This document provides guidance on performing and interpreting neonatal cranial ultrasounds. It describes the acoustic windows used, standard scan planes, common brain abnormalities seen in premature infants like germinal matrix hemorrhage and periventricular leukomalacia, and methods for assessing and grading these conditions. Measurement techniques for identifying hydrocephalus, such as the Levene index and ventricular index, are also outlined.

1. Neonatal Cranial Ultrasound
Dr Mohit Goel
JR 1

2. The acoustic windows :
Anterior
Fontanel
The Standard
view window Posterior
Fontanel
Supplementary
view window
Mastoid
Fontanel
Supplementary
view window
Temporal
Supplementary
view window

3. Coronal Views
(at least 6 standard planes)

4. The orbital ridge forms the inferior boundary of this image.
First coronal plane (C1) at the level of the frontal lobes

5. Second coronal plane (C2) at the level of the frontal horns of the
lateral ventricles

6. Third coronal plane (C3) at the level of the third ventricle

7. Fourth coronal plane (C4) at the level of the bodies of the lateral
ventricles.
1. Interhemispheric fissure
8. Temporal lobe
9. Sylvian fissure
14. Body of lateral ventricle
15. Choroid plexus
16. Thalamus
17. Hippocampal fissure
18. Aqueduct of Sylvius
19. Brain stem
20. Parietal lobe
Brain stem

8. Fifth coronal plane (C5) at the level of the trigone of the lateral
ventricles

9. Sixth coronal plane (C6) through the parieto-occipital lobes

10. Sagittal Views (at least 5 standard
planes)
Standard Views(Anterior Fontanel)

11. Midsagittal plane (S3) through the third and
fourth ventricles
Cingulate sulcus
Thalamus
Cisterna quadrigemin
Pons
Medulla oblongata

12. Second and fourth parasagittal planes (S2, S4)
through the right and left lateral ventricles
Arrow indicates internal capsule
Choroid plexus

13. First and fifth parasagittal planes (S1, S5) through
the insulae (right and left)
Insula
Sylvian fissure

14. Supplemental Acoustic Windows

15. Coronal view, using the posterior fontanel as an acoustic
window
Falx
Calcarine fissure
Occipital horn of
lateral ventricle
Straight sinus
Tentorium
Cerebellum
(a: hemispheres; b: vermis)

16. Parasagittal view, using the posterior fontanel as an acoustic
window
Temporal lobe
Thalamus
Trigone of lateral
ventricle
Parietal lobe

17. Upper Transverse view using the left temporal
window
Mesencephalon
Interpeduncular fossa
Temporal lobe
Arrow indicates mesencephalic aqueduct

18. Lower transverse view using the left temporal
window
Pons
Prepontine cistern
Cerebellum
(a: hemispheres; b: vermis

19. Coronal view using the mastoid fontanel as an acoustic
window
Cisterna magna
Fourth ventricle
Pons

20. Transverse view using the mastoid fontanel as
an acoustic window
Occipitallobe
Temporal lobe
Arrow indicates fourth ventricle

21. (also known as periventricular hemorrhage or preterm caudothalamic
hemorrhage)
These germinal matrix hemorrhages occur in the highly vascular but also
stress sensitive germinal matrix, which is located in the caudothalamic
groove. This is the subependymal region between the caudate nucleus and
thalamus.
The germinal matrix is matured by 34 weeks gestation, such that hemorrhage
becomes very unlikely after this age.
Most GMHs occur in the first week of life
These hemorrhages start in the caudothalamic groove and may extend into
the lateral ventricle and periventricular brain parenchyma.
Germinal matrix hemorrhage (GMH)

22. Grade 1 and 2 bleeds generally have a good prognosis.
Grade 3 and 4 bleeds have variable long-term deficits

23. An intracranial hemorrhage confined to the caudothalamic groove.
It is staged as grade 1 hemorrhage.
In the acute phase these bleedings are hyperechoic, changing to iso- and hypo-
echoic with time.

24. Coronal and Sagittal US of a grade 2 hemorrhage
On the coronal image only the cavum septi pellucidi is seen.
Both lateral ventricles are filled with blood, but there is no ventricular
dilatation.

25. Intraventricular hemorrhage and hydrocephalus (Grade 3 GMH),
Coronal sonograms, and sagittal sonogram, show progressive hydrocephalus.
The ventricular walls have become very echogenic, caused by a chemical ventriculitis
from blood. The lateral and third ventricles are enlarged, and there is a clot in the back
of the third ventricle causing aqueductal obstruction.

26. Intraparenchymal
hemorrhage (grade IV
hemorrhage).
Parietal cortex
hemorrhage may
involve the motor area,
causing contralateral
hemiparesis.

27. Grade 4 intracranial hemorrhage
Originally these grade 4 hemorrhages were thought to result from subependymal
bleeding into the adjacent brain.
Today however most regard these grade 4 hemorrhages to be venous hemorrhagic
infartions, which are the result of compression of the outflow of the veins by the
subependymal hemorrhage. These venous infarctions resolve with cyst formation.
These cysts can merge with the lateral ventricle, finally resulting into a porencephalic
cyst.
grade 4 hemorrhage at a
later stage with extensive
cyst formation.

28. Peri Ventricular Leukomalacia (PVL)
PVL is also known as Hypoxic-Ischemic Encephalopathy (HIE) of the preterm.
It is a white matter disease that affects the periventricular zones.
In prematures this white matter zone is a watershed zone between deep and
superficial vessels.
PVL presents as areas of increased periventricular echogenicity.
PVL occurs most commonly in premature infants born at less than 33 weeks
gestation (38% PVL) and less than 1500 g birth weight (45% PVL).
Detection of PVL is important because a significant percentage of surviving
premature infants with PVL develop cerebral palsy, intellectual impairment or
visual disturbances.

29. Grading PVL
The pathogenesis of PVL has been found to relate to three major factors:
(1) the immature vasculature in the periventricular watershed;
(2) the absence of vascular autoregulation in premature infants, particularly in the
cerebral white matter; and
(3) the maturation-dependent vulnerability of the oligodendroglial precursor cell
damaged in PVL. These cells are extremely vulnerable to attack by free radicals
generated in the ischemia-reperfusion sequence.

30. PVL grade 1
PVL is diagnosed as grade 1 if
there are areas of increased
periventricular echogenicity
without any cyst formation
persisting for more than 7 days.
Increased periventricular
echogenicity is however a
nonspecific finding that must
be differentiated from the normal periventricular halo or normal hyperechoic
'blush' posterosuperior to the ventricular trigones.
Suspect PVL if the echogenicity is asymmetric, coarse, globular or more
hyperechoic than the choroid plexus.
The abnormal periventricular echotexture of PVL usually disappears at 2-3
weeks.

31. PVL grade 2
The images demonstrate a PVL grade 2 with small periventricular cysts.
The echogenicity has resolved at the time of cyst formation.
2% of the preterm neonates born before 32 weeks develop cystic PVL.
Cystic PVL has been identified on cranial ultrasounds on the first day of life,
indicating that the adverse event was at least 2 weeks prenatal rather than
perinatal or postnatal.

32. PVL grade 3
Sagittal image demonstarting extensive PVL grade 3
PVL is diagnosed as grade 3 if there are areas of increased periventricular
echogenicity, that develop into extensive periventricular cysts in the
occipital and fronto-parietal region.

33. PVL grade 4
PVL is diagnosed as grade 4 if there are areas of increased periventricular
echogenicity in the deep white matter developing into extensive subcortical
cysts.
PVL grade 4 is seen mostly in fullterm neonates as opposed to PVL grade 1-3,
which is a disease of the preterm neonate.

34. Flaring
The term flaring is used to describe the slightly echogenic periventricular
zones, that are seen in many premature infants in the first week of life
.
During this first week it is not sure if this is a normal variant or a sign of PVL
grade 1.
Flaring persisting beyond the first week of life is by definition PVL grade 1.
Follow up is needed to differentiate flaring from PVL grade I.

35. HYDROCEPHALUS
Anechoic cerebrospinal fluid is seen above thalamus (T)
Hydrocephalus results from an imbalance between CSF production and its drainage
by the arachnoid villi.

37. Ventricular measurement
Coronal section through the lateral ventricles slightly posterior to the foramen of Monro
is taken.
3 echogenic dots representing the choroid plexus in the lateral ventricles and in the roof
of the third ventricle are seen.
Furthermore symmetrical image of the Sylvian fissure on both sides and the
hippocampus (green and orange arrows) should be seen.

38. Levene index
Up to 40 weeks of gestational age the Levene-index should be used and after 40 weeks
the ventricular index.
The Levene index is the absolute distance between the falx and the lateral wall of the
anterior horn in the coronal plane at the level of the third ventricle.
These measurements can be compared to the reference curve and are quite usefull for
further follow-up.

39. Ventricular index
Ventricular index
After 40 weeks the ventricular index or frontal horn ratio should be used, i.e. the ratio of
the distance between the lateral sides of the ventricles and the biparietal diameter.

40. THANK YOU