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Quantifying Labial Strength and Function in Facial Paralysis: Effect of Targeted Lip Injection Augmentation
Heather Starmer1, Sofia Lyford-Pike2, Lisa Earnest Ishii2
1Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California.
JAMA Facial Plastic Surgery
|June 19, 2015
Summary
Facial paralysis significantly reduces lip strength, impacting speech and eating. Targeted lip injections effectively restore lip strength, improve articulation, and reduce food spillage in patients with facial paralysis or muscular dystrophy.
Area of Science:
- Reconstructive surgery
- Facial nerve disorders
- Neuromuscular diseases
Background:
- Facial muscle weakness from paralysis or muscular dystrophy impairs lip function, leading to speech difficulties and food spillage.
- Quantitative data on the impact of facial paralysis on lip strength are limited.
Purpose of the Study:
- To quantify the effect of facial paralysis and muscular dystrophy on lip strength.
- To evaluate the effectiveness of targeted lip injection augmentation for lip incompetence.
Main Methods:
- Prospective analysis of patients with lip incompetence due to facial paralysis or muscular dystrophy.
- Exclusion of patients who underwent direct surgical lip procedures.
- Assessment of lip pressure (Iowa Oral Performance Instrument), anterior bolus spillage, and articulation of bilabial sounds before and after treatment.
Main Results:
- Unilateral facial paralysis reduced central lip strength by 69% compared to the non-paralyzed side.
- Injection augmentation improved lip strength across the entire lip in unilateral facial paralysis and significantly in muscular dystrophy patients.
- Improved articulation of plosive sounds and decreased anterior bolus spillage were observed post-injection.
Conclusions:
- Labial strength is notably reduced in patients with unilateral facial paralysis.
- The Iowa Oral Performance Instrument effectively measures labial strength and treatment outcomes.
- Injection augmentation offers a simple, effective solution for improving lip function in facial paralysis and muscular dystrophy.
