ABSTRACT
Objective To determine the value of MR cholangiography(MRC)in the preoperative evaluation of biliary anatomy of living liver donors.Methods Fifty eight consecutive donors underwent MRC examinations and living liver transplantation.MRC was performed on a 1.5 T scanner with breath-hold rapid acquisition of T_2WI slab and breathing-gating 3D FSE T_2WI.Images of MRC and IOC were compared and classified according to the modified Huang's classification.Results Thity four(58.6%)liver donors showed normal biliary anatomy on IOC,and 24(41.4%)donors revealed variant bile anatomy.MRC correctly depicted biliary anatomy in 91.4%(53/58)donors.The sensitivity,specificity,positive predictive value and negative predictive value of MRC in distinguishing normal and difierent types of variant biliary anatomy were 83.3%(20/24),100%(34/34),100%(20/20),89.5%(34/38)respectively.Conclusion MRC can accurately assess the biliary anatomy in living liver donors and may guide the preoperative planning of liver transplant.
ABSTRACT
Objective To construct a geometric skull model by using three-dimensional reconstruction, computer tomography scanning and rapid prototyping technology and evaluate its significance in treatment of complex oral and maxillofacial deformities. Methods A cranial and a goldenhar syndrome patient with complex oral and maxillofacial deformities bone received continuous volumetric scanning of skull and the data acquisition was done by an electron computed tomography, by which reconstruction was performed and the obtained images saved as STL files. Then the data were input into rapid prototyping machine to make three-dimensional geometric model. Direct measurement, designation and surgery simulation could be done on this three-dimensional model. Then the mandibular mirror physical model was manufactured using rapid prototyping according to the normal side. Results A computer-aided model according to CT data could represent the three-dimensional anatomic structures and their relationships precisely. The replica exhibited dimensional errors ranging 0.02 mm to 0.53 mm. Which provided strong basis for accurate understanding of disease status and reasonable surgical plans and helped improve the curative effect of surgery. Conclusion Rapid prototyping can help surgeons in many ways for therapy of the complex oral and maxillofacial deformities.