Contribution of three-dimensional computed tomography in the assessment of fetal skeletal dysplasia.
OBJECTIVE
To compare the diagnostic accuracy of two-dimensional (2D) ultrasound and three-dimensional (3D) computed tomography (CT) for the diagnosis of fetal skeletal anomalies.


METHODS
Eleven pregnant women underwent 2D ultrasound and 3D-CT. Ten fetuses presented skeletal anomalies on 2D ultrasound and one fetus had a normal ultrasound exam but a familial history of osteopetrosis. We compared retrospectively the diagnoses established on 2D ultrasound and 3D-CT with the neonatal and/or postmortem work-up, which were used as the gold standard.


RESULTS
2D ultrasound provided the correct diagnosis in only two of the 11 cases. CT yielded the correct diagnosis in eight; in six of these, 2D ultrasound had been inconclusive. 3D-CT was more accurate than was 2D ultrasound in visualizing vertebral anomalies (abnormal shape of the vertebral bodies, abnormal interpedicular distance), pelvic bone malformations (delayed ossification of the pubic bones, abnormal acetabular shape) and enlarged metaphysis or synostoses in long bones. In three cases, neither 2D ultrasound nor CT provided the correct diagnosis.


CONCLUSIONS
In this series, which included a variety of skeletal dysplasias, 3D-CT had a better diagnostic yield than did 2D ultrasound. Both imaging techniques are useful in the management of fetal dysplasia; 2D ultrasound is a useful screening test and 3D-CT is a valuable complementary diagnostic tool.
Cassart
M
M
Department of Medical Imaging, Erasme University Clinics, and Department of Fetal Medicine, Brugmann Hospital, Brussels, Belgium. mcassart@ulb.ac.be
Massez
A
A
Cos
T
T
Tecco
L
L
Thomas
D
D
Van Regemorter
N
N
Avni
F
F
D001848:Bone Diseases, Developmental / Q000000981:diagnostic imaging*; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000196:embryology; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging*; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging; D005865:Gestational Age; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods; D012189:Retrospective Studies; D012272:Ribs / Q000000981:diagnostic imaging / Q000196:embryology; D013131:Spine / Q000000981:diagnostic imaging / Q000196:embryology; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016216:Ultrasonography, Prenatal / Q000379:methods