What does MCA mean on an ultrasound?

MCA stands for “middle cerebral artery” and PSV stands for “peak systolic velocity.” MCA Dopplers are effectively an ultrasound that detects the speed blood is going through the babies’ brains.

What is abnormal MCA?

Abnormal MCA PI indicates fetal compensation by redistribution of fetal blood flow to the brain (‘brain sparing’) and shows progressive low-resistance flow with increasing diastolic flow. <5th percentile is abnormal.

What is middle cerebral artery in fetus?

Fetal middle cerebral arterial (MCA) Doppler assessment is an important part of assessing fetal cardiovascular distress, fetal anemia or fetal hypoxia. In the appropriate situation it is a very useful adjunct to umbilical artery Doppler assessment.

What is normal MCA PI?

In the normal cognitive group, we found that the mean value of right MCA PI was 0.87 (±0.15) and the left MCA PI was 0.86 (±0.18); while in the group with impaired cognitive, we found that the mean value of right MCA PI was 1.18 (±0.22) and left MCA PI was 1.21 (±0.17).

What is mild brain sparing effect?

Intrauterine growth restriction has been linked to infant behavioral problems. While typically only birth weight is examined, here the authors assessed fetal circulatory redistribution, also called the “brain-sparing effect,” which is a fetal adaptive reaction to placental insufficiency.

Is brain sparing good?

The term “brain-sparing” refers to relative protection of the brain as compared with other organs during fetal development, but this does not guarantee normal development after birth.

What is normal MCA?

What is MCA flow?

Doppler velocimetry of the middle cerebral artery (MCA) is a method to assess impedance/resistance to flow in the fetal brain circulation.

What is normal MCA PI in pregnancy?

Additionally, the ratio between the PI of the MCA and the PI of the umbilical artery was calculated. An MCA/umbilical artery PI ratio lower than 1.08 was considered a sign of fetal circulation redistribution or brain-sparing30.

When do you use the MCA Doppler?

MCA Doppler studies can be started as early as 18 weeks’ gestation but are not reliable after 35 weeks’ gestation. It has also been used to time the subsequent fetal transfusion and to diagnose anemia from multiple causes, such as in twin-twin transfusion.

Is brain sparing bad?

Potential Consequences of Prolonged Brain-Sparing Brain-sparing is in essence a protective mechanism under chronic hypoxaemia; however, prolonged brain-sparing may lead to an altered structure and function of the cerebral vasculature.

How are the arteries in the brain distributed?

Total cerebral blood flow (717±123 mL/min) was distributed to each side as follows: middle cerebral artery (MCA), 21% distal MCA, 6% anterior cerebral artery (ACA), 12%, distal ACA, 4% ophthalmic artery, 2% posterior cerebral artery (PCA), 8% and 20% to basilar artery. Deviating distributions were observed in subjects with ‘fetal’ PCA.

What is pulsatility index of middle cerebral artery?

Komwilaisak R, Saksiriwuttho P, Ratanasiri T et-al. Pulsatility index of the middle cerebral artery in normal fetuses. J Med Assoc Thai. 2011;87 Suppl 3: S34-7.

Why does the fetal MCA have a high resistance flow?

in the normal situation the fetal MCA has a high resistance flow which means there is minimal antegrade flow in fetal diastole in pathological states this can turn into a low resistance flow mainly as a result of the fetal head sparing theory

When to use a middle cerebral artery Doppler?

Abdel-fattah SA, Soothill PW, Carroll SG et-al. Middle cerebral artery Doppler for the prediction of fetal anaemia in cases without hydrops: a practical approach. Br J Radiol. 2002;75 (897): 726-30. Br J Radiol (full text) – Pubmed citation 7. Rodeck CH, Whittle MJ. Fetal medicine, basic science and clinical practice.