Qualitative analysis of Doppler assessment used for surveillance of alloimmunized individuals

Objectives: To summarize image quality variables for alloimmunized women at risk for fetal anemia. To investigate the association between image quality with the highest and median middle cerebral artery peak systolic velocity (MCA-PSV) at the last visit and fetal anemia based on hemoglobin.

Study design: This study was a qualitative retrospective analysis of 192 Doppler ultrasound images used in the detection of fetal anemia in 26 alloimmunized women seen in a Minneapolis hospital over the past 3 years. Images were graded on seven criteria found in literature.

Results: Of the images analyzed, 23 (12.0%) of the 192 met all seven image quality criteria. Using the highest MCA-PSV value, the sensitivity, and specificity were 55.6% and 94.1%, respectively. Using the median MCA-PSV value, the sensitivity, and specificity were 44.4% and 94.1%, respectively.

Conclusions: Only a minority of Doppler images meet all suggested image criteria. This could negatively impact the accuracy of the MCA-PSV measurements as indicated by the decreased sensitivity in our evaluations.