Three-dimensional sonographic volume measurement of the fetal cerebellum

Purpose The objective of this longitudinal study was to evaluate the growth of the fetal cerebellum in normal pregnancy by using three-dimensional ultrasound. Methods Three-dimensional sonographic examinations were performed for 13 appropriate-for-gestational-age fetuses. Fetal cerebellar volume was measured every 2 to 3 weeks after 20 weeks of gestational age until delivery. The common multiplanar technique was used to calculate the fetal cerebellar volume. Results A curvilinear relationship was found between gestational age and cerebellar volume (R² = 78.6%, P < 0.0001), and normal ranges of cerebellar volume measurements for estimating the growth of the fetal cerebellum during normal pregnancy were generated. The data gathered in this study were fairly comparable with previous data obtained using three-dimensional ultrasound. However, the normal ranges of cerebellar volume that we determined were relatively wide throughout pregnancy. Conclusions Our findings suggest that a standard curve for fetal cerebellar volume using three-dimensional ultrasound can play a role in the evaluation of normal cerebellar growth in the fetus. However, we do cast doubt on the reliability and reproducibility of cerebellar volume measurement using three-dimensional ultrasound. Further studies involving a larger sample size and another technique (the rotational method with VOCAL) would be needed to confirm these findings.     

Three-dimensional sonographic measurement of fetal renal volume

Objective The objective of this longitudinal study was to evaluate the growth of the fetal kidney in normal pregnancies using three-dimensional ultrasound. Methods Three-dimensional sonographic examinations were performed on 13 appropriate-for-gestational-age fetuses. Fetal renal volume was measured every 2 to 3 weeks after 20 weeks gestational age until delivery. Results There was a good linear correlation between left and right renal volumes (r = 0.9614, P < 0.0001). Curvilinear relationships were found between gestational age and left and right renal volume (left: R² = 79.1%, P < 0.0001; right: R² = 74.2%, P < 0.0001), and normal ranges of left and right renal volume measurements for estimating the growth of the fetal kidney during normal pregnancy were generated. There was a difference for each predicted value of the fetal renal volume in the third trimester of pregnancy in our study and in two other previous studies. The left and right fetal renal volume to estimated fetal weight ratios were constant during the pregnancies studied. Conclusion Our findings suggest that fetal renal volume measurement plays a role in assessment of the growth of fetal kidneys. However, we are doubtful about the reproducibility of fetal renal volume measurements made by using three-dimensional ultrasound in utero. Further studies involving larger sample sizes are needed to reevaluate the usefulness and reproducibility of fetal renal volume measurements.     

Prenatal assessment of normal fetal humerus volume by three-dimensional ultrasound

Because fetal humerus dysplasia is associated with a variety of congenital syndromes, prenatal assessment of the fetal humerus growth is very important. The fetal humerus volume is one of the indexes in evaluating the humerus growth, but it has never been studied by 3-D ultrasound (US) in utero. To establish a normal reference chart of the fetal humerus volume for clinical use, we undertook a prospective and cross-sectional study using 3-D US to assess the fetal humerus volume in normal pregnancy. A total of 216 singleton fetuses that ranged between 20 and 40 weeks of gestation and fit the criteria of normal pregnancies were included in this study. Our results showed that the fetal humerus volume is highly correlated with the gestational age (GA). Using GA as the independent variable and the humerus volume as the dependent variable, the best-fit regression equation was humerus volume (mL) = 0.0044GA² − 0.0841GA + 0.6874 (r = 0.97, n = 216, p < 0.0001). For clinical use, a chart of normal growth centiles of the fetal humerus volume was then established based on this equation. In addition, the common indexes of fetal biometry, such as biparietal diameter, occipitofrontal diameter, head circumference, abdominal circumference, femur length and estimated fetal weight, were all highly correlated with the humerus volume (all p < 0.0001). In conclusion, our data of the fetal humerus volume assessed by 3-D US can serve as a useful reference in evaluating the fetal humerus growth during normal gestation. (E-mail: fchang@mail.ncku.edu.tw)     

三维超声测量胎儿肾脏及其血流容积与孕龄的相关性研究

目的探讨三维超声测量胎儿肾脏体积及肾脏血流容积与孕龄相关关系。方法应用三维超声重建技术测量89例(150枚肾脏)正常胎儿肾脏体积(Vr)及肾脏血流容积(Vf)并计算其比值(Vi)。结果①胎儿肾脏体积(Vr)与孕龄呈正相关(r=0.895,P<0.01);②胎儿肾脏血流容积(Vf)与孕龄呈正相关(r=0.752,P<0.01);③胎儿肾脏体积(Vr)及肾脏血流容积(Vf)的比值(Vi)与孕龄无明显相关性。结论三维超声可较准确测量胎儿肾脏及其血流容积,二者与孕龄呈线性正相关。     

Assessment of fetal adrenal gland volume using three-dimensional ultrasound

To assess the normal fetal adrenal gland volume during normal gestation, we performed a prospective study on 119 normal fetuses with gestational age ranging from 21 to 40 weeks using a 3-D ultrasound (US) volume scanner with a pure cross-sectional design. Polynomial regression analysis was calculated to find the best-fit model between gestational age (GA) and adrenal gland volume. In addition, estimated fetal weight (EFW) was also measured to demonstrate the correlation between adrenal gland volume and fetal weight. Our results showed that fetal adrenal gland volume is highly correlated with GA. Furthermore, using GA as the independent variable and adrenal gland volume as the dependent variable, the best-fit regression equation was adrenal glands volume (mL) = -0.2683 x GA + 0.0082 x GA(2) + 3.1927 (r = 0.93, n = 119, p < 0.0001). For clinical use, a chart of normal growth centiles of fetal adrenal gland volume in utero was then calculated based on this equation. In addition, fetal adrenal gland volume during normal gestation is also highly correlated with EFW (p < 0.0001). In conclusion, our data of fetal adrenal gland volume assessed by 3-D US can serve as a useful reference in evaluating fetal growth status during gestation.     

Three-dimensional sonographic measurement of liver volume in the small-for-gestational-age fetus.

OBJECTIVE: To assess the growth of the fetal liver in normal pregnancies and to evaluate the ability of fetal liver volume measurement for prediction of small-for-gestational-age fetuses. METHODS: Three-dimensional sonographic examinations were performed on 14 appropriate-for-gestational-age and 10 small-for-gestational-age fetuses. Liver volume and liver length were measured every 2 weeks after 20 weeks' menstrual age until delivery. RESULTS: A curvilinear relationship was found between the menstrual age and liver volume (R2 = 88.4%; P < .0001), and a normal range of liver volume measurement for estimating the growth of the fetal liver during normal pregnancy was generated. Liver length was normal in 7 of 10 small-for-gestational-age fetuses, whereas liver volume values in all small-for-gestational-age fetuses were below normal ranges in the mid to late third trimester. CONCLUSIONS: Our findings suggest that liver volume may be a useful measurement for diagnosing small-for-gestational-age fetuses in the mid to late third trimester but that liver length may not be predictive. Further studies involving a larger sample size would be needed to confirm this suggestion.     

Reproducibility of 3-dimensional sonographic measurements of fetal and placental volume at gestational ages of 11-18 weeks

PURPOSE: Determine the reproducibility of 3D ultrasound (3DUS) measurements of fetal and placental volumes. METHODS: We included 34 pregnant women between gestational weeks (GW) 11-18. Two operators independently acquired fetal and placental volumes using 3DUS. Each volume was acquired twice and stored on disk for off-line analysis. Intra- and interobserver reproducibility was expressed in the intra- and interclass correlation coefficient (intra-CC and inter-CC). In addition, the 3DUS volumes acquired by the first operator were calculated by the second and vice-versa to evaluate the effect of volume acquisition and caliper placement. A value >0.75 was considered a good agreement. RESULTS: Fetal and placental volume measurements were successful in 97% of all cases. Between GW 11-14 and 14-18 the median fetal volume was 20.8 (5.0-35.1) and 51.7 (37.9-132.8) ml, the median placental volume was 71.3 (40.9-111.9) and 120.7 (94.2- 273.7) ml. Bland-Altman plots were used for statistical analysis. The intraobserver reproducibility was good for fetus (intra-CC: 0.99; 0.99) and placenta (intra-CC: 0.99; 0.98). Also, interobserver reproducibility was good for fetus (inter-CC 0.98) and placenta (inter-CC 0.98). In addition, regardless of the operator who acquired the volumes, the inter-CC remained good for both fetus (inter-CC: 0.99; 0.99) and placenta (inter-CC: 0.97; 0.99). CONCLUSION: The reproducibility of fetal and placental volume measurements by 3DUS between GW 11-18 is good. In addition, individually chosen caliper placement and volume acquisition has no effect on the calculation of either volumes.     

三维超声测量胎儿肺体积及其在常见胎儿肺病变随访中的应用

目的利用三维超声技术测量胎儿肺体积,建立肺体积正常值范围,评价胎儿肺发育。方法选择显示满意的300胎18～36周正常胎儿肺三维容积图像,利用VOCAL技术测量其左、右肺体积,并对肺总体积(TLV)与孕周(GA)进行回归分析。随机抽取20胎正常胎儿TLV测值进行可信度分析。对4胎超声诊断为肺囊性腺瘤样畸形或隔离肺胎儿进行随访,测量其TLV,与正常胎儿TLV行散点图比较,观察其变化趋势。结果胎儿肺三维图像满意者占91.74%(300/327)。正常胎儿TLV随GA增加而增大,最适回归方程为:TLV=1.139-1.418GA+0.093GA2(r=0.99,P<0.01)。三维超声测量胎儿TLV的可信度很高(内部一致性系数为0.99,组内相关系数为0.99)。4胎肺病变胎儿TLV均随GA增加而增大,但变化趋势各不相同。结论三维超声能够很好地测量胎儿肺体积,在评价胎儿肺发育中具有重要作用。     

胎儿外耳畸形的三维超声观察

正胎儿外耳畸形居出生缺陷第五位~([1]),其发病率近年明显上升,临床上中耳、外耳畸形常同时发生,外耳的畸形程度间接反映了中耳的畸形程度~([2])。本组通过分析20例外耳畸形胎儿的声像图特征,旨在提高三维超声对胎儿外耳畸形的诊断水平。资料与方法一、临床资料选取2014年3月至2016年7月在我院规律产检并分娩的孕妇21 856例,年龄18~46岁,平均(27.6±2.6)岁;诊断时孕     

实时三维超声对胎儿唇腭裂的诊断价值

目的应用实时三维超声成像诊断胎儿唇腭裂,就其诊断价值与二维超声诊断进行比较探讨。方法应用esaote Mylab 90实时三维超声显像仪,三维容积探头和二维腹部探头,对2798例16～40周胎儿唇部进行观察。结果 2798例中,应用实时三维或二维超声能看到胎儿唇部者2644例,显示率为94.5%,看不清胎儿唇部者154例。二维显示率为84.6%(2367/2798),实时三维显示率为89.7%(2510/2798)。应用实时三维或二维超声共发现胎儿唇腭裂畸形11例,与引产或足月产后相符合。二维及实时三维超声产前均检出唇腭裂10例,漏诊1例,检出率90.9%(10/11)。结论实时三维超声在诊断胎儿唇裂中图像逼真直观,对二维图像具有重要的补充作用,二者结合诊断胎儿唇腭裂是更有效的方法。     

Three-dimensional volume sonographic study of fetal anatomy: intraobserver reproducibility and effect of examiner experience.

OBJECTIVE: The purpose of this study was to evaluate the accuracy of 3-dimensional (3D) sonography in assessing fetal anatomy and to determine the intraobserver reproducibility and the effect of examiner experience. METHODS: Three-dimensional volumes of the head, face, thorax, and abdomen were obtained for 40 fetuses. The volume data sets obtained were explored offline with multiplanar navigation and tomographic ultrasound imaging on a personal computer. Each case was examined twice by the same observer at least 3 months apart. The percentage for identification of fetal anatomic structures, 2-dimensional (2D) and 3D measurements, and the time spent on 2D and 3D examinations were calculated and compared. RESULTS: Ninety-two percent of fetal anatomic structures were identified with multiplanar navigation and tomographic ultrasound imaging. The genitals, the entry of the vena cava, and the ears were visualized in less than 70% of cases. Tomographic ultrasound imaging allowed viewing of 14 structures not seen in the multiplanar study. Intraobserver agreement for anatomic examinations was good (kappa = 0.78). Intraobserver agreement for fetal measurements showed differences between both examinations that approached 0 and intraclass correlation indices close to 0.9. The mean 2D scanning time +/- SD was 10.11 +/- 2.5 minutes, and the acquisition time for the 3D volumes was 1.54 +/- 0.35 minutes. The total time for the second 3D study was 7.23 +/- 1.17 minutes, significantly shorter than the 9.96 +/- 1.53 minutes spent on the first study (P < .001). CONCLUSIONS: Three-dimensional volumes are highly effective for complete fetal anatomic surveys. They show excellent intraobserver reproducibility and take less time to study as the examiner's experience increases.     

The interobserver reliability of ovarian volume measurement is improved with three-dimensional ultrasound, but dependent upon technique

The effect of measurement technique on the interobserver reliability of ovarian volume calculation from three-dimensional (3-D) ultrasound (US) data was investigated. Ovarian volume was calculated in 20 patients by two observers using both the “prolate ellipsoid formula” and a new 3-D rotational technique (VOCAL). There was a significant difference between observers in mean ovarian volume calculated by the prolate ellipsoid formula (31.54 mL vs. 26.54 mL: p < 0.05), which proved to be a significantly less reliable technique than 3-D rotational volume calculation with VOCAL. Image quality was significantly better (p < 0.001) and measurements were significantly more reliable (p < 0.05) in the B-plane than in the C- plane of the multiplanar display. Rotational measurement of ovarian volume from 3-D US data is significantly more reliable between observers than volume estimation from 2-D parameters using the prolate ellipsoid formula, but is dependent upon image quality, which is significantly better in the B-plane than in the C-plane. (E-mail: nick.fenning@nottingham.ac.uk)     

三维超声在膈疝胎儿肺容积测量中的应用

目的：评价三维超声测量先天性膈疝（Congenital diaphragmatic hernia, CDH）胎儿肺容积的准确性,并初步探讨CDH胎儿肺容积改变规律。方法：对10例拟引产的CDH胎儿于引产前1~3d应用三维超声体积自动测量技术（Virtual organ computer-aided analysis, VOCAL）测得其肺容积值,引产后6h内对胎儿进行病检,用水置换法得到其实际容积。同时测量150例正常对照组胎儿肺容积,并与CDH胎儿进行统计学比较。结果：①三维超声测量CDH胎儿肺容积与病检结果间有较好的相关性,相关系数（r）为0.79,偏倚及95%一致性界限分别为0.68cm3及（－4.59~3.24）cm3;②CDH胎儿肺容积较同孕周对照组明显减小。结论：先天性膈疝时胎儿肺脏受压体积明显缩小;三维超声测量CDH胎儿肺容积的准确性较好,可能成为评估其肺发育不良程度的重要方法。     

A sonographic study of fetal cystic hygromas

Fetal cystic hygromas are fluid filled sacs of lymphatic origin occurring in the posterolateral neck. Based on an experience with 15 of these hygromas diagnosed antenatally, the various sonographic appearances are illustrated and differential diagnostic features are discussed. A midline septum or hydrops may serve as diagnostic clues. The sonographic and anatomic features of a hygroma are correlated using a gelatin embedding technique.     

早孕期孕囊容积与胎儿孕龄相关性的三维经阴道超声研究

目的探讨早孕期(5～12周)孕囊容积与胎儿孕龄的相关性。方法应用三维经阴道容积超声获取210例早孕期拟行终止妊娠治疗孕妇的孕囊容积图像,使用三维超声影像工作站4D-view软件测量孕囊的容积和直径,容积测量方法为VOCAL法,孕囊直径为长、宽和厚径的平均值。根据末次月经确定胎儿孕龄。对所测得结果进行统计学分析,确定胎儿孕龄与孕囊容积和直径相关性的密切程度。结果 210例孕妇中146例符合制定的标准,数据进行统计学分析。结果显示:孕妇年龄16～41岁,平均(26.80±5.57)岁;胎儿孕龄35～84d,平均(45.58±8.39)d;孕囊容积(GSV)0.008～89.943ml,平均(5.46±11.65)ml;孕囊直径(GSD)0.077～7.009cm,平均(1.88±1.25)cm;孕囊容积的平方根与孕龄表现很强的相关性(R2=0.806;P0.001),孕囊直径与孕龄亦有较强的相关性(R2=0.684;P0.001);孕囊容积的平方根与胎儿孕龄的相关性确定系数明显高于孕囊直径与胎儿孕龄的相关性确定系数。结论孕囊直径和孕囊容积的平方根与胎儿孕龄均有较密切相关性,但孕囊容积是早孕期预测孕龄的一个更好的指标,可更准确地预测胎儿孕龄。研究结果还需要进一步证实。     

三维超声体积自动测量系统精确测量甲状腺体积

目的 观察三维超声体积自动测量系统(VOCALTM)在甲状腺体积精确测量中的应用价值.方法 应用GE Voluson 730三维超声成像系统对水囊模型及活体甲状腺体积进行二维和三维测量.结果 ①三维超声测量的水囊模型体积与实际体积之间的相关性明显好于二维超声测量.三维超声的测量结果 更接近于实际体积.②在活体甲状腺上,以三维超声精确测量的甲状腺体积作为参考标准,利用直线回归方程推导出一个更为精确的二维超声测量甲状腺的新体积公式,根据此公式测算得出的甲状腺体积较传统的椭球体公式测算结果 误差小.结论 VOCALTM技术在精确测量甲状腺体积方面有较高的准确性和可重复性.     

胎儿Dandy-Walker畸形的产前超声诊断

目的研究产前超声检查在胎儿Dandy-Walker 畸形诊断中的价值.方法回顾性总结5例胎儿Dandy-Walker 畸形的超声表现,以及相关的胎儿中枢神经系统(CNS)和CNS外畸形.结果 5例胎儿产前超声检查均可见Dandy-Walker 畸形的典型超声表现,其中4例伴发CNS外畸形.结论产前超声检查可以有效检出胎儿Dandy-Walker 畸形.     

三维容积成像在甲状腺实性结节诊断中的应用

目的 探讨三维容积成像在甲状腺实性结节良恶性鉴别中的应用价值。方法 对119例甲状腺实性结节手术患者共144个结节行二维及三维超声检查,利用三维容积及断层技术行三维重建,分析良恶性结节的冠状面成像特征,评价其诊断价值。结果 144个结节中,良性结节75例,恶性结节69例。冠状面成像特征中,良恶性结节的形态、边界、边缘有无成角或毛刺、内部回声及有无微钙化差异均有统计学意义(P均<0.05)。建立Logistic回归模型,最终进入模型的甲状腺恶性结节冠状面成像特征包括形态不规则、边缘成角或毛刺、低回声。三维超声诊断甲状腺恶性实性结节的敏感度为92.75%(64/69),特异度为85.33%(64/75),准确率为88.89%(128/144),均高于二维超声[89.86%(62/69),80.00%(60/75),84.72%(122/144)],但两者的诊断效能差异均无统计学意义(P均>0.05)。结论 在三维冠状面成像中,甲状腺良恶性结节的特征差异显著。三维容积成像在甲状腺实性结节的良恶性鉴别诊断中具有重要的价值。