The apical angle: a mathematical analysis of the ellipse.
نویسندگان
چکیده
BACKGROUND The elliptical excision is a common surgical procedure. The dermatologic literature predominantly describes an excisional geometry with a 3:1 length:width ratio and an apical angle of 30 degrees. OBJECTIVE To analyze the elliptical excision by applying mathematical principles and define the apical angle and its relationship to the length:width ratio. METHODS We examined numerous examples of elliptical excisions as presented in the dermatologic literature. We analyzed the geometry of the excisions and defined it mathematically. RESULTS The apical angle of a 3:1 elliptical excision is not 30 degrees. The true apical angle varies from 37 degrees to 74 degrees depending on excisional geometry. CONCLUSION The commonly presented apical angle of 30 degrees is incorrect and does not reflect the true apical angle of elliptical excisions.
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ورودعنوان ژورنال:
- Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.]
دوره 27 1 شماره
صفحات -
تاریخ انتشار 2001