A Novel Neurovascular Protection Method In Nasolabial Muscle Biomechanical Bionic Surgery For Secondary Unilateral Cleft Lip Repair: A Three-Dimensional Evaluation Of Short And Long-Term Results.

BACKGROUND: Neurovascular protection within the upper lip muscles is essential in muscle tension reconstruction and functional recovery during surgery. This study aimed to investigate a novel neurovascular protection method based on the intramuscular neurovascular partitions of the upper lip applied to nasolabial muscle biomechanical bionic surgery for secondary unilateral cleft lip repair and to evaluate postoperative outcomes.

METHODS: From November 30, 2019 to October 31, 2020, 50 consecutive patients with secondary unilateral cleft lips who underwent the modified biomechanical bionic surgery were reviewed retrospectively. Three-dimensional (3D) photographs of patients were collected preoperatively, 7-day postoperatively, and during long-term follow-up (at least 6 months). The Global Aesthetic Improvement Scale was used to evaluate surgical subjective outcomes, and statistical analysis of nasolabial measurements on 3D photographs was used to evaluate objective outcomes before and after surgery.

RESULTS: The Global Aesthetic Improvement Scale showed that 94% of patients had improved upper lip morphology and 92% had improved nasal morphology 7-day postoperatively. In all, 84% maintained favorable nasolabial morphology during long-term follow-up. Statistical results showed that the postoperative alar width, philtral depth, columellar angle, and nasal base inclination angle were significantly improved compared with preoperatively (P<0.01). The differences between the above 4 indexes were not statistically significant (P >0.05) between 7-day postoperatively and long-term follow-up, indicating that the postoperative lasting outcomes were satisfactory.

CONCLUSIONS: The novel method of neurovascular protection in nasolabial muscle biomechanical bionic surgery can achieve a long-term improvement of labial-nasal morphology and function in patients with secondary unilateral cleft lip.