Foramen rotundum

Foramen rotundum of Sphenoid
Sphenoid bone. Upper surface. (Foramen rotundum labeled at center left)
Base of the skull. Upper surface. Sphenoid is yellow, and arrows indicate the foramen rotundum.)
Details
Identifiers
Latin	foramen rotundum ossis sphenoidalis
TA	A02.1.05.035
FMA	53154
Anatomical terms of bone []

The foramen rotundum is a circular hole in the sphenoid bone that connects the middle cranial fossa and the pterygopalatine fossa.

The foramen rotundum is one of the several circular apertures (the foramina) located in the base of the skull, in the anterior and medial part of the sphenoid bone.

The mean area of the foramina rotunda is not considerable, which may suggest that they play a minor role in the dynamics of blood circulation in the venous system of the head.

The foramen rotundum evolves in shape throughout the fetal period, and from birth to adolescence. It achieves a perfect ring-shaped formation in the fetus after the 4th fetal month. It is mostly oval-shaped in the fetal period, and round-shaped after birth (generally speaking). After birth, the rotundum is about 2.5 mm and in 15- to 17-year olds about 3 mm in length. The average diameter of the foramen rotundum in adults is 3.55 mm. This was according to a developmental study published in The Hokkaido Journal of Medical Science on the foramen ovale, the foramen spinosum and the foramen rotundum, and according to a study about the postnatal enlargement of the foramina rotundum, ovale and spinosum and their topographical changes published in the Anatomischer Anzeiger.

The maxillary branch (V₂) of the trigeminal nerve (CN V) passes through and exits the skull via the pterygopalatine fossa and the foramen rotundum.

Foramen is the Latin term designating a hole-like opening. It derives from the Latin forare meaning to bore or perforate. Here, the opening is round as indicated by the Latin rotundum meaning round.

Horizontal section of nasal and orbital cavities.

Medial wall of left orbit. The lowest label among those at upper right of the image reads Probe in foramen rotundum.

Foramen rotundum

Labeled image of interior skull base.

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)