Fig 1.
The CAD model for finite element analysis and directions of forces for CAD model.
(A) A 25-year-old Chinese Han male patient with secondary unilateral cleft lip nasal deformity. (B) Width (x), thickness (y) and height (z) of the CAD model, composed of the nasal framework and the skin envelope. (C, D) The intercrural suture was simulated by a force vector (F1) which was set at the margin of the intermediate crus of the alar cartilage directing anteriorly and medially. (E, F) The suspension suture was simulated by a force vector (F2) set at the lateral crus of the alar cartilage directing superiorly and medially.
Table 1.
Definition of models for finite element analysis.
Table 2.
Elastic properties of materials in the model for finite element analysis.
Table 3.
Definition of FE model in ANSYS Workbench.
Table 4.
Statistical analyses of measured parameters among three groups.
Fig 2.
The TD on the nsaal framework and the TD and the EQV on the skin envelope.
(A) F1 alone at 5N. (B) F2 alone at 5N. (C) F1 and F2 both at 5N. (D) F2 alone at 15N. (E) F2 alone at 5N with bilateral alar cartilages merged together. Blue indicated the stable part as control. The changes of TD (mm) and EQV (kPa) were corresponding to color change.
Fig 3.
The TD and EQV on two paths on the skin envelope.
(A) Path one started from one alar base through the nasal tip to the alar base at the other side. Path one started from landmark one to landmark five: Landmark one represented the alar base at the cleft side; Landmark two represented the dome at the cleft side; Landmark three represented the nasal tip; Landmark four represented the dome at the non-cleft side; Landmark five represented the alar base at the non-cleft side. (B) Path two started from the columella base through the nasal tip to the nasal radix. Path two started from landmark one to landmark five: Landmark one represented the nasal radix; Landmark three represented the dorsum; Landmark four represented the nasal tip; Landmark five represented the columella base; Landmark two was the midpoint of the neighboring two landmarks. (C) The TD on Path one. (D) The TD on Path two. (E) The EQV on Path one. (F) The EQV on Path two. Lines of five colors represented five ways of force loading.
Fig 4.
The vectors of deformation under different types of force loading and the Schematic drawing for this operative technique.
(A) TD with F1 alone at 5N. (B) F2 alone at 5N. (C) TD with F1 and F2 both at 5N. (D) TD with F2 alone at 15N. (E) TD with F2 alone at 5N with bilateral alar cartilages merged together. The change of TD (m) was corresponding to color change. The length of the arrow represented the value of deformation, and the direction of the arrow represented the direction of deformation. To distinguish (B) and (E), the skin envelope was set in grey when loading F2 alone after merging two alar cartilages. (F, G) Schematic drawing of two different places on the medial crus to coapt the alar cartilages together in basal view: 1. High position of suture on the medial crus (F); 2. Low position of suture on the medial crus (G). (H) A representative case of unilateral cleft nose deformity repaired with the suspension suture and the passive intercrural suture.