Scoping Review of the Prenatal Diagnosis of Agenesis of the Corpus Callosum

Abstract

Objective: To map and summarize the literature related to the prenatal diagnosis of agenesis of the corpus callosum (ACC) to inform nursing practice.

Data sources: We searched MEDLINE, CINAHL, PyscINFO, and Academic Search Complete with the use of strings of curated terms to cover the broad ACC nomenclature. Documents were published in English between 2009 and June 1, 2020. We also hand searched the reference lists of included documents.

Study selection: We screened 582 abstracts and retrieved the full texts of primary research articles, reviews, discussion papers, and peer-reviewed book chapters if the abstracts specifically mentioned ACC and the prenatal period. We excluded case reports, conference and poster abstracts, papers on broader anomalies, and animal studies. We reviewed 84 full-text documents and identified 61 for inclusion.

Data extraction: We charted the data through an iterative process under headings for location, article type, study design, participant age, ACC type, recruitment, method, tools/assessments, results, key recommendations, gestational age at diagnosis, termination of pregnancy rate, the definition of isolated ACC, and our notes of critique of the document.

Data synthesis: We constructed a narrative synthesis from thematically arranged data. In the included documents, ACC was diagnosed between 17 and 38 weeks gestation and was frequently described as heterogeneous because of different causes, presentations, and outcomes. Whether the ACC was isolated as the only anomaly or present with other anomalies was considered the key factor for prenatal counseling. However, the definition of isolated ACC was inconsistent.

Conclusion: The inconsistent nomenclature and definitions of an isolated presentation of ACC increase the ambiguity in the prenatal diagnosis and must be considered when the outcome and diagnostic efficacy studies are interpreted. There is an absence of research on parents' experiences of prenatal diagnoses of ACC to inform holistic nursing interventions and the provision of psychosocial support.

Keywords: agenesis of corpus callosum; congenital abnormalities; midwifery; nursing; prenatal diagnosis; scoping review.