays an important role in suggesting the diagnosis in the proper clinical setting and can be useful in distinguishing sclerosing mesenteritis from other mesenteric diseases with similar CT features such as carcinomatosis, carcinoid tumor, lymphoma, desmoid tumor, and mesenteric edema. Nevertheless, surgical biopsy and pathologic analysis are usually necessary to make the diagnosis. Treatment may consist of therapy with steroids, colchicine, immunosuppressive agents, or orally administered progesterone. Surgical resection is sometimes attempted for definitive therapy, although the surgical approach is often limited by vascular involvement. CT with three-dimensional volume rendering is optimal for accurate, noninvasive follow-up of sclerosing mesenteritis and of any potential complications.