oval foramen


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o·val fo·ra·men

1. a large oval opening in the base of the greater wing of sphenoid bone, transmitting the mandibular division of the trigeminal nerve and a small meningeal artery;
2. valvular incompetence of the oval foramen of the heart; a condition contrasting with probe patency of the oval foramen in that the oval foramen valve has abnormal perforations in it, or is of insufficient size to afford adequate valvular action at the foramen ovale prenatally, or effect a complete closure postnatally.

oval foramen

1 an opening in the septum between the right and the left atria in the fetal heart. This opening provides a bypass for blood that would otherwise flow to the fetal lungs. Most of the blood from the inferior vena cava in the fetus flows through the foramen ovale into the left atrium. After birth the foramen ovale functionally closes when the newborn takes the first breath and full circulation through the lungs begins. Also called foramen ovale. See also ductus arteriosus.
2 an oval foramen situated laterally to the foramen rotundum of the sphenoid bone.

fo·ra·men o·va·le

, oval foramen (fōr-ā'mĕn ō-vā'lē, ō'văl) [TA]
1. The oval opening in the septum secundum in the embryonic and fetal heart; the persistent part of the septum primum acts as a valve for this interatrial communication during fetal life and normally postnatally becomes fused to the septum secundum to close it.
2. [TA] A large oval opening in the base of the greater wing of the sphenoid bone, transmitting the mandibular nerve and a small meningeal artery;
Synonym(s): Botallo foramen.