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Fig. 8.42 US for skull fracture. (a) Linear transducer: skull fracture sees as disruption of skull
echo. (b) Linear transducer: skull fracture with subacute haematoma
M. Riccabona
8.3.10 Tumours andSpace-Occupying Lesions
Intracranial tumours represent 15% of childhood tumours, most occurring beyond
rst year of life—therefore not ideally suitable for US diagnosis; in these ages only
large tumours depicted particularly if they cause midline shift or hydrocephalus:
• In infancy mostly teratoma, craniopharyngioma, medulloblastoma/PNET, choroid plexus papilloma and lipoma.
• Older children—larger variety of different tumours.
US Findings
Tumour echogenicity and texture—nonspecic: homogeneous or heterogeneous,
cystic or necrotic areas, haemorrhage and may contain calcications (only large
calcications cause acoustic shadowing).
Secondary signs—consequences of space-occupying lesions—shift/compres-
sion of surrounding structures, compression of ventricle and hydrocephalus.
Some specic appearances:
• Echogenic tumour typically in midline—rather specic for (callosal) lipoma.
• Choroid plexus papilloma—homogenously echogenic, within plexus, inhomogenous tumours may represent carcinoma; very vascular—CDS is helpful.
Additional imaging by preferably MRI or—if not available—CT.
Note
8.3.10.1 Vascular Malformations
Difcult to depict on US, particularly beyond rst months of life, contrast-enhanced
CDS may increase US potential.
Typical entity—phakomatosis (e.g. Klippel–Trénaunay syndrome, Von Hippel–
Lindau syndrome and Bourneville–Pringle disease), tubers and gliomas manifest
in more central portions or at ventricular margins—more easily depicted than
common peripheral or meningeal lesions (particularly venous ectasia with calcication and thrombosis) as in Klippel–Trénaunay, and easily missed → contrastenhanced MRI.
ab
bc
8 Neurosonography inNeonates, Infants andChildren
159
US Appearance
• Echogenic—if consisting of many small vessels.
• Tubular or cystic—if consisting of larger vessels and aneurysmal vascular portions (Fig.8.43).
• Show vivid Doppler ow only with large or high ow shunts: feeding and draining vessels depictable.
• Purely venous malformations have low ow—difcult to depict, particularly on
transcranial imaging.
• Ce-US may improve differentiation from other lesions.
aCDS: helpful particularly in neonates and young infants for:
• Vascular pathology: malformations and aneurysms (intra- and extracranial):
– Particularly typical arteriovenous malformation/stula of vein of Galen
(Figs.8.44a–c).
Fig. 8.43 (a) Axial view by TCI-CD: ow in aneurysmatic portion of a vein of Galen malforma-
tion, some feeding arteries seen as well as the enlarged draining vein (with high and turbulent ow
causing aliasing). (b) US appearance in a typical neonatal cerebral AVM—ectatic/aneurysmal vein
of Galen malformation. Midline sagittal view: large cystic formation lled with oating echoes—
vein of Galen malformation
a
Fig. 8.44 CDS in cranial and cerebral AVM. (a, b) Focal mass suspected to be a skin haemangi-
oma on the skull; CDS demonstrates vivid vascularisation. Note: Mirror image artefact both on
grey scale and on CDS caused by the highly reective skull bone. (c) Superior sinus thrombosis,
sagittal view: CDS demonstrates lack of ow in the superior sagittal sinus which is also somewhat
inhomogenously echogenic; consequently dilated extra-axial CSF space
160
M. Riccabona
Note In vascular malformations, CDS can be misleading, particularly after haem-
orrhage or with thrombotic components, often differentiation from tumours and
other mass lesions impossible.
• Venous thrombosis—poor insonation angle and low ow may impair conventional CDS potential (Fig.8.44d).
• Signicantly hyperperfused tumours (e.g. plexus papilloma—see Fig.8.38d):
– Otherwise aCDS not particularly useful for cerebral tumours.
– Potentially for DDx of necrotic parts or compartments containing compli-
cated uid (e.g. abscess).
CDS in older children: to some extent transcranial ce-CDS may improve sono-
graphic potential in depicting vascular malformations or differentiating clots, necrotic
areas or haemorrhages and subacute infarctions from tumours. Atypical ow patterns
may inbdicate shunt ow and allow rough estimation of hemodynamics.
8.3.11 Cerebral Calcifications
Introduction
Various causes: prenatal infection, peri- and postnatal meningitis, vascular malformations, posthaemorrhagic, neoplastic, phakomatoses, postthrombotic, etc.
Localisation
• Commonly in supratentorial brain, mostly in basal ganglia and also hemispheres.
• Commonly in vicinity of vessels and in choroid plexus.
• Calcication-like echoes in cysts or abscess-like formations—suspicion for parasitic or fungal infection, if in cyst wall—hint at unusual origin (infectious, posthaemorrhagic, tumourous, etc.).
Meningeal calcications difcult to depict on US.
Note
US Findings (See Fig.8.28a)
• Usually echogenic formations with sharp borders can be scattered and may vary
in size and echogenicity.
• Small calcications lack typical acoustic shadowing.
• Differential diagnosis of calcications difcult by US:
– Aetiology can only be assumed in combination with other imaging and par-
ticularly clinical information.
8.3.11.1 Non-calcifying Vasculopathy
(Lenticulostriate Vasculopathy)
Band-like echogenic stripes along vessels, mostly in the basal ganglia (see
Fig.8.28b).
8 Neurosonography inNeonates, Infants andChildren
161
8.4 Ultrasound oftheSkull
8.4.1 Introduction
US can be used for assessment of subcutaneous pathology as well as disruption of
skull surface.
Always use linear high-resolution high-frequency transducer and plenty US gel.
8.4.2 Haematoma
Types of haematoma—see Fig.8.36.
US helpful in differentiating entity:
• Echogenicity and US appearance may help estimate age:
– Acute bleed—rather hyperechoic.
– Older bleed—hypoechoic with sedimentation.
– Chronic bleed or remnants/seroma—anechoic, capsule formation.
8.4.3 Space-Occupying Lesions andTumours
US—resembles nding in other small parts (see respective chapter), may visualise
cysts, tumours, metastases, etc.
• US mostly unspecic—but will indicate and tailor further imaging.
• US helpful for DDx—erosion of tabula externa/only in soft tissue (epidermoid?)
cyst/lesion arising from bone (e.g., histiocytosis), severe destruction suspicious
for malignancy (e.g. sarcomatous tumours—Fig. 8.45).
8.4.4 Skull Fracture
• US depicts disruption of echogenic calvarial bone surface—helpful for assessing
suspicious ndings on plain lm (Fig.8.42).
• US may help analyse amount of displacement.
• US may help in follow-up—e.g. if growing fracture suspected.
US used to assess sutures and their ossication+ differentiating sutures from
fractures:
• Fracture—typically sharp border.
• Suture—dentates shape of borders, similar to plain lm; US also used to assess
craniosynostosis in some places.
162
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M. Riccabona
dc
*
Fig. 8.45 US of skull lesions: obvious destruction of mastoid bone penetrating deep—not typical
for mastoiditis, eventually proven to be a sarcoma: (a) Grey scale US showing the soft tissue mass
eroding mastoid bone. (b) CDS depicts irregular vessels within mass. (c) CT (arrow) and (d) MRI
(asterix) conrm osseous destruction and intracranial invasion of the soft tissue tumour
• 3DUS with surface rendering helpful for differentiation, conspicuously visualises shape of fracture (see respective chapter).
8.5 Additional Imaging
8.5.1 Plain Film
Used for visualisation of osseous structures.
• Particularly when looking for fractures, calcications, skull defects, skull anomalies, etc.
– Dedicated projections used for assessment of premature synostosis.
• Assess continuity of shunt drains.
8 Neurosonography inNeonates, Infants andChildren
163
8.5.2 CT
Indicated for emergency imaging, particularly in older children.
• After trauma, suspected haemorrhages and for complicated fractures (always
with surface rendering).
• Hydrocephalus/follow-up after shunt (use specic low-dose protocols)—if no
MRI available or contraindicated/unsuitable.
• Stroke (if MRI not available).
• Tumours (if MRI not available).
• CT-angiography used for vascular assessment:
– Modern volume CT and CT-DSA allow for angiography-like subtraction
images as well as perfusion studies.
Note Considerable radiation burden—try to replace by MRI whenever possible.
8.5.3 MRI
Ideal non-ionising imaging modality indicated for
• Assessment of brain parenchyma, maturation and myelination, metabolic disease, tumours, malformations, etc.
• MR angiography, diffusion weighted imaging, perfusion imaging, MR spectroscopy—helpful additional tools for dedicated queries.
Note Small children require sedation.
8.5.4 Catheter Angiography
For assessment of vascular problems, if interventional treatment is an option.
8.5.5 Additional Supporting Procedures
Fundoscopy, US of eye and orbit, lumbar puncture, brain pressure monitoring,
EEG, laboratory tests, etc.
Note Choice of diagnostic test depends on the clinical query, potentially also on
laboratory ndings, but mainly on patient age. Consider US rst whenever brain
sonographically accessible, even if only providing an orienting imaging approach
(allowing tailoring of additional diagnostic imaging).
164
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M. Riccabona
8.6 Ultrasound oftheEye andtheOrbit
8.6.1 Introduction
Ocular globe—ideal US window into orbit. Many queries can be approached, not
only within eye but also in deeper spaces. This is a simple and easy applicable technique that may reveal all necessary information and should be promoted, particularly in terms of radiation protection.
How to Perform
• Eyelid closed, warmed US gel placed and avoid pressure.
• Globe and orbit are visualised through closed eyelid with high-resolution linear
and sector arrays.
Note Reduce output gain to avoid heating of bulb uid (MI at lowest possible limit,
~0.1 to 0.3, up to maximal 0.5 for short time) and avoid (a)CDS unless necessary for
enabling diagnosis.
8.6.2 Normal Findings
Typically all major structures seen should be documented in two planes: anechoic
lens, corpus vitreum, smooth border of retina, outer contour of spheric bulb and
papilla just in front of attachment of optic nerve (Fig.8.46).
Behind eye: retrobulbar fat, optic nerve accompanied by nerve sheet and vessels
and major eye muscles.
Note Pictogram with denition of US plane using clocklike descriptions is helpful
for follow-up.
Fig. 8.46 Normal eye US. (a) Normal US appearance of eye ball and optic nerve. (b) CDS with
central vessels
8 Neurosonography inNeonates, Infants andChildren
165
8.6.3 Sonographically Depictable Pathology
Congestion of Papilla: Papilla swollen, elevation from retina can be measured, measurements vary with equipment and age.
Optic nerve sheet widened—associated with increased intracranial pressure
(Fig.8.47).
Foreign bodies: direct visualisation of foreign object, changes in consistency of
bulbar uid (glaucoma) and haemorrhage.
Retinal displacement: with or without adjacent pathology, coloboma, persistent
membranes, microphthalmia, etc.
Tumours: retinoblastoma, rhabdomyosarcoma, lymphoma, glioma, optic glioma,
orbital lymphangioma/haemangioma, etc. (DDx, e.g. congenital glaucoma, persisting embryonal vitreous body and artery, etc.) (Fig.8.48a, b, d, f):
• Orbital abscesses/inammation (Fig.8.48d):
– Commonly situated at thin osseous margin in median compartment adjacent
to ethmoid sinus, becomes sonolucent in case of thinning and decalcication
from inammation.
US of Adjacent Structures
Dacryocystocele—easily diagnosed:
• Cystic structure in median outer compartment of eye with dilated proximal nasolacrimal duct, usually containing echoes, which move under slight transducer
pressure (Fig.8.48d).
• Helps differentiation from ventral encephalo- or meningocele or tumour
conditions.
Fig. 8.47 Retrobulbar magnied view:
dilated optic nerve sheath (arrow). Dilated
optic nerve sheet (↔) in hydrocephalus
166
M. Riccabona
a
d
Fig. 8.48 Pathology depictable on US of the eye and orbit. (a) Retinoblastoma: echogenic mass
lling bulb. (b) CDS demonstrates irregular vessels within tumour arising from ophthalmic/retinal
artery (same patient as image a); (c) Retinocytoma: partially calcied mass with small complex
cystic components adjacent to optic papilla (+….+). (d) Orbital abscess (+ +) adjacent to bony
border with ethmoid sinus. (e) Dacryocystocele (+ +) of left eye. (f) Congenital glaucoma with
visualisation of vitreous artery
b
e
c
f
US for treatment guidance: instillation of sclerotherapeutic agents in lymphatic
malformations (see respective chapter). US guidance for manual decompression of
dacryocystocele by massage with gentle pressure, ...
Eye US—promising and helpful bedside noninvasive application, but rarely
Note
used. Further details can be found in the literature.
US oftheNeonatal Spinal Canal
andCord
MichaelRiccabona
9.1 Introduction
Vertebrae are not completely ossied in early childhood=spinal canal and content
accessible by US in neonates (and infants) to assess for normal as well as typical
pathological ndings.
9.2 Requisites
Spinal US possible as long as non-ossied posterior arches allow access to spinal
canal during rst months of life.
Thereafter, sonolucent vertebral disc can be used for limited views, but due to
ossied vertebral bodies and arches continuous assessment of spinal canal becomes
impossible.
9
9.3 Transducers andTechnique
Dorsal approach: standard access from midline, high-resolution high-frequency
linear transducers (18–5MHz).
Sagittal+axial sections performed throughout the entire region of interest:
• Baby or child placed in prone or decubitus position, supporting pillow/towel can
be helpful.
M. Riccabona (*)
Department of Radiology, Division of Pediatric Radiology, Medical University Graz
and University Hospital Graz, Graz, Austria
e-mail: michael.riccabona@klinikum-graz.at
© Springer Nature Switzerland AG 2020
M. Riccabona (ed.), Pediatric Ultrasound,
https://doi.org/10.1007/978-3-030-47910-7_9
167