The Preoperative Evaluation On Adult Patients With Cleft Lip In Pyriform Hole Region By CT Three-Dimensional Reconstruction

BackgroundCleft lip is one of the common congenital disease, its clinical signs include: maxillary hypoplasia, the interrupting continuity of orbicular muscle of mouth, the alar cartilage dysplasia, the interrupting continuity of alveolar crest. Due to the different degrees of the deformity and the coplex and special structure, the reconstructive operation of the cleft lip has become a difficult task. Among the econdary lip and nasal deformities after operation caused by abnormal growth and development and the diffirences of one-stage surgical management, nasal deformity which includes low alar base and alar collapse is particularly obvious. Accurate measurement of the lip and nose before surgery is of great necessary in order to improve the scientific and accuracy in the choice of surgical management, and reduce the blindness and randomness of it. At present, people pay more attention to soft tissue diformity on the understanding of adult cleft lip, while the sduty about hard tissue deformity, especially the measurement of the piriform aperture area, is far less than it.3D measurement technique of CT is gradually favorred with its’ s advantages of “spatial structure of a full range of display, exact reconstruction of biological model, accuracy and precision”, and it is widely applied to clinical studies. Its’ s application in the measurement of maxillofacial provides an opportunity to the accurate diagnosis and precise measurement and a personalized and digital surgical management of the surgery. ObjectiveTo determine the consistency of craniofacial measurements using spiral computed tomography volume rendering by computer systems and sliding caliper. To compare the piriform aperture area osseous data between adult patients with cleft lip and healthy adults, and analysis its shape characteristics, and put forward a classification method of piriform aperture deformity. And choose appropriate surgical methods and appropriate materials according to the classification method. And providing imaging reference data of operation and the implementation of 3D bio printer. Methods1.Using spiral 3D-CT and display tools to examine twenty cadaver heads and to measurement the conventional craniometric anatomical landmarks.The consistency between the two measurements was analyzed by using SPSS17.0 software package.2.To compare the piriform aperture area osseous data between adult patients with cleft lip and healthy adults,analyse the relationship between the measuring project and grade the piriform aperture deformity. Results1. The results demonstrated no statistically significant difference between CT measurement and physical measurement. Proved that application of CT three-dimensional reconstruction can accurately measure the piriform aperture.2.Shift of the soft and hard tissue on the abnormal side of piriform aperture area was significantly and positively related.3.The classification of piriform aperture deformity.(x: the horizontal direction, y: the vertical direction, z: the dorsoventral direction)Mild deformity: x≤3.1mm, y≤2.2mm, z≤3.5mm,Moderate deformity: 3.1mm < x≤5.3mm,2.2mm< y≤5.6mm, 3.5mm <z≤5.5mm,Severe deformity: x > 5.3mm, y > 5.6mm, z > 5.3mm. Conclusions1. Application of CT three-dimensional reconstruction can accurately measure the piriform aperture.2. The nasal basal depression and shift deformity will be more significant when the depression and degree of the piriform aperture increase.3. To selecte the operation mode according to the degree of deformity.Mild deformity: Just soft tissue repair can achieve satisfactory results.Moderate deformity: Auxiliary using medical implants(cartilage, e PTFE, etc.) to correct the collapse deformities, and to alleviate the depression and shift of nasal base.Severe deformity: Comprehensive procedures including alveolar cleft repair, implanting e PTFE, the repairing of soft tissue and etc.