A newborn has fused eyes and single nasal chamber & undeveloped callosum. What is the most probable diagnosis?

Holoprosencephaly: brain doesn't properly divide into right and left hemispheres. Associated with trisomy 13 (MC), trisomy 18, CHARGE syndrome Schizencephaly- characterized by abnormal slits or clefts in the cerebral hemispheres of the brain. Plagiocephaly- characterized by an asymmetrical distoion (flattening of one side) of the skull. Brachycephaly- result of premature synostosis of both coronal sutures.