RESUMO
OBJECTIVE: This study aimed to assess the use of two-dimensional (2D) ultrasound combined with high-definition flow (HD-flow) render mode and spatiotemporal image correlation (STIC) in diagnosing and classifying fetal persistent left superior vena cava (PLSVC). METHODS: Overall, 114 cases of fetal PLSVC were diagnosed using 2D ultrasound combined with STIC, and 114 normal fetuses of the same gestational week were selected. These cases were retrospectively analyzed to evaluate the effectiveness of the diagnostic approach. RESULTS: All 114 PLSVC cases were diagnosed using 2D ultrasound combined with STIC. Although the diagnostic coincidence rate of PLSVC in the HD-flow combined with STIC was similar to that in the 2D ultrasound combined with HD-flow (96.8 vs 96.2%), 2D ultrasound with STIC enabled dynamic visualization of the PLSVC, furthering prenatal diagnosis. These cases were classified as type I PLSVC: 80 cases of type Ia, 29 cases of type Ib, and 5 cases of type Ic. Seventy isolated PLSVC cases (61.4%) were noted, whereas 44 cases (35.6%) were associated with concomitant structural abnormalities. Intracardiac structural malformations accounted for the highest proportion (n = 53, 58.89%), followed by single umbilical artery and facial/bodily abnormalities (n = 10, 11.11%). CONCLUSION: Combining HD-flow and STIC complements 2D ultrasound in diagnosing and classifying fetal PLSVC, demonstrating significant clinical relevance.