'Big-eyed frog' sign on spatiotemporal image correlation (STIC) in the antenatal diagnosis of transposition of the great arteries.
OBJECTIVE
To determine the value of simultaneous visualization of the cross-sectional view of both atrioventricular (AV) valves, the pulmonary artery and the aorta (en-face view of the AV valves and great vessels) in the identification of fetuses with transposition of the great arteries (TGA).


METHODS
This was a retrospective analysis of volume datasets obtained with the spatiotemporal image correlation (STIC) technique from 56 fetuses with and 30 fetuses without congenital heart defects. Volume datasets were reviewed offline to compare the en-face view of the AV valves and great vessels between fetuses with normal echocardiography and those with TGA.


RESULTS
The en-face view of both AV valves and great vessels in fetuses with TGA displayed the main pulmonary artery situated side-by-side with the aorta ('big-eyed frog' sign). In contrast, fetuses with normal hearts did not have this characteristic sonographic sign. This novel sonographic sign also helped to identify additional cases of TGA in 17 fetuses with complex heart defects.


CONCLUSIONS
The big-eyed frog sign may prove helpful in the prenatal diagnosis of TGA.
Shih
J C
JC
Department of Obstetrics and Gynecology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan. jcshih@ntu.edu.tw
Shyu
M K
MK
Su
Y N
YN
Chiang
Y C
YC
Lin
C H
CH
Lee
C N
CN
D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000196:embryology; D019561:Echocardiography, Four-Dimensional / Q000379:methods; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging* / Q000502:physiology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008943:Mitral Valve / Q000000981:diagnostic imaging; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D012189:Retrospective Studies; D018570:Risk Assessment; D014188:Transposition of Great Vessels / Q000000981:diagnostic imaging* / Q000196:embryology; D014261:Tricuspid Valve / Q000000981:diagnostic imaging; D016216:Ultrasonography, Prenatal