Citation, DOI & article data
Septo-optic dysplasia (SOD), also known as de Morsier syndrome, is a condition characterized by optic nerve hypoplasia and absence of the septum pellucidum and, in two-thirds of patients hypothalamic-pituitary dysfunction. It is best thought of as being part of the holoprosencephaly spectrum (see classification system for midline malformations).
Septo-optic dysplasia has an estimated prevalence of ~1:50,000. There is no recognized gender predilection.
A number of risk factors have been identified 8,9:
drug and alcohol abuse
Clinical presentation of septo-optic dysplasia is varied and mostly dependent on whether or not it is associated with schizencephaly (~50% of cases). This association is used to define two forms of the condition 1,8:
not associated with schizencephaly
visual apparatus more severely affected
hypothalamic-pituitary dysfunction present in 60-80% of patients 6,8
may present as hypoglycemia in the neonatal period 6
associated with schizencephaly
In addition, a number of other associations are recognized including:
The abnormality develops during 4th-6th weeks of gestation, during early forebrain development. The exact etiology is unknown, with an underlying genetic defect currently accounting for <1% of cases 9.
All imaging modalities that can visualize the septum pellucidum (ultrasound, CT and MRI) will detect its absence in septo-optic dysplasia. Some additional modality dependent features may also be visible.
In addition to enlarged lateral ventricles with an absent septum pellucidum, CT may demonstrate small optic apparatus (best seen with volumetric scanning and coronal reformats) and associated small bony optic foramina.
MRI is the modality of choice for assessing septo-optic dysplasia.
may show a "point down" appearance of the lateral ventricular frontal horns on coronal images
absent septum pellucidum
hypoplastic pituitary stalk
hypoplastic optic chiasm/optic nerves and globes
Treatment and prognosis
The management of septo-optic dysplasia requires a multidisciplinary team to assess and treat for hormonal imbalance, loss of vision, autism and obesity 9.
History and etymology
Septo-optic dysplasia was first described by George de Morsier (1894-1982), Swiss neurologist in 1956 6,7.
may not be able to be differentiated 8
cerebral anterior artery will have its course shifted anteriorly in lobar holoprosencephaly (sign described on prenatal ultrasound also, midline sagittal view with color Doppler)
optic chiasm is not expected to be hypoplastic
- 1. Sener R. Septo-Optic Dysplasia Associated with Cerebral Cortical Dysplasia (Cortico-Septo-Optic Dysplasia). J Neuroradiol. 1996;23(4):245-7. - Pubmed
- 2. Tien R, Felsberg G, Krishnan R, Heinz E. MR Imaging of Diseases of the Limbic System. AJR Am J Roentgenol. 1994;163(3):657-65. doi:10.2214/ajr.163.3.8079864 - Pubmed
- 3. Barkovich A, Fram E, Norman D. Septo-Optic Dysplasia: MR Imaging. Radiology. 1989;171(1):189-92. doi:10.1148/radiology.171.1.2928524 - Pubmed
- 4. Levine L, Bhatti M, Mancuso A. Septo-Optic Dysplasia with Olfactory Tract and Bulb Hypoplasia. J AAPOS. 2001;5(6):398-9. doi:10.1067/mpa.2001.118869 - Pubmed
- 5. Osborn R. Schizencephaly and Septo-Optic Dysplasia: Separate Entities. Pediatr Radiol. 1989;20(1-2):137. doi:10.1007/BF02010665 - Pubmed
- 6. Harvey B. Sarnat, Paolo Curatolo. Malformations of the Nervous System. (2008) ISBN: 9780444518965 - Google Books
- 7. Michael Jeffrey Aminoff, Robert B. Daroff. Encyclopedia of the Neurological Sciences. (2014) ISBN: 9780123851574 - Google Books
- 8. Mauricio Castillo. Neuroradiology Companion. (2006) ISBN: 9780781779494 - Google Books
- 9. Webb E & Dattani M. Septo-Optic Dysplasia. Eur J Hum Genet. 2010;18(4):393-7. doi:10.1038/ejhg.2009.125 - Pubmed