Difference between near-field and far-field of middle cerebral artery doppler pulsatility index and peak systolic velocity: a prospective study

Abstract

Objective: We purposed to investigate the difference between near-field and far-field of PI (pulsatility index) and peak systolic velocity (PSV) of the middle cerebral artery (MCA) that are important in the management of fetal growth restriction and fetal anemia. Methods: This prospective study was conducted with 130 single uncomplicated pregnancies. Doppler was applied to near-and far-field of proximal MCA while PSV and PI were recorded and compared between two sides as well as according to body mass index (BMI) and gestational weeks of participants. Results: There was no statistically significant difference between near and far-fields of MCA PI (P = 0.75). However, a statistically significant difference in PSV was observed (P = 0.03), and this was especially noticeable in women with normal BMI (P = 0.009). On the other hand, there was no difference between MCA PI or PSV in women with a BMI higher than 25. Also, no significant difference was observed between groups, which were subcategorized according to gestational weeks. Conclusions: Our data suggest that the far-field PSV values may be higher than near-field MCA PSV values; sonographers should bear in mind that while far and near-field PSV can differ, conversely MCA PI can safely be assessed from both the near and far-fields of MCA in case of technical difficulty.

Keywords

• doppler ultrasound
• middle cerebral artery
• peak systolic velocity
• pulsatility index