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Abstract

We thank Singleton for her comments on the use of rapid brain magnetic resonance imaging (MRI) for the diagnosis of ventricular shunt malfunction in children. We agree that this modality has shown great promise for the diagnosis of shunt malfunction, and offers the advantage of avoiding potentially harmful radiation exposure associated with computed tomography (CT). In our study, which utilized the Pediatric Health Information System, we were unable to discern which hospitals had rapid MRI protocols. We observed that use of brain MRI remained low throughout the study period; however, there was an increase in its utilization during the final year of the study. The study by Yue et al cited by Singleton illustrates some of the trade-offs between MRI and CT. Although the sensitivities of MRI and CT were similar, MRI was often associated with a longer time to completion. Interestingly, a single-center study of 698 children with ventricular shunt observed that fewer children undergoing MRI required sedation compared with CT (0.6% vs 7%, respectively, P < .001).1Boyle T.P. Paldino M.J. Kimia A.A. Fitz B.M. Madsen J.R. Monuteaux M.C. et al.Comparison of rapid cranial MRI to CT for ventricular shunt malfunction.Pediatrics. 2014; 134: e47-e54Crossref PubMed Scopus (43) Google Scholar Similar to the Yue study, accuracy (82.4% [95% CI, 78, 86.1] for CT vs 81.8% [77.5, 85.4] for MRI) and specificity (86.4% [81.8, 90] for CT vs 89.0% [84.9, 92.1] for MRI) of MRI was not inferior to CT in this study, but it was underpowered to compare sensitivity. In addition, time to imaging, overall Emergency Department length of stay, and time to the operating room when indicated, was longer for children who received MRI compared with CT. As institutions become more facile with rapid MRI protocols, it is likely that cost, need for sedation, and time to neuroimaging will improve. Given the frequency of neuroimaging that children with ventricular shunts receive over the course of their lifetimes, the advantages of decreased ionizing radiation and potentially decreased need for sedation are substantial. Rapid brain magnetic resonance imaging: An alternative to head computed tomography for evaluation of ventricular shunt malfunctionThe Journal of PediatricsVol. 171PreviewI commend Florin et al on bringing attention to the variation of head computed tomography (CT) utilization in the evaluation of shunt malfunctions and the associated radiation exposure. The 1319 children in their study had 6636 emergency department visits over 10 years. Head CT was obtained in 49.4% of encounters.1 During the study period, some hospitals reporting to Pediatric Health Information System were shifting to the use of rapid magnetic resonance imaging (MRI).2 An important factor not considered was the number of institutions using rapid MRI protocols. Full-Text PDF