How to apply the DAZE technique: structured approach to fetal cardiac image optimization.

Accurate prenatal detection of congenital heart disease continues to be challenging in routine obstetric practice, despite established screening guidelines. Missed diagnoses are frequently associated with suboptimal image acquisition and inconsistent application of fundamental ultrasound optimization principles. High-quality fetal cardiac assessment requires intentional optimization of technical parameters, in addition to acquiring the recommended anatomical views. We describe, in the context of fetal cardiac imaging, the 'DAZE' (Depth, Angle, Zoom, Enhancement) technique, an organized and reproducible approach for systematically optimizing two-dimensional ultrasound imaging and the application of color Doppler. The DAZE technique consists of four sequential steps: 'D', adjustment of Depth and focal-zone placement; 'A', optimization of sector Angle width and Angle of insonation; Z, appropriate Zoom magnification; and E, Enhancement of ultrasound system settings. Practical application of each component is described, with an emphasis on optimizing spatial and temporal resolution on two-dimensional grayscale imaging, as well as optimizing the application of color Doppler. © 2026 International Society of Ultrasound in Obstetrics and Gynecology.