Inferior petrosal sinus
Encyclopedia
The inferior petrosal sinuses, within the human head, are beneath the brain and allow blood to drain from the center of the head.
They drain on either side inferiorly from the cavernous sinus
(beneath the brain) and join with the sigmoid sinus
to form the internal jugular vein
, which continues inferiorly to drain blood from the base of the skull. See diagram (at right): labeled under the brain as "S. PETROS. INF." (for Latin: sinus petrosus inferior).
The inferior petrosal sinus is situated in the inferior petrosal sulcus
, formed by the junction of the petrous part of the temporal bone with the basilar part of the occipital bone
.
It begins in the postero-inferior part of the cavernous sinus
and, passing through the anterior part of the jugular foramen
, ends in the superior bulb of the internal jugular vein
.
The inferior petrosal sinus receives the internal auditory veins
and also veins from the medulla oblongata
, pons
, and under surface of the cerebellum
.
They drain on either side inferiorly from the cavernous sinus
Cavernous sinus
The cavernous sinus , within the human head, is a large collection of thin-walled veins creating a cavity bordered by the temporal bone of the skull and the sphenoid bone, lateral to the sella turcica.-Contents:...
(beneath the brain) and join with the sigmoid sinus
Sigmoid sinus
The sigmoid sinuses , within the human head, are two areas beneath the brain which allow blood to drain inferiorly from the posterior center of the head. They drain from the transverse sinuses and converge with the inferior petrosal sinuses to form the internal jugular vein...
to form the internal jugular vein
Internal jugular vein
The two internal jugular veins collect the blood from the brain, the superficial parts of the face, and the neck.-Path:On both sides and at the base of the brain, the inferior petrosal sinus and the sigmoid sinus join to form the internal jugular vein...
, which continues inferiorly to drain blood from the base of the skull. See diagram (at right): labeled under the brain as "S. PETROS. INF." (for Latin: sinus petrosus inferior).
The inferior petrosal sinus is situated in the inferior petrosal sulcus
Inferior petrosal sulcus
The inferior petrosal sulcus is the groove containing the inferior petrosal sinus.The inferior petrosal sulcus is formed by the junction of the petrous part of the temporal bone of the skull with the basilar part of the occipital bone...
, formed by the junction of the petrous part of the temporal bone with the basilar part of the occipital bone
Occipital bone
The occipital bone, a saucer-shaped membrane bone situated at the back and lower part of the cranium, is trapezoidal in shape and curved on itself...
.
It begins in the postero-inferior part of the cavernous sinus
Cavernous sinus
The cavernous sinus , within the human head, is a large collection of thin-walled veins creating a cavity bordered by the temporal bone of the skull and the sphenoid bone, lateral to the sella turcica.-Contents:...
and, passing through the anterior part of the jugular foramen
Jugular foramen
The jugular foramen is a large aperture in the base of the skull. It is located behind the carotid canal and is formed in front by the petrous portion of the temporal, and behind by the occipital; it is generally larger on the right than on the left side....
, ends in the superior bulb of the internal jugular vein
Internal jugular vein
The two internal jugular veins collect the blood from the brain, the superficial parts of the face, and the neck.-Path:On both sides and at the base of the brain, the inferior petrosal sinus and the sigmoid sinus join to form the internal jugular vein...
.
The inferior petrosal sinus receives the internal auditory veins
Internal auditory veins
The veins of the vestibule and semicircular canals accompany the arteries, and, receiving those of the cochlea at the base of the modiolus, unite to form the internal auditory veins which end in the posterior part of the superior petrosal sinus or in the transverse sinus....
and also veins from the medulla oblongata
Medulla oblongata
The medulla oblongata is the lower half of the brainstem. In discussions of neurology and similar contexts where no ambiguity will result, it is often referred to as simply the medulla...
, pons
Pons
The pons is a structure located on the brain stem, named after the Latin word for "bridge" or the 16th-century Italian anatomist and surgeon Costanzo Varolio . It is superior to the medulla oblongata, inferior to the midbrain, and ventral to the cerebellum. In humans and other bipeds this means it...
, and under surface of the cerebellum
Cerebellum
The cerebellum is a region of the brain that plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language, and in regulating fear and pleasure responses, but its movement-related functions are the most solidly established...
.