IV Glucagon Use in Pediatric MR Enterography: Effect on Image Quality, Length of Examination, and Patient Tolerance

Abstract

The objective of our study was to evaluate the use of i.v. glucagon in pediatric patients undergoing MR enterography. Forty-seven patients underwent clinical MR enterography examinations consisting of identical breath-hold T1-weighted 3D gradient-recalled echo fat-saturated pulse sequences before and after i.v. glucagon administration. Images were reviewed in a blinded manner by two pediatric radiologists to determine the effect of glucagon on visualization of the small and large bowel. Image time stamps were documented separately to determine how this adjunctive medication affected examination length. A separate cohort of 50 patients was evaluated for glucagon-related symptoms, including nausea and emesis. Exact binomial testing was performed to establish whether overall visualization of the bowel and visualization of the terminal ileum were better on images with i.v. glucagon. The two-tailed Wilcoxon signed rank test was used to compare Likertlike scores for bowel visualization before and after i.v. glucagon administration. Glucagon improved overall bowel visualization in 40 of 47 (85%) examinations for reader 1 (p < 0.0001) and 36 of 47 (77%) for reader 2 (p = 0.0001). Visualization of the terminal ileum was improved after glucagon administration in 29 of 47 (62%) examinations for both readers (p = 0.03). Glucagon improved visualization of the small bowel for reader 1 (mean score on 5-point Likertlike scale: 3.3 ± 1.0 [SD] vs 2.2 ± 0.7, respectively; p < 0.0001) and reader 2 (3.4 ± 1.1 vs 2.5 ± 0.9; p < 0.0001). Glucagon also improved large-bowel visualization for reader 1 (3.3 ± 0.9 vs 3.0 ± 0.8; p = 0.005) and reader 2 (3.4 ± 1.1 vs 3.0 ± 1.0; p = 0.002). On average, the use of glucagon added 13.7 minutes to the examination. Twenty-four of 50 (48%) patients self-reported glucagon-related nausea and four patients experienced emesis. I.v. glucagon improves bowel visualization at pediatric MR enterography, increases examination length, and commonly causes nausea. Fewer than 10% of patients experience glucagon-related emesis in our practice.