Diagnostic quality in endoscopic retrograde cholangiopancreatography: comparison between lodixanol and lopromide

Comparison of allergic adverse effects and contrast enhancement between iodixanol and iopromide

Background

Iodinated X-ray contrast media are the most commonly used contrast agents in the world with an annual application of 40-50 million. New non-ionic contrast agents are subdivided into low osmolar agents such as iopromide and iso-osmolar agents such as iodixanol. Regarding different biochemical characteristics, these agents are different in the allergic reactions and contrast enhancement and final lesion conspicuity.

Objectives

This study was carried out to compare allergic adverse effects and contrast enhancement between iodixanol and iopromide.

Patients and Methods

One-hundred and twenty patients who were referred for abdominal CT scan to Besat Hospital were included in this study. Patients were randomly divided into two groups (A and B). Group A received 100 cc iodixanol (300 mgI/mL) and group B received 100 cc iopromide (300 mgI/ml) by power injector. CT examination was performed using Helical CT Scanner (Somatom, Siemens, Germany). Sixty seconds after injection, images were obtained and enhancement of port, liver and aorta were determined. Allergic adverse effects were recorded one hour and up to one week after injection.

Results

Iodixanol produced a significantly greater enhancement of the hepatic, aorta and portal vein than iopromide (P < 0.01). Sixty seconds after injection, associated pain and heat sensation were less frequent in iodixanol in comparison with iopromide (P = 0.03). Immediate reactions such as nausea and vomiting were less frequent in iodixanol (P = 0.01). Late skin reactions such as rash was more frequent in iodixanol (P < 0.01).

Conclusions

Iodixanol is safe and is better tolerated in the early phase of injection with better contrast enhancement and lesion conspicuity. Mild late skin rash is its disadvantage.

Effects of contrast media on the hepato-pancreato-biliary system

AIM: To determine the effects of high osmolarity contrast media (HOCM) and iso-osmolar contrast media (CM) application, with or without pressure, on hepato-pancreato-biliary (HPB) system.

METHODS: Sixty rats were divided into six equal groups as follows: Group 1: (0.9% NaCl, control), Group 2: (diatrizoate meglumine Na, ionic HOCM, Urographin^®), Group 3: (iodixanol, iso-osmolar non-ionic CM, Visipaque^®); each of which was applied without pressure, whereas the animals of the remaining three groups (1p, 2p, 3p) were subjected to the same CM with pressure. We performed a duodenal puncture and introduced a catheter into the ampulla. After the catheterization, 0.2 mL CM or 0.9% NaCl was injected with or without pressure. Blood samples were taken for biochemical evaluations. The histopathological examinations of liver, common bile duct, and pancreas were performed.

RESULTS: There were no significant differences between the six groups for blood amylase, alanine aminotransferases, aspartate aminotransferases, bilirubin levels (P > 0.05). Alkaline phosphatase and γ glutamyl transaminase levels were higher (P < 0.05) in the Urographin^® groups (2, 2p) than the Visipaque^® groups (3, 3p), or control groups (1, 1p). Hepatocyte necrosis, portal area inflammation, and Kupffer’s cell hyperplasia were higher (P < 0.05) in the study groups than the control group. However, there were no significant differences (P > 0.05) between HOCM (2, 2p) and iso-osmolar CM (3, 3p) groups. Bile duct proliferation and regeneration in the Urographin^® groups (2, 2p) were significantly higher (P < 0.05) than the Visipaque^® groups (3, 3p) or the control groups (1, 1p). Although CM caused minor damage to the pancreas, there were no statistically significant differences (P > 0.05) between the groups. Application of the CM with pressure did not cause additional damage to the HPB system.

CONCLUSION: Iso-osmolar, non-ionic CM could be more reliable than the ionic HOCM, whereas the application of pressure during the CM application had no effect on the HPB system.

Role of osmolality of contrast media in the development of post-ERCP pancreatitis: a metanalysis

The role of osmolality of contrast media (CM) in the development of post-ERCP pancreatitis (PEP) is debated. We therefore performed a metanalysis to determine whether osmolality affects the incidence of PEP. A literature search of English-language studies was performed using computerized databases and manual searching of abstracts and article bibliographies. Randomized controlled trials comparing the incidence of PEP associated with high- and low-osmolality contrast media (HOCM, LOCM) were considered. The outcome assessed was clinical pancreatitis as evidenced by both elevation of pancreatic enzymes and pain. Data were analyzed using logistic regression with terms for study and osmolality. Fisher's exact test was done to compare PEP rates. Homogeneity between studies was indicated by the nonsignificance of the study effect in the logistic regression model. Logistic regression also indicated no difference in PEP rates between LOCM and HOCM (P = 0.399). Comparison of PEP rates in both groups using Fisher's exact test did not indicate a difference in any individual study (all P values > 0.05). Due to the large variation of study sample sizes, we repeated the analysis by creating three study groups. The effect of osmolality was invariant to how the data were combined. The results of this metanalysis indicate that there is no significant difference between HOCM and LOCM with respect to clinical PEP.