856 



PETEE EASSOE 



opens the dura widely so as to expose the frontal lobe. With the patient 

 almost in a standing position and head held hack the frontal lohe is allowed 

 to gravitate out of the anterior fossa and is protected by imbricating layers 

 of rubber tissue. The chiasma and hypophysis are, brought into view quite 

 readily, and a tumor of the latter may be removed in toto by means of a 

 snare. The advantages claimed by Adson for this operation are: "1. Its 

 approach presents a dry field, free from infection, in which it is compara- 

 tively easy to expose the optic commissure and the tumor. 2. The expos- 



T\ff. 25. Exposure of hypophvseal tumor by intracranial method. (After A. W. 

 Adson, J. Am. M. Assn., 1918.) 



nre permits the dissection of the tumor from the optic nerves and the 

 commissure and the removal of all or any portion of the tumor and pitui- 

 tary body that is desired. 3. Trauma of the commissure and nerves is 

 prevented, as the sponging is done against the floor of the sella instead of 

 working upward against the commissure and nerve peduncles." 



Indications for and Choice of Operation. Signs of involvement of the 

 optic nerves and persistent, severe headache when not relieved by X-ray 

 treatment, or showing no tendency to spontaneous disappearance, call for 

 surgical relief. In early acromegaly the tumor is likely still to be within 

 the sella, and the headache to be caused by distention of the dural capsule 



