THE NOSE. 



99 



nodes; while enlargement of the deep cervical lymphatics follows disease of the 

 deeper nasal cavities. 



Nasal hypertrophies are enlargements of the nasal mucous membrane. The 

 mucous membrane of the nose or Schneiderian membrane has columnar ciliated cells 

 on its surface and mucous cells beneath. It is prolonged into the various sinuses and 

 cavities in connection with the nasal fossae. The membrane on the upper third of 

 the septum, the upper portion of the middle turbinated, and the superior turbinated 

 bone, contains the terminal filaments of the olfactory nerve. The membrane over 

 the lower portion of the septum, over the lower edge of the middle, and the greater 

 part of the inferior turbinated bones, contains a venous plexus which renders it 

 erectile. On the slightest irritation this portion of the membrane will swell and 

 obstruct the passage of air through the nostrils. Repeated swelling of the membrane 

 of the septum produces thickenings of the septum, which if anterior may be seen 

 through the nostrils, and if posterior by the rhinoscopic mirror. The membrane 



Spur 



Spur 



Nasal crest 



FIG. nS. Nasal crest and septal spurs. 



over the inferior turbinated bones also becomes swollen and enlarged, constituting, if 

 at the forward end, anterior hypertrophy, and if at the posterior extremity, posterior 

 hypertrophy ( Fig. 120). They can be readily seen through the nasal speculum ante- 

 riorly and by the rhinoscopic mirror posteriorly. They are treated by applications of 

 acids, as chromic and trichloracetic, by the electrocautery, or are snared off with the 

 cold snare. Snaring is more often employed in reducing posterior hypertrophies, but 

 both the anterior and posterior can be reached by an electrocautery point or a knife 

 introduced through a speculum in the anterior nares. 



The Outer Wall. The outer wall has on it the three turbinated bones 

 superior, middle, and inferior. The inferior is a separate bone, but the middle and 

 superior are parts of the ethmoid bone (Figs. 121 and 122). 



The inferior meatus is between the inferior turbinated bone and the floor of 

 the nose. The lachrymonasal duct enters this meatus just below the anterior end 

 . of the inferior turbinated bone. It pierces the mucous membrane obliquely, bemg \ \ ' ' 

 guarded by a fold called the valve of Hasner. The opening^ is ; not y is; ble frqijv.the. \ \' 

 anterior nares and usually it is impossible to introduce a pr.ooe -into" it -from th'etn. 



