Three children with septo-optic dysplasia (SOD) and an associated malformation of cortical organization are reported from McGill University and the Montreal Children’s Hospital, Quebec, Canada. Case 1, a 10-year-old girl, presenting with left hemiparesis, deafness and short stature, was microcephalic, developmentally delayed, and had a growth hormone deficiency. MRI showed an absent septum pellucidum, absent cochlea, hypoplasia of the optic chiasm, and right sylvian polymicrogyria. Case 2, a 4-year-old boy, had absent visual fixation and global developmental delay. MRI showed absent septum pellucidum, optic chiasm hypoplasia, and focal polymicrogyria. Case 3, a 4-year-old girl, had global developmental delay, spastic quadriparesis, and facial diplegia with dysarthria and drooling. MRI showed absent septum pellucidum, optic chiasm hypoplasia, and right open-lipped schizencephaly. The term SOD-Plus is proposed, to extend the SOD-schizencephaly syndrome to include other associated cortical malformations. 
COMMENT. Previous reports of septo-optic dysplasia (SOD) have emphasized the common association with schizencephaly, and the occurrence of alternative or additional cortical malformations may be under-recognized. SOD presenting with global developmental delay or spastic motor deficits should prompt screening with MRI to identify polymicrogyria and other cortical malformations. The most common clinical presentation of SOD includes visual impairment and signs of pituitary hypofunction. The MRI abnormalities may not be limited to schizencephaly.