SC Phocomelia Syndrome
SC Phocomelia syndrome is characterized by facial and limb abnormalities.
Limb abnormalities consist of tetraphocomelia and abnormal thumb position.
The craniofacial features include sparse hair, hypertelorism, exophthalmus,
coloboma of the eyelids, corneal opacity, cataracts, and dysplastic ears.
Prominent clitoris or penis has been reported. Other systemic abnormalities,
especially kidney abnormalities, may be present. About 80% of patients
with Roberts SC Phocomelia syndrome have premature separation of centromeric
heterochromatin in many chromosomes.
of Miller-Dieker syndrome is considered in the presence of a peculiar
facies and typical findings on MRI of the brain. A most characteristic
feature (although not always present nor specific for this entity) is
furrowing of the forehead. Furrowing is especially prominent when crying.
Magnetic resonance imaging of the brain shows a smooth cerebral surface,
large vertical Sylvian fissures, and hypoplasia of the operculum. These
abnormalities give the brain a “figure 8” configuration. The cerebral
cortex is thick. Electroencephalogram typically shows a burst-suppression
or hypsarhythmic pattern. Genetic diagnosis is available. Some patients
will show abnormalities on prometaphase chromosome study. These abnormalities
consist of ring chromosome or terminal deletion of chromosome 17. Most
patients with Miller-Dieker syndrome have a deletion at 17p13.3 that can
be demonstrated with the use of fluorescent in situ hybridization.