Not seeing a cerebral vermis at 33 weeks on ultrasound, and a slightly enlarged cisterna magna. Are these things I should be overly concerned about?

Need expert answer. I will refer this to perinatal and neonatal specialists for you. Thanks for asking an important question.
Type of Ultrasound? The findings of an us are often related to the type of us(probe sensitivity), chance, skill of technician & the physician reading the study.Assuming this is the higher level study, this could mean it could be there but wasn't found or it isn't there.Absence has a developmental impact and can be a recessively inherited trait.I would review the study with the dr or a geneticist & get more info.