Sonography of fetal spine using 3-D/ 4-D ultrasound reveals greater detail of
the fetal spine in 3-Dimensions. Ultrasound visualizes the ossified part of the
fetal spine. The 3 main ossification centers in the fetal vertebrae are: a) the
centrum b) the right neural process and c) the left neural process. The centrum
forms the central part of the vertebral body. The postero-lateral parts of the
vertebrae are formed by the right and left neural processes. (These 3-D
ultrasound images are courtesy of Dr. PK Srivastava, India, and Dr. Ravi Kadasne,
UAE).
In this fetus, sonography of the lumbosacral spine shows a major defect in
the posterior part of the fetal lumbar and sacral vertebrae due to failure of
closure of the dorsal part of the vertebrae (the laminae and spinous processes).
The ultrasound image in top row- Left, shows 2-D (B-mode) display of the large
defect in long section. The image on top-row- Right, shows the same appearance
in 3-D ultrasound. The post natal photograph of the area (lower back) shows the
open spinal canal. This type of spina bifida is called spina bifida cystica.
(Ultrasound images of spina bifida are courtesy of Dr. Martin Horenstein,
Argentina).
Neural tube defect and sac at the level of fetal thoracic spine:
This 3rd trimester fetus showed a sac herniating from a defect (spina bifida)
in the thoracic vertebrae. Sonography of the fetal brain showed ventriculomegaly.
These ultrasound images suggest a diagnosis of meningocele of thoracic spine/
vertebrae in fetus. Meningocele of thoracic vertebrae is a rare entity.
Ultrasound images are courtesy of Dr. Prasenjeet Singh, India.
A: CORONAL SECTION SPINE:
B: TRANSVERSE AND SAGITTAL SECTIONS
C: TRANSVERSE AND SAGITTAL SECTIONS D: SHOWING THE CLUB
FOOT
E: FETAL CLUB FOOT:
F: FETAL FOOT:
These are ultrasound images of a 2nd trimester fetus, which show a neural
tube defect (spina bifida) of the lower lumbar vertebrae. There is also splaying
of the vertebral laminae and widening of the interpedicular distance in this
region. A small cystic soft tissue mass is seen overlying (dorsal) this part of
the spine (meningocele). Also note the associated fetal club foot anomaly.
Normally, the fetal foot is seen perpendicular to the plane of the fetal leg. In
this case, the angle with the ipsilateral leg is altered and the foot is almost
parallel to the leg. Images courtesy of Dr. Ravi Kadasne, UAE.
References: for more images and information on fetal club foot and neural
tube defects, please see: