 Good afternoon everyone. I am Dr. Sneha Santoshrati. My topic for paper presentation is prenatal ultrasound evaluation of retrology of phallid. Ames. We emphasize the ultrasound findings of retrology of phallid, early detection of retrology of phallid, evaluation of other associated pathologies and congenital defects in fetus by ultrasound. Introduction. Toph is a congenital heart defect classically described like a four anatomical heart abnormalities. It is most frequent cyanotic heart defect and the most common cause of blue baby syndrome due to right to left shunt. Retrology of phallid has four classic features, VSD and overriding outer, pulmonary artery stenosis and right ventricular hypertrophy. The VSD associated with retrology of phallid is usually sub-outic and is due to overriding of outer. Toph is caused by unequal division of the conness resulting from anterior displacement of the trunco-conal system. Prevalence of retrology of phallid is 3 to 7% of congenital heart defects. The main reason for suspecting Toph is failure to demonstrate the normal crossing of great vessels at the base of the heart. Methods. Retrospective study was conducted at ANCOPD in our mother and child care hospital within a span of 6 months. Out of 15 cases suspected for congenital cardiac anomalies, 10 cases of Toph were recognized by ultrasound between 20 to 28 weeks of gestation. GE logic P5 ultrasound machine was used. Strict adherence to PCP&T guidelines and proper written consent was ensured. In each case, a four chamber view to assess abnormalities of atria and ventricles and a base view to demonstrate crossing of great vessels were performed. Results. Out of 15 cases suspected for congenital cardiac anomalies, 10 cases of tetralogy of phallid were recognized by ultrasound between 20 to 28 weeks of gestation. Based on the small series, prenatal sonographic findings suggested of Toph may be summarized as follows. A large autic root which is the most common prenatal sonographic finding. A small pulmonary artery or stenosis of the right ventricular outflow tract. A ventricular septal defect in the outlet portion of the septum. An overriding outer which is best seen in the long axis view and a right ventricular hypertrophy. The most common characteristic were ventricular septal defect and a large autic root. Other associated findings like hydropsvitalis and polyhydromoids were also detected in three cases. Discussion. Toph is due to an embryological development of the heart in which an unequal conotrunkal division results in a small pulmonary artery and a great autic artery. The incomplete embryologic rotational process of the conotrunkal septum explains a lack of alignment of the septum with the interventricular septum and tetralogy of phallid. The incomplete rotational process of the autic artery explains its extra position, its overriding location above the interventricular septum and its relationship with the right ventricular. The pulmonary artery remains in an anterior position in relation to the outer. Now this differentiates Toph from complete transposition of the great vessels where the position of the pulmonary and autic arteries is inverted. Under normal circumstances, one septum is continuous with the other. The abnormal alignment process produces a defect of tissue between the septum causing the interventricular communication. On ultrasound examination, a perimembranous VSD is noted. Myelistinotic right ventricular outflow tract is noted. Right ventricular hypertrophy is not noted in the mid-second trimester but it develops after birth. Inverse relationship between the size of the ascending outer and pulmonary artery. A large autic root is an important diagnostic clue. Colour Doppler may demonstrate a reverse flow in the ductus arteriosus to the main pulmonary artery. In pulmonary stenosis and atresia, high velocity and turbulence is noted. Doppler studies demonstrate increased peak velocities in the pulmonary artery due to the right ventricular outflow tract obstruction. It may also demonstrate no flow in the pulmonary artery if complete atresia is present. The overhiding of outer with blood entering from both ventricles into the outer is visible in the form of a five-shape image in colour Doppler during systolic phase. Other findings such as hydropsvitalis or polyhydromneus may also be helpful especially in the case of this plastic pulmonary valves. In the following images, in the first image, there is a VSD with a large autic root. In the second and third image, there is mildly synotic right ventricular outflow tract with high velocity and turbulence noted. In the fourth image, there is a VSD with overhiding of outer. And in the fifth image, in the three-vessel view, only two vessels are seen. Narrow pulmonary artery is noted. Conclusion. The top is the most common congenital synotic heart disease. The antenatal diagnosis can be to look for other associated abnormalities or chromosomal aberrations and allow us to determine a therapeutic strategy. Thank you.