Diagnostic ultrasound ( PDFDrive )

1536 PART V Pediatric Sonography
A
B
C
D
FIG. 45.30 Alobar Holoprosencephaly. (A) Coronal sonogram shows single central ventricle (V) and fused thalami (T). No falx or interhemispheric
issure is present. (B) Magnetic resonance image and (C) pathology specimen show single central ventricle and fused thalami. (D) Autopsy specimen
shows cebocephaly (severe hypotelorism and malformed nose).
conirm this appearance and typically shows sylvian issures
connecting abnormally across the midline. 63-66
DISORDERS OF SULCATION AND
CELLULAR MIGRATION
Schizencephaly
Believed to be caused by a primary neuronal migration malformation
in utero, schizencephaly has been reported in familial cases
and in early prenatal injury from drug abuse and abdominal
trauma, vascular insult, or toxin. 67 It causes gray matter–lined
clets that extend through the entire hemisphere, from the
ependymal lining of the lateral ventricles to the pial covering of
the cortex. he clets may be bilateral or unilateral (Fig. 45.31).
here may be wide openings of the clets (open-lip schizencephaly).
In some cases the clet is closed (closed-lip schizencephaly)
and may require MRI for diagnosis, because gray
matter–white matter diferentiation is not well demonstrated on
sonography. Most of these patients develop seizures, hemiparesis,
and variable developmental delay. he severity is related to the
amount of brain involved. Some patients with schizencephaly