Purpose To introduce the cranial-dorsal-hip angle (angle CDH) as a novel quantitative tool for assessing fetal position in the first trimester and to validate its feasibility for future AI applications. Materials and Methods 2520 first-trimester fetal NT exams with 2582 CRL images (January-August 2022) were analyzed at a tertiary hospital as the pilot group. Additionally, 1418 cases with 1450 fetal CRL images (September-December 2022) were examined for validation. Three expert sonographers defined a standard for fetal positions. angle CDH measurements, conducted by two ultrasound technicians, were validated for consistency using Bland-Altman plots and the intra-class correlation coefficient (ICC). This method allowed for categorizing fetal positions as hyperflexion, neutral, and hyperextension based on angle CDH. Comparative accuracy was assessed against Ioannou, Wanyonyi, and Roux methods using the weighted Kappa coefficient (k value). Results The pilot group comprised 2186 fetal CRL images, and the validation group included 1193 images. Measurement consistency was high (ICCs of 0.993; P<0.001). The established 95% reference range for angle CDH in the neutral fetal position was 118.3 degrees to 137.8 degrees. The angle CDH method demonstrated superior accuracy over the Ioannou, Wanyonyi, and Roux methods in both groups, with accuracy rates of 94.5% (k values: 0.874, 95%CI: 0.852-0.896) in the pilot group, and 92.6% (k values: 0.838, 95%CI: 0.806-0.871) in the validation group. Conclusion The angle CDH method has been validated as a highly reproducible and accurate technique for first-trimester fetal position assessment. This sets the stage for its potential future integration into intelligent assessment models.

Objective:To determine the variation of cerebellar fissure with gestational weeks in normal fetuses and to establish the numeric reference range for fetal cerebellar fissure at 16-32 weeks.Methods:From June 2019 to December 2020, 644 singleton fetuses with no structural abnormalities diagnosed by prenatal ultrasound were selected as study subjects at Shenzhen Maternal and Child Health Hospital, and divided into two groups: fetuses at 12-15 weeks of gestation and those at 16-32 weeks. The primary fissure and horizontal fissure in two-dimensional images were observed, the number of cerebellar fissures at 16 to 32 weeks of gestation counted, and the morphological changes analyzed. Forty fetuses were randomly sampled and tested for repeatability between two observers. The normal numeric reference range for cerebellar fissure between 16 and 32 weeks of gestation was established. The correlation between the number of cerebellar fissures and gestational age was analyzed by Spearman correlation, and fitting equations were then established.Results:There was no significant difference in the repeatability test between the two observers. The scatter plots showed that the number of cerebellar fissures were positively correlated with gestational age (r=0.863, 0.698, 0.831, and 0.932, P＜0.001). Quadratic polynomial regression equations were each fitted to the models. The regression equations for the number of cerebellar fissures in three different regions and the total number of fissures were Y=0.974X-0.014X2 -12.65, Y=0.362X-0.005X2 -4.843, Y=-0.125X+0.006X2+0.285, and Y=1.800X-0.024X2 -22.904, respectively.Conclusion:Prenatal ultrasound can be used to observe and evaluate the development of fetal cerebellar fissures. The numeric reference range and morphological changes of the normal fetal cerebellar fissures may be useful for prenatal evaluation of the development of the cerebellar cortex.

Objective:To develop an artificial intelligence (AI) quality control model of fetal heart in the first trimester and verify its effectiveness.Methods:A total of 18 694 images of the four-chamber view(4CV) and three-vessel and tracheal view(3VT) of fetal heart in the first trimester were selected from Shenzhen Maternal and Child Health Hospital Affiliated to Southern Medical University since January 2022 to December 2022. A total of 14 432 images were manually annotated. The one-stage target detection algorithm YOLO V5 was used to train the AI quality control model in the first trimester of fetal heart, and 4 262 images (golden standard set by expert group) were used to evaluate the application effectiveness of AI quality control model. Kappa consistency test was used to compare the results of section classification and standard degree judgment from AI quality control model, Doctor 1(D1) and Doctor 2(D2).Results:①Precision of the AI quality control model was 0.895, recall was 0.852, mean average precision (mAP 50) was 0.873.The average precision(AP) of the AI quality control model for section classification was 0.907 (4CV) and 0.989 (3VT), respectively. ②Compared with the gold standard, the overall coincidence rate and consistency of section classification of AI quality control model, D1 and D2 were 99.91% (Kappa=0.998), 100% (Kappa=1.000), 100% (Kappa=1.000), respectively. The coincidence rate and consistency of the plane standard degree evaluation from the AI quality control model, D1 and D2 were 97.46% (Weighted Kappa=0.932), 93.73% (Weighted Kappa=0.847), and 93.12% (Weighted Kappa=0.832), respectively. Strong consistency was displayed. Moreover, AI quality control model showed the highest coincidence rate and the strongest consistency in judging section standard degree, which was superior to manual quality control. The time-consuming of AI quality control (0.012 s/sheet) was significantly less than the way of manual quality control (4.76-6.11 s/sheet)( Z=-8.079, P<0.001). Conclusions:The use of artificial intelligent fetal heart quality control model in the first trimester can effectively and accurately control the image quality.

Objective:To explore the effectiveness of artificial intelligent (AI) quality control system on the standard mid-sagittal view of fetal face in 11-13 +6 weeks of gestation. Methods:The quality of the images was evaluated using online " Intelligent ultrasonic quality control system" for 1 063 sections of fetal Nuchal translucency ultrasound images in the Ultrasound Department of Shenzhen Maternity and Child Healthcare Hospital of Southern Medical University. The manual quality control results and time consuming of two experts were compared with AI. The gold standard was decided by experts group with higher seniority.Results:The overall standard rate, substandard rate and nonstandard rate of the image evaluated by the intelligent quality control system was 87.3%, 2.82%, and 9.88%. The overall accuracy of images was 96.6%. The coincidence rates between AI and the two experts were 96.1% and 96.3%, respectively, with strong consistency (Kappa were 0.835 and 0.845 respectively). The time required for intelligent quality control was significantly shorter than manual quality control (208 s vs 6 696 s/6 602 s). All the differences were statistically significant ( Z=-3.981, P<0.001). Conclusions:The intelligent quality control system could accurately and quickly evaluate whether the mid-sagittal view of fetal face in 11-13 +6 weeks of gestation is standard.

目的 观察产科超声图像智能质量控制系统(IU QCS)的效能.方法 以IU QCS评价64家深圳医院573名医师采集的164010幅6774胎孕中晚期胎儿声像图的质量,由2名专家(E1/E2)对其中57444幅单幅图像进行质控;对比其对切面分类及标准程度的质控效能和一致性及耗时差异.结果 IU QCS质控总体标准率为81.16％,基本标准率10.10％,非标准率8.74％.IU QCS与E1/E2质控切面分类总体符合率分别为97.61％(56071/57444)及97.65％(56092/57444),一致性强(Kappa均>0.933);标准程度评价总体符合率为89.72％(50307/56071)及89.67％(50300/56092),一致性较强(Kappa均=0.658).IUQCS每100幅质控耗时明显小于人工质控[33(29,37)s vs.705(680,730)s vs.720(696,751)s,Z均=-20.776,P均<0.001].结论 利用产科IUQCS可较为准确、高效地实现图像质控.

Objective:To evaluate the clinical value of prenatal three-dimensional (3D) inversion imaging of the sylvian fissure, parietal occipital sulcus, and calcarine sulcus.Methods:The sylvian fissure, parietal occipital sulcus, and calcarine sulcus were assessed prospectively by 3D ultrasound (3D-US) inversion imaging and two-dimensional ultrasound (2D-US) in 133 fetuses with no structural abnormalities between 19 and 36+6 weeks of gestation at Shenzhen Maternity and Child Healthcare Hospital from June 2019 to July 2020. The examinations were divided into six groups according to gestational age. For each group, these sulci were assessed as absent or present. The changes of these 3D sulci imaging were observed in different groups. Thirty fetuses were randomly selected for intra- and inter-observer reproducibility testing by pearson chi-square test.Results:Along with the increase of the gestation age in different groups, the rates of 2D and 3D examinations to display the structures both became higher and higher. 2D-US and 3D-US showed 100% of sylvian fissure, parietal occipital sulcus, and calcarine sulcus at 22, 23, and 24~36 weeks, respectively. The display rate had no statistical difference between 2D-US and 3D inverted ultrasound in the six groups (P＞0.05). However, 3D inversion ultrasound was more vivid and intuitive than 2D-US. No significant intra- and inter-observer variability was found.Conclusion:3D inversion imaging can be used to better observe the morphological and spatial changes of the sylvian fissure, parietal occipital sulcus, and calcarine sulcus during middle and late pregnancy, which is an intuitive supplementary means for prenatal evaluation of cerebral cortex development and provides a new idea for future teaching and research of cerebral cortex development.

Objective:To assess the clinical value of online artificial intelligent quality control system in assessing obstetric ultrasound images.Methods:A total of 374 191 images of 15 640 obstetric ultrasound cases from 998 doctors in 137 hospitals in Shenzhen and Chongqing were selected from January 1 to June 30, 2021, and the quality of the images was evaluated using online artificial intelligent quality control system. Based on each image quality assessment result, the proportion of different standard levels of all planes was calculated. The appeal results were also recorded to observe the accuracy of the system. To survey the efficiency of the system, paired sample t test was used to compare the time spent by intelligent quality control and manual quality control.Results:The overall standard rate, substandard rate, and nonstandard rate were 81.18%, 12.06%, and 6.76%, respectively. A total of 285 appealed images (0.076%) were reviewed by authoritative experts, who confirmed the initial diagnosis in 126 images (44.21%), and did not support the initial diagnosis in 159 images (55.79%); the accuracy of the system reached 99.96% (374 032/374 191). The average time spent by intelligent quality control for 100 images was (32.7±5.1) s, significantly shorter than that spent by manual quality control by two ultrasound physicians [(705.3±37.2) s and (724.6±40.4) s, t=62.667 and 56.396, respectively, P＜0.001].Conclusion:The intelligent quality control system of obstetric ultrasound images allows the quality control to be performed objectively, accurately, and efficiently, which is of great significance to guide the improvement of image quality.

Objective:To explore the prenatal ultrasound features of fetal unilateral cerebellar hypoplasia.Methods:The prenatal ultrasonograms of six fetuses at Shenzhen Maternity and Child Healthcare Hospital Affiliated to Nanfang Medical University, who were diagnosed as having unilateral cerebellar hypoplasia were retrospectively reviewed. The prenatal ultrasound characteristics were summarized, and compared with the features of magnetic resonance imaging (MRI), postnatal ultrasound, and autopsy examinations. A literature review of prenatal diagnosis of such abnormality was performed.Results:The prenatal ultrasonograms of the six cases of unilateral cerebellar hypoplasia were characterized as asymmetry of the cerebellar hemispheres and/or a decrease in the transverse cerebellar diameter, with or without deformity of the cerebellar vermis. The cerebellum volume of the affected side decreased, along with an abnormal morphology, while the contralateral side was normal. Three cases had irregular borders in the affected side. After birth, one of the six fetuses was followed to one year old without neurological symptoms. Based on the prenatal and postnatal examination results of the six cases in the present study and those of 36 cases reported in the literature, it was found that cases with isolated unilateral cerebellar hypoplasia and those without intracranial abnormalities or other adverse pregnancy history like prenatal growth restriction or premature birth had better short-term prognosis than unilateral cerebellar hypoplasia fetuses with intracranial abnormalities.Conclusion:Unilateral cerebellar hypoplasia can be prenatally diagnosed based on the characteristic ultrasonic features and MRI can be used for differential diagnosis.

目的 探讨人工智能(artificial intelligence,AI)质量控制系统在提高胎儿上腹部水平横切面超声图像标准率中的应用价值.方法 应用"产前超声AI智慧云平台"对深圳市60家医院三个季度在产科超声检查中存储的胎儿上腹部水平横切面图像共18114张进行智能质控,受质控医生通过查阅质控结果及图像存在的不足之处针对性地加以改进.应用χ2检验对三个季度图像的标准率、不足原因及申诉情况进行两两比较,评估智能质控对于提高胎儿上腹部水平横切面标准程度的价值.结果 各医院第一、二、三季度胎儿上腹部水平横切面图像标准率分别为80.15％(5649/7048)、86.2％(4391/5096)、90.55％(5406/5970),各季度图像标准率逐步提高,两两比较差异有统计学意义(P<0.01);每个季度的不标准图像中,图像不足的主要原因是切面中出现了大片肺脏,分别为8.9％(631/7048)、7.0％(358/5096)、4.9％(294/5970),其次是脐静脉和门静脉汇合部显示不清,分别为4.3％(305/7048)、3.5％(181/5096)、2.6％(155/5970),这两类图像均显著减少,两两季度比较差异有统计学意义(P<0.01);医生申诉后维持智能评价结果的图像分别为66.4％(79/119)、49％(25/51)、33.3％(10/30),两两比较差异有统计学意义(P<0.01),提示各季度医生对图像认识错误率逐渐降低.结论 人工智能质量控制可有效提高胎儿上腹部水平横切面超声图像的标准率,提升医生对标准切面的认识.

This study was aimed at evaluating the performance of the innovative technique Smart Fetus (SF) developed to recognize the planes and obtain the basic biometric measurements of fetuses automatically. This prospective study included 1005 uncomplicated singleton pregnancies undergoing routine examinations. For every pregnancy, planes, including the transverse section of the thalami, transverse section of the abdomen and longitudinal section of the femur, were acquired, and standard biometric measurements, including biparietal diameter, head circumference, abdominal circumference and femur length, were obtained using SF and traditional ultrasound technique (TUT). The accuracy, reproducibility and time required for the analysis of SF were compared with those of TUT. In 998 of 1005 cases (99.30%), SF successfully acquired the sections and made all measurements. The agreement between the techniques was high for all measurements. The time to obtain sections and measure biometric parameters or solely measure biometric parameters was significantly shorter with SF than with TUT. No significant differences were found in SF repeated measurements obtained by two independent observers. The SF technique helped in the acquisition of reliable standard sections and biometric measurements and saved time. It might serve as a novel ultrasound scanning approach and improve workflow efficiency.

目的探讨新型智能产前超声技术（SF）技术包括标准切面自动识别与获取（SFDA）技术和生长参数自动测量（SFM）技术的临床使用价值。方法使用SF技术和传统超声技术对2018年8月至2019年1月南方医科大学附属深圳妇幼保健院妊娠16～41周正常连续单胎1005例进行丘脑水平横切面（A）、上腹部水平横切面（B）和股骨长轴切面（C）3个标准切面的识别与获取,测量双顶径（BPD）、头围（HC）、腹围（AC）和股骨长（FL）4个生长参数。另选择60例胎儿进行2种技术观察者内和观察者间重复性测量分析;运用Wilcoxon带符号秩检验比较2种技术进行切面识别与获取以及参数测量所需的时间;使用组内相关系数评价传统超声与SF技术测量的一致性,并评价SF技术切面获取及生长参数测量的准确率。结果与传统超声技术相比,SF技术测量的重复性更好。使用SF与传统技术测量4个生长参数的组内相关系数分别为0.998、0.995、0.998、0.998。通过判定,使用SF技术识别与获取标准切面A、B和C成功率分别为98.00%、99.10%和99.60%,测量BPD、HC、AC和FL成功率分别为100%、100%、99.60%和100%。无论是同时进行切面自动识别、获取与参数测量,还是单独进行参数测量时,SF技术明显比传统技术用时短[21.26（5.24）s vs 52.24（14.90）s;2.78（0.66）s vs 35.70（8.25）s],差异均具有统计学意义（Z=-27.366、-27.352,P均＜0.001）。结论 SF技术可自动化、智能化识别、获取胎儿超声3个标准切面,并对4个生长参数进行自动化测量,该技术在切面识别与获取的成功率和生长参数自动测量的准确性高,并可极大地减少标准切面获取及测量的时间,是一项智能、精准、高效的产前超声检查技术。

Objective To determine the transverse sections of corpus callosum on two-dimensional ultrasound and to establish the reference ranges for fetal corpus callosum dimensions on the transverse sections of normal foetus from 20 weeks to full term. Methods From June 2018 to December 2018, 10 singleton fetuses with no structural abnormalities diagnosed by prenatal ultrasound were selected as study subjects at Shenzhen Maternal and Child Health Hospital, whose parents consented to autopsy at 20-30 weeks of pregnancy due to inevitable abortion for ″cervical incompetence″ or ″unplanned birth″. A series of transverse sections obtained by three-dimensional oblique technique and frozen autopsy specimens were observed, and the characteristics of each section were summarized. The stable sections of corpus callosum on the transverse section were selected. From June 2018 to December 2018, 670 singleton pregnant women underwent routine ultrasound examination at the Ultrasound Department of our hospital. The corpus callosum diameters including the longest diameter of the corpus callosum, left to right genu diameter, anterior to posterior genu diameter, left to right splenium diameter, anterior to posterior splenium diameter, left to right body diameter, and anterior to posterior body diameter, and the angle of genu and splenium were measured at the cross-sectional plane mentioned above. Forty fetuses were randomly sampled and tested for repeatability between the two measurements. The normal reference ranges of the parameters of corpus callosum on the transverse section of the brain of each gestational week were established, and the correlation between the measured data and the scatter plot of gestational week was analyzed in parallel to establish regression equations. Results Three cross sections of corpus callosum obtained by the two different methods showed the same anatomical structures. There was no significant difference in the repeatability test between two observers. The scatter plots showed that the parameters of normal fetal corpus callosum were positively correlated with gestational age (r=0.232, 0.343, 0.284, 0.182, 0.913, 0.895, 0.748, 0.787, 0.736, 0.684, and 0.734, respectively, P<0.01). The regression equations were Y=0.514X+ 52.214, Y=0.785X+ 42.897, Y=0.600X+ 47.327, Y=0.436X+ 53.056, Y=0.117X+ 0.019, Y=0.070X-0.169, Y=0.013X+ 0.054, Y=0.065X+ 0.180, Y=0.014X+ 0.064, Y=0.047X+ 0.547, and Y=0.027X-0.116, respectively. Conclusions The serial transverse sections based on 3D oblique technique and frozen autopsy specimens are relatively stable and can be used to evaluate the structure of corpus callosum. The reference charts for normal fetal corpus callosum of different gestational ages may be useful for prenatal evaluation of congenital corpus callosum anomalies. Key words: Transverse section; Fetus; Corpus callosum; Second and third trimesters; Reference charts