Novel anatomical modeling method helps quantify mechanical properties of lower lateral cartilage
Using plastic surgeons’ expertise along with anatomically correct models of nasal structures, researchers found the ideal lower lateral cartilage should maintain a minimum elastic modulus of 3.65 MPa to provide proper form and function in the nose.
The researchers created five anatomically correct lower lateral cartilage (LLC) phantoms from urethane using 3-D computer modeling and an injection-molding process. The five models varied in stiffness in the intermediate crural region from 0.63 MPa to 30.6 MPa.
Thirty-three experienced facial plastic surgeons, plastic surgeons and otolaryngologists rated the mechanical phantoms in order of increasing stiffness. Phantoms were masked by the rating surgeons and allowed to be touched and examined in any way necessary.
The surgeons were given an accuracy rating as to how well they ordered the phantoms and asked to choose a single phantom they believed to have the minimum acceptable stiffness for LLC to maintain proper form and function in the human nose.
Using a binary logistic regression, the researchers created a curve specifying the probability of mechanical acceptability as a function of elastic modulus of the intermediate crus. Additionally, the goodness of fit between the logistic regression and survey data was measured using a Hosmer-Lemeshow test.
The most popular selection was found to be Phantom 4, with a modulus of 3.97 MPa, according to the researchers. The minimal required elastic modulus of human LLC was found to be 3.65 MPa, based on this model. Additionally, the Hosmer-Lemeshow test demonstrated a good fit between the logistic regression and survey data, the researchers reported. - by Abigail Sutton
Disclosure: The researchers report no relevant financial disclosures.