Six cases of vascular compromise after hyaluronic injection are reported. Clinical symptoms realized a Nicolau syndrome, which is characterized by immediate pain, livedoid pattern and a few days later by the appearance of scabs and skin necrosis. This type of complication is rare, but may be dramatic and injectors must be aware of that. A thorough knowledge of facial anatomy is mandatory to avoid the risky facial areas. The use of a flexible cannula instead of a sharp needle has much less risk of hurting vessels and must be preferred. The support of the patient is discussed and a treatment protocol is proposed.