Visual survey of cancer dissemination: classic patterns on helical CT. Abdomen and pelvis.

Helical CT evaluation of the abdomen and pelvis can be challenging in the cancer patient. This pictorial essay illustrates the important sites of neoplastic dissemination in the abdomen and pelvis. We will emphasize the classic CT appearance of several selected sites and indicate, where appropriate, the primary lesions usually associated with each.

Dose and pitch relationship for a particular multislice CT scanner.

OBJECTIVE: With single-slice helical CT, an increased pitch can decrease the radiation dose to the patient if all other parameters are constant. The purpose of this study was to determine whether the same relationship holds for a particular multislice helical CT system (Somatom Plus 4 VZ multislice helical CT scanner, version A11A) in our department. CONCLUSION: The measured radiation dose to the phantom was identical for all pitch selections on the multislice helical CT system we tested. This unexpected result was because of an automatic proportionate increase in the tube current when the pitch selection was increased. Radiologists and physicists should exercise caution when extrapolating dose reduction strategies from single-slice to multislice helical CT systems, and they must acquire a detailed understanding of the multislice helical CT scanner of their chosen manufacturer.

Current concepts in the diagnosis and management of renal cell carcinoma: role of multidetector ct and three-dimensional CT.

Renal cell carcinoma is the most common primary tumor of the kidney, with more than 30,000 new cases diagnosed in the United States each year. With the widespread use of cross-sectional imaging, many tumors are detected incidentally. Single- and multidetector computed tomography (CT) have helped refine the diagnostic work-up of renal masses by allowing image acquisition in various phases of renal enhancement after intravenous administration of a single bolus of contrast material. The scanning protocol should include unenhanced CT followed by imaging during the corticomedullary and nephrographic phases of enhancement. The nephrographic phase is the most sensitive for tumoral detection, while the corticomedullary phase is essential for imaging the renal veins for possible tumoral extension and the parenchymal organs for potential metastases. Knowledge of the tumoral stage at the time of diagnosis is essential for prognosis and surgical planning. The accuracy of CT for staging has been reported to reach 91%, with most staging errors related to the diagnosis of perinephric extension of tumor. Three-dimensional CT provides the urologist with an interactive road map of the relationships among the tumor, the major vessels, and the collecting system. This information is particularly critical if the tumor extends into the inferior vena cava and if nephron-sparing surgery is being planned.

Left adrenal vein localization by 3D real-time volume-rendering CTA before laparoscopic nephrectomy in living renal donors.

BACKGROUND: We investigated whether the left adrenal vein could be consistently localized on three-dimensional (3D) real-time volume-rendering computed tomographic angiographic (CTA) mapping in a group of living renal donors before laparoscopic nephrectomy. METHODS: Sixty-six consecutive potential renal donors were referred for CTA vascular mapping before laparoscopic donor nephrectomy. Thirty-three patients were examined on a single-detector helical CT scanner and the other 33 were examined on a multidetector unit. In each patient, arterial phase and venous phase volumetric data sets were acquired after the intravenous injection of 150 cc of non-ionic contrast material. Three radiologists reviewed the data sets at a free-standing workstation after the application of 3D volume-rendering software and reached a consensus on whether the left adrenal vein was visualized and, when seen, its position relative to the abdominal aorta. RESULTS: The left adrenal vein was found in 92.5% of the 66 donors (91% in the single-detector group and 94% in the multidetector group). The junction of the left adrenal vein and left renal vein averaged 5.2 mm (range = 0-13 mm) from the left lateral wall of the abdominal aorta. CONCLUSION: Three-dimensional real-time volume-rendering CTA with single-detector and multidetector scanners permits consistent localization of the left adrenal vein in more than 90 % of prospective living renal donors.

Three-dimensional volume-rendering CT angiography in vasculitis: spectrum of disease and clinical utility.

Spiral computed tomographic angiography (CTA) coupled with three-dimensional volume-rendering image processing is a less invasive alternative to conventional catheter angiography. The technique has been used successfully in a variety of vascular diseases. In this pictorial essay, we review the CTA findings in selected cases of vasculitis. Technical considerations and the potential clinical value of this method are discussed.

Visual survey of cancer dissemination: classic patterns on helical CT of the neck and thorax.

Important sites of metastasis from intrathoracic and extrathoracic primary neoplasms are depicted on helical CT of the neck and thorax. This pictorial essay reviews several of these key sites of dissemination. For each, we illustrate the typical or classic appearance on helical CT and note the commonly associated primary malignancies.

Interventricular septal mass: an unusual manifestation of sarcoidosis demonstrated on helical computed tomography.

The diagnosis of cardiac sarcoidosis can be difficult to establish. We present the case of a 33-year-old woman in whom a contrast-enhanced helical computed tomographic examination of the thorax demonstrated an interventricular septal mass. Subsequent open biopsy confirmed cardiac sarcoidosis.

A prospective evaluation of transvaginal sonography for detection of ovarian disease.

OBJECTIVE: Despite the expanding role of transvaginal sonography in routine gynecologic examinations, as well as in screening for ovarian cancer, recent reports have noted problems when using the procedure for detecting ovarian masses and visualizing the ovaries in postmenopausal women. Our study was designed to assess prospectively the capability of transvaginal sonography in evaluating the ovary and detecting adnexal masses. SUBJECTS AND METHODS: Transvaginal sonography was used to examine 113 ovaries in 59 women within 72 hr before gynecologic surgery. Ovarian size and echo texture were assessed, and a search was made for adnexal masses. Sonograms were interpreted without knowledge of the clinical history or results of physical examination, and the sonographic findings were compared with surgical and pathologic data. RESULTS: In the 22 premenopausal patients, 16 (76%) of 21 histologically normal ovaries were identified on sonograms, but only 13 (59%) of 22 adnexal masses. Lesions as large as 177 cm3 were not detected. In the 37 postmenopausal patients, 12 (20%) of 59 normal ovaries and six (54%) of 11 adnexal masses were identified. Five malignant masses (largest, 113 cm3) were not detected. CONCLUSION: In this selected population, our ability to detect normal postmenopausal ovaries and ovarian masses was suboptimal in a number of cases. Practitioners should be aware of potential limitations in the use of this technique alone to evaluate the ovary.

Distribution of metastases in breast carcinoma: CT evaluation of the abdomen.

To determine the frequency and distribution of extrahepatic and extraskeletal metastases in patients with breast carcinoma, the abdominal CT scans of 260 consecutive patients were systematically evaluated. Extrahepatic and extraskeletal metastases were demonstrated in 26 patients (10%). Confirmation of findings was made by biopsy, autopsy, or by demonstration of progression or regression of disease. Twelve patients (4.6%) demonstrated metastases to the stomach, eleven of whom presented with a linitis plastica pattern. Retroperitoneal and/or mesenteric adenopathy was noted in 10 patients (3.8%), of whom three demonstrated associated hydronephrosis and one demonstrated associated biliary obstruction. Ascites was seen in 14 (5.4%) and peritoneal carcinomatosis in 7 (2.6%). Genitourinary involvement included metastases to the kidney (one case), ureter (one), and uterus (one). Direct invasion of the diaphragm by adjacent pleural metastases (two cases) as well as a soft tissue metastasis (one case) was also demonstrated. Metastases to the ovaries, adrenals, or pancreas could not be identified. Although lesions to the liver and skeleton account for the largest group of metastases from breast carcinoma seen in the abdomen, one should be aware of the potential for other locations of metastatic disease.

Feasibility of digital teleradiology for imaging evaluation of patients with acute right upper quadrant abdominal pain.

To assess the utility of a commercially available digital teleradiology system in evaluating patients with acute pain in the right upper quadrant, hard-copy images from 100 examinations (50 hepatobiliary scintigrams and 50 sonograms of the right upper quadrant) were digitized, transmitted via standard telephone lines, and viewed remotely on a video monitor. Video and hard-copy interpretations were then compared for degree of concordance. For the scintigraphic studies, hard-copy and video images were equal in demonstrating gallbladder and bile duct activity. Video images failed to depict the presence of bowel activity in one case. Gallstones were depicted equally well on hard-copy and video sonographic images. The video interpreters overestimated the presence of abnormal hepatic parenchyma and overlooked one case of right hydronephrosis. The video interpretations of the scintigrams and sonograms showed an overall error rate of 4%, comparable to the rate obtained when radiographs are interpreted remotely with digital teleradiology systems.

Internal mammary lymphadenopathy: imaging of a vital lymphatic pathway in breast cancer.

The prognostic significance of metastases to the internal mammary lymph nodes in patients with breast carcinoma has long been recognized. While ipsilateral dissection of axillary nodes remains a popular staging strategy for breast cancer, surgical sampling of the upper anterior intercostal spaces, a tedious procedure, has been largely abandoned. Diagnostic imaging of the parasternal lymphatic pathway is a useful and noninvasive alternative to surgical staging. This report reviews the pertinent regional anatomy and illustrates the criteria for diagnosing internal mammary lymphadenopathy by means of lateral chest radiography, computed tomography, high-resolution sonography, magnetic resonance imaging, and radionuclide lymphoscintigraphy.

Parasternal sonography of the internal mammary vessels: technique, normal anatomy, and lymphadenopathy.

Metastasis to the internal mammary lymph nodes adversely affects the disease-free interval and long-term survival in women with breast carcinoma. Since staging of disease in this lymphatic chain is rarely performed at the time of definitive surgical treatment, noninvasive methods have been advocated. The authors present their preliminary experience with a sonographic technique for evaluating the internal mammary lymph nodes, artery, and vein. Longitudinal and transverse images of the first through fourth parasternal rib interspaces were acquired with a 5.0- or 7.5-MHz linear-array real-time system. The method was evaluated prospectively in 36 control subjects and in seven patients (six with metastatic breast cancer and one with lymphocytic lymphoma) who had enlarged internal mammary lymph nodes at thoracic computed tomography (CT). The longitudinal scans routinely demonstrated the internal mammary vessels in the upper interspaces. Lymphatic structures were not identified in the control group. In contrast, sonographic findings corresponding to the CT findings of lymphadenopathy were present in all seven patients. The authors believe that parasternal sonography is a promising technique that merits further study.

CT of the stomach and duodenum.

CT has become an important tool in the diagnosis and management of diseases that affect the stomach and duodenum. By depicting the bowel lumen, wall, and extramural structures, CT can provide unique information that complements standard air contrast radiography and endoscopy. Proper scanning methods and knowledge of normal anatomy are necessary for optimal results. We utilize the gas contrast technique for organ-specific examination in patients with known or suspected gastroduodenal disease. Gastric adenocarcinoma is an important indication for CT evaluation. Unfortunately, early hopes that CT could accurately stage gastric cancer have not been realized. CT is not as accurate as laparotomy in staging early gastric cancer, primarily owing to its inability to detect small peritoneal implants, diagnose metastases in normal-sized lymph perigastric nodes, and predict pancreatic invasion. Nevertheless, CT retains an important role in depicting gross metastatic disease and guiding percutaneous biopsy, particularly in patients who are deemed poor surgical candidates or have undergone prior gastric resection. A variety of conditions other than primary gastric adenocarcinoma produce recognizable abnormalities on CT. Gastric lipoma, leiomyosarcoma, and varices have a distinctive appearance. Others, including gastritis and uncomplicated peptic ulcer, produce nonspecific gastric wall thickening. Endoscopic correlation and biopsy are required for specific diagnosis in these cases. The duodenum, by virtue of its location in the anterior pararenal compartment of the retroperitoneum, may be involved by numerous benign and malignant conditions. In blunt trauma, complicated pancreatitis, and peptic ulcer disease, as well as primary and metastatic malignancy, CT can provide data that may alter patient management.

CT demonstration of the appendix in asymptomatic adults.

We prospectively examined 103 consecutive adults (67 women, 36 men; mean age: 58.7 years) referred for abdominal and pelvic computed tomography (CT) in whom there was no history of right lower quadrant symptoms or appendectomy. Contiguous 5-mm CT images through the pericecal region were obtained in each subject, once routine scanning was completed. Three radiologists reviewed all CT images and reached a consensus on appendiceal visualization and the quantity of intraperitoneal fat. Statistical methods were applied to the collected data to seek significant associations between a visualized appendix and the following factors: patient age, sex, intraperitoneal fat grade, and the presence of oral contrast in the cecal lumen. The appendix was definitely visualized in only 45 of the 103 patients (43.7%). Analysis of variance revealed no statistically significant correlation between a CT-demonstrated appendix and the four variables examined. The clinical implications of these findings are discussed.

Induction of thoracic malignancy in inorganic dust pneumoconiosis.

Pulmonary carcinoma is now the leading cause of death due to cancer in men and women. Aside from cigarette smoking, occupational exposure to carcinogens is the most important cause of lung cancer, accounting for up to one third of all cases. The following article is a review of occupationally induced thoracic neoplasms with an emphasis on those related to the inhalation of inorganic dust. After introducing some basic terms, describing the research methods, and reviewing the process of carcinogenesis, current information on the relationship between exposure to asbestos, synthetic mineral fibers, silica, and other nonfibrous mineral dusts and the development of lung cancer and malignant mesothelioma of the pleura will be presented. The goal of this article is to provide the practicing radiologist with knowledge and insight into this difficult area.

Internal mammary lymphadenopathy in breast carcinoma: CT appraisal of anatomic distribution.

Internal mammary lymph nodes are an important site of occult metastasis in clinically operable and recurrent breast carcinoma. Anatomic distribution of enlarged internal mammary nodes in patients with breast cancer was analyzed in a review of thoracic computed tomographic studies of 219 women with operable, advanced, or recurrent cancer. Enlarged nodes were observed in 45 patients (20.5%), 32 with unilateral and 13 with bilateral involvement. Mean nodal diameter was 1.95 cm (0.6-6.0 cm). Lymphadenopathy was limited to one anterior intercostal space in 43%, two spaces in 26%, three spaces in 22%, and four spaces in 9%. Solitary or dominant nodal enlargement was centered at the first space in 14%, second space in 60%, and third space in 26%. Isolated lymphadenopathy in the fourth or fifth spaces was not observed. Metastases to internal mammary nodes frequently occur at multiple levels and are most common in the second and third spaces. This finding concurs with current surgical practice when internal mammary nodes are sampled.

Acute diverticulitis of the cecum and ascending colon diagnosed by computed tomography.

Between June 1984 and August 1985, computed tomography (CT) was performed upon seven patients with diverticulitis of the cecum and ascending colon who presented with acute right lower quadrant symptoms of unknown origin. Three of these patients had undergone an appendectomy, while in the remaining four patients, the history and physical findings were atypical of acute appendicitis. CT findings suggestive of acute diverticulitis including thickening of the intestinal wall and pericolonic inflammation were present in all seven patients. In four patients, the colonic inflammation was limited to the segment of ascending colon superior to the ileocecal valve. In one patient, the inflammation involved both the ascending colon and the cecum, while in the two remaining patients, the inflammatory changes were limited to the cecum. An associated diverticular abscess was present in five patients and all were correctly identified preoperatively by CT. One patient in whom the diagnosis of uncomplicated diverticulitis of the ascending colon was made on the basis of the CT scan, was successfully managed nonoperatively with antibiotics. Five patients required a right hemicolectomy for perforated diverticulitis with abscess. The remaining patient underwent a right hemicolectomy for recurrent episodes of acute diverticulitis. Our experience suggests that CT is useful in the early diagnosis of diverticulitis of the cecum and ascending colon.

Actinomycosis: CT findings in six patients.

Actinomycosis is an uncommon disease with clinical and radiographic findings that overlap those of other inflammatory and neoplastic conditions. A retrospective review of CT scans in six proved cases revealed a spectrum of findings, including soft-tissue mass with various degrees of infiltration and abscess formation. Administration of IV contrast material was helpful in defining the loculations of the abscess in two cases. Areas of involvement included the neck (two cases), liver (one case), abdominal wall (one case), thorax (one case) and kidney and retroperitoneum (one case). CT findings of a soft-tissue mass in the neck, lungs, or abdomen, with or without a draining sinus or fistula, raise the possibility of actinomycosis in patients with clinical findings that suggest a subacute or chronic inflammatory process.