78 SURGICAL APPLIED ANATOMY. [Chap. vi. 



that springs usually from the mucous membrane 

 over the middle or inferior turbinate bones, and the 

 fibrous or sarcomatous polyp that usually takes origin 

 from the periosteum of the nasal roof, or from that of the 

 base of the skull. Polypi of the latter kind spread in 

 every available direction. They expand the bridge ,of 

 the nose, close the nasal duct and cause epiphora, 

 depress the hard palate and encroach upon the mouth, 

 invade the antrum and expand the cheek, grow down 

 into the pharynx, pushing forwards the velum palati, 

 and may penetrate even through the inner wall of the 

 orbit. In one remarkable case quoted in the Lancet 

 for 1877, a tumour springing from the sheath of the 

 superior maxillary nerve just after its exit from the 

 foramen rotundum, projected into the nasal fossse. It 

 was mistaken for a polyp, and attempts to remove it 

 led to meningitis and death. 



The blood supply of the nasal cavity is exten- 

 sive, and is derived from the internal maxillary, 

 ophthalmic, and facial arteries. With regard to the 

 veins, it may be noted that the ethmoidal veins that 

 come from the nose enter the ophthalmic vein, while 

 in children a constant communication exists between 

 the nasal veins and the superior longitudinal sinus 

 through the foramen caecum. This communication 

 may also be maintained in the adult. These connec- 

 tions may, in part, serve to explain the occurrence of 

 intracranial mischief as a consequence of certain in- 

 flammatory affections of the nasal cavities. Bleeding 

 from the nose, or epistaxis, is a common, and often a 

 serious circumstance. Its frequency is to a great ex- 

 tent due to the vascularity of the mucous membrane, 

 to its laxity, and to the fact that the veins, especially 

 those over the lowest turbinate bone, form extensive 

 plexuses, and produce a kind of cavernous tissue. The 

 epistaxis is often due, therefore, to interference with 

 the venous circulation, as seen in cases of cervical 



