The Frankfort horizontal plane is defined as a line drawn between the inferior orbital rim and the supratragal notch (otherwise known as the tragion).1
It is used to standardize pre-operative photos for facial plastic surgery.
When this plane is parallel to the horizon when taking standardized photos, the patient is said to be in the Frankfort horizontal.
Bailey, Byron J., et al. “Chapter 170: Preoperative Evaluation and Facial Analysis in Facial Plastic Surgery.pdf.” Bailey’s Head and Neck Surgery - Otolaryngology, 5th ed., Wolters Kluwer, Lippincott Williams Et Wilkins, 2014. ↩