Importance: Incidental findings (IFs) are unexpected abnormalities discovered during imaging and can range from normal anatomic variants to findings requiring urgent medical intervention. In the case of brain magnetic resonance imaging (MRI), reliable data about the prevalence and significance of IFs in the general population are limited, making it difficult to anticipate, communicate, and manage these findings. Objectives: To determine the overall prevalence of IFs in brain MRI in the nonclinical pediatric population as well as the rates of specific findings and findings for which clinical referral is recommended. Design, Setting, and Participants: This cohort study was based on the April 2019 release of baseline data from 11810 children aged 9 to 10 years who were enrolled and completed baseline neuroimaging in the Adolescent Brain Cognitive Development (ABCD) study, the largest US population-based longitudinal observational study of brain development and child health, between September 1, 2016, and November 15, 2018. Participants were enrolled at 21 sites across the US designed to mirror the demographic characteristics of the US population. Baseline structural MRIs were centrally reviewed for IFs by board-certified neuroradiologists and findings were described and categorized (category 1, no abnormal findings; 2, no referral recommended; 3; consider referral; and 4, consider immediate referral). Children were enrolled through a broad school-based recruitment process in which all children of eligible age at selected schools were invited to participate. Exclusion criteria were severe sensory, intellectual, medical, or neurologic disorders that would preclude or interfere with study participation. During the enrollment process, demographic data were monitored to ensure that the study met targets for sex, socioeconomic, ethnic, and racial diversity. Data were analyzed from March 15, 2018, to November 20, 2020. Main Outcomes and Measures: Percentage of children with IFs in each category and prevalence of specific IFs. Results: A total of 11679 children (52.1% boys, mean [SD] age, 9.9 [0.62] years) had interpretable baseline structural MRI results. Of these, 2464 participants (21.1%) had IFs, including 2013 children (17.2%) assigned to category 2, 431 (3.7%) assigned to category 3, and 20 (0.2%) assigned to category 4. Overall rates of IFs did not differ significantly between singleton and twin gestations or between monozygotic and dizygotic twins, but heritability analysis showed heritability for the presence or absence of IFs (h2= 0.260; 95% CI, 0.135-0.387). Conclusions and Relevance: Incidental findings in brain MRI and findings with potential clinical significance are both common in the general pediatric population. By assessing IFs and concurrent developmental and health measures and following these findings over the longitudinal study course, the ABCD study has the potential to determine the significance of many common IFs.
Bibliographical noteFunding Information:
this article were obtained from the ABCD study (https://abcdstudy.org), held in the National Institute of Mental Health Data Archive. This is a multisite, longitudinal study designed to recruit more than 10 000 children age 9-10 years and follow up with them over 10 years into early adulthood. The ABCD study is supported by the National Institutes of Health and additional federal partners under award numbers U01DA041022, U01DA041028, U01DA041048, U01DA041089, U01DA041106, U01DA041118, U01DA041120, U01DA041134, U01DA041148, U01DA041156, U01DA041184, U24DA041123, U24DA041148, U01DA041093, and U01DA041025. A full list of supporters is available at https://abcdstudy.org/ federal-partners.html.
grants from the National Institutes of Health (NIH) with provided salary support during the conduct of the study and grants from the Radiologic Society for unrelated research. Dr Jernigan reported grants from National Institutes of Health during the conduct of the study. Dr Dale reported grants from National Institutes of Health Grant # U24DA041123 during the conduct of the study; in addition, Dr Dale had a patent for US7324842 licensed to Siemens Healthineers, a patent for US8107695 licensed to General Electric, a patent for US9568580B2 licensed to General Electric, and a patent for US20120280686 licensed to General Electric; and Dr Dale is a Founder of and holds equity in CorTechs Labs, Inc, and serves on its Scientific Advisory Board. He is also a member of the Scientific Advisory Board of Human Longevity Inc and receives funding through a research agreement with General Electric Healthcare. The terms of these arrangements have been reviewed and approved by the University of California, San Diego, in accordance with its conflict of interest policies. Dr Sugrue reported receiving grant U24DA041123 for the NIH during the conduct of the study. Dr Barch reported grants from National Institute of Drug Abuse and grants from National Institute of Mental Health during the conduct of the study. Dr Hagler reported a patent for EP-2141506-B1 licensed to GE HealthCare (non-exclusive royalty-free). Dr Sher's participation in the ABCD-12 USA project is funded, in part, by a consulting agreement with Washington University, grants from the NIH, various research grants, and a training grant awarded to the home institution as principal investigator or coinvestigator. Dr Heeringa reported grants from NIDA Prime: University of California, San Diego, during the conduct of the study. Dr Bjork reported grants from NIH/NIDA during the conduct of the study. Dr Zucker reported grants from NIH/ NIDA during the conduct of the study. Dr Neale reported grants from NIDA Without the grant the data would not have been collected during the conduct of the study. Dr Herting reported grants from University of Southern California during the conduct of the study. Dr Reeves reported grants from NIH during the conduct of the study. Dr Cloak reported grants from National Institutes of Health during the conduct of the study; grants from National Institute of Justice outside the submitted work. Dr Gonzalez reported grants from National Institutes of Health during the conduct of the study. Dr Karcher reported grants from National Institutes of Mental Health during the conduct of the study. Dr Paulus reported personal fees from UpToDate royalties for an article about methamphetamine outside the submitted work. Dr Gray reported other from Pfizer, Inc. Consultation outside the submitted work. Dr Weiss reported other from General Electric own stock; less than $10 000 outside the submitted work. Dr Nagel reported grants from NIH during the conduct of the study. Dr Bookheimer reported grants from UCLA during the conduct of the study. Dr Hewitt reported grants from the NIH during the conduct of the study. Dr Chang reported grants from the NIH during the conduct of the study. Dr Edwards reported grants from the NIH during the conduct of the study. Dr Iacono reported grants from the NIH during the conduct of the study. Dr Luciana reported grants from the NIH during the conduct of the study. Dr Clark reported grants from the NIDA during the conduct of the study. Dr Schirda reported grants from the NIH during the conduct of the study. Dr Lisdahl reported grants from the NIH during the conduct of the study. Dr Dosenbach reported grants from NIH NS088590, MH096773, MH124567, MH122066, MH121276 during the conduct of the study; other from NOUS Imaging outside the submitted work. No other disclosures were reported.
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