Specificity of 99mTc-pertechnetate in scintigraphic diagnosis of Meckel's diverticulum: review of 100 cases.

Numerous reports in the recent literature have questioned the value of abdominal scanning with pertechnetate in the diagnosis of Meckel's diverticulum. In an attempt to evaluate further the specificity of pertechnetate in this condition, the clinical data and scintigrams of 100 patients with suspected Meckel's diverticulum were reviewed. The scintigram correctly identified Meckel's diverticulum before operation in seven of eight patients. One false-negative study occurred in 33 patients who underwent laparotomy. Conditions suggested as possible causes of false-positive studies (hydronephrosis, arteriovenous malformations, and intussusception) were found to give negative scans.

Computed tomography of the large bowel and appendix.

Computed tomography (CT) of the colon is useful in assessment of patients with colonic disease because the entire bowel wall, extraluminal tissues, and adjacent solid organs can be directly visualized. Patients with advanced stage colorectal carcinoma can be reliably identified with CT. This information can assist in surgical planning for intraoperative irradiation and placement of a hepatic artery infusion catheter. CT is an important imaging modality in the postoperative evaluation for recurrent rectal cancer after abdominoperineal resection. CT-guided biopsy often can provide histologic proof of suspected tumor recurrence or metastasis. Patients with diverticulitis or appendicitis can be identified by CT. The extent of disease and the nature of the inflammatory process--factors potentially affecting patient management--can be directly visualized. Percutaneous aspiration and drainage of abscess collections can be curative in appropriately selected patients.

Chemotherapy-related hepatotoxicity causing imaging findings resembling cirrhosis.

In this article, we describe three women in whom changes in the liver resembling cirrhosis occurred during systemic chemotherapy for metastatic breast carcinoma. All three patients were treated with tamoxifen as part of their chemotherapeutic regimen. Abnormalities of biochemical liver tests were associated with the development of a cirrhosis-like appearance of the liver on computed tomography. In two of the patients, hepatic metastases were proved at biopsy. The third patient had no radiologic evidence of metastatic disease. Chemotherapy for metastatic breast carcinoma may cause striking morphologic changes in the liver that resemble cirrhosis. Of importance, these changes should not be mistaken for the development or progression of liver metastases. Alternatively, because of the changes produced by chemotherapeutic agents, detection of metastases on computed tomography alone may be more difficult. Supplementary magnetic resonance imaging may be helpful in selected cases.

Roentgenographic simulation of colonic cancer by benign masses in Crohn's colitis.

Crohn's colitis has recently been shown to predispose the patient to cancer of the colon. Unfortunately, many of the manifestations of colonic malignancy, such as polypoid intraluminal masses and strictures, can be simulated roentgenographically by Crohn's colitis. We present five patients in whom this diagnostic difficulty arose. As established by total or subtotal colectomy, none proved to have malignancy; instead, pronounced transmural inflammation and, in two cases, multiple large pseudopolyps were found to account for the roentgenographically indeterminate lesions. These findings exemplify the difficulty in roentgenographic diagnosis of colonic mass lesions in patients with Chrohn's colitis.

Intraluminal duodenal diverticulum. Report of two cases and review of the literature.

Diverticula rarely occur within the lumen of the duodenum. They arise near the papilla of Vater and extend distally. The diverticulum is lined on both sides with duodenal mucosa, and its eccentric opening is usually proximal in the sac. The diverticulum results from incomplete recanalization of the intestinal lumen after the proliferative epithelial stage in the 7-week embryo and represents either a remnant of one of two channels formed during recanalization or a distal ballooning of a congenital duodenal diaphragm. Although the patient with a diverticulum may be asymptomatic, most patients present with abdominal pain and obstructive symptoms; pancreatitis and gastrointestinal bleeding may be associated with the diverticulum. Barium study shows a characteristic radiolucent halo that represents the wall of the diverticulum. Surgery should be approached with caution because injury to the papilla is a hazard, and in children, coexisting congenital anomalies may be present.

Renal cell carcinoma metastatic to the pancreas: clinical and radiological features.

OBJECTIVE: To review the clinical features, computed tomographic (CT) appearance, and treatment outcomes in a case series of patients with renal cell carcinoma (RCC) metastatic to the pancreas. PATIENTS AND METHODS: We retrospectively reviewed the records of 23 patients (15 men and 8 women) with RCC metastatic to the pancreas, detected by CT examination between 1986 and 1996. All patients had undergone a previous nephrectomy for RCC. RESULTS: Isolated mild elevation in liver function test results (in 5 patients) or in serum amylase level (in 8 patients) was observed. New-onset diabetes was detected in 3 patients. The CT characteristics of the pancreatic metastases generally resembled those of primary RCC with well-defined margins and greater enhancement than normal pancreas with a central area of low attenuation. The mean interval between resection of the primary RCC and detection of the pancreatic metastases was 116 months (range, 1-295 months). In 18 patients (78%), the pancreatic metastases were diagnosed more than 5 years after nephrectomy. The pancreas was the initial metastatic site in 12 patients (52%). Survival was shortened with higher tumor grade (mean survival time of 41 months and 10 months in patients with grade 2 and 3, respectively). Surgical resection was carried out in 11 patients (7 distal and 3 total pancreatectomies and 1 distal pancreatectomy followed 4 years later by total pancreatectomy), with 8 patients alive at a mean follow-up of 4 years, 6 of whom remained free of recurrence. Overall, 12 patients (52%) were alive at a mean of 42 months after diagnosis of metastatic disease. CONCLUSIONS: The appearance of metastatic RCC lesions in the pancreas closely resembles the appearance of primary RCC on CT images. Pancreatic metastases from RCC are frequently detected many years after nephrectomy. Patient survival correlates with tumor grade. Histologic analysis of pancreatic masses in patients with a history of resected primary RCC is important since the prognosis for RCC metastatic to the pancreas is much better than that for primary pancreatic adenocarcinoma.

Initial clinical experience with computerized tomography of the body.

Computerized tomography of the body, now possible with an instrument that can complete a scan rapidly enough to permit patients to suspend respiration, adds an important new dimension to radiologic diagnosis. Cross-sectional antomy is uniquely reconstructed to provide accurate diagnostic information for various disorders throughout the body.

Computed tomography of the retroperitoneal space.

Computed body tomography is an easily accomplished method that precisely displays the normal and pathologic anatomy of the retroperitoneal space. Suspected retroperitoneal disorders, which are often clinically confusing or obscure, can now be detected or excluded with remarkable accuracy. Few innovations in radiology have more effectively fulfilled such a conspicuous need.

Mercury toxicosis caused by ingestion of a blistering compound in a horse.

Mercury toxicosis by ingestion was diagnosed in a 3-year-old Quarter Horse mare with a history of anorexia and signs of abdominal discomfort. Ten and 9 days prior to admission, an inorganic mercuric blistering agent has been applied for topical treatment of dorsal metacarpal disease. At referral, signs of depression, dependent edema, pollakiuria, nonproductive cough, and oral ulceration were noticed. Laboratory data were consistent with renal dysfunction. Mercury content of blood and urine was high, confirming the diagnosis. The horse responded to intensive care, consisting primarily of IV fluid treatment, and mercury-chelating agents. However, acute laminitis developed, and the owners elected to euthanatize the horse 18 days after mercury exposure. Necropsy findings included renal tubulonephrosis and ulcerative colitis and enteritis. Mercury concentration was highest in kidney and liver tissues. The potential for mercury toxicosis in horses currently exists, and although the prognosis is grave, some horses may recover with appropriate treatment and long-term supportive medical care.

CT of pancreatic neoplasms. Part I: Adenocarcinoma.

Adenocarcinoma of the pancreas has been one of the most formidable, diseases of the past half century, consistently ranking among the leading causes of death from cancer in the industrialized world. The profound diagnostic difficulties that characterized this neoplasm during the early decades of that era have largely given way to radiologic advances of recent decades. Daunting therapeutic challenges persist, however, as few individuals in whom this common form of pancreatic cancer develops are aware of their illness before the disease has advanced beyond the stage of curability. The benefits of recent diagnostic break-throughs in pancreatic adenocarcinoma are nonetheless immense. Although their proportion remains disappointingly small, an increasing number of persons owe their lives to the detection of pancreatic carcinoma at a stage amenable to complete surgical resection. Far more patients benefit from timely detection, accurate staging, and nonsurgical biopsy of an unresectable neoplasm. Still more, perhaps, benefit from the confident exclusion of pancreatic cancer as a source of worrisome symptoms. The goal of this discussion is to help the radiologist achieve full diagnostic potential in examining patients who have, or who are suspected to have, adenocarcinoma of the pancreas. As the leading method in the diagnostic advance on pancreatic cancer, computed tomography (CT) is given predominant attention. The principles of diagnostic interpretation, however, are based on an understanding of the neoplasm itself. In that respect, the manifestations of pancreatic adenocarcinoma as displayed by CT are in large measure just as pertinent to any other worthwhile method of pancreatic imaging.

CT of pancreatic neoplasms. Part II: The unusual tumors.

The pancreas gives rise to a remarkable variety of neoplasms other than ductal adenocarcinoma. Although no individual type of tumor in this category is prevalent enough to qualify as common, most types are currently encountered with a frequency far greater than that in decades of the recent past. This change is largely the result of the expanded use of contemporary abdominal imaging. The unusual tumors of the pancreas vary greatly in their biologic behavior and, accordingly, in their clinical consequences and therapeutic requirements. Accurate diagnosis, therefore, can be of considerable clinical relevance. Not only is it worthwhile to distinguish one type of unusual pancreatic tumors from another, it is perhaps of even greater consequence to distinguish the unusual tumors from ordinary pancreatic adenocarcinomas. The goals of this discussion are to expand radiologic awareness of these uncommon but interesting pancreatic neoplasms and to increase familiarity with their diagnostically salient features.