The thin membrane located at the middle of the brain is known as septum pellucidum (SP). Children who suffer from the absence of this membrane and have other abnormalities like pituitary deficiencies and abnormal development of optic disk have a disorder known as septo-optic dysplasia.
The absence of septum pellucidum alone is not a disorder but, it is a characteristic noted in children with septo-optic dysplasia.
As mentioned, the absence of septum pellucidum alone does not qualify as a disorder. However, when it becomes a part of septo-optic dysplasia the prognosis may vary according to the presence and severity of associated symptoms.
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