Abstract
Septooptic dysplasia (SOD) is a rare heterogeneous disorder characterized by optic nerve hypoplasia, midline forebrain abnormalities such as agenesis of the corpus callosum and absence of the cavum septi pellucidi, and pituitary hypoplasia with consequent panhypopituitarism. Diagnosis of SOD requires the presence of any two of the classic features: optic nerve hypoplasia, midline forebrain abnormalities, or pituitary hypoplasia. The etiology of SOD is uncertain but may be the result of mutations in the homeobox gene HESX1 or a possible autosomal recessive inheritance. Sporadic cases are thought to be the result of vascular disruption, exposure to teratogens such as valproic acid and ethanol, viral infections such as cytomegalovirus, or maternal drug abuse with cocaine and amphetamines. Clinical manifestation is variable and depends on the extent of the anatomic defects and the degree of pituitary involvement. Most affected individuals exhibit neurodevelopmental disability, visual deficits, and seizures. The classic ultrasound finding is absence of the cavum septi pellucidi, with communication between the two frontal horns across the midline. The corpus callosum may be present, thinned, or absent. Mild ventriculomegaly is commonly seen. No special obstetric management is required for patients carrying a fetus with suspected SOD. Genetic amniocentesis may be helpful to rule out aneuploidy and to facilitate parental counseling. Termination of pregnancy is an option when the diagnosis is certain and made early. Neonatology or pediatric neurology consultation is beneficial to prepare parents regarding follow-up in the neonatal period and long-term prognosis.
Original language | English |
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Title of host publication | Obstetric Imaging |
Subtitle of host publication | Fetal Diagnosis and Care, 2nd Edition |
Publisher | Elsevier |
Pages | 172-174.e1 |
ISBN (Electronic) | 9780323445481 |
DOIs | |
State | Published - Jan 1 2017 |
Keywords
- Absent cavum septi pellucidi
- Agenesis of the corpus callosum
- Midline forebrain abnormalities
- Optic nerve hypoplasia
- Pituitary hypoplasia
- Ventriculomegaly