Sonographic Development of the Pericallosal Vascularization in the First and Early Second Trimester of Pregnancy.

The pericallosal artery and its branches can be identified and measured from 11 weeks on, and the pericallosal artery takes its characteristic course. A defective course or an abnormal biometry of the pericallosal artery could be an early sonographic marker of abnormal development of the corpus callosum.