Sean E Strickler1, Kevin R Clark2. 1. Associate instructor for Emory University's medical imaging program in Atlanta, Georgia. He recently completed his graduate studies in radiologic science education from Midwestern State University in Wichita Falls, Texas. 2. Assistant professor and associate graduate program director with the School of Health Professions for The University of Texas MD Anderson Cancer Center in Houston. He serves as a member of the ASRT Foundation Research and Grants Advisory Panel and Radiologic Technology Editorial Review Board. He also is chair and delegate for the ASRT Education Chapter. KRClark@mdanderson.org.
Abstract
PURPOSE: To analyze literature specific to gadolinium deposition and inform medical imaging professionals about potential risks of contrast retention related to magnetic resonance (MR) imaging examinations as well as alternative imaging techniques that reduce or eliminate the need for gadolinium-based contrast agents (GBCAs). METHODS: Peer-reviewed journal articles were collected using PubMed, Academic Search Complete, and Science Direct electronic databases. Information from an MR textbook and reports from various organizations complemented the scholarly sources. RESULTS: The literature focused on classifications of GBCAs, associated risks, deposition rates, current recommendations, and alternative imaging techniques. DISCUSSION: Less stable nonionic linear agents accumulate in tissues at a higher rate than do ionic macrocyclic agents. Deposition still occurs with more stable macrocyclic agents but at lower levels. MR technologists are responsible for checking their patients' renal function and choosing the most appropriate GBCA while adhering to current recommendations regarding contrast administration. The clinical significance of retained gadolinium in the brain is unknown. Long-term studies are necessary to determine whether gadolinium deposition in the brain causes neurological deficits. Until those clinical implications are understood fully, discussions will continue about the use of alternative imaging techniques that reduce or eliminate the need for GBCAs. CONCLUSION: Decisions regarding patients at risk for gadolinium retention should be made on a case-by-case basis, with the risks and benefits weighed. Every effort should be made to minimize residual gadolinium, especially in patients who have renal insufficiency and in patients who require repeated contrast examinations. When contrast is necessary, MR technologists should use the most stable type in the lowest possible dose.
PURPOSE: To analyze literature specific to gadolinium deposition and inform medical imaging professionals about potential risks of contrast retention related to magnetic resonance (MR) imaging examinations as well as alternative imaging techniques that reduce or eliminate the need for gadolinium-based contrast agents (GBCAs). METHODS: Peer-reviewed journal articles were collected using PubMed, Academic Search Complete, and Science Direct electronic databases. Information from an MR textbook and reports from various organizations complemented the scholarly sources. RESULTS: The literature focused on classifications of GBCAs, associated risks, deposition rates, current recommendations, and alternative imaging techniques. DISCUSSION: Less stable nonionic linear agents accumulate in tissues at a higher rate than do ionic macrocyclic agents. Deposition still occurs with more stable macrocyclic agents but at lower levels. MR technologists are responsible for checking their patients' renal function and choosing the most appropriate GBCA while adhering to current recommendations regarding contrast administration. The clinical significance of retained gadolinium in the brain is unknown. Long-term studies are necessary to determine whether gadolinium deposition in the brain causes neurological deficits. Until those clinical implications are understood fully, discussions will continue about the use of alternative imaging techniques that reduce or eliminate the need for GBCAs. CONCLUSION: Decisions regarding patients at risk for gadolinium retention should be made on a case-by-case basis, with the risks and benefits weighed. Every effort should be made to minimize residual gadolinium, especially in patients who have renal insufficiency and in patients who require repeated contrast examinations. When contrast is necessary, MR technologists should use the most stable type in the lowest possible dose.