About one year ago1 I described an apparatus for puncture of the superior longitudinal sinus. This consisted of a needle 4 cm. long, with obturator, which fitted into a rectangular block 3 cm. in thickness, thereby allowing 1 cm. of needle to project. By means of a set screw, the needle was made adjustable to any desired length up to 1 cm. This apparatus has been used extensively in the Babies' Hospital for the intravenous administration of arsphenamin, physiologic sodium chlorid solution, glucose solution and sodium bicarbonate solution, as well as for the withdrawal of blood for diagnostic purposes. A slight modification has suggested itself which greatly simplifies the procedure of sinus puncture and still further minimizes the risk of injuring the wall of the sinus or the cerebral cortex.
Showing how the block of the needle is bevelled.
The original instrument entered the sinus at right angles to