Fetal Anatomy by Three-Dimensional Ultrasound

A major goal of perinatal care is to accurately diagnose fetal anomalies prior to birth. This
capability allows clinicians to make prudent decisions regarding antepartum care, delivery
site, and postnatal therapy. Three-dimensional ultrasound is a recent technology that
provides a new way to evaluate the fetus. This technique allows one to scan through a digital
ultrasound volume dataset, visualize organs from different perspectives, measure volumes, and
render anatomical features through computer processing. However, the accurate
characterization of fetal anomalies by this technique must be interpreted in relation to
normal fetal anatomy at different stages of pregnancy.

We are continuing to develop an image reference library of fetal anatomy by identifying key
diagnostic features by three-dimensional ultrasound. A cross-sectional observational study of
up to 7,000 fetuses will catalog a broad spectrum of congenital malformations at various
gestational ages. A subset of the fetuses enrolled in this protocol will also be examined by
Magnetic Resonance Imaging (MRI) to identify potential advantages and limitations of this
imaging modality when compared to 3DUS for the diagnosis of congenital anomalies. The
protocol will include up to 400 examples of normal fetal anatomy by three-dimensional
ultrasonography.

All cases will be placed into a digital image database. For each anomaly category, volume
data will be acquired at specific gestational ages. Key diagnostic features will be
documented and correlated with postnatal outcome. Postnatal correlative studies may include
ultrasound, MRI, X-ray, computerized tomography (CT), and photography. We anticipate that our
results will permit improved diagnostic interpretation of congenital defects throughout
pregnancy.

- INCLUSION CRITERIA:

All pregnant subjects will be recruited under informed consent at either Hutzel or William
Beaumont Hospitals.

The study population for both arms of this protocol will involve pregnant women greater
than or equal to 15 years.

CROSS-SECTIONAL ARM OF PROTOCOL - NORMAL FETUS SUBJECTS:

3DUS STUDIES:

No fetal anomalies suspected by 2DUS.

Excellent visualization of normal fetal anatomy by 2DUS.

Accurate dating criteria by 1st trimester scan and/or menstrual history.

FETAL MRI STUDIES:

Gestational age between 18-42 menstrual weeks.

No known fetal abnormalities.

CROSS-SECTIONAL ARM OF PROTOCOL - ABNORMAL FETUSES:

3DUS STUDIES:

Congenital anomaly suspected by 2DUS.

Accurate dating criteria by 1st trimester scan and/or menstrual history.

FETAL MRI STUDIES:

Gestational age between 18-42 menstrual weeks.

Suspected fetal abnormalities.

POSTMORTEM STUDIES:

Suspected fetal abnormalities by prenatal ultrasound.

EXCLUSION CRITERIA:

CROSS-SECTIONAL ARM OF PROTOCOL - NORMAL FETUS SUBJECTS:

3DUS STUDIES:

Poor visualization of the fetus due to technical factors (e.g. obesity, surgical scar).

History of noncompliance with prenatal visits with the current or prior pregnancy.

FETAL MRI STUDIES:

Inability of the patient to fit in bore of MRI system.

Metallic implants that would increase risk to patient.

Previous occupational exposure to metal shop.

History of claustrophobia.

CROSS-SECTIONAL ARM OF PROTOCOL - ABNORMAL FETUSES:

3DUS STUDIES:

Poor fetal visualization from technical factors (e.g. obesity or decreased amniotic fluid).

FETAL MRI STUDIES:

Inability of the patient to fit in bore of MRI system.

Metallic implants that would increase risk to patient.

Previous occupational exposure to metal shop.

History of claustrophobia.

POSTMORTEM STUDIES:

Refusal to sign informed consent for postmortem imaging studies.