Glucagon: common untoward reactions--review and recommendations

Recommendations for MRI technique in the evaluation of pelvic endometriosis: consensus statement from the Society of Abdominal Radiology endometriosis disease-focused panel

Endometriosis is a common entity causing chronic pain and infertility in women. The gold standard method for diagnosis is diagnostic laparoscopy, which is invasive and costly. MRI has shown promise in its ability to diagnose endometriosis and its efficacy for preoperative planning. The Society of Abdominal Radiology established a Disease-Focused Panel (DFP) to improve patient care for patients with endometriosis. In this article, the DFP performs a literature review and uses its own experience to provide technical recommendations on optimizing MRI Pelvis for the evaluation of endometriosis.

Contrast media for fluoroscopic examinations of the GI and GU tracts: current challenges and recommendations

One of the significant challenges facing radiologists who perform and interpret studies of the gastrointestinal and genitourinary systems have been periodic interruptions in the availability of barium and iodinated contrast media specially formulated for gastrointestinal (GI) and genitourinary (GU) studies. These interruptions are due to the US Food and Drug Administration's recent requirement for more stringent documentation of the safety and efficacy of contrast media and the consolidation among contrast manufacturers. Therefore, radiologists may be required to recommend an alternative means of evaluation, such as computed tomography, magnetic resonance, or endoscopy, or they may need to substitute a different formulation of a contrast agent not specifically developed for GI or GU use, for example the utilization of an agent designed and marketed for vascular use. This article reviews the current status of fluoroscopic contrast media, and provides suggestions and recommendations for the optimal and alternative use of contrast media formulations.

MR Imaging of the Prostate Gland

This article discusses MR imaging of the normal prostate and of disease conditions of the prostate including prostatitis, cystic lesions, amyloidosis, calculi, hematospermia, benign prostatic hyperplasia, and malignancy.

Cine MR enterography grading of small bowel peristalsis: evaluation of the antiperistaltic effectiveness of sublingual hyoscyamine sulfate

RATIONALE AND OBJECTIVES

To use a cine balanced steady-state free precession magnetic resonance enterography (cine MRE) pulse sequence to assess the effectiveness of a sublingual (SL) antiperistaltic agent, hyoscyamine sulfate.

MATERIALS AND METHODS

Institutional review board approval was granted with an exemption for informed consent in this Health Insurance Portability and Accountability Act-compliant, retrospective, single-institution study. Of the 288 MRE examinations performed between October 1, 2007 and January 15, 2011, 92 using SL hyoscyamine sulfate for antiperistalsis were included for review, each with cine MRE before and after medication. These 184 cine MRE data sets were randomized, blinded for treatment, and independently reviewed by five attending abdominal radiologists, who rated the degree of whole abdomen bowel motility on each cine MRE data set on a 5-point scale. Pre- and postmedication mean peristalsis ratings, standard deviation, mean difference, and treatment effect sizes were calculated. A repeated measures analysis of variance test was performed using a significance threshold of P = .05. Interobserver reliabilities were also calculated.

RESULTS

Mean peristalsis ratings ranged 2.63-3.34 and 2.36-3.03, before and after medication administration, respectively. The mean differences ranged from 0.22 to 0.46, which are treatment effect sizes of 0.20 to 0.37. The decrease in peristalsis observed by the five reviewing radiologists after SL hyoscyamine sulfate administration was significant (df = 1/182, f = 7.35, P < .01). The interobserver reliabilities were 0.34 for the pretest and 0.33 for the posttest.

CONCLUSIONS

Although cine MRE sequences show decreased bowel peristalsis after the use of SL hyoscyamine sulfate, the small size of the observed treatment effect is likely insufficient to justify its use for MRE.

Miscellaneous pharmaceutical agents in interventional radiology

Interventional radiologists employ a wide variety of drugs on a daily basis to improve patient experiences and outcomes during interventional procedures. The expectation is for the interventionalist to be well-versed in all pharmaceuticals used in the interventional suite. In this article, the authors review the following classes of common miscellaneous pharmaceutical agents used in interventional radiology: vasodilators, vasoconstrictors, antiemetics, bowel antiperistalsis agents, and prothrombotics.

Motion-compensation techniques in neonatal and fetal MR imaging

SUMMARY

Fetal and neonatal MR imaging is increasingly used as a complementary diagnostic tool to sonography. MR imaging is an ideal technique for imaging fetuses and neonates because of the absence of ionizing radiation, the superior contrast of soft tissues compared with sonography, the availability of different contrast options, and the increased FOV. Motion in the normally mobile fetus and the unsettled, sleeping, or sedated neonate during a long acquisition will decrease image quality in the form of motion artifacts, hamper image interpretation, and often necessitate a repeat MR imaging to establish a diagnosis. This article reviews current techniques of motion compensation in fetal and neonatal MR imaging, including the following: 1) motion-prevention strategies (such as adequate patient preparation, patient coaching, and sedation, when required), 2) motion-artifacts minimization methods (such as fast imaging protocols, data undersampling, and motion-resistant sequences), and 3) motion-detection/correction schemes (such as navigators and self-navigated sequences, external motion-tracking devices, and postprocessing approaches) and their application in fetal and neonatal brain MR imaging. Additionally some background on the repertoire of motion of the fetal and neonatal patient and the resulting artifacts will be presented, as well as insights into future developments and emerging techniques of motion compensation.

Colon distension and scan protocol for CT-colonography: an overview

This article reviews two important aspects of CT-colonography, namely colonic distension and scan parameters. Adequate distension should be obtained to visualize the complete colonic lumen and optimal scan parameters should be used to prevent unnecessary radiation burden. For optimal distension, automatic carbon dioxide insufflation should be performed, preferably via a thin, flexible catheter. Hyoscine butylbromide is - when available - the preferred spasmolytic agent because of the positive effect on insufflation and pain/burden and its low costs. Scans in two positions are required for adequate distension and high polyp sensitivity and decubitus position may be used as an alternative for patients unable to lie in prone position. The great intrinsic contrast between air or tagging and polyps allows the use of low radiation dose. Low-dose protocol without intravenous contrast should be used when extracolonic findings are deemed unimportant. In patients suspected for colorectal cancer, normal abdominal CT scan protocols and intravenous contrast should be used in supine position for the evaluation of extracolonic findings. Dose reduction can be obtained by lowering the tube current and/or voltage. Tube current modulation reduces the radiation dose (except in obese patients), and should be used when available. Iterative reconstructions is a promising dose reducing tool and dual-energy CT is currently evaluated for its applications in CT-colonography. This review also provides our institution's insufflation procedure and scan parameters.

Current techniques in the performance, interpretation, and reporting of CT colonography

The technical objective of computed tomographic colonography (CTC) is to acquire high-quality computed tomography images of the cleansed, well-distended colon for polyp detection. In this article the authors provide an overview of the technical components of CTC, from preparation of the patient to acquisition of the imaging data and basic methods of interpretation. In each section, the best evidence for current practices and recommendations is reviewed. Each of the technical components must be optimized to achieve high sensitivity in polyp detection.

Computed tomographic colonography

Computed tomographic colonography is a modern technique to evaluate the colon, which may be more appealing to patients than invasive methods. The potential of this test, including current and future developments are presented in this review. The essential steps required to perform a diagnostic quality computed tomographic colonography are discussed as well as different methods of study interpretation. The current status and promising areas of future investigation are also discussed.

Virtual Colonoscopy: Technique and Accuracy

Virtual colonoscopy (VC) has acquired an important role in evaluation of the colon. In some situations it may be a safer method to visualize the colon effectively, or it may be the only available option when other techniques have failed. This article reviews state-of-the art VC technique and the results of current performance trials. It discusses the rationale for using various colonic cleansing regimens for VC. It also discusses the two distending agents for VC (room air and carbon dioxide) and presents practical tips for administration and the role of antispasmodic drugs.

The emerging role of virtual colonoscopy

A review of the current status of virtual colonoscopy is germane and topical. Clinicians need to be knowledgeable about this rapidly evolving and clinically relevant technology to understand the test benefits and limitations and to refer patients for this test appropriately. A critical review of the exponentially expanding literature on this subject is important. This article describes the imaging meth-ods, adjunctive techniques, and radiologic interpretation of CT colonography, and comprehensively and critically reviews the clinical data to help the clinician evaluate the current and potential applications of this technology.

Efficacy of IV Buscopan as a muscle relaxant in CT colonography

The aim of this study was to examine the efficacy of IV Buscopan as a muscle relaxant in CT colonography in terms of colonic distension and polyp detection, and to determine its particular efficacy in patients with diverticular disease. Seventy-three consecutive patients were randomised to receive IV Buscopan or no muscle relaxant prior to CT colonography. CT colonography was performed using a Siemens Somatom 4-detector multislice CT scanner. The following parameters were recorded: degree of colonic distension using a 4-point scale; diagnostic adequacy of colonic distension; presence or absence of diverticular disease; and presence of colonic polyps. Accuracy of polyp detection was assessed using subsequent conventional colonoscopy as a gold standard. There was no significant difference between the two groups in the number of segments that were deemed to be optimally or adequately distended (p=0.37). Although IV Buscopan did improve distension of certain segments, this effect was not sufficient to improve the number of diagnostically adequate studies in the Buscopan group (p=0.14). In patients with diverticular disease, IV Buscopan did not have any significant effect on segments affected by diverticulosis but was associated with an improvement in distension of more proximal segments. There was no significant difference between the two groups in terms of polyp detection (p=0.34). The addition of prone scanning to supine scanning was found to be the most useful technique for maximising colonic distension. Intravenous Buscopan at CT colonography does not improve the overall adequacy of colonic distension nor the accuracy of polyp detection. In patients with sigmoid diverticular disease IV Buscopan improves distension of more proximal colonic segments and may be useful in selected cases, but our results do not support its routine use for CT colonography.

A double-blind randomised, placebo-controlled trial evaluating the influence of oral long-acting muscle relaxant (Mebeverine MR), and insufflation with CO(2) on pain associated with barium enema

Previous investigators have shown significant benefit using CO(2) for bowel insufflation. Others have suggested that the long-acting smooth muscle relaxant, Mebeverine, may be of benefit. We subjected this to a randomised double-blind trial. A total of 181 outpatients were randomised to receive either Mebeverine or placebo as pre-medication, and either air or CO(2) for bowel insufflation, thus creating four treatment groups. Visual-analogue lines were used to record pain scores before, during, and up to 8 h following the enema. All groups showed increased pain scores during the enema, with peak pain scores at the end of the examination, falling to baseline scores by 8 h. Patients receiving the combination of C0(2) and placebo had significantly lower pain scores at 1 and 4 h ( P=0.00 and P=0.014, respectively; Kruskal-Wallis test) compared with all other groups. Having Mebeverine as a pre-medication did not significantly lower pain scores compared with placebo, and decreased the amount of benefit received from the CO(2). We confirm that CO(2) is of benefit in decreasing pain during barium enema, and we recommend its routine use to improve the comfort of patients. Mebeverine is not of benefit, and its use as a pre-medication for enemas is not recommended.

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.

Ferristene as intestinal MR contrast agent. Distribution and safety of a fast ingestion procedure with oral metoclopramide

PURPOSE

To compare the small bowel distribution and safety of a fast ingestion procedure of ferristene to those of the standard ingestion procedure.

MATERIAL AND METHODS

Sixty-four patients received 0.5 g/l ferristene in 800 ml water. Thirty-four patients of the fast ingestion group ingested ferristene with 20 mg of oral metoclopramide during the course of 30 min before MR imaging and received an i.v. injection of an antiperistaltic agent during the MR study. Thirty patients of the standard group ingested ferristene during the course of 2 h, without additional drugs. Ferristene distribution was assessed by 2 reviewers and adverse events were recorded.

RESULTS

More than 50% of the small bowel segments analyzed were filled with ferristene in 30 patients in the fast ingestion group and in 28 patients in the standard ingestion group. One patient in each group experienced nausea and/or vomiting. Some bloating or sensation of fullness was reported by 2 patients in the fast ingestion group and by 3 patients in the standard ingestion group.

CONCLUSION

The distribution of ferristene in the small bowel and the safety of the procedure were thus similar in the 2 groups using either a fast ingestion procedure with oral metoclopramide or the more time-consuming standard ingestion procedure.

Increased muscle sympathetic nerve activity after glucagon administration in man

Muscle sympathetic nerve activity (MSNA) after glucagon administration was quantitatively measured in five healthy male volunteers (age: 20-28 years old). After an overnight fasting, 1 mg glucagon dissolved in a 1-ml vehicle was injected i.v. as a bolus. MSNA, ECG and blood pressure were simultaneously recorded 15 min before and after the injection. MSNA (bursts/min), heart rate (HR), and systolic and diastolic blood pressures (dBP and sBP) were significantly increased at 2-3 min after glucagon injection. Their means and standard deviations of control for 15 min vs. 3 min after the injection were in the five subjects; MSNA, 10 +/- 6 vs. 30 +/- 10 bursts/min, HR, 61 +/- 10 vs. 76 +/- 8 beats/min, dBP, 66 +/- 9 vs. 91 +/- 9 mmHg and sBP, 122 +/- 12 vs. 152 +/- 11 mmHg. These results suggest that glucagon has a direct facilitatory effect on the central sympathetic nervous system.

Use of antispasmodic drugs in double contrast barium enema examination: glucagon or buscopan?

PURPOSE

To compare the spasmolytic effect of glucagon and buscopan in double contrast barium enema examination.

PATIENTS AND METHODS

Three hundred and twenty-four consecutive patients referred for double contrast barium enema examination were randomly allocated to receive an intravenous injection of either 1 mg of glucagon, 20 mg of buscopan or physiological saline. The transit of the barium column from rectum to caecum, the quality of the radiographs and side effects were assessed blindly without knowledge of the injected drug.

RESULTS

Antispasmodic drugs (glucagon or buscopan) resulted in better transit of the barium column to the caecum compared to placebo (Mann-Whitney: P < 0.05), but no differences occurred between glucagon and buscopan (Mann-Whitney: P > 0.05). Buscopan produced better distension of the rectosigmoid than glucagon or placebo (P < 0.05). Of 109 patients who received buscopan five complained of blurred vision afterwards.

CONCLUSION

Because buscopan is less expensive and more effective in distending the colon than glucagon, it is preferred for the routine double contrast examination. However, patients should be warned about the possibility of temporary visual impairment.

A randomized study comparing glucagon and hyoscine N-butyl bromide before endoscopic retrograde cholangiopancreatography

BACKGROUND

This study tried to resolve whether glucagon is a better premedication for endoscopic retrograde cholangiopancreatography (ERCP).

METHODS

We first measured the basal blood sugar and amylase levels. Then an endoscope was placed in the duodenum without premedication, and basal pulse and duodenal peristaltic rates were measured. ERCP began after studied subjects were randomly premedicated with either 1 mg glucagon (n = 38) or 40 mg hyoscine N-butyl bromide (n = 36) intravenously. Ten minutes later the variables were measured again.

RESULTS

Glucagon elicited hyperglycemia whereas hyoscine N-butyl bromide manifested an anticholinergic effect. No difference was found between these two groups with regard to the necessary interval for ERCP (20.6 +/- 14.1 min versus 21.4 +/- 14.7 min; NS) or the success rate for cholangiopancreatography (92.1% versus 91.7%; NS). Neither hyperamylasemia nor pancreatitis was preventable when glucagon was used.

CONCLUSIONS

The two premedications appear equally effective in the performance of ERCP.

Buscopan and glaucoma: a survey of current practice

Hyoscine butylbromide (Buscopan) is commonly used by radiologists in the UK as a hypotonic agent in double-contract gastrointestinal studies. A history of glaucoma is still taught to be the prime contraindication to its use, although the only individuals at risk are those with undiagnosed and therefore untreated angle closure glaucoma (ACG), who will not give a positive history. We conducted a postal survey of all members and fellows of the Royal College of Radiologists in the UK to establish current practice.

RESULTS

Of the 1045 respondents who use Buscopan, 724 (81.6%) withhold it if the patient gives a history of glaucoma, and 631 (87.2%) of this group substitute glucagon. Of the 51 respondents who state that they understand that the patient who gives the positive history is not the one at risk, 22 continue to withhold Buscopan because of the established teaching. Only 429 (52.4%) substitute glucagon for Buscopan if the patient gives a history of heart disease. Eight respondents (0.8%) have seen an attack of glaucoma thought to have been precipitated by Buscopan, and 20 (1.9%) have seen cardiac complications.

CONCLUSION

There are still widespread misconceptions about the contraindications to the use of Buscopan among radiologists in the UK. We recommend abandoning the practice of enquiring about a history of glaucoma, and substituting advice to seek urgent medical advice should eye pain and visual loss develop. Caution in the patient with heart disease appears to be of greater importance.

Utility of glucagon in the emergency department

Glucagon is a pancreatic polypeptide hormone that has diverse utility as both a therapeutic and diagnostic agent. Many of its pharmacologic actions are pertinent to the practice of emergency medicine. The author reviews the literature supporting each potential use of the drug and the purported physiologic mechanisms by which glucagon exerts these actions. The indications and proper dosages for glucagon in the acute care setting are summarized.

Stenting in malignant vena caval obstruction

BACKGROUND

For patients with recurrent vascular obstruction of the vena cava due to tumor regrowth after chemotherapy or radiation therapy and occasionally surgery, no current therapy is available. With the development of intravascular stenting, a new option becomes available in the treatment of a vena caval syndrome.

METHODS

Twenty-two patients were treated for malignant obstruction of the vena cava by single, double, and triple Z-type metal stents. All patients had been pretreated extensively and their disease was not amenable to other therapeutic techniques at the time of stenting.

RESULTS

Correct positioning of the stents was achieved in all patients. In 68% of patients (n = 15), the symptoms completely disappeared without recurrence until death as a result of tumor progression. In 18% of patients (n = 4), a remarkable improvement was observed, but there was no complete disappearance of symptoms. In 14% of patients (n = 3), reocclusion of the vena cava occurred. The median survival time was 3.0 months (range, 1 week to 9 months).

CONCLUSIONS

The application of Z-type metal stents in patients with recurrent malignant obstruction of the vena cava appears to be a useful palliative procedure.

Strecker stent in stenotic hemodialysis Brescia-Cimino arteriovenous fistulas

Flexible tantalum stents (Strecker) were used as an adjunct to percutaneous transluminal angioplasty (PTA) in the treatment of stenotic arterial or venous limbs of Brescia-Cimino hemodialysis fistulas. The diagnostic procedure was performed using retrograde fistulography. After PTA with unsatisfactory results, stents were placed in 5 patients with significant residual stenoses and poor fistula function. Within the mean follow-up period of 6.4 months (range 3-10 months) all fistulas were functioning. We conclude that Strecker stent is useful in the treatment of stenotic hemodialysis arteriovenous fistulas as an adjunct to PTA.