Arteritis of the Spinal Cord and Membranes. 169 



part of this blood passes into the large vessels which supply the 

 liver, spleen, kidneys, stomach, bowels, and hind limbs, and 

 while embolism is well known in these parts it has not been 

 demonstrated as yet in the spinal cord. The toxins produced in 

 infectious diseases and circulated in the blood can often lead to 

 destruction of the endothelium, and inflammation of the deeper 

 structures. In this way any circulating microbes find a ready in- 

 fection atrium. Hektoen seems to have demonstrated this in the 

 case of tubercular meningitis. By pressure of the neoplasm on the 

 vessel or by fibroid thickening and contraction of the walls of the 

 vessel, the subsidiary cord is denied its full supply, and degenera- 

 tion of the nervous substance is invited. In the human subject 

 degeneration of the cord has been shown to follow the line of 

 such diseased arteries. Thrombosis follows in every ca.se in 

 which the serous coat is Mivolved, and embolism can easily occur 

 from clots small enough to enter the capillary vessels. Lamy's 

 experiment of blocking the small arteries with inert powder, 

 shows that this will give rise to foci of hemorrhagic .soften- 

 ing, which connnence in the gray .substance. The blocking, how- 

 ever, must be multiple to produce any material effect, as the free 

 anastomosis of the .spinal capillaries otherwise secures an abund- 

 ant blood supply to adjacent parts. In case of an infective em- 

 bolism the disease will advance even if the obstruction is single. 

 The general symptoms of these conditions would depend on the 

 exact seat of the lesion, and treatment would have to proceed on 

 general principles, the object being to check the inflammatory 

 conditions, and trust to the vis medecatrix natnra- in connection 

 with rest and good hygienic conditions. 



