PURPOSE:To determine if intravenously administered contrast material improves overall reader confidence in the assessment of the colon, large-bowel wall conspicuity, and diagnostic accuracy in the detection of colorectal polyps and cancers at computed tomographic (CT) colonography.MATERIALS AND METHODS:Two hundred patients underwent CT colonography in both supine and prone positions. A five-point scale was used to assess the effect of contrast enhancement on overall reader confidence and bowel wall conspicuity. Eighty-one patients underwent CT colonography with complete colonoscopic or surgical correlation; diagnostic accuracy was compared in 48 patients who received contrast material and 33 who did not.RESULTS:Bowel preparation was ideal in 38 (19%) of 200 patients. Enhanced prone CT images had significantly better scores for reader confidence (4.9 +/- 0.1 vs 4.6 +/- 0.1, P: <.005) and bowel wall conspicuity (4.6 +/- 0.2 vs 4.2 +/- 0.2, P: <.005) compared with those of nonenhanced prone images despite no significant difference in bowel distention (3.8 +/- 0.2 vs 3.9 +/- 0. 1, P: =.8). Enhancement significantly improved the ability to depict medium (6-9-mm) polyps (75% vs 58%, P: <.05). Three large (10-19-mm) polyps were detected only with contrast enhancement; two remained submerged despite dual positioning.CONCLUSION:The use of intravenously administered contrast material significantly improved reader confidence in the assessment of bowel wall conspicuity and the ability of CT colonography to depict medium polyps in suboptimally prepared colons.

Despite an overall reduction rate, gastric cancer (GC) is still a leading malignancy World wide and in some areas in Italy the incidence is almost as high as in Japan.In high risk areas Pepsinogen A and C (PGA and PGC) and PGAlPGC ratio have been used for screening purposes while we have previously reported that Gastrin (G)xPGA index was also a useful cancer predictor (1).With this in mind we carried out a field study in an open population aged more than 40 years in a village in the North-East of Italy, previously reported at high risk for both GC and gastric lymphoma (2).Serum G, PGA and PGC were evaluated by radioimmunoassay in 186 subjects and they were divided into 3 groups at different risks of GC: Group I = high risk (PGA<20 ng/ml, and/or PGAlPGC<2 and/or Gx-PGA30 and/or PGAI PGC>3 and/or GxPGA>15(0).Upper GI endoscopy was performed for screening purposes and for histologic evaluation of the gastric mucosa (H&H, 2 biopsies from antrum, corpus, fundus and cardias, respectively) in all subjects.Both MALT lymphoma and gastric dysplasia (GO) were regarded as neoplastic lesions.Results are expressed as Sensitivity (SS), Specificity (SP), Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of the markers and Odd Ratio (OR) for neoplastic lesions.RESULTS: 12 out of the 186 subjects were excluded for previous gastric surgery for peptic disease; 31 (17.8%)tested positive for Group I, 22 (12.6%) for Group 2 and 121 (69.6%) for Group 3. No GC was detected by endoscopy.Histological examination showed 9 gastric malignancies: 8 in Group I (MALT lymphoma n=l; dysplasia n=7)(x2 =27.8,

OBJECTIVE:We evaluated the clinical usefulness of endoluminal CT colonography after an incomplete colonoscopy.SUBJECTS AND METHODS:We prospectively studied 40 patients in whom the cecum could not be reached endoscopically despite adequate bowel preparation. Endoluminal CT colonography (120 kVp, 120 mA, 3-mm collimation, pitch of 2, 1.5-mm interval reconstruction) was performed within 2 hr of incomplete colonoscopy. Two-dimensional multiplanar reformatted images and three-dimensional endoluminal images were analyzed. Twenty-six patients (65%) underwent barium enema immediately after endoluminal CT colonography. We analyzed colonic distention; duration of endoluminal CT colonography; patient tolerance; number of colonic segments seen at colonoscopy, endoluminal CT colonography, and barium enema; and reasons for incomplete colonoscopy as well as colonic and extracolonic findings.RESULTS:Duration of endoluminal CT colonography was 14.2 +/- 4.6 min (mean +/- SD). Endoluminal CT colonography was better tolerated than colonoscopy or barium enema (p < .001). Probable causes for incomplete colonoscopy were identified at endoluminal CT colonography in 74% of 40 patients. Baseline colonic distention in the region of the transverse and right colon was considered adequate before additional air insufflation; however, the addition of air significantly enhanced colonic distention throughout the entire colon (p < .001). Endoluminal CT colonography adequately revealed 96% of all colonic segments; in comparison, barium enema adequately revealed 91% of all segments (p < .05).CONCLUSION:In patients with incomplete colonoscopy, endoluminal CT colonography successfully showed the previously unrevealed colon in more than 90% of patients. Endoluminal CT colonography is a rapid, well-tolerated technique that provides clinically useful colonic and extracolonic information and should be considered for all patients who undergo incomplete colonoscopy.

Changes in the environment in which clinical medical education takes place in the United States has profoundly affected the quality of the learning experience. A shift to out-patient based care, minimization of hospitalization time, and shrinking clinical revenues has changed the teaching hospital or "classroom" to a degree that we must develop innovative approaches to medical education. One solution is the Virtual Patient Project. Utilizing state-of-the-art computer-based multimedia technology, we are building a library of simulated patient encounters that will serve to fill some of the educational gaps that the current health care system has created. This project is part of a newly formed and unique organization, the Harvard Medical School-Beth Israel Deaconess Mount Auburn Institute for Education and Research (the Institute), which supports in-house educational design, production, and faculty time to create Virtual Patients. These problem-based clinical cases allow the medical student to evaluate a patient at initial presentation, order diagnostic tests, observe the outcome and obtain context-sensitive feedback through a computer program designed at the Institute. Multimedia technology and authoring programs have reached a level of sophistication to allow content experts (the teaching faculty) to design and create the majority of the program themselves and to allow students to adapt the program to their individual learning needs.

Erythromyoin (E) a macrolide antibiotic, has previously been leported to accelerate gastric emptying throught stimulation of motilin receptor.In vitro studies have shown that motilin and E stimulate pepsinogen secretion directly in the chief cells isolated from guinea pig stomach (Gastroenterology 1993;104:1030-36) but there is no informations about the effects of E on gastric acid secretion in humans.Aim of the study: determine the effect of I.V E on basal, and stimulated acid secretion by pentagastrin or by meal.