Fetal cardiothoracic circumference ratio

Fetal cardiothoracic (C/T) circumference ratio is a parameter than can be used in assessment of fetal cardiac and thoracic/chest wall anomalies. It is the ratio of the cardiac circumference to the thoracic circumference and may be easily measured on fetal ultrasound/echocardiography.

Radiographic features

Ultrasound/echocardiography

The C/T circumference ratio should be always <0.5 throughout gestation. It slowly increases throughout gestation:

  • ~11 weeks: 0.38
  • ~17-20 weeks: 0.45
  • term: 0.5

Increased C/T circumference ratios can be observed with either cardiac or thoracic pathology:

See also

Siehe auch: