Clinical trial NCT00826917: Use of 3D/4D Ultrasound in the Evaluation of Fetal Anomalies
Official title: Use of 3D/4D Ultrasound in the Evaluation of Fetal Anomalies - The Use of Volumetry by Three Dimensional Ultrasound in the First Trimester
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Homozygous αº-thalassemia
Hb Bart's Disease
Keywords: 3D, 2D, ultrasound, volumetry, multiplanar, VOCALTM, XI VOCALTM, fetal, gestational sac, placenta
Lead sponsor: The University of Hong Kong
Sponsor class: OTHER
First posted: 2009-01-22
Enrollment: 195
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Sampling method: PROBABILITY_SAMPLE
Study population: 1. Use of XI VOCALTM in 3D fetal volumetry measurements,comparison with multiplanar and VOCALTM

   -restropective(2005-2007),30 singleton pregnancies,11-14 weeks' gestation, at risk of homozygous αº-thalassaemia.
2. Use of XI VOCALTM in 3D placental volumetry measurements,comparison with multiplanar and VOCALTM

   -retrospective(2005-2007), 32 singleton pregnancies,11-14 weeks' gestation at risk of homologous alphaº thalassaemia.
3. Comparison of 3DUS volumetry measurement between two models of ultrasound machine -prospective(December 2007-June 2008),30 singleton normal pregnancies,11-14 weeks' gestation.
4. Use of 3DUS in fetal, gestational sac and placenta quotient measurement, fetuses at risk of homozygous αº-thalassemia(Hb Bart's disease) -retrospective(datasets July 2007-Dec 2008),singleton pregnancies,11-14 weeks' gestation,26 affected cases,34 unaffected cases,43 normal control.

Brief summary: Volumetry measurements can be a potential clinical use as non-invasive tools in prenatal diagnosis and screening and helps to reduce the risk and complications of invasive procedures. 3DUS volumetry gives more precise results than 2DUS volumetry measurements, particularly, of irregularly shaped objects.

Detailed description: Conventionally volume measurements can be made by using multiplanar or VOCALTM (Virtual Organ Computer-aided AnaLysis). Recently, a new technique, XI VOCALTM (eXtended Imaging VOCAL) has been described. Combined with the inversion mode, measurements for the liquid-filled structures can also be made. The potential use in clinical diagnosis and prediction of pathologies of volume measurements particularly in the first trimester are yet to be investigated.

3D ultrasound is found to be superior to 2D parameter in volumetry measurement. However, currently, there are still very few studies done to evaluate the potential use of volumetry measurement in clinical practice, especially of the validity and reproducibility of XI VOCALTM; and the variation of results obtained within different ultrasound machines. Due to the potential use of volumetry measurements in clinical practice, the accuracy in volumetry measurement is very important and the development of new technique need to be fully explored so that its benefits can be fully used for the contribution of clinical practice.

So far no research has been done to evaluate the difference in the results obtained between different ultrasound machines, in particularly for volumetry measurements. This is important because if there is no significant difference in results between difference machines, we can accumulate the results from these machines for a study, which can include a more variety of samples. Furthermore, it will be much easier to compare results of one machine with another for similar studies.

Both Voluson 730 and Accuvix have been used widely in research studies on 3D volumetry but comparison of the results obtained from these two machines have not been done. We do not know whether the results generated from one machine can be extrapolated to the other machine for clinical or research purpose. Thus more research needs to be done in this area.

Thus, this study is carried out to evaluate the potential use of the new modality of XI VOCALTM in the volumetry measurement of regular and irregular shaped objects, comparison of results obtained between different widely used machines, and the potential used of volumetry measurements in the prediction of common and important clinical pathologies such as αº-thalassemia.

Eligibility criteria: Inclusion Criteria:

For objective 1 and 2 - Samples are recruited from our prenatal diagnostic clinic at Ysan Yuk Hospital between 11-14 weeks' gestation. They are those who come for routine scan and those who are referred from the general antenatal clinics of the same hospital which pregnancies are at risk of homologous alphaº thalassaemia.

For objective 3 - Recruitment are the same as above except samples are obtained from normal pregnancy.

For objective 4 - Recruitment are the same as above. However, study is divided into intervention group and control group. For the intervention group, data is collected from pregnancies at risk of of homozygous αº-thalassemia while for the control group, data is collected from normal pregnancies.

Exclusion Criteria:

* If women refuse to participate in the study
* Patients with other co-existing illnesses

Primary outcomes:
measure: Objective 1:The use of XI VOCALTM in 3D volumetry measurements of fetal head and trunk of fetuses from 11 to 14 weeks gestation and known volume phantoms and its comparison with the conventional multiplanar and VOCALTM technique
timeFrame: 18 months
measure: Objective 2:The use of new modality of XI VOCALTM in 3D volumetry measurements of placenta from 11 to 14 weeks gestation and known volume phantoms and its comparison with the conventional multiplanar and VOCALTM technique
timeFrame: 18 months
measure: Objective 3:The use of 3DUS in the volumetry of first trimester pregnancy and in vitro study: comparison between two models of ultrasound machine
timeFrame: 18 months
measure: Objective 4:The use of 3DUS in the measurement of fetal, gestational sac and placenta quotient of fetuses at risk of homozygous αº-thalassemia (Hb Bart's disease) at 11 to 14 weeks' gestation
timeFrame: 18 months
Secondary outcomes:
Other outcomes:
Locations:
city: Hong Kong
country: China
facility: Tsan Yuk Hospital
state: Hong Kong
Study officials:
affiliation: The University of Hong Kong
name: Kah Bik Cheong, BSc(Hons), MMedSc, MBBS
role: PRINCIPAL_INVESTIGATOR
affiliation: The University of Hong Kong
name: Kwok Yin Leung, MBBS, FHKAM
role: STUDY_DIRECTOR
References:
citation: Leung KY, Cheong KB, Lee CP, Chan V, Tang MHY, Lau ETK. Prenatal diagnosis of homozygous α°-thalassemia: from an invasive to a noninvasive approach. Expert Reviews. 2009.4(3): 321-329.
citation: Leung KY, Cheong KB, Tang MHY, Chan V. Prenatal Diagnosis of Thalassaemia. JPOG. 2008. 34(1): 37-42.
citation: Leung KY, Cheong KB, Lee CP, Chan V, Lam YH, Tang M. Ultrasonographic prediction of homozygous alpha0-thalassemia using placental thickness, fetal cardiothoracic ratio and middle cerebral artery Doppler: alone or in combination? Ultrasound Obstet Gynecol. 2010 Feb;35(2):149-54. doi: 10.1002/uog.7443.
citation: KY Leung, KB Cheong, MHY Tang. 2D and 3D Ultrasound Prediction of Homozygous αº-thalassemia. Donald School Journal of Ultrasound in Obstetrics and Gynecology, April-June 2010;4(2):123-126.
citation: Cheong KB, Leung KY, Li TK, Chan HY, Lee YP, Tang MH. Comparison of inter- and intraobserver agreement and reliability between three different types of placental volume measurement technique (XI VOCAL, VOCAL and multiplanar) and validity in the in-vitro setting. Ultrasound Obstet Gynecol. 2010 Aug;36(2):210-7. doi: 10.1002/uog.7609.
citation: Cheong KB, Leung KY, Chan HY, Lee YP, Yang F, Tang MH. Comparison of inter- and intraobserver agreement between three types of fetal volume measurement technique (XI VOCAL, VOCAL and multiplanar). Ultrasound Obstet Gynecol. 2009 Mar;33(3):287-94. doi: 10.1002/uog.6255.
citation: Cheong KB, Leung KY, Chan HY, Chen M, Tang MHY. Comparison of volumetry fetus, gestational sac, and placenta obtained from two three- dimensional ultrasound machines. 18th World Congress on Ultrasound in Obstetrics and Gynecology. Ultrasound Obstet Gynecol. 2008; 32: 400.
citation: Cheong KB, Leung KY, Chan HY, Chen M, Tang MHY. Comparison of volumetry of fetus, gestational sac, and placenta in normal pregnancies obtained by two kinds of three dimensional ultrasound machines. 4th Asia Pacific Congress inMaternal Fetal Medicine. 17Th - 19th October, 2009. Macau Tower Convention and Entertainment Center, Macau, SAR China.
citation: Cheong KB, Leung KY, Li TK, Chan HY, Lee YP, Tang HY. Comparison of inter- and intraobserver agreement between three different types of placental volume measurement techniques (XI VOCALTM, VOCALTM and multiplanar). 13rd -17th Sept 2009. Ultrasound Obstet Gynecol. 2009. 34 (Suppl 1): 209.
citation: Cheong KB, Leung KY, Chan HY, Lee YP, Tang MHY. Comparison of inter- and intraobserver agreement between three different types of fetal volume measurement techniques (XI VOCALTM, VOCALTM and multiplanar). 13th Postgraduate Symposium, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, SAR China. 2008.
citation: KB Cheong, KY Leung, HY Chan, YP Lee, F Yang, MHY Tang. Comparison of inter- and intra-observer agreement between three different types of fetal volume measurement techniques (XI VOCAL, VOCAL, and multiplanar). 18th World Congress on Ultrasound in Obstetrics and Gynecology. Ultrasound Obstet Gynecol. 2008; 32(3):399.
citation: Cheong Kah-bik, Ng EHY.The use of volumetry by three-dimensional ultrasound in the first trimester. 2009. Postgraduate Thesis. The HKU Scholars Hub (thesis online).