560 



ANGIOLOGY 



I 



The branches of this vessel may be divided into three groups (Fig. 511), corre- 

 sponding with its three divisions. 



Branches of the First or Mandibular Portions. 



Anterior Tympanic. 

 Deep Auricular. 



Inferior Alveolar. 



Middle Meningeal. 

 Accessory Meningeal 



The Anterior Tympanic Artery (a. tympanic.a anterior; tympanic artery} passes 

 upward behind the temporomandibular articulation, enters the tympanic cavity 

 through the petrotympanic fissure, and ramifies upon the tympanic membrane, 

 forming a vascular circle around the membrane with the stylomastoid branch of 

 the posterior auricular, and anastomosing with the artery of the pterygoid canal 

 and with the caroticotympanic branch from the internal carotid. 



Art. ofPteri,ff 0il 



alveolar 



Mid. 

 meningeal 



Ant. 

 tympanic 



\Mylohyoid 



FIG. 511. Plan of branches of internal maxillary- artery. 



The Deep Auricular Artery (a. auricularis profunda) often arises in common with 

 the preceding. It ascends in the substance of the parotid gland, behind the tem- 

 poromandibular articulation, pierces the cartilaginous or bony wall of the external 

 acoustic meatus, and supplies its cuticular lining and the outer surface of the 

 tympanic membrane. It gives a branch to the temporomandibular joint. 



The Middle Meningeal Artery (a. meningea media; medidural artery) is the largest 

 of the arteries which supply the dura mater. It ascends between the spheno- 

 mandibular ligament and the Pterygoideus externus, and between the two roots 

 of the auriculotemporal nerve to the foramen spinosum of the sphenoid bone, 

 through which it enters the cranium; it then runs fonvard in a groove on the great 

 wing of the sphenoid bone, and divides into two branches, anterior and posterior. 

 The anterior branch, the larger, crosses the great wing of the sphenoid, reaches the 

 groove, or canal, in the sphenoidal angle of the parietal bone, and then divides 

 into branches which spread out between the dura mater and internal surface of 

 the cranium, some passing upward as far as the vertex, and others backward to 

 the occipital region. The posterior branch curves backward on the squama of the 

 temporal bone, and, reaching the parietal some distance in front of its mastoid 

 angle, divides into branches which supply the posterior part of the dura mater and 



