Diagnostic ultrasound ( PDFDrive )

CHAPTER 46 Duplex Sonography of the Neonatal and Infant Brain 1583
A
B
C
D
FIG. 46.9 Seven-Week-Old Infant With Progressive Liver Failure, Severe Neurologic Deterioration, and Brain Death. (A) Initial ultrasound
study and pulsed wave Doppler tracing from anterior cerebral artery appear unremarkable. (B) Follow-up imaging during devastating neurologic
deterioration shows no relevant brain perfusion on power Doppler imaging. (C) Sagittal midline power Doppler imaging also fails to show venous
low within the superior sagittal sinus, conirming lack of brain perfusion. (D) Complete lack of brain perfusion was also conirmed by nuclear medicine
perfusion study.
decrease in the I/E ratio was more prominent for the EDV compared
with the peak systolic low velocity and time average low
velocity. 60
VASCULAR MALFORMATIONS
Pediatric cerebral arteriovenous malformations (AVMs) difer
substantially from adult forms in their angioarchitecture, clinical
presentation, systemic hemodynamic impact, and overall functional
outcome. 61 Pediatric AVMs are frequently istulous or
multifocal, oten exert a hemodynamic efect on the entire venous
system, and rarely manifest with high low–related vasculopathy
or low-related aneurysms. Systemic manifestations with cardiac
overload are a key clinical feature increasing morbidity and
mortality. Chronic venous stasis and/or ischemia in combination
with a vascular steal may cause chronic cardiac insuiciency
and result in irreversible brain damage. he so-called “melting
brain” is a well-known devastating complication of the vein of
Galen aneurysmal malformation (VGAM), which is the most
common neonatal intracranial vascular malformation. Diferentiation
between “true” and “false” VGAM is essential. 62 In the true
VGAM, arteries drain directly into a dilated, persisting interhemispheric
prosencephalic vein (Markowski vein) without
connection to the deep venous system. In “false” VGAM, subpial
AVMs adjacent to the cerebellum, brainstem, or deep supratentorial
territories drain into a normally developed vein of Galen,