Jei Hee Lee

Eosinophilic hepatic necrosis: magnetic resonance imaging and computed tomography comparison.

Objective: To compare the findings of magnetic resonance (MR) imaging with those of computed tomography (CT) of focal liver lesions related to peripheral eosinophilia. Methods: For 12 patients with peripheral eosinophilia (>7%) examined with hepatic MR imaging and CT, 52 focal hepatic lesions larger than 0.5 cm, including 31 lesions simultaneously found on the 2 imaging modalities, were subjected to a comparative analysis of their imaging features. Results: The total number of lesions distinguished from background liver was 39 (75%) on MR imaging and 44 (85%) on CT scans. On arterial phase images of 10 patients with comparable data, homogeneously hyperintense lesions were demonstrated more frequently (P = 0.006) on MR imaging (16 [50%] of 32 lesions) than on CT scans (4 [13%] of 32 lesions). Only 7 (22%) of the 32 hypoattenuating lesions on portal phase CT were depicted as hypointense lesions on portal phase MR images in 12 patients. On delayed phase images in 8 patients, the number of hyperintense lesions on MR images (9 [56%] of 16) was greater (P = 0.077) than that seen on the CT scans (4 [25%] of 16). Conclusions: For many focal hepatic lesions related to peripheral eosinophilia, dynamic MR imaging more easily demonstrates lesional enhancement on arterial and delayed phases than CT scans. Because of the higher degree of lesional enhancement of MR imaging compared with CT, the lesion-to-liver contrast may not be sufficient to distinguish the lesion from the background liver, resulting in decreased sensitivity of portal phase dynamic MR imaging.

Advanced gastric carcinoma with signet ring cell carcinoma versus non-signet ring cell carcinoma: differentiation with multidetector CT.

Objective: The purpose of this study is to assess the capability of multidetector computed tomography (MDCT) to assist in the differentiation of advanced gastric carcinoma with signet ring cell type from that with non-signet ring cell carcinoma (NSRC) with a focus on the thickened stomach wall itself. Methods: We retrospectively reviewed MDCT results in 80 patients with pathologically proven advanced gastric carcinoma with signet ring cell carcinoma (SRC) (n = 35) and NSRC (n = 45). MDCT images of 80 patients were analyzed retrospectively on gross appearance of thickened gastric wall (polypoid/fungating/ulcerative/diffuse infiltrative), predominantly thickened layer (inner/outer), contrast-enhancement pattern (nonlayered/layered) and degree of enhancement (high/moderate/low). Results: The most common type of gross appearance in both carcinomas was fungating, and the more common contrast-enhancement pattern in both carcinomas was a nonlayered pattern. The predominantly thickened layer was a high attenuation inner layer in both carcinomas. High-degree contrast enhancement was more common in SRC (37.1% of patients) than NSRC (15.6% of patients) with statistically significant difference (P = 0.01). Conclusions: Multidetector CT cannot distinguish SRC from NSRC based on the thickened stomach wall alone. But, high-degree contrast enhancement was more common in advanced gastric carcinoma with SRC than that with NSRC.

MR Cholangiography of Accessory Bile Duct Connected to the Stomach

WEB This is a Web exclusive article. ccessory bile ducts, often draining a segment of the right lobe of the liver into the common bile duct or the gallbladder, have been found at as many as 4% of necropsies [1]. Accessory bile ducts connected to the gastrointestinal tract are extremely rare [1, 2]. Since the first report of double bile duct draining into the gastrointestinal tract as a congenital anomaly registered by Vesalius in 1543, more than 50 cases of double biliary drainage have been reported worldwide [2]. We describe a case of accessory bile duct that connected the caudate lobe of the liver to the stomach in which MR cholangiography (MRC) showed the biliary anomaly and provided sufficient evidence for development of an appropriate surgical plan. Subsequent intraoperative cholangiography supplemented the imaging diagnosis, and surgical resection was performed. To our knowledge, there have been no reported cases of MRC diagnosis of accessory bile duct connected to the gastrointestinal tract.

Pneumoperitoneum caused by transhepatic air leak after metallic biliary stent placement

A self-expanding metallic biliary stent was placed for palliation of a common bile duct obstruction in a 68-year-old male with unresectable pancreatic head cancer 3 days after initial percutaneous right transhepatic catheter decompression. The stent crossed the ampulla of Vater. Three days later, the stent was balloon-dilated and the percutaneous access was removed. At removal, a small contrast leak from the transhepatic tract was seen. Three days later, pneumoperitoneum was found with symptoms of peritoneal irritation and fever. A widely open sphincter of Oddi caused by the metallic stent, accompanied by delayed sealing of the transhepatic tract, may have caused the air and bile leakage into the peritoneal space. This case shows that pneumoperitoneum may occur without ductal tear or bowel injury, with a biliary stent crossing the ampulla of Vater.

Accuracy of Preoperative Local Staging of Primary Colorectal Cancer by Using Computed Tomography: Reappraisal Based on Data Collected at a Highly Organized Cancer Center

Purpose In patients with colorectal cancer, preoperative staging using various imaging technologies is important for establishing the treatment plan and predicting the prognosis. Although computed tomography (CT) has been used most widely, the versatility of CT accuracy was primarily because of the lack of specialization. In this study, we aimed to identify whether any advancement in abdominal CT accuracy in the prediction of local staging has occurred. Methods Between December 2014 and November 2015, patients with colorectal cancer were retrospectively enrolled. All CT findings were retrospectively reported. A total of 285 patients were included, and their retrospectively collected data were retrospectively reviewed, focusing on a comparison between preoperative and postoperative staging. Results The overall prediction accuracy of the T stage was 55.1%, with overstaging occurring in 63 (22.1%) and understaging in 65 patients (22.8%). The sensitivity and specificity were 90.0% and 68.4%, respectively. The overall prediction accuracy of the N stage was 54.7%, with overstaging occurring in 89 (31.2%) and understaging in 40 patients (14.1%). The sensitivity and specificity were 71.9% and 63.2%, respectively. The CT accuracies by pathologic stage were 0%, 62.2%, 25.3%, and 81.2% for stages 0 (Tis N0), I, II, and III, respectively. Conclusion CT has good sensitivity for detecting colon cancers with tumor invasion beyond the bowel wall. However, detection of nodal involvement using CT is unreliable. In our opinion, abdominal CT alone has limitations in predicting the local staging of colorectal cancer, and additional technologies, such as CT plus positron emission tomography and/or colonography, will improve its accuracy.

Three cases of pancreatic pseudocysts associated with dorsal pancreatic agenesis

Agenesis of the dorsal pancreas (ADP) is an extremely rare congenital anomaly. Human pancreas is formed by ventral and dorsal endodermal buds of the foregut endoderm. The dorsal bud forms the upper part of the head, neck, body, and tail of the pancreas and the ventral bud generates most of the head and uncinate process. ADP is derived from the embryologic failure of the dorsal pancreatic bud to form the pancreatic body and tail. ADP can be related to some diseases and conditions such as pancreatitis, hypoglycemia, and rarely pancreatic tumors. The association between cystic lesions with ADP has previously been reported. Three cases of cystic lesions of the pancreas with ADP were diagnosed clinically based on the imaging features and without any past history of pancreatitis. However, the pathologic diagnosis of resected lesions confirmed pseudocysts without pathologic evidence of tumor. We report 3 cases of pancreatic pseudocysts associated with ADP