The constant changes that follow sympathetic ganglionectomy and ramisectomy have been attributed clinically to the increased flow of blood to the extremities, as shown by studies with the calorimeter and the thermocouple, but these conclusions have been based only on physiologic observations. In order to investigate the possibility of establishing an anatomic basis for the explanation of clinical results in such conditions as Raynaud's disease, thrombo-angiitis obliterans and polyarthritis, lumbar sympathetic ganglionectomy and ramisectomy was performed on animals.
Following operation, an opaque medium was injected into the arterial tree, and the arterial tree was then studied by means of the roentgen ray. In view of the fact that the animal on which the experiment could be conducted successfully must necessarily be one that could withstand an anesthetic and be of sufficient size to demonstrate any gross changes in the caliber of the vessels, dogs were chosen. In order that the