Pancreatic pseudotumors: Computed tomography

Although pancreatic disease is suspected initially by historical or biochemical findings, the nature of the pathologic process in the past was frequently established only through invasive procedures. Inferences can be drawn from routine roentgenologic examinations, but visualization of the pancreas has only recently been achieved. Of the currently available noninvasive imaging procedures, computed tomography, in our opinion, is the screening procedure of choice. Care in the interpretation of pancreatic masses must be exercised since some of the findings can be attributed to anatomic variants, normal adjacent structures, or other neighboring pathologic processes.     

Computed tomographic diagnosis of radiation ileitis

Two patients were studied by CT after resection of colon carcinoma followed by abdominal radiation therapy. Based upon the findings of a localized, mass-like confluence of shortened loops of bowel with thickening of bowel wall, adherence of adjoining loops, thickening of the adjacent mesentery, and increased density of mesenteric fat the patients were considered to have radiation ileitis. Recurrent tumor was excluded by autopsy and confirmed by a 1-year asymptomatic follow-up period.     

Solid and papillary epithelial pancreatic neoplasm: An unusual tumor

Solid and papillary epithelial neoplasms of the pancreas are uncommon. These grow to a large size, are often palpable, and occur most often in young black women. The tumors have a characteristic histologic appearance and a low malignant potential. Heavy tumor calcification is an unusual finding. Two cases with radiologie-pathologic correlation are presented herein.     

Gastric intramural pseudocyst: Computed tomographic diagnosis

The authors describe a case of pancreatic pseudocyst presenting as an intramural gastric mass on upper gastrointestinal examination (UGI) and computed tomography (CT) of the abdomen. The correct diagnosis of this rare entity was suggested preoperatively on the basis of the radiographic findings presented herein.     

Carcinoid tumors of the pancreas: CT findings

Computed tomographic (CT) and ultrasound (US) findings in four cases of carcinoid tumors of the pancreas are reported. Differential diagnosis with other endocrine and nonendocrine pancreatic tumors is discussed. CT and US techniques play an important role in diagnosis, prognosis, and treatment of these tumors.     

Ultrasound and computed tomographic demonstration of portal vein thrombosis in hepatocellular carcinoma

Two cases of multinodular hepatocellular carcinoma (HCC) in which ultrasound and computed tomography (CT) revealed portal vein thrombosis are presented. The diagnostic value of determining the presence of portal vein thrombosis in patients with suspected HCC is discussed.     

Complications of endoscopic retrograde sphincterotomy: Computed tomographic evaluation

Although the reported complication rate of endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy is low, patients often experience abdominal pain postprocedure. When pain persists, or fever and leukocytosis develop, a procedure-related complication should be suspected. The authors reviewed a series of 36 patients referred to computed tomography (CT) for evaluation of possible complications following ERCP with sphincterotomy. Initial CT scans were obtained within 24 h in 19 patients, and during the second to seventh day in the remainder. Complications detected by CT included acute pancreatitis (23), duodenal perforation (11), retroperitoneal dissection of air (4), pneumoperitoneum (4), and development of retroperitoneal abscess (4). Eight patients had normal CT scans except for air and contrast material in the biliary tree. The severity and extent of injury were readily assessed by CT, and response to therapy effectively monitored by serial CT examinations. Thirty-one cases (31 of 36) were successfully managed conservatively with antibiotics, intravenous hydration, and restriction of oral intake. Four patients required surgical intervention for drainage of a retroperitoneal abscess (3) or a pseudocyst (1). A fifth patient required intensive care resuscitation for septic shock. We conclude that CT is the study of choice for evaluating the patient with suspected complication following ERCP and sphincterotomy.     

常见肋骨肿瘤和肿瘤样病变的CT诊断

目的:讨论肋骨肿瘤和肿瘤样病变的CT表现以及各自的特点。材料与方法:取经手术和病理证实,或临床动态观察证实的肋骨病变50例。所有病例均行X线、CT检查。2例行MRI检查。结果:32例为良性病变,其中12例为骨岛,9例为骨纤维异常增殖症,7例为软骨类良性肿瘤,4例为骨感染性病变(2例为结核,2例为非特异性感染)。恶性病变18例,其中转移瘤10例,骨髓瘤4例,骨巨细胞瘤4例。结论:常见的肋骨肿瘤和肿瘤样病变一般都具有某些有助于我们诊断的特征性的CT表现。多数情况下,我们都能通过这些CT表现较好的区分常见的肋骨肿瘤和肿瘤样病变。     

Computed tomography of gastrointestinal leiomyosarcoma

Computed tomography (CT) was performed in 6 patients with gastrointestinal leiomyosarcoma. The characteristic CT findings were a large extraluminal mass, apparently mesenteric in location, with central areas of necrosis. These findings were present in 5 of the 6 patients. Enhancement of the rim of the tumor was seen in 2 of 3 patients who had scans before and after administration of intravenous contrast material. CT identified the site of origin of tumor in only 2 patients. The characteristic CT findings should suggest the diagnosis of gastrointestinal leiomyosarcoma.     

Improved survival with early CT diagnosis of pancreatic abscess

Until recently pancreatic abscess was often a lethal complication of acute pancreatitis. A major factor contributing to this high mortality has been delay in diagnosis. When combined with diagnostic needle aspiration, computed tomography (CT) has greatly enhanced the early detection of pancreatic abscesses. In the past 5 years at our institutions 23 patients with proven pancreatic abscesses were evaluated early in their clinical course by CT. In follow-up ranging from 4 months to 4 1/2 years there were only 4 deaths: a mortality rate of 17%. Many of the surviving patients had a long and protracted clinical course (mean length of hospitalization, 58 days) and reoperation for recurrent abscess or gastrointestinal complications was required in 9 patients (39%). Computed tomography proved helpful both in localizing the site of de novo or recurrent pancreatic abscess and in detecting postoperative complications. An aggressive approach to early CT scanning with diagnostic needle aspiration appears to be a factor in the improved survival of these patients.     

Inflammatory pseudotumor of the spleen: Ultrasound and computed tomographic findings

Inflammatory pseudotumor of the spleen is an extremely rare benign lesion characterized by a wide spectrum of nonspecific inflammatory and reparative changes.The ultrasound and computed tomographic (CT) findings of inflammatory pseudotumor affecting the spleen in an asymptomatic patient are reported. The CT scanning revealed a partially calcified mass showing a nonhomogeneous enhancement after contrast injection. After 3 min of bolus administration, an unenhanced central area, which corresponds to a focal area of fibrosis, was demonstrated.     

Computed tomographic distinction of submucosal lipoma and adenomatous polyp of the colon

Described here is a patient with 2 large pedunculated colonic tumors detected by barium enema radiography. By computed tomography (CT) 1 was found to be a submucosal lipoma characterized by oval shape, smooth demarcation, and homogeneous density with a CT number of –68 HU, whereas the other was an adenomatous polyp with slightly fuzzy outline and a much higher CT number. This case indicates that CT can be a definitive diagnostic modality for distinguishing between a colonie lipoma and other solid or cystic tumor of the colon.     

Demonstration of an internal pancreatic fistula by computed tomography

The computed tomographic demonstration of a mediastinal pseudocyst communicating with the pancreatic duct in a patient with severe acute pancreatitis is reported. An awareness of this communication was essential in planning the appropriate surgical management.     

Asymptomatic nonspecific serum hyperamylasemia and hyperlipasemia: spectrum of MRCP findings and clinical implications

We assessed the magnetic resonance cholangiopancreatographic (MRCP) findings in patients with asymptomatic, mild elevations of serum amylase and lipase levels to determine whether there might be a pathoanatomic cause for these laboratory abnormalities. MRCP was performed in 633 consecutive patients. Of these, 54 (8.5%) images were obtained in patients with asymptomatic serum hyperamylasemia and hyperlipasemia. MRCP was performed on a 1.0-T MR system; breath-hold gradient-recall, half-Fourier acquisition, and rapid acquisition with relaxation enhancement sequences were obtained. Findings were verified by follow-up, biopsy, or surgery. One-sided, large-sample z tests were used to compare the incidence of abnormalities between the study and control groups (579 patients). The pancreas appeared abnormal on MRCP in 31 patients (57%), including the pancreas divisum in 10 patients (18.5%). Other findings included morphologic changes compatible with chronic pancreatitis in nine patients (16.6%) and a healed pancreatic laceration, juxtapapillary duodenal diverticulum, papillary sclerosis, intraductal pancreatic lithiasis, and hemochromatosis in one patient each (1.9%). Small cystic lesions (< 1 cm) within the pancreas were seen in 15 patients (27.8%). In eight patients, these were associated with other abnormalities (pancreas divisum in three patients, chronic pancreatitis in four, and pancreatic laceration in one). No malignancy was diagnosed. The incidences of normal examination (p = 0.01), pancreas divisum (p < 0.005), and a small cystic lesion (p = 0.01) as solitary findings in this subgroup of patients were significantly higher when compared with the remainder of the studied population. Investigation of asymptomatic patients with nonspecific hyperamylasemia and hyperlipasemia by means of MRCP yielded pancreatic findings in more than 50% of these patients. Pancreas divisum was found more often than expected in the general population.     

Computed tomographic evaluation and staging of cecal carcinoma

The preoperative computed tomographic (CT) scans of 14 patients with biopsy-proven primary adenocarcinoma of the cecum were reviewed to assess clinical presentation, CT findings, and value of staging by CT. The correlation of CT evidence for tumor invasion beyond the bowel wall with histopathology had predictive value of negative examination of 33% with sensitivity of 78%. More importantly, the correlation of metastatic nodal involvement by CT had predictive value of negative examination of 22% with sensitivity of only 12%. Of chief concern was the involvement of pericolic and mesenteric nodal chains that were not discernible by CT. Computed tomographic tumor staging was accurate in 57% of cases and upgraded in 43%. This study concludes that, although predictive values of positive CT examination are high, CT tends to underestimate disease extent.     

Pancreatic transplants: secretin-stimulated MR pancreatography

Background

Our study was aimed to evaluate the functional status of pancreatic transplants using dynamic MR pancreatography after secretin stimulation.

Methods

Thirteen asymptomatic patients previously submitted to isolated pancreas (n = 6) or combined kidney–pancreas (n = 7) transplantation, with enteric-portal pancreatic drainage, underwent MR examination at 1.5 T using a phased-array coil. After the acquisition of axial and coronal T1- and T2-weighted sequences, dynamic MR pancreatography was performed using a coronal breath-hold, thick-slab (40–60 mm), single-shot T2-weighted fast spin-echo sequence. After the intravenous administration of secretin (Secrelux^®, Sanochemia; 1 cU/kg body/weight), a single-slice image acquisition was repeated every 30 s up to 15 min. We estimated the calibre changes of the pancreatic ductal system and the filling of the donor’s duodenum on the basis of pancreatic secretion after secretin stimulation, also evaluated by using a mean signal intensity/time histogram in a chosen region of interest including the transplanted pancreas and the connected small bowel.

Results

All patients well tolerated the examination, and no side effects were reported after secretin administration. In 12/13 cases, a significant increase (more than 1 mm) in the diameter of the mean pancreatic duct was observed after secretin stimulation; in all patients, a noticeable filling of the duodenal graft was demonstrated during dynamic MR pancreatography on both qualitative and quantitative analyses.

Conclusions

Dynamic MR imaging after secretin administration allows non-invasive evaluation of exocrine function of the pancreatic transplants and could be used to differentiate patients with graft rejection from those with normal graft function.

     

Intraoperative sonography of hepatocellular carcinoma: Detection of lesions and validity in surgical resection

Eighty-six hepatocellular carcinomas (HCCs) in 67 patients were examined by intraoperative sonography. Sensitivity for detecting tumors with intraoperative sonography was compared with sonography, computed tomography (CT), hepatic angiography, and CT after intraarterial injection of iodized poppy-seed oil (Lipiodol-CT). The overall sensitivities were 76% with sonography, 86% with CT, 89% with angiography, 96% with Lipiodol-CT, and 98% with intraoperative sonography. The differences in sensitivity between intraoperative sonography and sonography (p < 0.01), CT (p < 0.01), and angiography (p < 0.05) were significant. In 35 lesions smaller than 2 cm, the sensitivities of Lipiodol-CT and intraoperative sonography were high (91 and 94%, respectively). In operating field, tumors were invisible in 36 (42%) and nonpalpable in 31 of 86 cases (36%). In 35 tumors smaller than 2 cm, invisible tumors were 66% and nonpalpable tumors were 63%. However, 84 of 86 cases (98%) could be localized with intraoperative sonography.These results suggest that intraoperative sonography is the final diagnostic imaging procedure before surgical resection of tumors and in cases of invisible and nonpalpable tumors in the operating field, this procedure is mandatory to improve surgical results.     

Computed tomographic findings of ruptured hepatic malignancy

Massive hemorrhage from ruptured hepatocellular carcinoma is uncommon. We report our experience in three cases of ruptured hepatocellular carcinoma diagnosed by computed tomography (CT). CT was useful in detecting ruptured hepatocelluar carcinoma showing the parenchymal tumor per se, defining the extent of the hematoma, and showing serial density changes with the age of the hematomas.     

Age-related morphology of the normal pancreas on computed tomography

Abdominal computed tomographic scans were performed on a group of 360 patients between the ages of 20 and 80 years. The anteroposterior diameter of the pancreatic head, body, and tail, the age-related ratio of vertebral body-pancreas diameter, and the external and internal contours of the organ were analyzed. The age-related changes in the pancreas were compared with known anatomical findings.     

Pancreatic metastases of renal cell carcinoma: Report of two cases

Two cases of renal cell carcinoma, metastatic to the pancreas, are presented. The lesions were hypoechoic with ultrasound examination, and were mixed iso- and hypodense with computed tomography. Angiography was performed in one case, and showed a typical hypervascular pattern of the metastatic tumor.