Matrilin-2 within a Lysine Modified Chitosan Scaffold Promotes Nerve Regeneration in a Rat Sciatic Nerve Defect through Enhancement of Schwann Cell and Axonal Outgrowth
Elena Millesi, MD1,2, Carrie E Robertson, MD2, Waleed Gibreel, MD2 and Samir Mardini, MD2, 1Medical University, Vienna, VIE, Austria, 2Mayo Clinic, Rochester, MN
Introduction:
Facial synkinesis describes the unintentional co-contraction of the facial muscles due to aberrant nerve regeneration. Standardized grading scales play an invaluable role in evaluating the degree of severity as well as course of disease. While the House Brackman score is well recognized as a useful tool for facial palsy, there is no similar scale or scoring available for synkinesis. Hence, the purpose of this study was to develop the first facial synkinesis grading system, which should aid in defining disease severity and analyzing facial synkinesis progression uniformly in the future.
Methods:
Clinically experienced surgeons and neurologists at a tertiary center evaluated twenty synkinesis patients, which were then categorized either as mild, moderate, or severe. Based on identified patterns in facial features in each category, a scoring system was developed to ensure a higher score in a severe patient and a lower score in a mild patient. The scoring system underwent gradual elimination of redundant synkinetic features, thereby improving usability of the grading tool without interfering with its accuracy. In order to verify reproducible, consistent, and user-independent results, ten un-biased individuals with different medical backgrounds were asked to grade the same 6 patients, two of each category.
Results:
This novel grading system consisted of three rows with five columns each. Synkinesis severity was assessed as the patient was at rest, during a gentle smile and full smile. A gentle smile was defined as a smile without teeth showing and a full smile as maximum smile. Evaluated facial features included the nasolabial fold, the chin, the philtrum, the platysma, the upper lip, the lower lip, the corner of the mouth and eyelid closure. The maximum score achieved was 21 points. Based on the final score, the degree of synkinesis was differentiated in mild, moderate, and severe. No significant difference was observed in the final results of each evaluated patient scored by the independent individuals, thereby highlighting the accuracy as well as consistency of this scale.
Conclusion:
This study presents a user-friendly, accurate facial synkinesis grading scale, which will help determine the severity of facial synkinesis. Moreover, it will enable uniform analysis of disease progression and evaluation of treatment efficacy in the future.
Back to 2024 ePosters