Septo-optic dysplasia

Septo-optic dysplasia (SOD) or de Morsier's syndrome is a rare congenital disorder characterized by a classic triad of: (a) optic nerve hypoplasia, (b) agenesis of septum pellucidum and corpus callosum, and (c) hypoplasia of the hypothalamic-pituitary axis. This chapter will outline the key information regarding the etiology and epidemiology of this syndrome with a focus on its comprehensive management. Particular attention will be paid to the diagnostic stage and the most relevant differential diagnosis, before moving to the complexities of its treatment. In fact, although SOD is not curable, many aspects of this syndrome can be improved through a tailored multidisciplinary approach consisting in hormonal replacement, corrective ophthalmological surgery, management of epileptic seizures, and active neuropsychological support.

The central diabetes insipidus associated with septo-optic dysplasia (de Morsier syndrome)

INTRODUCTION

Septo-optic dysplasia (SOD) is a rare congenital heterogeneous malformation with postulated genetic and environmental etiology. Septo-optic dysplasia is characterized by classic triad: optic nerve hypoplasia, midline brain malformation and hypothalamic-pituitary endocrine deficiencies. The most common hormonal deficiencies affect growth hormone and gonadotropin but it can also be lower levels of the other hormones. The rarest form of hormone deficiency is the deficiency of the antidiuretic hormone.

CASE REPORT

The boy was born in 39th week of pregnancy in general good condition. Weakened suction reflex and spitting resulted in substantial difficulties with breastfeeding. After transfontanelle ultrasonography central nervous system defect was suspected. In the 5th month of life MRI confirmed septo-optic dysplasia on the basis of anterior genu of corpus callosum and septum pellucidum agenesis, both optic nerves and optic chiasm hypoplasia, pachygyria and polimicrogyria of the right frontoparietal cortex. Neurological examination revealed axial laxity, psychomotor development delay, difficulties in keeping eyes fixed as well as rotary and horizontal nystagmus. At the age of 3 years he underwent the endocrinological consultation due to polydipsia and polyuria. The tests revealed lower urine specific gravity tests results, therefore diabetes insipidus was diagnosed. The boy still receives desmopressin and there are no signs of central diabetes insipidus. Currently, the boy is under a multi-disciplinary medical care.

CONCLUSIONS

The attention should be focussed on early diagnosis, mutli-specialized care and treatment SOD. Hypopituitarism ranges from isolated to multiple hormone deficits, with diabetes insipidus in a minority. Although rare, SOD is an important cause of congenital hypopituitarism and should be considered in all children with midline defects and optic nerve hyploplasia.

Septo-optic dysplasia

Septo-optic dysplasia is a rare disorder characterized by optic nerve hypoplasia; midline developmental defects including agenesis of the septum pellucidum, thinning or absence of the corpus callosum, or both; and deficiencies of pituitary hormones. The majority of cases are sporadic but rare familial cases occur. The clinical manifestations include poor visual function in one or both eyes, developmental delay, seizures, sleep disturbances, and precocious puberty. A life-long multidisciplinary approach is crucial in the management of these patients to optimize their growth and development and to help them lead as normal lives as possible.

Septooptic dysplasia

The term septooptic dysplasia was coined in 1956 by de Morsier, who pointed out the association of optic nerve hypoplasia and absence of the septum pellucidum. Patients with this condition may present with clinical features of hypopituitarism, decreased visual acuity and neurodevelopmental disabilities that lead to this diagnosis. The case that is presented here is unusual in that this patient was initially diagnosed as having low tension glaucoma during a routine screening examination and was treated for glaucoma for over a year before he was discovered to have septooptic dysplasia, also known as de Morsier's syndrome.