246 THE MICROSCOPIST. 



INFLAMMATION. 



Inflammation is a complex process, beginning with an 

 increased flow of blood into or towards the part affected, 

 and generally leading to exudation or suppuration, some- 

 times healing by resolution or leading to new formations, 

 to various metamorphoses, or to destruction of tissues, 

 with a disturbance of the function of the part affected. 



Inflammation of the various tissues or organs are dis- 

 tinguished by adding the termination itis to the Latin or 

 Greek term, as encephalitis, pleuritis, nephritis, etc. ; or a 

 special name is given, as pneumonia, for inflammation of 

 the lungs, erysipelas, for inflammation of the skin, etc. 



Inflammations of serous coverings of organs receive the 

 prefix peri, as perihepatitis, perimetritis, etc. (except peri- 

 bronchitis, and peri phlebitis, which refer to inflammation 

 of the exterior of the bronchial or venous wall). Inflam- 

 mations of the surrounding connective tissue or appen- 

 dages of an organ are known by the prefix para, as para- 

 nephritis, paraeystitis, parametritis, etc. 



Inflammation is the result of some kind of injury to 

 the tissue affected, either direct, as from mechanical or 

 chemical agents, or indirect, as from specific contagions, 

 exposure to cold, etc. 



The first phenomenon of inflammation is congestive 

 hypersemia, or an increased flow of blood. There is first 

 a dilatation of the vessels, with an acceleration of the 

 current, which is soon followed by a retardation of the 

 current, producing stagnation or cessation of circulation. 

 Several theories have been advanced to explain this phe- 

 nomenon. According to the paralytic theory the irrita- 

 tion affects only the sensitive nerves, e. g., of the skin, 

 and produces an antagonistic paralysis in the vasomotor 

 nerves. The vessels then relax, dilate, and receive more 

 blood. According to Virchow and Beale, it is the cell in 



