Automatic Positioning Algorithm For Femoral Anatomical Axis In CT Images Based On Scatter Fitting

Femoral head necrosis is a common disease of all ages.A new type of femoral head resurfacing surgery can treat this disease more effectively.In order to ensure the smooth progress of the operation,surgical instruments need to be placed along the anatomical axis of the femoral shaft and femoral neck.In the direction of placement.Therefore,the positioning of the femoral anatomical axis will directly affect the smooth progress of the operation.After analyzing the existing methods of femoral anatomical axis positioning,an anatomical axis positioning scheme for femoral shaft and neck based on random sampling consensus algorithm was designed.In the image preprocessing module,the method of resampling is used to unify the pixel pitch.In the positioning algorithm of the femoral shaft anatomical axis,a more robust random sampling consensus algorithm is used to do scatter fitting.In the femoral neck anatomical axis positioning algorithm,a new algorithm is proposed.By morphologically expanding the femoral head by 1.3 times,an annular area with a distance between 1.3r and 1.3r + 2 from the center of the femoral head is obtained(where r is the radius of the femoral head),by finding the intersection of this annular area and the femoral area,a "potato chip-shaped" area can be obtained,and the sum of all points in this area can be averaged to determine the other on the femoral neck point.This study used the three-dimensional CT images of the femoral region provided by the project partner to conduct experiments.In the experiment,43 sets of normal data and31 sets of pathological data were selected.In the positioning algorithm of the femoral shaft anatomy axis,the random sampling consensus algorithm and the least square method were used as the The fitting algorithm is compared,and it is concluded that the effect of using the random sampling consensus algorithm is better.At the same time,in the random sampling consensus algorithm,different parameters are selected for comparison experiments,and the best parameter selection is obtained.Prove the effectiveness of the image preprocessing,femoral shaft anatomical axis positioning algorithm and femoral neck anatomical axis positioning algorithm in this subject.