Publication: Anatomy and histology of the frontalis muscle
Issued Date
2015-01-01
Resource Type
ISSN
15372677
07409303
07409303
Other identifier(s)
2-s2.0-84925392012
Rights
Mahidol University
Rights Holder(s)
SCOPUS
Bibliographic Citation
Ophthalmic Plastic and Reconstructive Surgery. Vol.31, No.1 (2015), 66-72
Suggested Citation
Bryan R. Costin, Thomas P. Plesec, Natta Sakolsatayadorn, Tal J. Rubinstein, Jennifer M. McBride, Julian D. Perry Anatomy and histology of the frontalis muscle. Ophthalmic Plastic and Reconstructive Surgery. Vol.31, No.1 (2015), 66-72. doi:10.1097/IOP.0000000000000244 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/36843
Research Projects
Organizational Units
Authors
Journal Issue
Thesis
Title
Anatomy and histology of the frontalis muscle
Abstract
© 2014 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc. Purpose: To determine the gross and histologic configurations of the medial and lateral frontalis muscle. Methods: After making a midcoronal incision and bluntly dissecting to the orbital rim, the frontalis muscle was marked and measured. A protractor was used to measure the frontalis-orbicularis angle (FOA) and, when present, the angle of central bifurcation (AOB). Three strips of full-thickness forehead soft tissue measuring 0.5 cm × 8 cm were excised 3, 4.5, and 6 cm above the supraorbital notch and analyzed histologically for the presence of skeletal muscle fibers. Data were analyzed using 2-sample t tests, paired t tests, Pearson correlations, and mixed effect models. A p value of ≤ 0.05 was considered statistically significant. Results: Sixty-four hemifaces of 32 cadavers (16 males) were dissected. All specimens were Caucasian. The average age was 78.2 years (range, 56-102 years). The average FOA was 88.7° (13.0° ), and the average AOB was 90.0° (26.4° ). A visible midline bifurcation occurred in 28 of 32 subjects (88%) at an average height of 4.7 cm (range, 2.4-7.2 cm) superior to the supraorbital notch. Continuous skeletal muscle fibers were present within the midline bifurcation histologically in 89%, 75%, and 11% of specimens 3.5, 5.0, and 6.5 cm above the supraorbital notch, respectively. In 46% of individuals, skeletal muscle fibers were continuously present microscopically within the gross bifurcation. Conclusion: While a medial frontalis muscle bifurcation occurs grossly in most senescent Caucasians, muscle fibers exist microscopically within this zone in nearly half of individuals.