“Digital Diffusion” Technique for the Administration of Local Anesthetic in Eyelid Surgery

Abstract

This chapter describes an elegant local injection technique dubbed “digital diffusion” by Dr. Rona Z Silkiss. This technique minimizes tissue distortion and ecchymosis while providing for appropriate anesthesia and enhanced safety.

My preferred technique for the administration of local anesthetic has been named the “digital diffusion” technique. This technique involves the administration of a 50/50 mixture of 2 % xylocaine with 1: 100,000 epinephrine and 0.25 % Marcaine with 1: 200,000 epinephrine combined with NaHCO₃ and hyaluronidase. We add 0.5 ml of NaHCO₃ to 9 ml of the local mixture and 0.5 ml or less of the hyaluronidase to a total of 10 ml. The hyaluronidase may be ovine or bovine (Hylenex, Vitrase, etc.)

The local is injected in a single point in the lateral aspect of the eyelid, just below the skin. The needle is directed away from the globe in the event the patient moves his or her head or sneezes unexpectedly. One to 2 ml of local is placed into the eyelid at the single injection site. Using a gauze pad around a digit, the local is slowly wiped across the eyelid. This local then diffuses into the eyelid in a uniform distribution, without residual tissue distortion. Additionally, because the lid has only been injected in a single point, the risk of ecchymosis formation drops significantly. This is known as the “digital diffusion” of the local anesthetic.