Since Ayer first described the technic for puncture of the cisterna magna1 the procedure has been widely adopted; its advantages and indications have been discussed by numerous writers. Since November, 1929, cisternal puncture, with certain modifications of Ayer's method, has been carried out more than five thousand times at the Indianapolis City Hospital. The procedure was first adopted in treatment in a number of cases of basilar meningitis; later it was used in other cases.2 in which many cerebrospinal drainages were necessary. Several patients had more than thirty cisternal punctures; many of them more than ten. Vonderahe and Haberman3 reported a case of injury to the medulla and reemphasized the dangers of cisternal puncture and the need for preliminary practice on the cadaver. Since other accidents have been reported, perhaps the safeguards used on these patients merit a description.
TECHNIC
A needle of larger gage (16) that