Transillumination (TL) is a noninvasive technique that appears to allow preliminary detection of superficial vascular structures of the face to avoid intravascular HA injection. The purpose of our study was to test the efficacy of TL in terms of its sensitivity to locate vessels in the areas undergoing treatment and to reduce post-injection vascular complications.

Transillumination was used during the injection of hyaluronic acid to reduce the risk of intravascular injection. For the purpose of randomization, patients were asked to choose a sealed envelope. Inside the envelope was a piece of paper indicating on which side of the face (right or left) the transillumination would be used.

For each filler injection, transillumination was used on one side; on the other side of the face, the injection was administered without the use of any vascular exploration method. After the vessels had been located on the side chosen for the transillumination technique, a skin-marker pencil was used to draw the vascular mapping of the upper part of the face, which in our opinion represented the area most at risk of complications, the middle and the lower parts of the face.

Then ice was applied on both sides of the face for 15 s before to proceed with the injections in order to cause vasoconstriction and to further decrease the risk of an intravascular injection.Transillumination sensitivity for locating the vessels of the face was assessed.

Inclusion Criteria:

• Patients presenting for facial injections of hyaluronic acid

Exclusion Criteria:

• Patients with a history of allergy to a component of hyaluronic acid
• Patients with arteritis (Horton)
• Patients who have had previous facial surgery
• pregnant or nursing patients

The operator will guarantee the confidentiality of the part of facial where the trasillumination was used, the assessors will not be aware of the part of the face where the transillumination was used.