Double-contrast Technique Research Articles

Contrast agents in acute myocardial infarction.

The experimental design in examination of acute myocardial infarctions should be valid in terms of flow, perfusion and re-flow after intervention. The contrast agents concentration in experimental studies can be measured by microdialysis. We have assessed the usefulness of different extracellular and blood pool contrast agents for visualization of the area at risk in coronary artery occlusions. The double contrast technique, where Dy-DTPA-BMA was combined with Gd-DTPA-BMA yielded a superior infarct visualization. Blood pool agents for example NC100/150 injection is also promising in first path myocardial perfusion imaging.

Enteroscopy as a Tool for Diagnosing Gastrointestinal Bleeding Requiring Blood Transfusion

Iron-deficiency anemia secondary to gastrointestinal blood loss is a common cause of hospitalization. In many cases, the bleeding site cannot be defined despite thorough routine examination of the gastrointestinal tract. The aim of this study was to evaluate push enteroscopy as a diagnostic tool in patients with severe anemia, secondary to recurrent gastrointestinal bleeding, that required management by transfusion. Thirty-five consecutive push enteroscopy investigations were performed in 1998 and 1999 on 25 patients (15 men, 10 women). Mean age was 57 +/- 16 years (range, 33-83). All patients had received blood transfusions because of pronounced anemia secondary to gastrointestinal bleeding. Before push enteroscopy, all patients had been investigated with esophagogastroduodenoscopy, colonoscopy, and small-bowel radiography using the double contrast technique; no bleeding site was found. In addition, 10 of 25 patients had been investigated beforehand with 99mTc-labelled red blood cell scintigraphy, and 5 of 25 with scintigraphy for Meckel diverticulum. Two patients were also investigated with angiography before the push enteroscopy, and in six patients an additional total intraoperative enteroscopy was performed, preceded by a new colonoscopy, esophagogastroduodenoscopy, and push enteroscopy. A bleeding site was disclosed in 15 of 25 (60%) patients. In 7 of 25 patients (28%) the bleeding site was found in the stomach or esophagus. even though the patients had undergone one or two esophagogastroduodenoscopies earlier with normal findings. Total intraoperative enteroscopy identified a bleeding site in four of six (67%) patients studied. Two patients had bleeding hemangiomas that were resected surgically. Two patients had small intestinal adenomas, one with adenocarcinoma in situ. Push enteroscopy performed with an overtube inserted under fluoroscopic guidance is an important diagnostic tool in patients in whom conventional examinations do not disclose bleeding sites. Interestingly, 28% of patients had bleeding within reach of the gastroscope, indicating that a new upper endoscopy should be recommended before push enteroscopy is performed. When no positive findings are seen on push enteroscopy and the patient is affected by severe, recurrent iron-deficiency anemia, total intraoperative enteroscopy should be considered.

Diagnosis of colorectal neoplasms at double-contrast barium enema examination.

The double-contrast barium enema examination has been recognized as an option for colorectal cancer screening in Americans with average risk who are greater than 50 years of age. The purpose of this article is to review the principles for diagnosing colorectal neoplasms on double-contrast images and the spectrum of findings associated with these lesions. Colonic polyps can be sessile or pedunculated; their appearance depends on whether they are located on the dependent or nondependent wall of the bowel. Villous tumors may be flat, lobulated lesions, also known as "carpet" lesions, that are characterized by a finely nodular or reticular surface pattern, without a discrete mass. Colonic carcinomas may manifest as plaquelike, polypoid, semiannular ("saddle") or annular lesions. Colonic neoplasms sometimes are more difficult to detect in the region of the ileocecal valve or the distal rectum or in patients with severe diverticulosis. Careful double-contrast technique and meticulous scrutiny of the images therefore are required to optimize detection of these lesions.

Loss of urocystolith architectural clarity during in vivo radiographic simulation versus in vitro visualization.

Urocystoliths of 9 mineral types from 434 canine patients submitted to the University of Minnesota Urolith Bank were imaged in a urinary bladder phantom. Imaging techniques simulated were survey radiography and double contrast cystography. Morphologic characteristics visually observed in vitro or by interpretation of high-resolution specimen radiographs were compared to those seen using the simulated in vivo imaging techniques. Shape characteristics that were accurately detected > or = 25% of the time on simulated survey or double contrast radiography were faceted, irregular, jackstone, ovoid, and round. Surface characteristics that were accurately detected > or = 25% of the time on simulated survey or double contrast radiography were rough, smooth, and smooth with blunt tips. Internal architecture characteristics that were accurately detected > or = 25% of the time on simulated survey or double contrast radiography were lucent center, random-nonuniform, and uniform. Shapes such as bosselated, faceted-ovoid, and rosette; surfaces such as botryoidal, and knife-edged; and internal architecture characteristics such as dense center, dense shell, laminated, and fissures were of almost no value either due to poor detectability or poor accuracy of recognition. Based on optimized simulated survey and double contrast radiographic procedures, it appears that a number of shape, surface, and internal architecture characteristics may be of limited or no value in discriminating among urocystolith mineral types under clinical circumstances. Shapes and surfaces were more accurately characterized by the simulated double contrast technique, but for internal architecture, the simulated survey radiographic technique seemed slightly superior overall.

Commemorating the Publication of Volume 30 of the Japanese Journal of Clinical Oncology: Where are We Heading?

Japanese Journal of Clinical Oncology (JJCO) made its first appearance in January 1971, 29 years ago. In the very first issue, a photo of Dr Masaru Kuru is printed with a brief note about his contribution to the foundation of the Journal. Dr Kuru was the first Director of the National Cancer Center (NCC) Hospital and the third President of NCC, who is considered to have initiated clinical practice and its research on cancer at the NCC. Unfortunately, Dr Kuru had passed away before publication of the first issue. However, it was he who initiated the publication of JJCO with a strong belief that the journal would become an important means of introducing significant achievements of Japanese researchers and clinicians in the field of clinical oncology to the world. Some people wondered, of course, if there was any sense in publishing an English language journal on clinical oncology in Japan. There were already several journals in Europe and in the USA to which Japanese clinical oncologists could send their papers. However, Dr Kuru and some staff of the NCC emphasized the importance of the first English journal on this subject from Japan and their aspiration was embodied by the support of staff of the NCC Hospital and some other scientists. The late Dr Kempo Tsukamoto, the fourth President of the NCC, carried out the intentions of Dr Kuru and served as the first Editor-in-Chief from 1971 to 1974. In Volume 1 of JJCO, there can be found an article on the double-contrast technique in detecting and making a diagnosis of early gastric cancer (1). There is no doubt that the development of double-contrast radiography greatly contributed to the efficient detection of early gastric cancer. This example well illustrates that JJCO aimed at publishing experience and knowledge of Japanese oncologists in English so that such information could be shared with the world. Successive Editors and supporting staff endeavored to increase submissions of quality papers not only from the NCC but also from all over Japan. The late Dr Shichiro Ishikawa, the sixth President of the NCC, succeeded Dr Tsukamoto and served as Editor-in-Chief for 15 years from 1971. After being published biannually for the first 10 years, it became quarterly in 1983 and bimonthly in 1991 as the number of submissions increased (2). Dr Takashi Sugimura, the seventh President of the NCC, was the successor to Dr Ishikawa from 1986 and was the Editor until 1995. He made great efforts to accept papers of basic research with relevance to clinical oncology, which helped to expand the scope of the journal and enrich the contents. The gradual increase in the number of submissions might also indicate that Japanese oncologists, who used to consider a ‘Japanese’ journal to be underdeveloped and preferred established English journals, started to recognize it as being fully fledged. The journal became indexed in Current

Preoperative staging of colorectal carcinoma

Carcinoma of the colorectum is one of the most frequent neoplasias, with an incidence of 40 in 100,000. For the effective use of new, differentiated, less invasive treatment options, exact preoperative staging of the tumor is essential. The introduction of endosonography in rectal tumor staging allows for exact differentiation of the rectal wall layers and thus of tumor stages 1-3 with median accuracy of 89%. Magnetic resonance imaging of the rectum, especially in double-contrast technique, can also be employed in high and stenosing tumors and leads to an average accuracy of 85% for the stages 1-4. Computed tomography is the method of choice in screening for metastases. In lymph node staging, all modalities show only moderate accuracy around 75%.

Screening for simultaneous esophageal primary tumors: esophagoscopy vs esophagography.

The incidence of second esophageal primary tumors in patients diagnosed as having squamous cell carcinoma of the head and neck varies in the literature. However, in large series, an incidence of about 1% to 2% is commonly reported. This relatively low overall incidence has led some authors to question the traditional use of panendoscopy, including the use of either rigid or flexible esophagoscopy to screen for simultaneous second primary tumors of the esophagus in patients with head and neck cancer. Arguments in this regard cite the exposure of most patients to unnecessary additional risk from potential complications and prolonged operating time associated with endoscopy, as well as reduced cost-effectiveness from the routine use of such procedures in which the overall positive yield is low. In addition, an increased survival advantage in the small percentage of patients with head and neck cancer diagnosed as having a simultaneous esophageal malignancy vs those patients who are subsequently diagnosed at a later date as having an esophageal primary lesion has not been demonstrated in retrospective studies, and prospective studies specifically addressing this issue are currently lacking. Barium swallow has been demonstratedtobearelativelysafeandinexpensiveprocedurethat iseasilyperformedandhasbeendescribed in the radiological and thoracic surgery literature as having a diagnostic accuracy of greater than 90% in identifying thepresenceofesophagealpathological features. Levine et al found a sensitivity rate of esophagography of 96%inaseriesof50patientswithcarcinomaof theesophagusandesophagogastric junction. In addition, this studyreviewedanadditional2484patientswhounderwentbariumesophagographyovera1-yearperiod.Endoscopywasrecommendedin26patients (1%) to rule out malignant tumor, 11 (42%)ofwhomwereeventuallyfound to have cancer. Those authors subsequently concluded that barium studies, particularly those using doublecontrast techniques, achieved good sensitivityaswell as satisfactorypositive predictive yield in those cases in whichendoscopywasrecommended. Although it might be expected that the sensitivity of esophagography decreases in cases of early esophageal malignancies, the use of esophagography to detect even relatively small esophageal lesions also finds some support within the literature. Moss et al assessed the accuracy of esophagrams in the detection of small esophageal carcinoma (,3.5 cm). In this article, the radiographic studies of 35 patients, 11 of whom showed evidence of small esophageal carcinomas with the remainder having either benign lesions or normal findings, were presented without accompanying history to 4 clinical radiologists. Although the exact diagnosis was made in only 8 (73%) of 11 patients with carcinoma, abnormal results indicating the need for further endoscopy were detected in 10 (94%) of 11 patients with small esophageal carcinoma, supporting esophagography’s role in the detection of smaller and presumably earlierstage esophageal malignancies. Nino-Murcia et al carried out a double-blind prospective study of 182 patients diagnosed as having head and neck carcinoma, 148 of whom underwent both esophagography and esophagoscopy in an effort to compare the 2 procedures in the detection of simultaneous esophageal carcinoma. Concordance of findings between the 2 procedures was found in 86% of patients. One case of simultaneous esophageal cancer was found in this series and was detected by both methods. FurtherAmit Agrawal, MD Barry L. Wenig, MD, MPH

Crohn's disease of the upper gastrointestinal tract

Although Crohn's disease (CD) is generally found in the ileum and/or colon, since the 1960s it has become evident that this chronic inflammatory disorder of unknown aetiology can affect the whole gastrointestinal tract from mouth to anus. In 0.5–13% of patients with ileocolonic CD the disease occurs in the upper gastrointestinal tract as well (i.e., from mouth through jejunum). With the radiological double-contrast technique, however, early signs of upper gastrointestinal CD may be detected in 20–40% of patients with ileocolitis. On the other hand, histologically evaluated biopsies from the lower oesophagus, body of the stomach, gastric antrum and the duodenal bulb of patients with Crohn's disease from whom the upper gastrointestinal tract is normal, according to X-ray or endoscopy may reveal lesions, which are considered to be pathologically diagnostic. Jejunal involvement occurs in 4–10% of patients with ileitis, ileocolitis or colitis. In early studies biopsies of apparently normal buccal mucosa from patients with Crohn's disease showed a significant correlation between the activity of the disease, as defined by the Crohn's Disease Activity Index, and the number of plasma cells containing IgM, suggesting a generalized activated humoral defence system during relapse. A diagnosis of Crohn's disease of the upper gastrointestinal tract can be achieved by combining recognition of clinical, roentgenographic, and endoscopic features. Provided that other causes of granulomatous involvement of the gastrointestinal tract can be excluded, non-caseating granulomas are generally accepted as the histological proof of Crohn's disease. When Crohn's disease does involve the upper gastrointestinal tract, there is nearly always concomitant disease in the small bowel or colon. Compared to patients with an ileocolonic localization, patients with Crohn's disease in the upper gastrointestinal tract more frequently have colic-like abdominal pain and/or cramps, nausea and anorexia as presenting symptoms and are younger at onset of the disease. Medical therapeutic principles are the same as for Crohn's disease elsewhere in the gastrointestinal tract. Absolute indications for surgical treatment are massive bleeding, progressive stenosis, and extensive fistula formation.

Simultaneous in vivo visualization and localization of solid oral dosage forms in the rat gastrointestinal tract by magnetic resonance imaging (MRI).

Bioavailability of orally administered drugs is much influenced by the behavior, performance and fate of the dosage form within the gastrointestinal (GI) tract. Therefore, MRI in vivo methods that allow for the simultaneous visualization of solid oral dosage forms and anatomical structures of the GI tract have been investigated. Oral contrast agents containing Gd-DTPA were used to depict the lumen of the digestive organs. Solid oral dosage forms were visualized in a rat model by a 1H-MRI double contrast technique (magnetite-labelled microtablets) and a combination of 1H- and 19F-MRI (fluorine-labelled minicapsules). Simultaneous visualization of solid oral dosage forms and the GI environment in the rat was possible using MRI. Microtablets could reproducibly be monitored in the rat stomach and in the intestines using a 1H-MRI double contrast technique. Fluorine-labelled minicapsules were detectable in the rat stomach by a combination of 1H- and 19F-MRI in vivo. The in vivo 1H-MRI double contrast technique described allows solid oral dosage forms in the rat GI tract to be depicted. Solid dosage forms can easily be labelled by incorporating trace amounts of non-toxic iron oxide (magnetite) particles. 1H-MRI is a promising tool for observing such pharmaceutical dosage forms in humans. Combined 1H- and 19F-MRI offer a means of unambiguously localizing solid oral dosage forms in more distal parts of the GI tract. Studies correlating MRI examinations with drug plasma levels could provide valuable information for the development of pharmaceutical dosage forms.

Value of arthro-CT in decision for arthroscopic or open stabilization in ventral shoulder instability

A prospective study was performed on 30 patients with anterior instability of the shoulder to assess the diagnostic value of preoperative arthro-CT. One special diagnostic problem was the definition of diagnostic criteria for arthroscopic or open surgery. Arthro-CT of the shoulder was performed with a double-contrast technique. Visualization of labral tears, bony lesions, glenohumeral ligaments and disruption of the rotator cuff was registered. Findings of arthro-CT were verified by diagnostic arthroscopy. Therapy consisted of either arthroscopic or open surgery depending on the lesion pattern found in diagnostic arthroscopy. The most common cause of anterior instability (90% of cases) was damage of the ventro-caudal labral complex, which was diagnosed by arthro-CT with a sensitivity of 93% and a positive predictive value of 93%. Specificity and negative predictive value were reduced to 33%; the overall accuracy was 87%. In all, 16 patients were successfully treated using arthroscopic stabilization because whereas 14 patients required open surgery because diagnostic arthroscopy contraindicated an arthroscopic approach. The preoperative arthro-CT failed to define all criteria mandatory for the decision for arthroscopic or open surgery because pathoanatomy of the joint was not sufficiently demonstrated with the current technique of arthro-CT.

Optimizing joint-imaging: (CT)-arthrography.

The technique of CT arthrography and arthrotomography of the major joints is discussed. Also, the types of contrast media, double or single contrast technique, film-screen combinations, injection techniques and additional pain testing are discussed.

Preoperative staging of rectal carcinoma using double-contrast MR imaging. Technical aspects and early clinical experiences.

To improve preoperative staging of rectal carcinoma with MR imaging, using a double-contrast technique. Imaging was performed in 12 patients before and after i.v. injection of Gd-DTPA and rectal administration of a superparamagnetic contrast medium, mainly containing magnetite. The diagnostic information was evaluated and compared with findings at surgery and histopathological analysis. The superparamagnetic contrast medium enema caused a distension of the rectum and intraluminal signal void, whereas Gd-DTPA enhanced the mucosa in T1-weighted images. This allowed an evaluation of the normal rectal wall and separation of the mucosa, tunica muscularis and perirectal space in all cases, which was not possible in T1- or T2-weighted precontrast images. The rectal carcinoma could be delineated and tumor invasion to the rectal wall determined in all cases. The findings in postcontrast MR corresponded with the findings at histopathological examination in 11 of 12 patients. The histopathological examination in one patient revealed metastases (< 1 cm) in regional lymph nodes, too small to be identified in pre- or postcontrast MR images. Double-contrast-enhanced MR imaging allows evaluation of the normal rectal wall and preoperative staging of rectal carcinoma.

69.胃ル〜チン前壁二重造影法の手技と工夫(第24回秋季学術大会 一般研究発表予稿集)

69.胃ル〜チン前壁二重造影法の手技と工夫(第24回秋季学術大会 一般研究発表予稿集)

Arthrography of the glenohumeral joint: experience with a non-ionic dimeric contrast agent and future perspectives

The role of conventional arthrography versus computed tomography (CT) arthrography of the glenohumeral joint using iotrolan was evaluated in patients with different shoulder problems. In addition, a diagnostic combination of conventional and CT arthrography was compared with magnetic resonance (MR) arthrography of the glenohumeral joint. Two diagnostic protocols were used. Protocol 1: conventional followed after 30 min by CT arthrography of 37 joints using a double contrast technique with iotrolan 300. Protocol 2: conventional followed after 90–180 min by MR arthrography in 20 patients using a single-contrast technique with 10 ml iotrolan 300 and 1 ml gedopentetate dimeglumine 500 mM. Ten patients also underwent CT arthrography. Neither patient group experienced contrast-related complications. Image quality was good for all conventional arthrograms, excellent in 45/47 CT arthrograms and good in 20 MR arthrograms. CT and MR arthrography were diagnostically valuable in many patients. We conclude that glenohumeral joint evaluation should be perfomed first using conventional or CT arthrography. Iotrolan has proven to be highly reliable and safe in these applications. Iotrolan in combination with gadopentetate dimeglumine, permits MR arthrography following completion of the standard examinations if necessary.

Microradiographic Anatomy of the Explanted Rat Colon

The colon of 32 healthy Sprague-Dawley rats was studied microradiographically. The colonic arterial distribution of 18 rats was examined after injecting barium sulfate into the isolated aorta. The mucosal surface in 9 rats was studied using double-contrast technique after colon explantation. In 5 animals arterial and mucosal studies were carried out simultaneously. The radiographic thickness of the colonic wall was measured using a comparative microscope. The specimens were observed, photographed and examined histologically. Unlike the cecum and distal colon which, when insufflated, do not have mucosal folds, the proximal colon exhibits folds in an oblique direction corresponding to that of the arteries, and the colonic wall in this region is thicker. Comparison between arterial and mucosal microradiographic anatomy and wall thickness enables the proposition of a simple nontopographic division of the rat colon into cecum, proximal colon and distal colon.

Diagnosis and treatment of early gastric cancer

Background Because of the high incidence of gastric cancer among the Japanese, group examination for gastric cancer was proposed and the double contrast technique was developed as a method of X-ray diagnosis. Methods The endoscope has developed from the early gastrocamera to the fiberscope and to the latest electroscope using CCD. Owing to the advancement of the diagnostic methods, early gastric cancer has been discovered throughout Japan in remarkably higher numbers, from a mere 217 in 1961 to the cumulative number of 24,847 until 1980. Results Among the 1180 patients with gastric cancer who underwent surgery in our hospital between 1971 and 1989, 364 had early phase gastric cancer limited to the mucosa and their relative survival rate was 100.3% during the first 10 years. On the other hand, the survival rate of the patients with cancer that reached the serous membrane was as low as 22.2%. The survival rate greatly depends on the presence or absence of lymph node metastasis. Among all cases of gastric cancer, the 10-year survival rate of the 828 patients without lymph node metastasis was 97.6%, whereas that of the 213 patients with lymph node metastasis was 38.7%. If early gastric cancer can be detected before lymph node metastasis, a radical cure of the cancer is possible solely by local excision or by treatments using an endoscope without the need of purgation of lymph nodes. 613 patients with early gastric cancer were examined for lymph node metastasis. There was no lymph node metastasis in patients having the elevated type cancer with the major bosselation diameter smaller than 2.5 cm and those having the depressed type cancer with the major depression diameter smaller than 2.0 cm that does not show ulcerative changes. These 44 patients underwent non-invasive treatments. The results of the endoscopic laser treatment were as follows; the removal of cancer tissue was not complete after the first treatment of 5 of 14 patients with cancer tissues of 21 to 40 mm, (35.7%); the removal was not complete in 4 of 19 patients with cancer tissues of 11 to 20 mm (21.0%); all of the patients with cancer tissues of 10 mm or less were completely cured. The 43 patients who received endoscopic mucosal resection, all with cancer tissues of 10 mm or less, were cured, except for 2 patients with cancer near the pylorus ring. On average, however, the removal of cancer tissue was not complete in 30% of the patients. Conslusions Although the basic treatment of early gastric cancer is the surgical one, less invasive endoscopic treatments are effective in limited cases. However, a thorough examination should be done beforehand in each case as to whether the endoscopic treatment is appropriate and, after treatment, careful observation of the progress is required.

Double-Contrast Enhanced Mr Imaging of Myocardial Infarction in the Pig

Myocardial infarction was induced by ligating a diagonal branch of the left anterior descending artery in 18 pigs. All pigs were sacrificed 6 h after the occlusion. Dysprosium diethylenetriaminepentaacetic acid bismethylamide (Dy-DTPA-BMA, 1.0 mmol/kg) was administered i.v. to 6 pigs, starting 3 min before sacrifice (injection time approximately 1 min). In a second group of 6 pigs, a double-contrast technique was used, consisting of an i.v. injection of gadolinium-DTPA-BMA (0.4 mmol/kg) 2 h before sacrifice, followed by an i.v. injection of Dy-DTPA-BMA (1.0 mmol/kg) 3 min before sacrifice. Six additional pigs, subjected to 6 h of coronary artery occlusion without administration of contrast medium, served as controls. The hearts were excised and imaged with MR. In the control animals, the infarctions demonstrated an increased signal intensity in the proton density- and T2-weighted images. Administration of Dy-DTPA-BMA primarily improved infarct visualization in the proton density- and T2-weighted images, due to reduction of signal intensity in nonischemic myocardium. The double-contrast technique further improved infarct visualization in all sequences.

Double-Contrast Enhanced MR Imaging of Myocardial Infarction in the Pig

Myocardial infarction was induced by ligating a diagonal branch of the left anterior descending artery in 18 pigs. All pigs were sacrificed 6 h after the occlusion. Dysprosium diethylenetriamine-pentaacetic acid bismethylamide (Dy-DTPA-BMA, 1.0 mmol/kg) was administered i.v. to 6 pigs, starting 3 min before sacrifice (injection time approximately 1 min). In a second group of 6 pigs, a double-contrast technique was used, consisting of an i.v. injection of gadolinium-DTPA-BMA (0.4 mmol/kg) 2 h before sacrifice, followed by an i.v. injection of Dy-DTPA-BMA (1.0 mmol/kg) 3 min before sacrifice. Six additional pigs, subjected to 6 h of coronary artery occlusion without administration of contrast medium, served as controls. The hearts were excised and imaged with MR. In the control animals, the infarctions demonstrated an increased signal intensity in the proton density- and T2-weighted images. Administration of Dy-DTPA-BMA primarily improved infarct visualization in the proton density- and T2-weighted images, due to reduction of signal intensity in nonischemic myocardium. The double-contrast technique further improved infarct visualization in all sequences.

Post-operative computed tomographic imaging of the shoulder joint

Between 1984 and 1990 312 patients underwent surgery for habitual or recurrent shoulder dislocation. Out then, 65 had a post-operative CT examination. This retrospective study was launched to demonstrate the value of CT in post-operative shoulder imaging. In most cases, CT was done using standardised techniques without contrast medium. Except in 4 cases, an intra-articular double-contrast technique was used. Evaluation was focused on 41 cases after implantation of a wedged bone graft in cases of primary or secondary flat glenoid or widening of a small glenoid with cortical consoles and bone block. The results demonstrate the effectiveness of standardised CT technique in that all necessary information concerning stabilisation of the shoulder joint, sufficient implant of bone grafts and assessment of correct inclination after osteotomy were obtained.

The role of barium enema in detecting colorectal disease. A radiologist's perspective.

The single-contrast barium enema examination remains useful for patients with acute diseases such as bowel obstruction, diverticulitis, appendicitis, and fistulas. It is also the procedure of choice for those patients who are too elderly, debilitated, or ill to cooperate with the maneuvers necessary for a double-contrast examination. The double-contrast technique is more sensitive than the single-contrast technique for detection of polyps, early inflammatory bowel disease, and lesions of the rectum. In the older population, there has been an increase in the incidence of colonic polyps and carcinomas in the right side of the colon. This emphasizes the need to examine the entire colon in these patients. The double-contrast barium enema is a safe, accurate, and cost-effective tool for accomplishing this. It is also recommended as the initial procedure in the examination of patients with positive results on fecal occult blood testing.