Cryptorchidism, or failure of testicular descent, is a common human congenital abnormality with a multifactorial etiology that likely reflects the involvement of endocrine, environmental, and hereditary factors. Cryptorchidism can result in infertility and increases risk for testicular tumors. Testicular descent from abdomen to scrotum occurs in 2 distinct phases: the transabdominal phase and the inguinoscrotal phase (summary by Gorlov et al., 2002).

Abnormal outpouching or sac-like dilatation in the wall of an atery, vein or the heart.

In utero, the ductus arteriosus (DA) serves to divert ventricular output away from the lungs and toward the placenta by connecting the main pulmonary artery to the descending aorta. A patent ductus arteriosus (PDA) in the first 3 days of life is a physiologic shunt in healthy term and preterm newborn infants, and normally is substantially closed within about 24 hours after bith and completely closed after about three weeks. Failure of physiologcal closure is referred to a persistent or patent ductus arteriosus (PDA). Depending on the degree of left-to-right shunting, PDA can have clinical consequences.

Atrial septal defect (ASD) is a congenital abnormality of the interatrial septum that enables blood flow between the left and right atria via the interatrial septum.

The presence of chronic increased pressure in the systemic arterial system.

An abnormal localized widening (dilatation) of the thoracic aorta.

An abnormal widening (dilatation) of the common carotid artery.

An abnormal widening of the diameter of the pulmonary artery.

An abnormal localized widening (dilatation) of the aortic arch.

Pulmonary hypertension is defined mean pulmonary artery pressure of 25mmHg or more and pulmonary capillary wedge pressure of 15mmHg or less when measured by right heart catheterisation at rest and in a supine position.

The presence of a localized dilatation or ballooning of a cerebral artery.

Abnormally increased caliber of the left subclavian artery.

An abnormal widening (dilatation) of the brachiocephalic artery

An abnormality of the intestinal rotation and fixation that normally occurs during the development of the gut. This can lead to volvulus, or twisting of the intestine that causes obstruction and necrosis.

Reduced or inadequate peristalsis, with resultant slow passage of contents through the digestive tract.

Areas of brighter than expected signal on magnetic resonance imaging emanating from the cerebral white matter that surrounds the cerebral ventricles.

An abnormal gyral pattern characterized by abnormalities of sulcal depth or orientation.

Very rapid breathing.

Abnormal dilatation of the iris.