Using two-dimensional and Doppler echoencephalography, we examined ventricularsize and pulsatility index (PI) of 26 infants with various congenital cardiac diseases. Four cases with large ventricles showed a malformed syndrome. Two cases had chromosomal abnormalities, one case was a post-operative patient. The width of ventricles out particular episodes were normal. We believed the enlargement of ventricles in the four cases was due to those elements except cardiac disease. The cases with high PI were a Co/Ao, a Co/Ao+PDA, four TGAs, a DORV+PDA, a truncus arteriosus, a tricuspid atresia+PDA, and HLHS. All cases had left to right shunt in the great artery levels. The case of low P1 was ECD which had severe cardiac failure. Pl of other cases were within normal limits. The change of systemic flow pattern influences cerebral flow pattern. We must consider the systemic flow pattern when we evaluate PI of the cerebral arteries.
