Structure of Anastomosed Blood Vessels. i 5 1 



95 (505) 



Further observations on the structure of anastomosed blood 



vessels. 



By C. 0. GUTHRIE. 



[From the Department of Physiology and Pharmacology of the 

 University of Pittsburg.] 



In this series of experiments the theoretical optimum conditions 

 were fulfilled, i. e., very rapid auto-grafts were made and the use 

 of salt or other foreign solution avoided. A segment of common 

 carotid artery interposed between the ends of a divided common 

 carotid artery for twenty-eight days shows very slight or no altera- 

 tion excepting at the lines of anastomosis where a moderate thick- 

 ening occurred, due no doubt to trauma. A segment of external 

 jugular vein similarly engrafted on common carotid artery for 

 twenty-eight days shows a moderate and somewhat irregular thick- 

 ening of the wall, but the thickening is not nearly so great as in 

 another such experiment previously reported. 1 The intima is smooth 

 and glistening but yellowish, particularly in the more thickened 

 areas. The latter are very richly supplied with apparently newly 

 formed blood vessels. Muscle fibers are almost or entirely absent. 

 Elastic fibers are fairly abundant in the middle coats. The re- 

 mainder of the tissue is more or less hyaline in appearance. The 

 adventitial coat is the most thickened and dense, perivascular fibro- 

 sis apparently having occurred. 



A very different picture is presented by an internal jugular vein 

 and its branches in which the circulation was changed to arterial 

 and reversed by anastomosis of the peripheral end of the vein to 

 the central end of the common carotid artery after division of the 

 vessels. On opening the vessel, ten months and twenty-seven days 

 after the operation, it does not collapse as an ordinary vein. The 

 wall is more rigid, thicker and more transparent. The intima is 

 smooth and glistening. Muscular and elastic fibrous tissues are 

 present. The plain fibrous tissue is greatly increased in amount 

 and density, particularly in the middle and outer coats. Nutrient 

 blood vessels are present but they are not nearly so conspicuous 

 as in the venous segment. 



*Surg., Gynec, and Obs., 1906, ii, 266. 



