The value of the superior longitudinal sinus as a route for venipuncture for therapeutic and diagnostic purposes in young infants has recently been established. This procedure is now generally accepted as safe and practical. Tobler1 was the first to study the anatomic relations of the sinus for the purpose of using it as means of obtaining blood and administering fluids. He showed that the puncture is best made in the midline at the posterior angle of the fontanel, where the sinus has its greatest depth. Tobler's measurements show that the distance from the skin to the lumen of the vein is from 2 to 5 mm., according to age and individual variations, and that the depth of the sinus at the posterior angle of the fontanel varies from 4 to 7 mm.
While sinus punctures are now made in practically every hospital for infants whenever venipuncture is necessary, a