In humans In humans, the stapedial artery is normally present in the
fetus where it connects what is to become the
external and
internal carotid arteries. Part of the carotid artery system, it originates from the dorsal branch of
aortic arch. Its superior supraorbital branch becomes the
middle meningeal artery, while its infraorbital and mandibular branches fuses with the external carotid artery and later become the
internal maxillary artery. Its trunk atrophies and is replaced by branches from the external carotid artery. In rare cases, the embryonic structure is still present after birth in which case it is referred to as a
persistent stapedial artery (PSA).
In other mammals Structures homologous to the stapedial artery in humans and other
primates can be derived from a primitive, hypothetical pattern similar to that found in primitive rodents: the stapedial artery enters the
middle cranial fossa and splits into the anterior and inferior divisions of the superior ramus and the inferior ramus. The inferior ramus has been lost in
strepsirhines while the stem of the stapedial artery has been reduced in
haplorhines. ==Notes==