Prenatal diagnosis of complete vascular ring using high-definition flow render mode and spatiotemporal image correlation

Evaluating the efficacy of sequential cross-sectional scanning and combined teaching methods for prenatal screening of fetal conotruncal anomalies

OBJECTIVE

This study aimed to explore the effectiveness of combining fetal heart sequential cross-sectional scanning with drawing methods, mind mapping, and case-based learning (CBL) for training in fetal conotruncal anomalies (CA) screening.

METHOD

An experimental control method was employed. Doctors participating in continuing fetal ultrasound education were randomly divided into two groups. Both groups received theoretical instruction on fetal heart embryology, development, and abnormal arterial trunk development. Group A received traditional teaching methods for both theory and skills, with the skills course focusing on routine fetal heart scanning. Group B received a mixed teaching approach incorporating pathological mind mapping, CBL teaching, and drawing methods for both theory and skills courses. Group B's skills training focused on the sequential cross-sectional scanning method. The effectiveness of the training was evaluated by analyzing the classroom learning results and conducting a questionnaire survey of both groups.

RESULT

Group B participants achieved significantly higher scores on both theoretical and skills assessments compared to Group A. The diagnostic accuracy of different diseases in group B was significantly higher than that in group A, except for AVSD and APW. The post-class questionnaire revealed that participants in Group B expressed greater satisfaction with the combined teaching approach. They perceived a significant improvement in their independent learning abilities, diagnostic skills for related diseases, clinical skills, and overall competence compared to the traditional teaching group. The post-training correlation analysis did not identify any association between working years and theoretical or technical performance after training.

CONCLUSION

This study demonstrates that combining fetal heart sequential cross-sectional scanning with a variety of teaching methods, including drawing methods, mind mapping, and CBL, can enhance understanding of fetal trunk structure scanning and foster the development of clinical reasoning skills, ultimately leading to improved diagnostic accuracy in the identification and differential diagnosis of conotruncal anomalies.

Prenatal Diagnosis of Persistent Left Superior Vena Cava Using High-Definition Flow Render Mode and Spatiotemporal Image Correlation

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.

Evaluation of tracheal diameter and angles in fetuses with double aortic arch using prenatal ultrasound: implications for postnatal management

Objective

This study aims to analyze the value of prenatal ultrasound in the screening, diagnosis, and treatment of double aortic arch (DAA) malformations.

Methods

A retrospective analysis was conducted on 31 fetal cases with double aortic arch anomalies over a 12-year period from June 1, 2011 to June 1, 2023. The assessment included combined measurements of fetal tracheal internal diameter Z-score and DAA pinch angle, along with ultrasonographic findings, associated anomalies, genetic abnormalities, postnatal CTA images, and long-term postnatal outcomes.

Results

Of the 31 fetal double aortic arch cases, 15 were right aortic arch dominant, 2 were left aortic arch dominant, and 14 had a balanced double arch. Genetic testing was performed on 19 cases, revealing abnormalities in 2 cases, including one Turner syndrome, and one carrier of ichthyosis gene with heterozygous deletion. Out of the total cases, 29 were delivered, and 2 cases were terminated. Prenatal diagnosis accurately identified 29 cases (29/31, 93.5%), which was confirmed by postnatal pathological anatomy, echocardiography, surgery or CTA. Fetal tracheal internal diameter Z-scores were significantly smaller in the symptomatic group than in the asymptomatic group (-1.27 ± 0.49 vs -0.68 ± 0.60, P = 0.018). The area under the curve was 0.776 (95% confidence interval, 0.593-0.960) using a tracheal internal diameter z-score cutoff of -0.73 with a sensitivity of 90% and specificity of 64.7%. The double arch pinch angle was significantly smaller in the symptomatic group than in the asymptomatic group [52.50° (38.25° to 59.00°) vs 60.00° (53.50° to 70.50°), P = 0.035]. The area under the curve was 0.744 (95% confidence interval, 0.554-0.935), and the sensitivity for determining the presence or absence of symptoms was 90% when the cutoff value was 62.5°, with a specificity of 47.1%. Fifteen cases opted for surgery with favorable surgical outcome.

Conclusion

Prenatal echocardiography demonstrates good diagnostic efficacy for fetal double aortic arch. It is also essential to detect the presence of other underlying intra- and extracardiac malformations and genetic abnormalities. There is a significant difference in prenatal tracheal internal diameter Z-scores and double arch pinch angle between asymptomatic and symptomatic DAA infants. Symptomatic infants require early surgery, while asymptomatic infants should be monitored.

3D printing of foetal vascular rings: feasibility and applicability

BACKGROUND

Vascular rings (VRs) exhibit complex and diverse forms that are difficult to conceptualize using traditional two-dimensional (2D) schematic. Inexperienced medical students and parents who lack a medical technology background face significant challenges in understanding VRs. The purpose of this research is to develop three-dimensional (3D) printing models of VRs to provide new technical imaging support for medical education and parental consultation.

METHODS

This study included 42 fetuses diagnosed as VRs. Foetal echocardiography, modeling and 3D printing were performed, and the dimensional accuracy of models was analyzed. The value of 3D printing in the teaching of VRs was analyzed based on comparing the test results before and after the teaching intervention of 48 medical students and the satisfaction survey. A brief survey was conducted to 40 parents to assess the value of the 3D printed model in prenatal consultations.

RESULTS

Forty models of VRs were successfully obtained, which reproduced the anatomical shape of the VRs space with high dimensional accuracy. No differences in the prelecture test results were noted between the 3D printing group and the 2D image group. After the lecture, the knowledge of both groups improved, but the postlecture score and the change in the prelecture versus postlecture score were greater in the 3D printing group, and the subjective satisfaction survey feedback in the 3D printing group was also better (P < 0.05). Similar results were observed from the parental questionnaire, the vast majority of parents have an enthusiastic and positive attitude towards the use of 3D printed models and suggest using them in future prenatal consultations.

CONCLUSIONS

Three-dimensional printing technology providing a new tool for effectively displaying different types of foetal VRs. This tool helps physicians and families understand the complex structure of foetal great vessels, positively impacting medical instruction and prenatal counselling.

The telediagnosis of double aortic arch using spatio-temporal image correlation

We diagnosed two cases of double aortic arch (DAA) remotely. In both cases, the right aortic arch was suspected, and a remote diagnosis was requested. We performed a remote diagnosis by the spatio-temporal image correlation (STIC) method. DAA was diagnosed by detecting the left aortic arch in an axial transverse section in the three-vessel trachea view. Since the STIC method can make multiple cross sections, making a diagnosis by the STIC method was useful for the remote diagnosis of these patients. In particular, HD flow render mode clearly showed left aortic arch, so it was possible to diagnose DAA.