Nero sonography- pediatrics head ultrasound - BY STEVE RAMSEY

Indication for Premature babies

Preterm refers to delivering prior to 37 weeks whilst apremature infant is one that has not yet reached the level of fetal development that generally allows life outside the womb.

- The fine network of vessels (the germinal matrix) on the floor of the anterior horn of the lateral ventricles (the ependyma) are extremely fragile.
- If there is any hypoxic episode, the reactive increase in blood pressure can result in a hemorrhage of these vessels.
- Usually assessed at day 1 and again at day 7.

Increased head circumference
Persisting large fontanel
Craniosynostosis (premature closure of sutures)
Trauma
Known hypoxia
Follow up of known pathology
Failure to thrive
Suspected intracranial mass or infection.

LIMITATIONS

if the anterior fontanel is very small or closed your visibility will be reduced or completely obscured. Even with a large fontanel, the peripheral extremes of the brain are obscured from view.

Probes:

Primarily a small footprint, wide sector, mid.-frequency probe is essential.
Ideally a specific 5-8 MHz vector probe however a trans-vaginal probe also provides excellent imaging. (A TV probe can be ergonomically difficult to use for some operators and awkward to ft in a humidicrib.)
You may also require a high frequency linear array to assess superficial structures and a curvilinear probe for axial trans-temporal images.

Environment:

A warm room with warm gel.
If still in high oxygen environment, this should be maintained as much as possible.
Patient position:
If still in a humidicrib as a high oxygen environment, the baby must be scanned there. You may need to place a cloth under and/or beside the baby’s head to support and immobilize it for the scan.

SCANNING TECHNIQUE

Use sufficient gel to not require too much transducer pressure.

Approach is generally via the anterior fontanel. The posterior fontanel can also be used.
Using the small footprint sector or TV probe:
- Begin in a coronal plane slowly sweeping from the anterior to the posterior.
- Rotate 90o to perform sagittal and para-sagittal views.
Using the high frequency linear probe:
- Gently scan through the anterior fontanel in transverse.
- You should assess the superior sagittal sinus for patency, and the sub-arachnoid space.
- You will usually be able to scan as deep as the 3rd ventricle.
Using the 5 MHz curvilinear probe: scan through the temple in an axial plane, particularly assessing the opposite subdural region.

Look for

A solid grasp of the intracranial anatomy is vital.
Also, a thorough understanding of the developmental evolution of the neonatal brain and how it changes between 28 weeks and term.
Essentially, the normal 10 week premature brain is relatively smooth, homogeneous & devoid of sulci/gyrae.

Sagiatl scan

Medline (must include corpus callosum the 3rd and 4th ventricles and cerebellum).
Parasagiattal to show caudothalamic notch and detail of lateral ventricles
Far lateral to show periventricular white matter.

Coronal