Contemporary strategies for dose optimization in pediatric congenital heart disease CT: size-specific acquisition and detector-level advances.

Pediatric patients, particularly those with congenital heart disease (CHD), are more radiosensitive than adults and frequently undergo repeated computed tomography (CT) examinations, making cumulative radiation exposure a major concern in cardiothoracic imaging. This special report provides a narrative, practice-oriented synthesis of contemporary strategies for dose optimization in pediatric CHD CT, organized into three mutually reinforcing layers. (1) Policy/audit: age- and size-stratified diagnostic reference levels (DRLs) and size-specific dose estimates (SSDE) are used to track median and 75th-percentile computed tomography dose index volume (CTDIvol) and dose-length product (DLP) values and to identify outliers that trigger protocol review. (2) Scanner/protocol: dose-efficient acquisition is achieved through low tube voltage (typically 70–80 kVp), automatic tube current/voltage modulation, prospectively electrocardiogram-triggered or high-pitch cardiac CT, tighter z-axis coverage and collimation, and advanced reconstruction (iterative and deep-learning methods). Wide-area (256–320-row) volume CT can further reduce overscanning, and emerging photon-counting detector CT may improve dose efficiency at very low mAs. (3) Workflow/education: standardized pediatric CT checklists (scout direction, table height/isocenter correction, electrocardiogram mode, and z-range) and automated per-examination logging of CTDIvol, DLP, SSDE, scan length, and positioning error enable a closed audit-and-feedback cycle consistent with end-to-end as low as reasonably achievable (ALARA) practice. Across these domains, the literature indicates that sub-mGy or near-sub-mGy cardiothoracic CT in small children is achievable when measures are implemented in combination rather than in isolation. Accordingly, this report proposes harmonized framework that institutions can adopt to reduce interfacility variability, align with evolving DRLs, and sustain safe, reproducible, and diagnostically adequate pediatric CHD CT imaging.