DISEASES OF ARTERIES. 



The chief morbid conditions seen in arteries are : Wounds, in- 

 flammation, thrombosis, embolism, degeneration, and aneurisms. 

 Wounds belong essentially to surgery. 



ARTERITIS. EMBOLISM. 



Internal and external arteritis. Thrombosis, from inflammation. Em- 

 bolism. Bruising. Stretching. Ligature. Lesions. Extension of clot, 

 color, consistency, adhesion, lamination. Composition of clot. Condition 

 of vessel. Changes in muscles. Causes : muscular tension, embolism. 

 Heart clots, venous clots. Infecting debris. Symptoms : paresis or par- 

 alysis on exertion. Local suffering, tenderness, firm swollen artery, de- 

 rangement of nutrition and function, atrophy. Chronic arteritis : Ather- 

 oma. Changes in serosa. Fibrous thickening, atrophy, dilatation. 

 Strongylus. Treatment : rest, anodynes, alkalies, massage. 



Inflammation of arteries has been divided into external and 

 internal arteritis, according as it affects the fibrous sheath of the 

 artery or its inner lining membrane. 



In external arteritis the exudation of lymph often forms a 

 protecting layer around the vessel, while the inner coats continu- 

 ing sound the current of blood remains unimpaired. Even when 

 suppuration takes place in the vicinity of a large artery, that 

 vessel may pass through the center of the abscess and convey the 

 blood as freely as before. The nutrition of the vessel thus de- 

 tached from the surrounding tissues is maintained by its accom- 

 panying nutrient artery, though if the abscess is large there is 

 danger of a deficient supply. The frequent presence of such 

 arteries traversing an abscess should make the surgeon careful 

 how he breaks down the bright pink bands occasionally seen to 

 stretch across such cavities. 



Internal arteritis, or inflammation of the internal coat of an 

 artery is incomparably more serious and mainly because it deter- 

 mines the coagulation of the contained blood and consequent 

 plugging of the vessel. This is but one manifestation of the gen- 

 eral law that in inflamed tissues the fibrine forming elements are 

 produced in excess, and when blood comes in contact with these 

 it tends to coagulate (thrombosis). On the other hand the in- 

 flammation in the arterial coats may ensue from the pressure of a 



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