Middle Meningeal Artery Anatomy
Middle Meningeal Artery Anatomy
Middle Meningeal Artery: The intermediate meningeal artery (Latin: arteria meningea media) is customarily the third branch of the first excerpt of the maxillary artery, one of the two terminal branches of the external carotid artery. After consequence off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to supply the dura mater the outer meningeal thickness, and the calvaria. The middle meningeal artery is the enormousest of the three (paired) arteries that supply the meninges, the others being the anterior meningeal artery and the posterior meningeal artery.
The anterior branch of the middle meningeal artery runs beneath the pterion. It is vulnerable to injury at this point, where the skull is thin. Rupture of the artery may give rise to an epidural hematoma. In the dry cranium, the middle meningeal, which runs within the dura mater surrounding the brain, makes a deep groove in the calvarium. The middle meningeal artery is intimately associated with the auriculotemporal nerve, which swaddles around the artery manufacturing the two easily identifiable in the postmortem of human cadavers and also regularly damaged in incision.
Middle Meningeal Artery Cadaver
Rupture of the middle meningeal artery can cause epidural hematoma, an aggregation of blood between the dura mater and the cranium. This is a type of bleeding on the brain has a distinctive period in which the patient is aware and lucid. This lucid period is usually followed by dangerous breakdowns and possibly a coma, or even death.
Middle Meningeal Artery Foramen
The middle meningeal boulevard is a vital artery that plays an great clinical role. The middle meningeal artery (MMA) normally branches off the maxillary artery, which is an extension of the external carotid artery. The artery will then travel through the foramen spinosum, which is posterolateral from the foramen ovale, to supply blood to the dura mater. The middle meningeal artery arises from a complex embryological origin, which gives rise to abound anatomic fluctuations of the artery. information of these anatomic variations becomes important for surgeons to reduce the risk of complexities during surgical repair.
The middle meningeal artery has a company of clinical implications. Rupture of the artery, which most commonly occurs at the pterion, typically leads to an epidural hematoma. The resulting hematoma is described as a “lens-shaped” mass on CT scan. Damage to the middle meningeal artery may also result in an aneurysm or arteriovenous fistulas. Due to the middle meningeal artery’s attachment to the pain-sensitive dura mater, the artery also plays a role in migraine inconveniences
Structure and Function
The middle meningeal artery most often branches off the maxillary artery and courses into the middle cranial fossa via the foramen spinosum. The middle meningeal artery provides blood to the dura mater through and through its branching arteries also supplies the periosteum of the inner aspects of the cranial bones. As the middle meningeal artery enters the dura mater, it follows a fixed course as it embeds into the groove of the inner skull face. Due to the middle meningeal artery’s close contact to the inner skull, trauma to the lateral skull may result in rupture. The consequences of rupturing the middle meningeal artery will be further explained in the clinical significance section.
Embryology
The development of the middle meningeal artery, similarly to other blood vessels, occurs via angiogenesis and receives guidance from vascular endothelial growth factor (VEGF) and other growth factors. During development, a series of aortic arches arise, arranged from cranial to caudal. From these arches, the third arch gives rise to the stapedial artery. The stapedial artery arises from the internal carotid artery and is later incorporated by the external carotid artery. The stapedial artery will then divide, giving rise to the middle meningeal artery. By the 10th week of development, the stapedial artery will normally degenerate. Due to the complex nature of middle meningeal artery development, many anatomic variations and anastomoses may be seen.
Physiologic Variants
While the middle meningeal artery primarily is derived as a branch from the maxillary artery and then passes through the foramen spinosum into the middle cranial fossa, rare anatomical variations have been observed. It is important to be aware of the possible variations of the middle meningeal artery, to reduce the risk of thromboembolism during operative treatment of a lesion in the area. In cases where the foramen spinosum has been absent, the middle meningeal artery enters the cranial fossa through the foramen ovale alongside the mandibular nerve. The middle meningeal artery may also originate from the lateral aspect of the internal carotid artery. In this case, it will travel in the carotid canal, along with the internal carotid artery, and enter the skull through the foramen lacerum where it will then take a normal path and divide into anterior and posterior branches. The middle meningeal artery has also rarely originated from the posterior cerebellar artery, basilar artery, ascending pharyngeal artery, or ophthalmic artery. Due to the potential for variation in the middle meningeal artery, imaging should be acquired before undergoing invasive treatment.
Groove For Middle Meningeal Artery
The middle meningeal artery normally arises from the first or mandibular segment of the maxillary artery, just behind the condylar process of the mandible, and enters the skull through the foramen spinosum (see Fig. 2-10A–H). After passing through the foramen spinosum, the main stem courses laterally, grooving the greater sphenoid wing, where it divides in its anterior and posterior divisions, which supply the dura of frontal, temporal, and parietal convexity; the upper surface of the temporal bone; and the adjacent walls of the transverse and sigmoid sinus as well as the middle fossa dura adjacent to the cavernous sinus. In its path between the anterosuperior angle of the greater sphenoid wing and the sphenoid angle of the parietal bone, the anterior division, and sometimes the sphenoparietal sinus, can be encased in a bony canal that varies in extension from 1 to greater than 30 mm. The anterior division is usually single but may be composed of two branches (duplicated) in 0.8%, or absent in 0.7% of cases, while the posterior division is duplicated in 8.1%. At the level of the superior sagittal sinus the middle meningeal artery anastomoses with the anterior falcine branch of the ophthalmic artery to supply the dural layers of the falx.
The middle meningeal artery, and the osseous groove in which it courses, begins at the foramen spinosum and divide into anterior and posterior divisions 15 to 30 mm anterolateral to foramen spinosum. The anterior division and its groove divide behind the lateral part of the greater wing into a lateral branch, which passes across the pterion to reach the dura of the lateral convexity, and a medial branch, which courses medially along the lower surface of the sphenoid ridge where it anastomoses with the recurrent branch of the lacrimal artery. In 9 out of 10 orbits dissected, Liu and Rhoton reported the presence of anastomotic connections between the recurrent meningeal branch of the lacrimal artery and the medial branch of the anterior division of the middle meningeal artery. Occasionally, the recurrent meningeal branch of the lacrimal artery gives rise to the anterior segment of the middle meningeal artery or more rarely, the ophthalmic artery can give rise to the main stem of the middle meningeal artery itself.
In these cases, with an ophthalmic or lacrimal origin of the middle meningeal artery, the grooves marking the course of the main stem of the middle meningeal artery will originate at the lateral edge of the superior orbital fissure and the foramen spinosum will be hypoplastic or absent. Another, less frequent, site of origin of the middle meningeal artery is from the petrous portion of the internal carotid artery, referred to as a stapedial-middle meningeal artery, an anomaly that results from failure of the embryonic stapedial branch of the internal carotid artery to regress and allow the middle meningeal artery to become connected to the external carotid artery.
Epidural Hematoma Middle Meningeal Artery
The middle meningeal artery branches off the first part of the maxillary artery. It passes vertically through the roots of the auriculotemporal nerve and enters the middle cranial fossa via the foramen spinosum. Here it gives off two branches – superior tympanic branch and ganglionic branch – before dividing into anterior and posterior divisions:
The anterior division runs anterolaterally through the middle cranial fossa on the greater wing of sphenoid before coursing superiorly, often grooving the bone, and passes under the pterion before giving its terminal branches over the upper parietal bone.
epidural hematoma, which is most commonly due to traumatic rupture of the middle meningeal artery
- chronic recurrent subdural hematoma, which may be treated with middle meningeal artery embolization 3
- intracranial dural arteriovenous fistula, for which the middle meningeal artery is the most common arterial feeder
- meningioma, which may be embolized preoperatively via the middle meningeal artery