Diagnostic ultrasound ( PDFDrive )

1558 PART V Pediatric Sonography
Subdural
fluid collections
Subarachnoid space
A
S
B
C
FIG. 45.55 Subdural and Subarachnoid Fluid Collections. (A) Drawing shows vessels are compressed onto the surface of the brain in
subdural luid collections and vessels cross the luid in subarachnoid space. (B) Magniied coronal color Doppler image of interhemispheric issure
in a 2-week-old infant. Large bilateral echogenic subdural effusions from meningitis compress the supericial cortical vessels onto the cortical
surface. (C) Coronal color Doppler image of interhemispheric issure in a 1-month-old infant. Large left and small right hypoechoic chronic subdural
hematomas (S) from nonaccidental trauma lie above the echogenic subarachnoid luid. The cortical surface is compressed by the echogenic
subarachnoid luid, which surrounds supericial cortical vessels (arrows) separated from the relatively lucent subdural luid by echogenic and
thickened pia-arachnoid (arrowheads). Note the echogenic subcortical white matter and superior sagittal sinus.
mental retardation or developmental delay, and spasticity or
seizures may result from infection at critical times during gestation.
Ultrasound plays an important role in identifying and
following both antenatal and neonatal complications from
congenital infections, with MRI showing additional indings in
many cases. 191,192
he most frequent congenital infections are commonly referred
to by the acronym TORCH. his refers to the infections Toxoplasma
gondii, rubella, CMV, and herpes simplex virus type 2
(HSV-2). he O stands for “other,” such as syphilis. Syphilis causes
acute meningitis, infrequently resulting in parenchymal lesions
in the newborn. 193
Of the TORCH group, congenital infection by CMV is the
most common, occurring in approximately 1% of all births. 194
CMV may be acquired at or ater birth with little or no consequence,
but prenatal infections may result in serious damage to
the developing brain. 195,196 Maternal infection is usually subclinical.
Maternal immunity to CMV reduces the risk of CMV in utero,
and vaccines are being considered. 197 Toxoplasmosis is the second
common congenital infection and is caused by the unicellular
parasite T. gondii. 198,199
he severity of the infection with either CMV or toxoplasmosis
depends on the timing of the infection during gestation. Earlier
infection, before 20 to 24 weeks, results in more devastating
outcomes: microcephaly, lissencephaly with abnormal myelination,
a hypoplastic cerebellum, polymicrogyria and cortical dysplasias,
porencephaly, and multicystic encephalomalacia. 200 CMV has
been reported to cause schizencephaly in some patients 69,70 (Fig.
45.56). Ventriculomegaly may result from brain volume loss.
Later infection, ater 24 weeks, will result in less severe neurologic
damage.
To diferentiate CMV from toxoplasmosis, serum titers for
antibodies against these organisms are useful. Other diferentiating
criteria include the petechial skin lesions and hepatomegaly