Neonatal Brain

CME ARTICLE

Navigating the Neonatal Brain Through the Base of the Skull
An Effective Sonographic Teaching Tool
Teresita L. Angtuaco, MD, FACR

Abstract: The neonatal head is routinely evaluated with ultrasound
within hours after birth. The most common images obtained are coronal and sagittal views using the anterior fontanel as a window. Routine scanning protocols should includerepresentative images of intracranial structures that are reproducible from one examination to another. The shape of the base of the skull can provide landmarks that
can ensure reproducibility of examinations using a minimum of 11
images. The use of these landmarks makes it possible to have a consistent technique to localize anatomic structures and pathology in
both planes.
Key Words: neonate, head,ultrasound, anatomy, brain
(Ultrasound Quarterly 2004;20:38–44)

LEARNING OBJECTIVES
After reading this article and completing the posttest, the
reader should be able to
• Identify the different planes of section through the neonatal
brain using ultrasound
• Describe the differences among anatomic structures included in each plane of section
• Locate pathology in the neonatal brain both inthe sagittal
and coronal planes
Ultrasound evaluation of the neonatal brain has become
routine in intensive care nurseries. Its ability to detect intracranial hemorrhage noninvasively has been proved to be reliable
and helpful in the daily management of premature neonates.1,2
Since the early 1980s, the anterior fontanel has served as the

Received for publication February 4, 2004; acceptedFebruary 10, 2004.
From the Professor of Radiology, Radiologic Technology, and the Obsetetrics
and Gynecology Director, Division of Imaging, University of Arkansas for
Medical Sciences, Little Rock, Arkansas.
The author has disclosed that she has no interests in or significant relationships
with any commercial companies pertaining to this educational activity.
Reprints: Teresita L. Angtuaco,MD, University of Arkansas for Medical Sciences, Department of Radiology #581, 4301 W. Markham, Little Rock,
AR 72205-7199 (e-mail: AngtuacoTeresitaL@uams.edu).
Copyright © 2004 by Lippincott Williams & Wilkins

38

window of choice in assessing the brain.3–5 With highfrequency transducers, detailed anatomy of the brain can be
demonstrated with great accuracy and reproducibility.Initially, 3 views were used: coronal, sagittal, and axial. Soon
after, the axial view was dropped, and currently only sagittal
and coronal images are obtained on a routine evaluation. In
recent years other acoustic windows have been proposed, such
as the mastoids, posterior fontanel, and lambdoid suture.6–8
These have been used when additional or complementary images are needed and in specialsituations when the anterior fontanel is not accessible.
In the daily performance of head ultrasound using
the anterior fontanel, it is important to have a standard set of
images that are obtained in every examination. To generate these image sets, appropriate landmarks need to be identified. The base of the skull can provide these appropriate landmarks.
At least 6 images are obtained in the coronalplane (Fig.
1), starting with the most anterior to the most posterior. In each
section certain structures are recognized and linked with the
shape of the skull forming the floor of the section.
Section 1 is obtained at the anterior cranial fossa. At this
level, the falx, frontal lobes, and occasionally the frontal horns
are seen. The base of the skull is shaped like the “hull of a
ship,”formed by the lesser wing of the sphenoid (Fig. 2).
Section 2 is obtained where the internal carotid arteries
bifurcate into the anterior cerebral and middle cerebral arteries
to form the Circle of Willis. In this section, the frontal horns of
the lateral ventricle, cavum septum pellucidum, and corpus
callosum are seen. The base of the skull in this anterior portion
of the middle cranial...