Hyaluronic acid is superior to autologous fat for treatment of temporal hollowing after lateral orbital wall decompression: A prospective interventional trial.

Purpose: To compare injections of hyaluronic acid (HA) and autologous fat (AF) for the treatment of unsightly temporal hollowing after lateral orbital wall decompression in thyroid eye disease.

Methods: In this nonblinded prospective comparative interventional study, patients received injections of HA in the right temple and AF in the left temple. Additional injections were given when needed at follow-up after 6, 12, 18, and 24 months. Follow-up included an interview; clinical examination with an evaluation of symmetry, contour, and skin surface; and ultrasound measurements. From photographs, the temporal hollowing was graded 1-3. The main endpoints were grading of temporal hollowing and temporal soft tissue thickness.

Results: Seventeen patients were treated bilaterally and 12 unilaterally (five received HA and seven AF). Injection(s) of HA and AF administered at each site were a median (range) of 1 (1-4) and 2 (1-5), respectively. The total combined volume of HA injected per site was 0.9 (0.2-2.0) ml and that of AF was 3.1 (0.5-9.6) ml. At the final examination, a statistically significant difference in mean (SD) grading scores of temporal hollowing due to HA (1.18 (0.26)) compared to those of AF (1.85 (0.44)) was observed (p < 0.001). Six months after administering an injection of HA, the temporal soft tissue thickness was 2.35 (0.24) cm compared to 2.19 (0.28) cm obtained with an injection of AF (p < 0.001). By using a linear mixed-effect model and adjusting for baseline values, age, sex, and refill, the difference in favor of HA persisted at all later follow-ups. Increased fibrosis of the subcutaneous tissue developed at 5/24 sites that received AF.

Conclusion: Injection of HA is superior to that of AF for treating temporal hollowing after lateral orbital wall decompression.