Detection of the Safe Zone for Upper Eyelid Hyaluronic Acid Injections.

Background: Hyaluronic acid (HA) injections for upper eyelid volumisation are safe procedures with short downtime and low complication rates. Nevertheless, the upper eyelid is a high-risk area for vascular complications because of its rich vascular network. After injection, bruising, an indicator of vascular penetration, develops very often and prolongs the short downtime. Aims: To describe a pain-controlled withdrawal technique for minimizing vascular complications and to examine the effects of topical anaesthesia administered prior to injection on complications related to vascular penetration. Methods: HA was injected into the upper eyelids of 25 patients using the pain-controlled withdrawal technique without topical anaesthesia. The patients' median age, complication rates, average amount of HA administered, and follow-up periods were evaluated. In addition, the patients were asked to evaluate their pain during injection using a numerical pain rating scale. Results: The patients' mean age was 40.4 ± 7.3 years. Minimal eyelid edema developed in all patients but did not prevent any of the patients' social activities. No bruising was detected in any of the patients, and no major vascular complications, such as blindness or cerebrovascular events, developed. The average amount of HA administered was 1.43 ± 0.45 cc. All patients evaluated their pain during injection as mild. Conclusions: With the pain-controlled withdrawal technique, none of the patients had minor or major complications due to vascular penetration. The procedure was well tolerated by the patients. The detection of the safe injection zone allowed the administration of more than the standard/accepted 01 cc HA (up to 0.3 cc) from one point.