Reproducibility of fetal heart volume by 3D-sonography using the XI VOCAL method.
BACKGROUND
To assess the reliability of fetal heart volume measurement by three-dimensional sonography (3DUS) using the eXtended Imaging Virtual Organ Computer-aided AnaLysis (XI VOCAL) method.


METHODS
This reliability study enrolled 30 pregnant women with singleton healthy pregnancies between 19 and 34 weeks of gestation. All volume acquirements were performed with a convex volumetric transducer (C3-7ED) coupled to an Accuvix XQ sonography device (Medison, Korea). The XI VOCAL 10 planes was the method of choice for volumetric measurement. 3D datasets were analyzed by two observers (EQSB and HJFM); fetal heart volume was measured twice by the first and once by the second observer to calculate intra and interobserver reproducibility. Statistical analysis used pareated Student's t test (p) and calculated Intraclass correlation coefficients (ICC). Bland-Altman plots were also constructed.


RESULTS
We observed an excellent intra- and interobserver reliability for fetal cardiac volume assessed by XI VOCAL. For the intraobserver the ICC was 0.998 (95% CI: 0.997; 0.999), with mean of differences of 0.12 cm3 (95% limits of agreement: -0.84; +0.84; p = 0.130). For interobserver the ICC was 0.899 (95%CI: 0.996; 0.998), mean of differences 0.05 cm3 (95% limits of agreement: -0.84; +0.84; p = 0.175).


CONCLUSIONS
Fetal cardiac volume assessed by 3DUS using XI VOCAL method is highly reproducible between 19 to 34 gestational weeks.
Barreto
Enoch Q
EQ
Department of Obstetrics, São Paulo Federal University, São Paulo, SP, Brazil.
Milani
Hérbene F
HF
Araujo Júnior
Edward
E
Haratz
Karina K
KK
Rolo
Liliam C
LC
Nardozza
Luciano M
LM
Guimarães Filho
Hélio A
HA
Moron
Antonio F
AF
D000293:Adolescent; D000328:Adult; D002306:Cardiac Volume; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D015588:Observer Variation; D011247:Pregnancy; D015203:Reproducibility of Results; D016216:Ultrasonography, Prenatal; D055815:Young Adult
Lancet. 1986 Feb 8;1(8476):307-10
2868172
Ultrasound Obstet Gynecol. 2003 Mar;21(3):283-91
12666225
Ultrasound Obstet Gynecol. 1997 Jan;9(1):42-8
9060130
Ultrasound Obstet Gynecol. 2006 Feb;27(2):128-33
16388511
Ultrasound Obstet Gynecol. 2009 Mar;33(3):287-94
19248036
Ultrasound Obstet Gynecol. 1996 Jun;7(6):429-34
8807760
Fetal Diagn Ther. 2004 Jan-Feb;19(1):87-91
14646426
Circulation. 1998 Aug 11;98(6):562-6
9714114
Arch Gynecol Obstet. 2007 Jul;276(1):95-7
17219156