Hyaluronic Acid Gel Injection for the Treatment of Tear Trough Deformity: A Multicenter, Observational, Single-Blind Study.

BACKGROUND: Hyaluronic acid (HA) gel injections were first used to treat the tear trough in 2005 and since then it has been a mainstay of the approach to lower eyelid deformities. OBJECTIVE: The authors present this retrospective multicentric observational study based on single-blind objective and subjective evaluation and patient satisfaction in relation to the aesthetic improvement of a large group of patients treated. METHODS AND MATERIALS: Between January 2016 and December 2019, 600 patients (468 women and 132 men), were enrolled in this study, and 1200 tear trough deformities were treated with both needle and cannula techniques. RESULTS: Average follow-up time was 12 ± 1 months, and the outcomes were assessed both objectively and subjectively with respect to Hirmand's classification. Statistical analysis shows an inverse correlation between age and class amelioration. CONCLUSION: HA injection of the tear trough is most effective in patients between 30 and 40 years of age, while its benefits extend to up to 50 years old; afterward, it should no longer be the treatment of choice. This confirms that correction of tear trough with hyaluronic acid injections may provide an option to achieve immediate and durable results for up to one year after the injection. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .