Gadolinium Retention after Contrast-Enhanced Magnetic Resonance Imaging: A Narratative Review

Over the past five years, several studies have reported deposition and retention of gadolinium in the brain after administration of gadolinium-based contrast agents (GBCAs) during radiological procedures. Patients with renal insufficiency cannot filter gadolinium efficiently; however, gadolinium is also retained in the brain of some adults and pediatrics with no renal impairment. In the literature, data is mostly available from retrospective magnetic resonance imaging (MRI) studies, where gadolinium deposition may be indirectly measured by evaluating changes in T1 signal intensity in the brain tissues, particularly in the deep gray matter such as the dentate nucleus and/or globus pallidus. Many pathological studies have reported a direct correlation between T1 signal changes and gadolinium deposition in human and animal autopsy specimens, which raised concerns on the use of GBCAs, particularly with linear chelators. The association between gadolinium accumulation and occurrence of physical and neurological side effects or neurotoxic damage has not yet been conclusively demonstrated. Studies have also observed that gadolinium is deposited in the extracranial tissues, such as the liver, skin, and bone, of patients with normal kidney function. This narrative review describes the effects of different types of GBCAs in relation to gadolinium deposition, evaluates current evidence on gadolinium deposition in various tissues of the human body, and summarizes the current recommendations regarding the use of GBCAs.