Early visualization and measurement of the pericallosal artery: an indirect sign of corpus callosum development.

Objectives: The purpose of this study was to evaluate the feasibility of visualization and measurement of the pericallosal artery during early stages of gestation.

Methods: The study group comprised 80 pregnant women between 12 and 21 weeks' gestation who attended our ultrasound unit. Transabdominal or transvaginal sonography was performed to obtain the optimal angle of a midsagittal section. High-definition flow power Doppler imaging was used to visualize the pericallosal artery. In a sagittal plane, the lengths of the pericallosal artery were measured using a straight line to connect the most anterior and posterior points. All patients were reexamined at a later stage of pregnancy to verify the existence of the corpus callosum and pericallosal artery.

Results: Visualization of the pericallosal artery was evident in 71 fetuses, in all of whom the biparietal diameter was greater than 20 mm. We were able to verify normal anatomy and the existence of the pericallosal artery in these fetuses between 30 and 32 weeks' gestation. A positive linear association was found between the length of the pericallosal artery and the gestational age (R(2) = 0.95) and the biparietal diameter at each gestational age (R(2) = 0.99).

Conclusions: Our data show that it is feasible to visualize and measure the pericallosal artery from an early stage of gestation, and this measurement could be an indirect indication of normal corpus callosum development.