Obgyn Key

KEY POINTS Print Section Listen Key Points The vein of Galen is a single, midline structure formed by the convergence of the two internal cerebral veins and the basal veins…

KEY POINTS Print Section Listen Key Points There are two main forms of porencephaly: (1) developmental porencephaly and (2) congenital encephaloclastic porencephaly. The first type represents primary failure of neuronal…

KEY POINTS Print Section Listen Key Points Fetal intracranial hemorrhage is generally diagnosed in the late second trimester as an asymmetric echogenic mass within the ventricles, mostly associated with some…

KEY POINTS Print Section Listen Key Points Microcephaly is characterized by a smaller than normal head circumference. A head circumference measurement of 3 SD below the mean gives a clinically…

KEY POINTS Print Section Listen Key Points A complex brain malformation characterized by the forebrain failing to cleave into two hemispheres, a process that is usually completed by 5 weeks….

KEY POINTS Print Section Listen Key Points Macrocephaly is defined as a head circumference greater than three standard deviations (SDs) above the mean for age and sex. This disorder is…

KEY POINTS Print Section Listen Key Points Hydrocephalus is usually due to obstruction of CSF flow, either within (noncommunicating hydrocephalus) or outside (communicating hydrocephalus) the ventricles. Ventriculomegaly simply refers to…

KEY POINTS Print Section Listen Key Points Rare fetal anomaly that is incompatible with survival. Bones of the cranial vault are absent but facial structures and skull base are preserved….

KEY POINTS Print Section Listen Key Points Encephalocele is a rare defect of the cranial vault, which may contain meninges only, or also neural tissue. Most cases in Caucasian populations…

KEY POINTS Print Section Listen Key Points Dandy–Walker malformation refers to the combination of hypoplasia of the cerebellar vermis, cystic dilation of the fourth ventricle communicating with the cisterna magna,…