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Published on: March 6, 2019
Advancing Techniques for Temporal Hollowing Correction: Insights from Ultrasound-Guided PLLA Injection
Furong Liu1, Guangyuan Qi2, Qingyang Liu3
1Department of Plastic Surgery, The Affiliated Friendship Plastic Surgery Hospital of Nanjing Medical University, No.146 Hanzhong Road, Nanjing, 210009, Jiangsu, China.
Background:
Temporal hollowing is primarily caused by congenital cranial dysplasia, as well as by acquired trauma and aging. In this case report, we investigated a novel approach to correcting temporal hollowing using poly-L-lactic acid (PLLA) injections, to identify a more effective injection technique and confirm its safety.
Methods:
Two patients underwent two-to-three ultrasound-guided PLLA injections, with intervals of one month between sessions. One side received subcutaneous injections, while the other side received fascia injections. Ultrasound imaging was utilized to ensure precise injection locations, and split-face analysis was conducted to compare the effects of the two techniques.
Results:
Both injection techniques effectively improved the temporal hollowing, resulting in significantly increased skin thickness. Both the researchers and the patients had a global aesthetic improvement scale of less than 3. Subcutaneous injections demonstrated a greater improvement in skin and subcutaneous fat thickness compared to fascia injections (p<0.05), although no significant difference was observed in the increase of fascia thickness between the two techniques (p>0.05). Additionally, subcutaneous injections were noted to have a shorter onset time compared to fascia injections (p<0.05). No adverse reactions were reported during the treatment or within six months post-procedure.
Conclusion:
Subcutaneous injection appears to offer a potential advantage in enhancing skin thickness and achieving faster results, though further validation in larger studies is required. This study highlights the potential of PLLA for temporal correction, emphasizing the critical role of ultrasound-guided precision and injection technique in ensuring efficacy and safety.
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 .

