A cross-sectional study of simplified grade of the transcalvarial axial plane in evaluating the convexity sulci of normal fetuses
10.3760/cma.j.cn131148-20240328-00187
- VernacularTitle:产前超声经颅顶部横切面简化分级方法评估正常胎儿外表面脑沟的横断面研究
- Author:
Yue QIN
1
;
Huaxuan WEN
;
Dandan LUO
;
Qing ZENG
;
Meiyu ZHENG
;
Meiling LIANG
;
Yimei LIAO
;
Xin WEN
;
Bocheng LIANG
;
Ying YUAN
;
Shengli LI
Author Information
1. 深圳市妇幼保健院超声科,深圳 518028
- Keywords:
Ultrasonography;
Fetus;
Convexity sulci;
Cerebral cortex;
Grade
- From:
Chinese Journal of Ultrasonography
2024;33(10):884-890
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To study the stability and morphological changes of the convexity sulci in normal fetuses between 20 and 32 weeks, and to explore the simplified grade for evaluating the convexity sulci development and analyzing its clinical significance.Methods:This study was a cross-sectional analysis. A total of 551 cases of normal singleton pregnancies between 20 and 32 weeks of gestation were retrospectively collected, who underwent routine ultrasound examinations at Shenzhen Maternity and Child Healthcare Hospital from September 2019 to June 2022. The display of the far-field convexity sulci on the transcalvarial axial plane was observed as 0 for not displayed and 1 for displayed.Further, based on the morphology and number of convexity sulci, they were classified into five grades: no sulcus displayed (grade 0), one sulcus (grade 1), two sulci (grade 2), three sulci (grade 3), and four or more sulci (grade 4). The gestational age at examination and pregnancy outcomes were recorded. The distribution characteristics of gestational weeks for each grade of the convexity sulci were analyzed, and the gestational week distribution of the left and right convexity sulci was compared to analyze bilateral symmetry. The Weighted Kappa coefficient was used to analyze inter-observer and intra-observer consistency, and curve regression analysis was employed to establish a model for predicting grade based on gestational weeks.Results:Before 25 weeks of gestation, the convexity of the fetal cranial vertex was completely smooth.The central sulcus consistently appeared after 26 weeks, while the superior frontal sulcus, intraparietal sulcus, postcentral sulcus, and precentral sulcus consistently appeared between 28 and 31 weeks. Among these, the superior frontal sulcus had a lower display rate before 29 weeks. By 32 weeks, all convexity sulci of the cranial vertex should be visible. Three hundred and eleven fetuses were graded for the left, and 240 fetuses were graded for the right. The developmental grade of the convexity sulci increased from Grade 0 to Grade 4 as the gestational age progressed. Grade 0 appeared between 20-26 weeks, grade 1 between 25-28 weeks, grade 2 between 26-28 weeks, grade 3 between 27-30 weeks, and grade 4 between 27-32 weeks. The distribution of grade did not differ significantly between the left and right sides of grade 0, 1, 3 and 4 (all P>0.05), while there was a significant difference in the distribution of gestational age between the convexity sulci of grade 2 ( P<0.05). The Weighted Kappa coefficients for intra-observer and inter-observer consistency were 0.94 and 0.86, respectively, indicating strong consistency. Conclusions:The simplified grade for assessing the development of convexity sulci in normal fetuses on the transcalvarial axial plane via prenatal ultrasound can provide a preliminary evaluation of the maturation of convexity sulci in fetuses between 20 and 32 weeks of gestation.