A Preliminary Study Of DCE-MRI In The Evaluation Of Blood Supply Of Femoral Head Before And After Internal Fixation Of Femoral Neck Fracture

Purpose: This study hopes to evaluate the blood supply of the femoral head through dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI),as well as the internal fixation of femoral neck fractures with cannulated screws and the hip joint capsule incision and decompression femoral head drilling to evaluate the femoral neck fractures.The blood supply of the residual femoral head,and track the changes and prognosis of the femoral head microcirculation after internal fixation,explore the value and accuracy of DCE-MRI in the evaluation of the blood supply of the femoral head,and hope that it can guide clinicians in patients with femoral neck fractures Choice of treatment plan and prediction of prognosis.Methods: Prospectively collect the data of patients diagnosed with unilateral femoral neck fracture by X-ray or CT from June 2019 to July 2020 in our hospital.DCE-MRI was performed before operation,5-7 days after operation,and 3 months after operation.Intraoperative cannulated screw internal fixation and hip capsulectomy and decompression of femoral head drilling were performed.A 1cm region of interest(ROI)was drawn on the femoral head through the DCE-MRI computer software and converted into a percentage time signal intensity curve(TIC%),and make the following comparisons: 1.Before surgery,the upper inner quadrant,outer upper quadrant of the healthy side and the affected side of the femoral head,and the entire femoral head area ROI,the first enhancement peak(fEmax),the maximum enhancement peak(Emax)on the TIC%,Time to peak(TTP)between the 3groups of parameters;2.After the operation,the contralateral and the affected side of the femoral head inner upper quadrant,outer upper quadrant ROI,TIC% upper fEmax,Emax,TTP 3 group parameters difference;3.Comparison of the same side Femoral head area(inner upper quadrant,outer upper quadrant ROI)at different time points before operation,5-7 days after operation,and 3 months after operation TIC% fEmax,Emax,TTP parameters difference.4.Analyze the relationship between the results of DCE-MRI blood supply detection and the results of intraoperative drilling to detect the blood supply of the femoral head.5.Analyze the relationship between DCE-MRI blood supply test results and fracture types.Results: A total of 11 cases were collected,including 7 males and 4 females;the average age was 42 years;1 case was Grand II,6 cases were type III,and 4 cases were type IV.The average follow-up time was 11 months(8-15 months).).Comparison results of DCE-MRI parameters: The Emax values of the entire femoral head of the healthy side and the affected side of the patients before surgery were statistically different between the two groups(mean paired difference=3.50273;P<0.05).The patients on the healthy side and the affected side were 3 months after the operation.There was a statistical difference in the Emax value of the upper inner quadrant between the two groups(mean paired difference=0.17182;P<0.05);there was a statistical difference in the fEmax of the entire femoral head of the healthy side and the affected side before the operation(average paired difference)Value=4.19909;P<0.05).There was a statistically significant difference in fEmax between the healthy side and the upper outer quadrant of the affected side at 3 months after the operation(mean paired difference=0.32273;P<0.05).The patient was healthy at 3 months after the operation.The fEmax of the inner and upper quadrants of the side and the affected side was statistically different between the two groups(average of paired difference=0.20636;P<0.05);the whole femoral head of the healthy side and the affected side before operation(average of paired difference=-1.34909);Before the operation,the healthy side and the affected side’s upper outer quadrant(average of paired difference =-1.22364);before the operation,the healthy side and the affected side of the inner upper quadrant(average of paired difference =-1.6345),the TTP value has statistics between the two groups Differences in science(P<0.05);the same ROI in the upper outer quadrant of the affected side before and after the comparison:only the peak time value is 3-5 days after the operation(2.53±0.61),3 months after the operation(1.37±0.38)and before the operation(1.36±0.2)There was a statistical difference(P<0.05),and there was no statistical significance among the remaining groups after the operation.Comparison of the same ROI in the upper and inner quadrant of the affected side before and after the same time: only the peak time value is 3-5 days after operation(1.48±0.58),3 months after operation(1.36±0.27)and preoperative(2.86±0.6)are statistically different(P<0.05);there was no statistical significance among the other groups.There was no statistical difference between the results of DCE-MRI blood supply detection and the blood supply detection results of hip joint capsule incision and decompression femoral head drilling(P>0.05).There was no statistically significant difference between the Garden classification and the correlation analysis of the patient’s blood supply test results(P>0.05).Conclusion: 1.DCE-MRI can not only accurately assess the blood supply of the femoral head after femoral head fracture,but also evaluate the local area perfusion of the femoral head after surgery and predict the prognosis.It is currently the most promising technique that is widely used in clinical practice.2.DCE-MRI combined with hip joint capsule incision and decompression femoral head drilling can more accurately assess the blood supply and perfusion of the femoral head after femoral neck fracture.