Diagnostic ultrasound ( PDFDrive )

1152 PART IV Obstetric and Fetal Sonography
Primary
palate
Nostril
Lip
Incisive
foramen
Alveolus
Secondary
palate
A
Uvula
B
C
FIG. 33.21 Patterns of Clefting of Lip and Palate. (A) Normal anatomy of lip, primary palate, and secondary palate. The primary palate
encompasses features anterior to the horizontal line, and the secondary palate is posterior to the blue line. (B) Isolated unilateral cleft lip involving
the lip and nose. (C) Complete unilateral cleft lip and palate. The cleft lip extends through the primary palate, through the incisive foramen, and
through the secondary palate. (D) Bilateral cleft lip and palate. This cleft extends on both sides through the nose, lip, primary and secondary palate
(Courtesy of Andrew S. Phelps, MD.)
D
Associated Signs of Cleft Palate With Cleft
Lip
AXIAL AND CORONAL VIEWS
Lips: cleft
Nares: lattened or deformed
Vomer: deviated away from side of cleft; often midline if
bilateral cleft lip and palate
Maxilla: interrupted alveolus, wide gap
Orbits: hypertelorism
SAGITTAL VIEWS
Proile: midface retrusion
Tongue: high position in oropharynx
Unilateral Cleft Lip or Palate
Unilateral clets occur more oten on the let side. In a unilateral
clet lip or palate, there is oten an ofset between the two sides
of the clet, which are described as the “greater segment” on the
side opposite the clet, and the “lesser segment” on the side of
the clet (Fig. 33.24).
Bilateral Cleft Lip or Palate
Only about 10% of facial clets are bilateral. In bilateral clet lip
or palate, the midsagittal view will oten show an abnormal
premaxillary protrusion of sot tissue anterior to and above the
normal position of the upper lip (Fig. 33.25). Bilateral clet lip
and palate may be symmetrical or asymmetrical (Fig. 33.26).
Median Cleft Lip or Palate
Median clet lip is a classic inding in alobar holoprosencephaly.
In these cases, head size is small for menstrual dates and there
is hypotelorism. 90 However, median clet lip and palate can also
be seen without holoprosencephaly. In these cases, head size
and ocular diameters are normal. 90
Unusual Facial (Tessier) Clefts
Asymmetrical clets in unusual locations may be the result of
amniotic band syndrome or may fall into the Tessier clet
category (see Fig. 33.22). Tessier clets are rare, occurring in 1
to 5 per 100,000 live births. 91 hese clets are classiied by the
relationship of the clet to the mouth, nose, and eye sockets and
are numbered from 1 to 14, with the midline designated as 0.