petrosal

Mammals have an elongated cochleal canal and a promontorium on the petrosal, features involved in improving both high-frequency hearing and the acoustic isolation of the inner ear.

Archive 2006-01-01 Darren Naish 2006

On the lateral margins of this surface are faint grooves for the inferior petrosal sinuses.

II. Osteology. 5a. The Cranial Bones. 1. The Occipital Bone 1918

The inferior cerebellar veins (vv. cerebelli inferiores) of large size, end in the transverse, superior petrosal, and occipital sinuses.

VII. The Veins. 3b. 4. The Veins of the Brain 1918

At the base of the lateral pterygoid plate is the foramen ovale, for the transmission of the mandibular nerve, the accessory meningeal artery, and sometimes the lesser superficial petrosal nerve; behind this are the foramen spinosum which transmits the middle meningeal vessels, and the prominent spina angularis (sphenoidal spine), which gives attachment to the sphenomandibular ligament and the Tensor veli palatini.

II. Osteology. 5c. The Exterior of the Skull 1918

Those on the orbital surface of the frontal lobe join the superior cerebral veins, and through these open into the superior sagittal sinus; those of the temporal lobe anastomose with the middle cerebral and basal veins, and join the cavernous, sphenoparietal, and superior petrosal sinuses.

VII. The Veins. 3b. 4. The Veins of the Brain 1918

The lesser superficial petrosal nerve sometimes passes through a special canal (canaliculus innominatus of Arnold) situated medial to the foramen spinosum.

II. Osteology. 5a. 5. The Sphenoid Bone 1918

Behind and lateral to this is the foramen ovale, for the transmission of the mandibular nerve, the accessory meningeal artery, and sometimes the lesser superficial petrosal nerve.

II. Osteology. 5a. 5. The Sphenoid Bone 1918

The superior cerebellar veins (vv. cerebelli superiores) pass partly forward and medialward, across the superior vermis, to end in the straight sinus and the internal cerebral veins, partly lateralward to the transverse and superior petrosal sinuses.

VII. The Veins. 3b. 4. The Veins of the Brain 1918

On either side of the dorsum sellæ is a notch for the passage of the abducent nerve, and below the notch a sharp process, the petrosal process, which articulates with the apex of the petrous portion of the temporal bone, and forms the medial boundary of the foramen lacerum.

II. Osteology. 5a. 5. The Sphenoid Bone 1918

This plexus gives off: (1) the lesser superficial petrosal nerve; (2) a branch to join the greater superficial petrosal nerve; and (3) branches to the tympanic cavity, all of which will be described in connection with the anatomy of the middle ear.

IX. Neurology. 5i. The Glossopharyngeal Nerve 1918