Analysis of air contrast barium enema, computed tomographic colonography, and colonoscopy: prospective comparison.

BACKGROUND: The usefulness of currently available colon imaging tests, including air contrast barium enema (ACBE), computed tomographic colonography (CTC), and colonoscopy, to detect colon polyps and cancers is uncertain. We aimed to assess the sensitivity of these three imaging tests. METHODS: Patients with faecal occult blood, haematochezia, iron-deficiency anaemia, or a family history of colon cancer underwent three separate colon-imaging studies--ACBE, followed 7-14 days later by CTC and colonoscopy on the same day. The primary outcome was detection of colonic polyps and cancers. Outcomes were assessed by building an aggregate view of the colon, taking into account results of all three tests. FINDINGS: 614 patients completed all three imaging tests. When analysed on a per-patient basis, for lesions 10 mm or larger in size (n=63), the sensitivity of ACBE was 48% (95% CI 35-61), CTC 59% (46-71, p=0.1083 for CTC vs ACBE), and colonoscopy 98% (91-100, p<0.0001 for colonoscopy vs CTC). For lesions 6-9 mm in size (n=116), sensitivity was 35% for ACBE (27-45), 51% for CTC (41-60, p=0.0080 for CTC vs ACBE), and 99% for colonoscopy (95-100, p<0.0001 for colonoscopy vs CTC). For lesions of 10 mm or larger in size, the specificity was greater for colonoscopy (0.996) than for either ACBE (0.90) or CTC (0.96) and declined for ACBE and CTC when smaller lesions were considered. INTERPRETATION: Colonoscopy was more sensitive than other tests, as currently undertaken, for detection of colonic polyps and cancers. These data have important implications for diagnostic use of colon imaging tests.

Localization of occult bronchogenic carcinoma by bronchography.

Bronchography is seldom recommended today to localize radiographically and bronchoscopically occult bronchogenic carcinoma. We report a case in which bronchography promptly localized such a tumor that had been occult to multiple bronchoscopies and chest computed tomograms (CTs). The patient is free of recurrence 32 months after lobectomy. Bronchography should be considered when bronchoscopies and CT fail to reveal a radiographically occult carcinoma.

Parietal pleural plaques, asbestos bodies, and neoplasia. A clinical, pathologic, and roentgenographic correlation of 25 consecutive cases.

An investigation was made to correlate autopsy and roentgenographic findings of pleural plaques with occupational exposure to asbestos and occurrence of respiratory tract tumors. Of the 434 autopsies performed over a 2 1/2 year period, 25 (5.8 percent) had pleural plaques but no gross evidence of parenchymal fibrosis. Review of the posterior-anterior chest roentgenograms using the International Labor Office criteria for classification of pneumoconiosis (1980) revealed that only seven of the 25 cases had detectable pleural thickening or calcification, which demonstrates the poor sensitivity of standard x-ray films. There was no detectable difference in frequency of known or presumed exposure to asbestos between the pleural plaque cases and controls as determined by occupational information obtained from chart review. Asbestos bodies were identified in lung tissue digests from all 25 cases with pleural plaques, and exceeded the normal range for our laboratory in 14 cases (56 percent). Of the 25 cases with pleural plaques, four also had bronchogenic and three had laryngeal carcinoma. The prevalence of bronchogenic carcinoma in patients with plaques was not different from those without plaques (p greater than 0.50). However, the association between plaques and laryngeal carcinoma was highly significant (p = 0.004).

Scientific presentations. What to do and what not to do.

An effective scientific presentation requires skill, experience, and effort. In planning the presentation, a skilled speaker first forms clear conclusions through analysis of the data, then tailors the details of the proof of these conclusions to the interests and background of the audience. The facts and conclusions are presented in a practiced, specific, clear, and logical manner. It is not the topic or the data alone, but the sympathetic and strategic communication of the material to a particular audience that makes a meaningful presentation.

Carcinoma of the lung with osseous stromal metaplasia.

Calcification has long been a determinant in the radiologic distinction of a benign pulmonary mass. However, rare examples of calcification without ossification in pulmonary adenocarcinoma and ossification in the bronchial carcinoid have led some investigators to warn against this approach. A case of pulmonary adenocarcinoma with stromal ossification is reported herein. The literature is reviewed for neoplasms that exhibit pulmonary ossification either by primary or metastatic lesions. To our knowledge, this case represents the first report of benign osseous stromal metaplasia in the primary lesion of a pulmonary adenocarcinoma.

Preoperative and postoperative CT staging of rectosigmoid carcinoma.

This study reports a 4 year experience using CT for preoperative staging and for evaluation of patients with rectal and sigmoid carcinoma after surgery. All patients were evaluated on a GE 8800 scanner using 1 cm contiguous slices. Only 15 of the 25 preoperative patients were staged correctly. The other 10 patients were understaged by CT. The accuracy of detecting local invasion was 70%, but only seven (35%) of 20 patients had accurate assessment of lymph nodes. The overall accuracy of CT staging in the 46 postoperative patients was 87%, with a sensitivity of 91% and a specificity of 72%. Most recurrences were found in the pelvis; 16 patients had liver metastases, and metastatic disease obstructing the ureters was detected in eight patients. On the basis of these results, it was concluded that CT should not be used routinely to preoperatively stage patients with rectosigmoid carcinoma. However, all patients who have undergone resection for rectal or sigmoid carcinoma should have aggressive CT evaluation including a baseline study at 2-4 months and then follow-up studies at every 6 months for at least 2 years. All new or enlarging masses should have CT-guided biopsies. This approach may prolong survival by detecting early asymptomatic recurrences.

The variable CT appearance of hepatic abscesses.

Fifty computed tomographic (CT) scans in 33 patients with 37 separate episodes of hepatic abscess were reviewed retrospectively. Abnormalities were detected in all but one case (97% sensitivity). However, a characteristic CT appearance of hepatic abscess was not evident. Most intrahepatic foci were solitary, but multiple abscesses were present in 34% of cases. The CT appearance of the lesions varied from well defined, rounded cavities with contents near water density, resembling poorly defined hepatic cysts, to higher-density foci indistinguishable from hepatic neoplasms. In only 19% was gas present within the abscess. Rim enhancement was seen in only 6%. This study suggests that CT is a sensitive test for detecting hepatic abscess but is often nonspecific.

Computed tomography of high density renal cysts.

Eleven patients are described whose computed tomography (CT) examinations showed homogeneous, high density (62-76 Hounsfield units) renal masses. In two patients a hemorrhagic benign cyst was found at surgery. In the remaining nine patients the constellation of CT and clinical findings supported the benign nature of this lesion.

Ascites or pleural effusion? CT differentiation: four useful criteria.

CT can accurately distinguish between ascites and pleural fluid if the four signs described here are all considered in each case. Used individually these signs may be indeterminate or misleading.

Sonography of small renal masses with indeterminant density characteristics on computed tomography.

Nine small renal masses with attenuation coefficients greater than 20 HU on computed tomography (CT) were termed indeterminate for cyst or renal cell carcinoma. Correlative sonography identified the fluid-filled internal architecture in four of five cysts and correctly characterized as solid four small renal cell carcinomas. The sonogram was particularly valuable in assessing masses that were indeterminate on CT when enhancement was equivocal or when intravenous contrast could not be administered. We conclude that sonography is extremely useful as a noninvasive procedure in evaluating the occasional small renal mass with CT number greater than 20 HU.

Pancreatic pseudocyst: comparative evaluation by sonography and computed tomography.

Fifty-four patients were referred to rule out pancreatic pseudocyst. These patients underwent both sonographic and abdominal computed tomographic (CT) examinations for the evaluation of suspected pseudocysts. Among the 54 cases were 24 with proven pseudocysts. CT correctly identified 23 of the 24 pseudocysts with one false-negative and two false-positive studies. With sonography, the studies were technically inadequate in 20 of the 54 patients examined. Sonography correctly diagnosed 18 of the 24 pseudocysts; however, in 10 of these 18 cases sonographic findings were incomplete relative to CT findings. There were one false-negative and three false-positive sonographic studies. On the basis of this study, it was concluded that CT is more accurate than sonography in both diagnosing and demonstrating the extent of pseudocysts of the pancreas.

Computed tomography of the rectum.

CT is an important diagnostic procedure in patients with suspected or known disease of the rectum. Knowledge of proper technique for CT of the rectum, as well as an understanding of normal pelvic anatomy, is essential to its effective use. CT can demonstrate the extent of perirectal and pararectal abnormalities detected on barium enema. While routine preoperative staging of rectal cancer is not justified, CT can be used to solve specific problems. Perhaps the most important role of rectal CT is in evaluating postoperative rectosigmoid cancer patients in an attempt to detect early asymptomatic recurrences and, thereby, prolong patient survival.

Pseudosarcoma of the esophagus: barium swallow and CT findings.

Two new patients with pseudosarcoma of the esophagus are presented with the first report of the findings on computerized tomography (CT). The radiographic appearance in the two patients, with 24 previously reported, is reviewed. Barium esophagograms typically demonstrate a large, elongated polypoid mass in the middle or lower third of the esophagus that distends the lumen at the level of the lesion, but does not produce marked obstruction. There are no specific CT characteristics which differentiate pseudosarcoma from squamous cell carcinoma of the esophagus.

The radiologic evaluation of gross cecal distension: emphasis on cecal ileus.

A retrospective review of plain abdominal radiographs in 46 patients with gross cecal distension (greater than 10 cm) was performed. In 25 (54%) of 46 patients, the cecum was dilated out of proportion to the rest of the colon and was rotated anteromedially. The term cecal ileus is used to describe this situation. Five (20%) of 25 patients with cecal ileus developed perforation. Four of these patients died as a result of the perforation. The risk of perforation was related more to duration of cecal distension than to absolute cecal size. Aggressive decompressive measures, including consideration of cecostomy, appear warranted in patients with gross cecal distension, especially when it is dilated out of proportion to the rest of the colon and has persisted for several days.

Computed tomography for staging esophageal and gastroesophageal cancer: reevaluation.

A reevaluation of computed tomography (CT) for staging carcinoma of the esophagus and gastroesophageal junction was performed in 76 patients. For comparison 26 patients without carcinoma of the esophagus with a normal mediastinum at surgery were included in the evaluation. Four radiologists evaluated the CT scans without knowledge of the diagnosis. After determining if there was an adequate amount of fat, they were asked to evaluate each case for the presence or absence of local invasion and distant metastases. The radiologists correctly identified all 26 normal patients. Eighteen of the 76 carcinoma patients had a paucity of fat, but only six were thought to have truly indeterminate scans. CT correctly identified 40 of the 44 esophageal carcinoma patients with mediastinal invasion and 11 of the 15 patients without invasion (accuracy 88%). CT correctly identified 15 of 19 patients with distant abdominal metastases and 28 of 30 patients without metastases (accuracy 88%). CT was only 50% accurate in predicting the presence or absence of invasion in the 12 patients with gastroesophageal junction tumors and only 58% accurate in predicting distant metastases. CT correctly staged 46 (94%) of 49 patients with esophageal carcinoma but only five (42%) of 12 patients with gastroesophageal junction tumors. These results confirm that CT should be used as a major staging method in all patients with esophageal carcinoma.