Congenital malformations - Edocr

CHAPTER 51 CYSTIC HYGROMA 357
in late gestation or the postnatal period. Turner
Syndrome, 45 XO, is the most common chromosomal
abnormality associated with cystic hygromas
followed closely by Trisomy 21. It is estimated
that 5% of fetuses with a cystic hygroma may
have Down syndrome. 9 Other karyotypic abnormalities
and syndromes associated with cystic
hygromas are listed in Table 51-1.
EVALUATION
All fetuses with a prenatal diagnosis of cystic hygroma
should be evaluated by a detailed ultrasound
examination including echocardiogram
to evaluate for associated structural malformations
and signs of hydrops fetalis. A detailed
family and prenatal history, and karyotype
should be obtained. These pregnancies should
be followed closely to monitor progression of
cystic hygromas and hydrops fetalis irrespective
of karyotype results as there is no reliable
method to predict which hygroma will regress
or continue to progress. Initially it was considered
important to differentiate between septated and
nonseptated forms as the latter lesion may have
lower incidence of chromosomal abnormalities
and a better outcome as compared to the septated
cystic hygromas, but several subsequent
studies have failed to show any difference in
outcome. However, it has been suggested that
these nonseptated cystic hygroma should be
considered a variant of increased nuchal translucency
and are not included in some of the recent
studies of cystic hygroma.
If a diagnosis of cystic hygroma is first made
at birth, the evaluation of infant should include:
• Detailed family and prenatal history
• Complete physical examination for dysmorphic
features and signs of associated congenital
malformations
• Evaluation of the infant, parents, and the
siblings by a dysmorphologist/geneticist if
additional finings are noted
• Echocardiogram and abdominal ultrasound
to exclude structural anomalies and effusions
• Chest radiographs and/or computed tomography
(CT) to look for pleural effusion and
signs of mediastinal extension of hygroma
• Imaging of the lesion-preferably by magnetic
resonance imaging (MRI) but CT and
ultrasound can also be used
• Karyotype
MANAGEMENT AND PROGNOSIS
Airway management at birth is crucial particularly
in cases with a large cervical lesion. The
establishment of airway access while placental
perfusion to the fetus is maintained as in Exutero
Intrapartum Treatment (EXIT) or Operation
On Placental Support (OOPS) procedures,
should be considered in these cases. Surgical
resection is the treatment of choice. Since this is
a benign lesion, complete and total resection of
the lesion is not necessary and sometimes not
possible. Aggressive resection may lead to injury
to surrounding tissues and neurovascular
structures and may contribute to poor outcome
and long-term morbidities.
Alternative methods of treatment include injection
of sclerosing agents, aspiration, laser
diathermy, and radiation. None of these therapies
have been efficacious but use of a newer
sclerosing agent, OK-432 appears promising.
OK-432, Picibanil, is derived from a low-virulent
strain of Streptococcus pyogenes and requires
several intralesional injections but appears to be
a promising alternative to surgery. Spontaneous
resolution of these lesions overtime has been
reported and observation should be considered
in absence of an urgent indication for intervention.
Residual or recurrent hygroma is a frequent
problem and their incidence varies with treatment
modality and the site of lesion.
PROGNOSIS OF EARLY
GESTATION CYSTIC HYGROMAS
Cystic hygromas have historically been associated
with a grim prognosis when diagnosed in