1. 18-19 JUNE 2013
Part 1/3
Ultrasound Training Course

3. Introduction
• Neurosurgery has the privilege to benefit from long time
experience and evolution of techniques of many
neighbour disciplines using ultrasound since several
decades.
• The application at the ICU showed a bedside use,
resulting in decrease of risky out door examination
reduce stress for our patients and logistic efforts for the
professionals.
• Investigations are running in innovative applications like:
– brain death diagnosis,
– bedside-sono-CT,
– aneurysm- monitoring,
– bridging-vein monitoring,
– sono-pupillometry.

4. ApplicationsFetal Neurosonogram
Cranial ultrasonography (CUS)
Intraventricular Haemorrhage of the
Newborn
Pathologic conditions with increased resistive index
CSDH
Assessment of Ventricular
Shunt Patency by Sonography
Spinal ultrasound in infants
Craniocervical junction
Transcranial Insonation: Vascular
Intracranial Occlusion
Extracranial-Intracranial Bypass
Transcranial Doppler Sonography
In Underwent Decompressive
Craniectomy For Traumatic Brain Injury
Acute Stroke: Perfusion Imaging
Sonothrombolysis:
Experimental Evidence
Endovascular Application of Ultrasound
Acute Stroke: Therapeutic
Transcranial Doppler Sonography
Cerebral Aneurysms
Cerebral
Arteriovenous
Malformations
Intracranial dural arteriovenous (DAVF)
Carotid Cavernous Fistulas
Cerebral Veins and Sinuses
Temporal Arteritis
Deep Venous Thrombosis
Functional Transcranial
Doppler Sonography
Pain: Non-invasive functional
neurosurgery using ultrasound
Non-invasive functional
neurosurgery using ultrasound
Measurement of optic nerve sheath diameter by
ultrasound: a means of detecting acute raised
intracranial pressure in hydrocephalus

5. Fetal Neurosonogram
• Detailed evaluation of the fetal CNS (fetal
neurosonogram) is also possible but requires specific
expertise and sophisticated ultrasound machines.
• This type of examination, at times complemented by
three-dimensional ultrasound, is indicated in pregnancies
at increased risk of CNS anomalies.
• Most basic examinations are satisfactorily performed
with 3–5-MHz transabdominal transducers.
• Fetal neurosonography frequently requires transvaginal
examinations that are usually conveniently performed
with transducers between 5 and 10 MHz
• Three dimensional ultrasound may facilitate the
examination of the fetal brain and spine

6. Fetal Neurosonogram
• Transabdominal sonography is the technique of choice
to investigate the fetal CNS during late first, second and
third trimesters of gestation in low risk pregnancies.
• Two axial planes allow visualization of the cerebral
structures relevant to assess the anatomic integrity of
the brain.
– transventricular plane and the transcerebellar plane.
• A third plane, the so-called transthalamic plane, is
frequently added, mostly for the purpose of biometry.
• Structures that should be noted in the routine
examination include the lateral ventricles, the cerebellum
and cisterna magna, and cavum septi pellucidi.

7. Fetal Neurosonogram

8. Fetal Neurosonogram

9. Fetal Neurosonogram

10. Fetal Neurosonogram
• Head circumference increases by about 1 mm daily
between 26 and 32 weeks’ gestation;
• Between 32 and 40 weeks it increases by 0.7 mm daily.
• An increase of 2mm per day is considered excessive,
although this is difficult to detect with certainty over a
single day – 4mm over two days

11. Cranial ultrasonography (CUS)
• In the neonate and young infant, the fontanels and many
sutures of the skull are still open, and these can be used
as acoustic windows to “look” into the brain.
• Transfontanellar CUS allows the use of high-frequency
transducers, with high near-field resolution.
• CUS is a reliable tool for detecting congenital and
acquired anomalies of the perinatal brain and the most
frequently occurring patterns of brain injury in both
preterm and full-term neonates.

12. Major advantages of CUS
• It can be performed bedside,
with little disturbance to the
infant; manipulation of the infant
is hardly necessary.
• It can be initiated at a very early
stage, even immediately after
birth.
• It is safe; (safety guidelines are
provided by the British Medical
Ultrasound Society
www.bmus.org and the American
Institute of Ultrasound in
Medicine www.aium.com)
(British Medical Ultrasound
Society 2006, American Institute
of Ultrasound in Medicine 2006).

13. Major advantages of CUS
• It can be repeated as often as necessary, and thereby
enables visualisation of ongoing brain maturation and the
evolution of brain lesions.
• In addition, it can be used to assess the timing of brain
damage.
• It is a reliable tool for detection of most haemorrhagic,
cystic, and ischaemic brain lesions as well as
calcifications, cerebral infections, and major structural
brain anomalies, both in preterm and full-term neonates.
• CUS is relatively inexpensive compared with other
neuro-imaging techniques.

15. Technical aspect of CUS
• The transducers should be appropriately sized for an
almost perfect fit on the anterior fontanel
• To allow good contact between the transducer and the
skin, transducer gel is used.
• The distance between the transducer and the brain is
small, allowing the use of high-frequency transducers.
• In most circumstances, good images can be obtained
using a transducer frequency of around 7.5 MHz.
• This enables optimal visualisation of the peri- and
intraventricular areas of the brain.

16. Technical aspect of CUS
• For the evaluation of more superficial structures (cortex,
subcortical white matter, subarachnoid spaces, superior
sagittal sinus) and/or in very tiny infants with small
heads, it is advised to perform an additional scan, using
a higher frequency up to 10 MHz.
• If deeper penetration of the beam is required, as in
larger, older infants or infants with thick, curly hair or in
order to obtain a better view of the deeper structures
(posterior fossa, basal ganglia in fullterm infants),
additional scanning with a lower frequency (down to
about 5 MHz) is recommended.

18. CUS

19. Standard Views
a Coronal scan at the level of the trigone
of
the lateral ventricles.
b Parasagittal scan through the right
lateral ventricle

20. Cranial ultrasonography (CUS)
• Neonatal transcranial Doppler studies are used
following acoustic windows:
– Transfontanellar – through the anterior fontanelle,
mainly for the visualization of anterior cerebral artery,
internal carotid artery and basilar artery
– Transtemporal – through the temporal bone, for the
visualization of middle cerebral artery and posterior
cerebral artery
– Suboccipital – through the foramen magnum,
visualization of distal segments of vertebral arteries
and basilar artery
– Transorbital and Submandibular – are used only
occasionally

21. Cranial ultrasonography (CUS)
• Elevation of ICP in infants, resulting from hydrocephalus,
cerebral edema, and intracranial hemorrhage, may lead
to brain damage through diastolic hypoperfusion.
• TCD ultrasonography is an accepted noninvasive
method to quantify perfusion of intracranial arteries in
adults and children.
• The peak S and end D flow velocities are measured, and
the RI is calculated as (S – D)/S.
• Transcranial Doppler ultrasonography with pressure
provocation accurately identifies hydrocephalic children
who require cerebrospinal fluid drainage procedures.

22. Cranial ultrasonography (CUS)
• With a 5 MHz phased-array transducer using color
flow Doppler sonography, TCD ultrasonography was
performed through the anterior fontanelle in all patients
• The anterior cerebral artery or its pericallosal branch was
identified in the midsagittal plane.
• After a stable waveform was obtained over at least 5 s,
the image was frozen, and the RI in the anterior cerebral
artery was determined, with cursors identifying the peak
S and end D velocities in a standard fashion.

23. Cranial ultrasonography (CUS)
Doppler curve of pericallosal artery: PI – pulsatility index, RI – resistive index, PSV –
peak systolic blood flow velocity, EDV – end-diastolic blod flow velocity, MnV – mean
blood flow velocity, FlowT – flow time

24. Pathologic conditions with
increased resistive index
• Hypocapnia
• Hyperoxia
• Acute intracranial hypertension
• Intraventricular haemorrhage
• Brain infarction
• Congenital heart disease with left-right shunt
• Blood hyperviscosity
• Indomethacin
• Critically ill newborns – in severe arterial hypotension
with decreased cardiac output
• Brain death – the Doppler curve demonstrates diastolic
block or reverse diastolic blood flow at cerebral arteries.

25. Pathologic conditions with
decreased resistive index
• Hypercapnia
• Hypoxemia, hypoxia
• Seizures
• Inflammation – inflammatory brain congestion and the
cerebral vasodilatation
• Asphyxia
• Idiopathic respiratory distress syndrome
• Increased cardiac output, hypervolemia
• Increased central venous pressure

26. Intraventricular Haemorrhage of the
Newborn
• Occurs frequently in premature neonates.
• Cause post-haemorrhagic ventricular dilatation, often
requiring permanent CSF diversion
• Neonatal intracranial pressure is normally under
6mmHg, but in the context of untreated PHVD it may rise
to 10 to 15mmHg

27. Papile classification
• Grade I – subependymal haemorrhage;
• Grade II – IVH;
• Grade III – IVH with ventricular dilatation;
• Grade IV - IVH with ventricular dilatation
and parenchymal extension.

28. Ventricular index
• VI is measured from the falx to the lateral wall of the
body of the lateral ventricle
• 4mm over the 97th centile is the ‘action line’ at which
intervention is considered.
• Anterior horn width, measured diagonally (>4mm), third
ventricular width, measured in the coronal plane (>3mm)
and thalamo-occipital dimension, measured in the
sagittal plane (>26mm) as new criteria for PHVD

29. Intraventricular Haemorrhage of the
Newborn

31. CSDH

32. Assessment of Ventricular
Shunt Patency by Sonography
• A sonographic means of assessing shunt function offers the
advantage of simultaneously imaging the ventricular catheter,
determining its location, and assessing the etiology of shunt failure.
• Its usefulness is limfted to pediatric cases in which an adequate
transfontanelle cranial sonographic study can be obtained and to
individuals with large cranlotomy defects.
A, Parasagittal sonogram of infant with Amold-Chiari nates at
thalamocaudate groove.
B, Increased echogenicity within the shunt malformation. Tram-track
echogenicity representing ventricular shunt termi- (arrow) caused by
microbubbles during digital compression of reservoir.

33. Abdominal ultrasound in the
diagnosis of cerebrospinal fluid
pseudocysts complicating
ventriculoperitoneal shunts
longitudinal ultrasound section of cystic
structure with posterior sound
enhancement characteristic of
fluid collection.
Echogenic focus posterior margin of cyst
compatible with shunt tip.
A=anterior: P=posterior; H=head; F=foot.

34. Spinal ultrasound in infants
• Accepted as a first line screening test in neonates
suspected of spinal dysraphism (SD)
• Diagnostic sensitivity equal to MRI; SUS can be
performed portably, without the need for sedation or
general anaesthesia.
• In infants with occult SD, early diagnosis may be useful,
as SD may lead to distortion of the spinal cord and nerve
roots with growth.
• The examination is performed using a 7.5–10 MHz linear
probe in both the sagittal and axial plane along the entire
spine.

35. Spinal ultrasound in infants
• SUS is possible in the neonate owing to a lack of
ossification of the predominantly cartilaginous posterior
arch of the spine.
• The quality of ultrasound assessment decreases after
the first 3–4 months of life as posterior spinous elements
ossify,
• In most children SUS is not possible beyond 6 months of
age.
• However, the persisting acoustic window in children with
posterior spinal defects of SD enables ultrasound to be
performed at any age.

36. The normal neonatal spinal cord
• is displayed on ultrasound as a tubular hypoechoic
structure with hyperechoic walls

37. Spinal ultrasound in infants
• The central canal is hyperechoic, the so-called central
echo complex.
• The subarachnoid space surrounding the cord is
hypoechoic.
• The caudal end of the spinal cord corresponds with the
conus medullaris, which continues into the filum
terminale.
• The cauda equina is seen as echogenic linear structures
surrounding a hyperechoic filum terminale.
• The vertebral bodies are seen as echogenic structures
ventral to the spinal cord.

38. Spinal ultrasound in infants
• The level of the conus medullaris.
– In term infants the tip of the conus medullaris normally lies above
the mid level of the L2 vertebral body although there is a large
range of normality (from T10/11 to L2/3).
– In pre-term infants the tip of the conus lies between L2 and L4, i.e.
the level of the conus moves proximally with age.
– A low-lying cord may imply tethering
• The position of the cord in a dorsal/ventral or anterior
/posterior orientation.
– In normal infants the cord lies a third to half way between the
anterior and posterior walls of the spinal canal.
– If the cord lies more posteriorly, tethering should be suspected.

39. Spinal ultrasound in infants
• The presence of normal pulsatile movement of the cord
and nerve roots (tethering leads to an absence of
pulsatility).
• The thickness of the filum terminale (normal 2 mm or
less).

40. Craniocervical junction
• To examine the craniocervical junction, the neck must be
flexed.
• Routinely, sagittal and axial scans of the spinal cord are
obtained from the craniocervical junction to the conus
medullaris and cauda equina.

41. Craniocervical junction
Normal sagittal (A),
parasagittal (B), and
transverse sonograms (C) in a neonate viewed with the patient
prone, showing the normal craniocervical junction.
The arrowheads outline the cervical cord.
(cm = cistema magna, v =vermis, t = tonsil, m = medulla,
f = fourth ventricle.)

42. Transcranial Insonation: Vascular
• Insonation of the intracranial cerebral arteries, veins, and sinus is
performed with transcranial Doppler or color duplex sonography.
– The orbital window is mainly used to identify the ophthalmic
artery and carotid siphon, which can be detected in most
patients.
– The temporal window allows the investigation of the anterior,
middle, and posterior cerebral and the terminal (C1) segment of
the internal carotid arteries, and the deep middle cerebral and
basal veins in 80–84% of cases.
– The foraminal window is used to assess the intracranial (V4)
vertebral and basilar arteries, which are detected in 79–94% and
89–96%, respectively.

43. Types of Doppler image
• Pulsed Doppler
– The transducer operates like in conventional ultrasound, as
transmitter and receiver of ultrasound, transmitting very short
pulses with a specific frequency called Pulse Repetition
Frequency.
– A new pulse cannot be emitted until having received the
previous one.
– Time interval between transmission and reception determines
the depth at which the Doppler shift occurs.
– Pulsed Doppler obtains in vascular flow a spectrum of velocities,
or spectral Doppler.
– The combination of spectral Doppler and B-mode image is
known as duplex Doppler.

44. Types of Doppler image
• Color Doppler
– This technique overlaps a color image on the conventional gray-
scale realtime sonographic image.
– The speed and direction are color coded.
– Usually, red is used to represent the flow directed towards the
transducer and blue the flow flowing away.
– The brighter colors correspond to higher speeds and darker
shades to lower speeds.
• Power Doppler
– Alternative way of color Doppler in which a sum of the power or
amplitude of the received signal is obtained, representing the
signal power at each point in the examination area.
– It will be directly proportional to the number of erythrocytes
present in it.

45. Thank You