Blood supply to the basal ganglia

Tuesday, November 21, 2017

The basal ganglia, which are grey structures at the base of the brain, are supplied by the lenticulostriate arteries, also called anterolateral central arteries. These oxygen-rich blood vessels arise from the M1 segment of the middle cerebral artery, which, in turn, originate from the internal carotid artery. They are between three and five branches that come off the middle cerebral artery and run upwards in each cerebral hemisphere.

Foramen transversarium

Wednesday, November 15, 2017

The foramen transversarium, or transverse foramen, is one of two orifices that are found in the transverse processes on each side of the seven cervical vertebrae (neck region). The function of these small openings in the vertebrae processes is to lodge and protect each of the two vertabral arteries, which run through them upwards until they enter the skull through the foramen magnum. The vertabral arteries arise from the subclavian arteries and join together in the base of the skull to form the basilar artery.

Transverse foramen in cervical vertebra

Transverse foramina lodging the one of the vertebral arteries in the neck.

Foramen spinosum

Thursday, October 19, 2017

The foramen spinosum is a paired orifice, which is found on the greater wing of the sphenoid bone, one on each side of the base of the skull. In other words, it is located anteriorly to the sphenoid bone spine. Function: the foramen spinosum serves as a passageway to the nervus spinosus, which is the meningeal branch of the mandibular nerve, and to the middle meningeal artery. The nervus spinosus innervates the meninges, and the middle meningeal artery supplies the dura mater.

Location of the foramen spinosum in the base of the human skull
image from usf edu

Zygomatic arteries

Wednesday, October 18, 2017

The zygomatic arteries are oxygen-rich blood vessels that originate from the lacrimal artery, which, in turn, arises from the ophthalmic artery. They are usually two branches that come off as lateral projections of the lacrimal. Then they further fork into smaller caliber vessels. Function: they supply the zygomatic bone and other structures.

Blood supply to the frontal lobe

Friday, October 6, 2017

The human brain frontal lobe is supplied by the middle cerebral and anterior cerebral arteries. Both of them are branches of the internal carotid artery. The pre-central, the pars triangularis, the inferior frontal, the middle frontal, and the superior frontal gyrus of the frontal lobe receive oxygen-rich blood from the pre-rolandic artery and the pre-frontal arteries, all of which come off the M4 or cortical segment of the middle cerebral artery.

The orbitofrontal cortex of the frontal lobe is supplied by the lateral frontobasal artery, which is also a branch of M4 segment of the middle cerebral artery. Meanwhile, the orbitofrontal and the frontopolar artery, which arise from the anterior cerebral artery, supply also the orbitofrontal and other regions of the pre-frontal lobe. The pericallosal artery of the anterior cerebral artery supply the medial (internal) surface of the frontal lobe, the area that partially surrounds the corpus callosum.

Lacrimal artery

Tuesday, October 3, 2017

The lacrimal artery is an oxygen-rich blood vessel which arises from the ophthalmic artery. It runs parallel and above the lateral rectus muscle in the orbit. It supplies the lacrimal gland with oxygenated blood. Branches: zygomatic arteries.

Blood supply to the brain

Saturday, September 30, 2017

The blood supply to the human brain is carried out by two main arteries; the internal carotid artery, which is a paired blood vessel, and the basilar artery. Both arteries carried oxygenated blood pumped by the heart left ventricle during the systole.

The internal carotid artery arises from the common carotid artery, on each side of the neck, carrying up about 60% of the oxygenated blood volume the brain needs. Having given off the ophthalmic artery as the first branch, it divides into the anterior cerebral, middle cerebral, and posterior communicating artery, forming the circle of Willis at the base of the brain. The middle cerebral artery is the most important one because of the large volume of oxygenated blood it carries, supplying not only the basal ganglia, but also a large portion the cerebral cortex.

The basilar artery is formed by the union of the right and left vertebral arteries in the posterior part of the skull, at the base of the encephalon. Having given off vital branches, such as the pontine, which supply the pons, and the cerebellar arteries, it forks into the two posterior cerebral arteries, which join the circle of Willis.