Anatomy of the corrugator supercilii muscle: part I. Corrugator topography.

BACKGROUND Complete corrugator supercilii muscle resection is important for the surgical treatment of migraine headaches and may help prevent postoperative abnormalities in surgical forehead rejuvenation. Specific topographic analysis of corrugator supercilii muscle dimensions and its detailed association with the supraorbital nerve branching patterns has not been thoroughly delineated. Part I of this two-part study aims to define corrugator supercilii muscle topography with respect to external bony landmarks. METHODS Twenty-five fresh cadaver heads (50 corrugator supercilii muscles and 50 supraorbital nerves) were dissected to isolate the corrugator supercilii muscle from surrounding muscles. Standardized measurements of corrugator supercilii muscle dimensions were taken with respect to the nasion and lateral orbital rim. RESULTS Relative to the nasion, the most medial origin of the corrugator supercilii muscle was found at 2.9 +/- 1.0 mm; the most lateral origin point, 14.0 +/- 2.8 mm. The lateralmost insertion of the corrugator supercilii muscle measured 43.3 +/- 2.9 mm from the nasion or 7.6 +/- 2.7 mm medial to the lateral orbital rim. The most cephalic extent (apex) of the muscle was located 32.6 +/- 3.1 mm cephalad to the nasion-lateral orbital rim plane and 18.0 +/- 3.7 mm medial to the lateral orbital rim. There were no statistical differences noted between the right and left sides. CONCLUSIONS The dimensions of the corrugator supercilii muscle are more extensive than previously described and can be easily delineated using fixed bony landmarks. These data may prove beneficial in performing safe, complete, and symmetric corrugator supercilii muscle resection for forehead rejuvenation and for effective decompression of the supraorbital nerve and supratrochlear nerve branches in the surgical treatment of migraine headaches.