Gastrointestinal response to minute doses of glucagon

Transient failure of opening of the lower oesophageal sphincter on upright oesophagrams: radiographic and clinical findings

The purpose of our study was to determine the frequency, radiographic features, and clinical importance of transient failure of opening of the lower oesophageal sphincter (LOS) on upright double-contrast views of the oesophagus. A computerized search of radiology records identified 16 patients who had transient failure of opening of the LOS on upright views from biphasic oesophagrams or upper gastrointestinal tract examinations using high-density barium but normal opening of the LOS on prone views using low-density barium. The radiographic findings were reviewed and correlated with the clinical and manometric findings. In all cases, barium studies revealed tapered, beaklike narrowing of the distal oesophagus on upright double-contrast views, with a normal-appearing distal oesophagus, normal opening of the LOS, and intact peristalsis on prone single-contrast views. Only seven patients (44%) had dysphagia. Five of these patients had clinical follow-up, and the dysphagia improved or resolved without specific treatment for LOS dysfunction in four. The remaining patient had persistent dysphagia, but this individual had polymyositis as the likely cause for his dysphagia. Manometry revealed incomplete relaxation of the LOS in two patients and normal relaxation in one. Our experience suggests that failure of opening of the LOS may be observed as a transient finding of little clinical importance on upright double-contrast views of the oesophagus using high-density barium, with normal opening of the LOS on prone single-contrast views using low-density barium. It is important to be aware of this finding, so that it is not mistaken for achalasia or other abnormalities of the distal oesophagus.

Intravenous glucagon: does it optimize evaluation of the gastrointestinal tract on helical CT?

Forty outpatients were randomized into two groups of 20. Twenty patients received 1 mg of intravenous glucagon and the other 20 did not. Three radiologists evaluated the bowel using a qualitative score and mean scores for each bowel level were compared. A different radiologist measured the maximal diameter of bowel at seven levels. There were no significant differences in qualitative or quantitative data for the two groups. Intravenous glucagon is therefore not routinely recommended for helical CT of the abdomen.

Retrospective motion correction in digital subtraction angiography: a review

Digital subtraction angiography (DSA) is a well-established modality for the visualization of blood vessels in the human body. A serious disadvantage of this technique, inherent to the subtraction operation, is its sensitivity to patient motion. The resulting artifacts frequently reduce the diagnostic value of the images. Over the past two decades, many solutions to this problem have been put forward. In this paper, we give an overview of the possible types of motion artifacts and the techniques that have been proposed to avoid them. The main purpose of this paper is to provide a detailed review and discussion of retrospective motion correction techniques that have been described in the literature, to summarize the conclusions that can be drawn from these studies, and to provide suggestions for future research.

Clinical uses of gut peptides

OBJECTIVE

The authors review clinical applications of gut-derived peptides as diagnostic and therapeutic agents.

SUMMARY BACKGROUND DATA

An increasing number of gut peptides have been evaluated for clinical use. Earlier uses as diagnostic agents have been complemented more recently by increasing application of gut peptides as therapeutic agents.

METHOD

The authors conducted a literature review.

RESULTS

Current experience with clinical use of gut peptides is described. Initial clinical applications focused on using secretomotor effects of gut peptides in diagnostic tests, many of which have now fallen into disuse. More recently, attention has been directed toward harnessing these secretomotor effects for therapeutic use in a variety of disorders, and also using the trophic effects of gut peptides to modulate gut mucosal growth in benign and malignant disease. Gut peptides have been evaluated in a variety of other clinical situations including use as adjuncts to imaging techniques, and modification of behaviors such as feeding and panic disorder.

CONCLUSIONS

Gut peptides have been used successfully in an increasing variety of clinical conditions. Further refinements in analogue and antagonist design are likely to lead to even more selective agents that may have important clinical applications. Further studies are needed to identity and evaluate these new agents.

Dose reduction of hyoscine-N-butylbromide for double-contrast barium meal examinations--a prospective randomized study

A search of the literature suggests that the conventional 20 mg dose of intravenous hyoscine-N-butylbromide (HBB) for smooth muscle relaxation in double-contrast barium meal (DCBM) studies is largely empirical. This study analysed the merits of three different doses (5 mg, 10 mg, 20 mg) in the performance of routine DCBMs. One hundred and twenty DCBM examinations were prospectively and randomly allocated to receive one of three doses. Three parameters were measured for each examination: gastroduodenal distension, delay in gastric emptying and gastric antrum overlapping with barium-filled duodenal loops. Almost half the examinations using 5 mg produced undesirable duodenal-gastric overlay. Unacceptable early flooding of the duodenal bulb with barium was seen mostly with doses of 5 mg and 10 mg. Overall, the best results were obtained with 20 mg. The continued use of 20 mg HBB in routine DCBMs is recommended.

Radiographic examination of the stomach and duodenum: comparison of single-, double- and biphasic-contrast methods

We compared retrospectively three groups of 150 patients who had undergone radiologic examinations of the stomach and duodenum. Each group was examined with a different barium suspension and radiographic technique: single-contrast (SC), double-contrast (DC), or biphasic-contrast (BC). The radiographs of each study were evaluated for technical quality and visualization of lesions. The number of X-ray exposures, films, and the amount of fluoroscopic time for each study were tabulated. The total radiation dose and cost for each technique were calculated. The BC examinations required the greatest number of radiographic exposures and X-ray films; however, cost was highest for the DC method. Fluoroscopy was significantly longer during the DC procedures, and the total radiation dose was also highest with this technique. Gaseous distention and barium coating of the stomach were equally good for the BC and DC groups, but X-ray penetration of the barium suspension during compression filming was significantly better in the BC and SC groups. Areae gastricae were most frequently seen during the BC studies and artifacts from excess secretions, barium flocculation or gas bubbles were least commonly present using this technique. Significantly more lesions were demonstrated in the stomach with the BC technique than with the other methods; however, the number of lesions found in the duodenum was the same for each technique.

The effects of glucagon and glucagon-(1-21)-peptide on antroduodenal motility in healthy volunteers

Since it has been argued that the spasmolytic effect of glucagon is related to the first 21 N-terminal amino acid residues, and not to the complete molecule, we have compared the effects of glucagon-(1-21)-peptide (G-(1-21) and glucagon on human antroduodenal motility. Glucagon and G-(1-21) were given as bolus injections to 30 healthy volunteers equally allocated into five groups. Each subject received two doses; one was placebo, 0.25, 0.5, 1.0 or 2.0 mg of glucagon, the other was an equimolar doses of G-(1-21) (placebo, 0.175, 0.35, 0.70 or 1.4 mg of G-1-21). The first injection was given during phase II of a migrating motility complex (MMC), and the next during the following phase II. Contractile activity was recorded using an oral tube with one sidehole positioned in the antrum and two in the duodenum. We confirmed that glucagon decreases the number of contractions in the antrum and duodenum and that normal phase II activity was restored within 20-40 minutes proportionally to the amount of the drug given. G-(1-21) did not change antroduodenal motility nor did it affect the phase II pattern in any of the groups. Neither were any side effects encountered. G-(1-21) does not seem to be an alternative to glucagon and other spasmolytic drugs for obtaining relaxation of the antroduodenal area.

Gastroduodenal peptic ulcers, duodenal adhesions, and upper gastrointestinal motility disturbances in patients who have undergone cholecystectomy

The frequency of duodenal and gastric ulcer disease, the thickness of the pyloric muscle, and adhesions of the duodenum were evaluated in a routine, consecutive, prospective autopsy series of 100 patients, and the length of the pyloric canal, adhesions of the duodenum, and motility disturbances in the upper gastrointestinal series were studied in a separate radiologic material of 69 symptomatic patients with cholecystectomy in their history. Both series were compared with matched unoperated controls. The frequency of active gastric ulcers and ulcer scars was observed to be increased and that of active duodenal ulcers and ulcer scars decreased among the cholecystectomized patients in the autopsy series (p = 0.01 in both cases). This difference was not as pronounced when only active ulcers were included, but for active duodenal ulcers the difference was still significant (p = 0.04). One-fourth of the cholecystectomized patients but none of the controls had severe adhesions of the duodenum. In the autopsy series the thickness of the pyloric muscle and in the radiologic series the length of the radiologic pyloric canal were thickened/lengthened in an average of 26%/11% in patients who had undergone cholecystectomy (p less than 0.001 and p less than 0.10, respectively). The lengthening of the pyloric canal was in significant positive correlation with the motility disturbance/adhesion score of the upper gastrointestinal series.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of intravenous digital subtraction angiography to conventional aortography in patients with abdominal aortic aneurysm

Evaluation of intravenous digital subtraction angiography (IV DSA) in patients with abdominal aortic aneurysm was performed by obtaining catheter aortograms immediately before DSA studies in ten patients. Diagnostic images were obtained in nine of ten digital subtraction examinations. Although repeat injections were necessary in six DSA and three conventional aortography cases for adequate imaging of both cephalad and caudal extension of the aneurysm, average contrast dose was 53 cc (62 cc in standard catheter studies). Renal artery stenosis was diagnosed by DSA in two of three vessels, multiple renal arteries were demonstrated by both modalities in two cases. Digital subtraction and conventional aortographic findings were proved at surgery. Intravenous DSA was shown to be useful in the preoperative evaluation of patients with abdominal aortic aneurysm.

Intravenous digital subtraction angiography of the thoracic and abdominal aorta

Intravenous digital subtraction angiography (IV DSA) is a new imaging modality that utilizes techniques of video image acquisition and computer image manipulation to provide anatomic information about blood vessels and organs. In many ways, it represents an electronic version of classic intravenous and film-subtraction angiography. As a means of imaging the thoracic and abdominal aorta, IV DSA has demonstrated great potential, particularly in vessels originally imaged by the former techniques. We have imaged the aorta in over 300 cases at Brigham and Women's Hospital, either alone, or in combination with other vessels in the course of work-up for vascular disease. Although experience has been limited, intravenous imaging of the aorta can be routinely performed, providing reliable and clinically significant information.