fetal middle cerebral artery peak systolic velocity
Doppler ultrasound measurement used to detect fetal anemia by assessing blood flow velocity in the brain's middle cerebral artery.
Full Definition
Fetal middle cerebral artery peak systolic velocity (MCA-PSV) is a non-invasive Doppler ultrasound measurement that assesses the maximum blood flow velocity in the fetal middle cerebral artery during systole. This measurement is primarily used to detect fetal anemia, as anemic fetuses demonstrate increased cardiac output and higher blood flow velocities. The technique is particularly valuable in managing pregnancies complicated by red cell alloimmunization, parvovirus infection, or twin-to-twin transfusion syndrome. Values are plotted against gestational age-specific reference ranges, with elevations above 1.5 multiples of the median suggesting moderate to severe fetal anemia.
Usage
Usage note: Commonly abbreviated as MCA-PSV. Values must be interpreted with gestational age-specific nomograms.
In Context
- "The MCA-PSV measured 1.8 multiples of the median, indicating severe fetal anemia requiring urgent intervention." — Ultrasound report
- "Serial monitoring of fetal middle cerebral artery peak systolic velocity will guide timing of intrauterine transfusion." — Management plan