RESUMEN
BACKGROUND: Rhinoplasty techniques to affect nasal tip rotation are well described. Cephalic alar trim is a powerful method for achieving tip elevation. Previous studies and texts provide aesthetic guidelines for nasolabial angles. Often, surgeon experience determines the degree of lower lateral cartilage resection to achieve optimal results. This study analyzes the change in tip elevation with measured resections of the lower lateral cartilages. This can aid the surgeon in accurately predicting the effect of cephalic alar trim on tip elevation. METHODS: Ten fresh cadaveric dissections were performed to determine the change in nasolabial angles after cephalic trim of the lower lateral cartilage. Closed rhinoplasty technique was performed using marginal and intercartilaginous incisions to expose the lower lateral cartilage. Caliper measurements of the lower lateral cartilage were recorded. Serial cephalic trim was performed in 25% increments. True lateral photographs were obtained before and after each serial excision. Nasolabial angle measurements were obtained using a digital goniometer for digital photo analysis. RESULTS: Four female and 6 male cadavers were evaluated. The mean initial nasolabial angle was 106° ± 2°. The mean lower lateral cartilage width was 9.45 ± 1.38 mm. Serial 25% reductions in lower lateral cartilage height resulted in a mean total nasolabial angle change of 7.4°, 12.9°, and 19.6°, respectively. The mean incremental change in the nasolabial angle was 6.47° ± 1.25°. CONCLUSION: The nasolabial angle is an essential aesthetic feature. Cephalic trim is a key maneuver in affecting the nasolabial angle. A 25% lower lateral cartilage cephalic trim correlates with an average change in the nasolabial angle of 6.47°. Knowledge of the cephalic trim to nasolabial angle relationship aids in achieving desired tip elevation.
RESUMEN
BACKGROUND: Platysma innervation has various clinical applications. Although some patients have unsightly platysmal bands, others suffer from hyperkinetic motility disorders of the platysma that constitute both an aesthetic and functional impairment. Recently, the cervical motor branch has been used to reconstruct brachial plexus injuries. Dissection in this area can be precarious. The authors describe surface landmarks to help predict the location of the cervical motor branch of the facial nerve to more efficiently and safely operate in this area. METHODS: Sixteen fresh heminecks were dissected with the aid of loupe magnification. Measurements were taken to the branching point of the cervical nerve from the angle of the mandible and to a line from the mentum to the mastoid process. RESULTS: The cervical branch of the facial nerve was identified to branch below the mandible in all specimens. The branching point of the cervical nerve was consistently found in line with a perpendicular line from the angle of the mandible to the mastoid-mentum line. The branching point was located within 1.75 +/- 0.26 cm of this line. Dividing the mastoid-mentum line by the length of the ramus accurately predicted the distance from the angle of the mandible to the branching point. CONCLUSIONS: The cervical branch of the facial nerve can be reliably located within 1 cm below a perpendicular line from the angle of the mandible to a line drawn from the mentum to the mastoid process. Clinical applications of these findings range from cosmetic face-lift procedures to brachial plexus reconstructions.
