Objective To investigate the application value of conventional MRI combined with diffusion tensor imaging(DTI)in evaluating the correlation between the texture composition of benign prostatic hyperplasia(BPH)and the International Prostate Symptom Score(IPSS).Methods Seventy patients with BPH confirmed by pathology were retrospectively analyzed and all patients underwent conventional MRI,DTI and IPSS before surgery.Evaluation metrics included:the mean signal intensity of T2WI(mean-SI-T2WI),apparent diffusion coefficient(ADC)and fractional anisotropy(FA)values.Independent samples t-test,partial correlation analysis,and receiver operating characteristic(ROC)curve were used to assess the correlation between the texture parameters of the prostate transition zone and IPSS.Results The mean-SI-T2WI was significantly negatively correlated with IPSS(r=-0.683,P<0.001);the average ADC value was slightly negatively correlated with IPSS(r=-0.467,P<0.001);and the average FA value was slightly positively correlated with IPSS(r=0.419,P<0.001).The predictive value of MRI texture parameters for IPSS in BPH patients,ranked from high to low,mean-SI-T2WI[area under the curve(AUC)=0.734],average ADC value(AUC=0.673),and average FA value(AUC=0.635);However,the combination of mean-SI-T2WI+ADC+FA(AUC=0.791)did not significantly improve the diagnostic efficacy by DeLong's test(P>0.05).Conclusion Mean-SI-T2WI,DWI and DTI can be used to evaluate the composition of the prostate,among which mean-SI-T2WI is the best,and the com-bination of them can not improve the diagnostic efficacy.

Objective To investigate the application value of conventional MRI combined with diffusion tensor imaging(DTI)in evaluating the correlation between the texture composition of benign prostatic hyperplasia(BPH)and the International Prostate Symptom Score(IPSS).Methods Seventy patients with BPH confirmed by pathology were retrospectively analyzed and all patients underwent conventional MRI,DTI and IPSS before surgery.Evaluation metrics included:the mean signal intensity of T2WI(mean-SI-T2WI),apparent diffusion coefficient(ADC)and fractional anisotropy(FA)values.Independent samples t-test,partial correlation analysis,and receiver operating characteristic(ROC)curve were used to assess the correlation between the texture parameters of the prostate transition zone and IPSS.Results The mean-SI-T2WI was significantly negatively correlated with IPSS(r=-0.683,P<0.001);the average ADC value was slightly negatively correlated with IPSS(r=-0.467,P<0.001);and the average FA value was slightly positively correlated with IPSS(r=0.419,P<0.001).The predictive value of MRI texture parameters for IPSS in BPH patients,ranked from high to low,mean-SI-T2WI[area under the curve(AUC)=0.734],average ADC value(AUC=0.673),and average FA value(AUC=0.635);However,the combination of mean-SI-T2WI+ADC+FA(AUC=0.791)did not significantly improve the diagnostic efficacy by DeLong's test(P>0.05).Conclusion Mean-SI-T2WI,DWI and DTI can be used to evaluate the composition of the prostate,among which mean-SI-T2WI is the best,and the com-bination of them can not improve the diagnostic efficacy.

Objective To generate and identify the Itgbl1(integrin beta-like)promoter-driven Cre knock-in mouse line.Methods Itgbll-Cre knock-in mice were generated using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)gene editing.The Itgbl1-Cre mice were crossed with the Cre reporter ROSALSL-tdTomato)mice to detect the expression profile of Cre activity.The tdTomato expression pattern across tissues and cell-specific markers were used to identify the cell types of Itgbl1-expressing cells and their progeny.Results and Conclusion tdTomato was specifically expressed in mucous acinar cells of the sublingual gland,pancreatic islet cells,and gastric endocrine cells.In addition,tdTomato expression was also found in some of the neurons of the retina and brain,as well as in a few cells in the serosal layer of the intestine,articular cartilage,periosteum,and bone marrow.The first Itgbl1-Cre recombinase transgenic mouse line was established,which can specifically label the mucous acinar cells of the sublingual gland.

Objective To compare the clinical efficacy of anteroposterior approach (APA) versus anterior approach (AA) for decompression,fusion and fixation for single-level unstable thoracolumbar vertebrae fractures concomitant with incomplete neurologic symptoms and injury to posterior ligament complex (PLC).Methods From February 2006 to June 2012,55 patients were treated for single-level unstable thoracolumbar vertebrae fractures.Of them,27 were treated by only anterior decompression and lateral screw-rod instrumentation and 28 by anterior decompression and fusion combined with open posterior pedicle fixation of one to two segments above and below the fracture position.The 2 groups were compared at postoperative 3 and 12 months in terms of visual analogue scale (VAS),overall score of short-form health survey (SF-36),Japanese Orthopaedics Association (JOA) score of lower back,Oswestry disability index (ODI),loss ratio of anterior margin of vertebral height,endplate angle of kyphotic deformity of superior-inferior adjacent vertebrae,wedge angle of fractured vertebra via radiographic measurement and canal compromise rate.The neurologic functional recovery was analyzed using the American Spine Injury Association (ASIA) evaluation system at postoperative 12 months.Results There were no significant differcnces in operative time,amount of blood loss or postoperative drainage between the 2 groups (P ＞ 0.05).At postoperative 3 months,the VAS and JOA scores in the APA group were significantly better than those in the AA group (P ＜ 0.05).At 12 months after surgery,the VAS,kyphotic angle of adjacent vertebra,wedge angle of fractured vertebra and the ASIA improvements in the APA group were significantly better than those in the AA group (P ＜ 0.05).There were no significant differences between the 2 groups in the other indexes at postoperative 3 or 12 months (P ＞ 0.05).All the comparative indexes were significantly improved than the preoperative values in all the patients in the 2 groups at both 3 and 12 months (P ＜ 0.05).Conclusions Compared with the merely anterior approach,the combined antero-posterior approach may have advantages of better immediate and persistent reduction,steadily rebuilding fractured alignment,continuously maintaining injured biomechanical stability,and obviously improving neurological function.As the antero-posterior approach allows for combination of posterior auxiliary reduction and fixation with anterior definitive support and decompression,it may lead to a safe and effective treatment of unstable single-level thoracolumbar fracture concomitant with incomplete neurologic and PLC impairments.

Objective To investigate the clinical efficacy of anterior pelvic plating plus percutaneous lumbo-iliac rod/screw fixation in the treatment of pelvic fractures which are vertically and rotationally unstable and combined with unilateral sacral fracture of Denis type Ⅱ.Methods From January 2008 to November 2012,19 patients were treated for compound injury to the anterior and posterior pelvic rings complicated with sacral fracture of unilateral Denis type Ⅱ using anterior pelvic plating plus posterior percutaneous fixation of lumbo-ilium with screws.Their improvement in neurological function,reduction outcome and clinical effectiveness were evaluated by comparing preoperation and 2 years postoperation in terms of visual analogue scale (VAS),Japanese Orthopaedic Association (JOA) score for lower back pain,MOS Item Short-form health survey (SF-36 comprehensive scale),modified Roland-Morris Disability questionnaire (RDQ),Oswestry disability index (ODI),Gibbons overall scale,Majeed total score,sacral kyphosis abnormity,bias of sagittal/coronal vertical axis (SVA/CVA),pelvic incidence,pelvic tilt,lumbar lordosis,vertical displace,and leg length discrepancy.Results The differences respectively reached statistical significance for the aforementioned clinical and imaging parameters between preoperation and 2 years postoperation (P ＜ 0.05).By Majeed scoring,13 cases were rated as excellent,4 as good and 2 as fair.By Tometta/Matto scoring postoperatively,the fracture reduction was rated as excellent in 12 cases,as good in 6 and as fair in one.The complications of incision infection or necrosis,secondary neurovascular damage,implant failure or mal-union was not observed.Perfect nerve functional recovery and sufficient imaging reduction were achieved in all but one patient who had to receive decompression and release for sacral canals or foramens.According to Mohammad criteria,15 patients were engaged in the jobs with the same intensity and property as their pre-injury ones.Conclusions The simultaneous hybrid performance of anterior reconstruction plating combined with unilateral lumbar/sacral pedicle and iliac screwing may be a safe,reliable and satisfactory treatment for pelvic fractures of AO/Tile C1 type which involve unilateral sacral Denis type Ⅱ.

Objective To explore the effect of MI-TLIF under expansion channel combined with pedicle screw fixation on treatment of patients with lumbar degenerative scoliosis complicated with spinal stenosis.Methods A total of 51 patients with lumbar degenerative scoliosis complicated with spinal stenosis were selected and divided into observation group (n =28) and control group (n =23).The control group was treated with TLIF combined with pedicle screw fixation,and the observation group was treated with MI-TLIF and pedicle screw internal fixation under the expansion channel.Clinical efficacy and low back pain were compared between two groups.Results The incision length,intra-operative blood loss,postoperative drainage volume,postoperative time and hospital stay in the observation group were significantly better than those in the control group,and the operation time was significantly longer than the control group (P ＜ 0.05).The VAS score and ODI score of the observation group were significantly lower than those of the control group (P ＜ 0.05).The bone graft fusion rate after one year was 92.86％ in the observation group,which was slightly higher than 86.96％ in the control group (P ＞ 0.05).There were no serious complications in the two groups.Conclusion In the treatment of patients with lumbar degenerative scoliosis complicated with spinal stenosis,the clinical efficacy of MI-TLIF assisted with pedicle screw fixation under expansion channel is equivalent to traditional TLIF.

Objective To explore the effect of MI-TLIF under expansion channel combined with pedicle screw fixation on treatment of patients with lumbar degenerative scoliosis complicated with spinal stenosis.Methods A total of 51 patients with lumbar degenerative scoliosis complicated with spinal stenosis were selected and divided into observation group (n =28) and control group (n =23).The control group was treated with TLIF combined with pedicle screw fixation,and the observation group was treated with MI-TLIF and pedicle screw internal fixation under the expansion channel.Clinical efficacy and low back pain were compared between two groups.Results The incision length,intra-operative blood loss,postoperative drainage volume,postoperative time and hospital stay in the observation group were significantly better than those in the control group,and the operation time was significantly longer than the control group (P ＜ 0.05).The VAS score and ODI score of the observation group were significantly lower than those of the control group (P ＜ 0.05).The bone graft fusion rate after one year was 92.86％ in the observation group,which was slightly higher than 86.96％ in the control group (P ＞ 0.05).There were no serious complications in the two groups.Conclusion In the treatment of patients with lumbar degenerative scoliosis complicated with spinal stenosis,the clinical efficacy of MI-TLIF assisted with pedicle screw fixation under expansion channel is equivalent to traditional TLIF.

Objective To verify the daily delivery accuracy of volumetric-modulated arc therapy (VMAT) and achieve the process quality control (PQC) of linac using statistical process control (SPC)technology.Methods The log files of all treatments were taken out from the linac system.An in-house software which created by Matlab 7.14 was used to analyze the daily parameters accuracy and the mechanism and dose delivery accuracy of the linac for each VMAT,and an daily evaluation report was automatically created for the linac.The stability of the linac and the deviation of the delivery accuracy for various cancer sites were also analyzed.To achieve the process quality control of hnac using SPC technology,the control limit of each parameter was calculated by Johnson alternation and the single value control charts were drawn.Results 76 patients mainly with nasopharyngeal carcinoma,cervical carcinoma,rectal cancer and laryngeal cancer,got the treatment daily with VMAT technology,and a total of 2 446 arcs were delivered by the linac in continuous 16 days.The gantry angle error,y and x collimator position error,MLC leaf position error and dose delivery error were 0.49°,0.09 mm,0.38 mm,0.31 mm,0.05 MU,respectively.Compare to the nasopharynx,uteri,rectal and larynx cancer,it can be seen that the variation factors of dose delivery and gantry angle errors for various cancer sites were higher,which was 8.10％ and 4.54％,respectively.Through the process quality control of the linac,it was found that all the parameters were in control.While some abnormal points arose (the error was greater than UCL),and the ratio of the gantry angle which was out of control (0.45％) was the highest in all parameters.Conclusions linac delivery accuracy could be monitored and verified during the whole VMAT treatment for each patient,and the daily running condition of linac could be monitored.Through the introduction of SPC technology and the control charts,the process quality control of linac in VMAT could be achieved.It is a financial and valid method for the daily quality assurance of linac.

Objective To evaluate the image quality and registration accuracy of a three?dimensional ( 3D ) dynamic phantom in four?dimensional computed tomography ( 4DCT ) and four?dimensional cone?beam computed tomography ( 4DCBCT) . Methods The Computerized Imaging Reference Systems Dynamic Thorax Phantom Model 008A was scanned to get 4DCT and 4DCBCT images. Two balls with different diameters ( ?= 1 cm and ?= 2 cm) were used to simulate tumors with different sizes. The motion mode of the balls was 3D sinusoidal motion at 0?25 Hz ( the amplitudes along the x, y, and z axes were ±1?0 cm, ±0?4 cm, and ±0?2 cm, respectively). Gross target volumes (GTVs) from 10?phase bins, internal gross target volumes (IGTV), and target volumes on maximum intensity projection (MIP) and mean intensity projection (MeanIP) images were contoured and calculated. Target volumes on 4DCT or 4DCBCT images were compared with the static and dynamic volumes of the balls ( VS and VD ) . The matching index ( MI) of target volumes between the 4DCT and 4DCBCT images was analyzed after rigid image registration. Results The GTV in each phase of the image was larger than VS . The difference between the average GTV derived from 10 phases of 4DCT or 4DCBCT images and Vs of the small ball was larger than that of the large ball ( 35?03% vs. 22?66%;32?62% vs. 17?00%) . All the IGTVs and target volumes on MIP images were slightly larger than VD , but target volumes on MeanIP images were smaller than VD . The average MI of 10?phase bins of the small ball was smaller than that of the large ball ( 66?76% vs. 82?21%) . Moreover, MIs of IGTV,MIP, and MeanIP of the small ball were also smaller than those of the large ball ( 77?39% vs. 90?29%;75?90% vs. 89?28%;74?47% vs. 82?74%) . Conclusions In the case of a relatively small tumor volume and a relatively large motion amplitude, 4DCT and 4DCBCT should be used with caution for comparison of image registration.

Objective To study CT numbers correction of kilo?voltage cone?beam CT (KV?CBCT) images for dose calculation. Method Aligning the CBCT images with plan CT images, then obtain the background scatter by subtracting CT images from CBCT images. The background scatter is then processed by low?pass filter. The final CBCT images are acquired by subtracting the background scatter from the raw CBCT. KV?CBCT images of Catphan600 phantom and four patients with pelvic tumors were obtained with the linac?integrated CBCT system. The CBCT images were modified to correct the CT numbers. Finally, compare HU numbers between corrected CBCT and planning CT by paired T test. Evaluate the image quality and accuracy of dose calculation of the modified CBCT images. Results The proposed method reduces the artifacts of CBCT images significantly. The differences of CT numbers were 232 HU, 89 HU, 29 HU and 66 HU for air, fat, muscle and femoral head between CT and CBCT respectively (P= 0?? 39,0?? 66,0?? 59,1).The differences of CT numbers between CT and CBCT was reduced to within 5 HU. And the error of dose calculation with corrected CBCT images was within 2%. Conclusions The CT numbers of corrected CBCT are similar with plan CT images and dose calculations based on the modified CBCT show good agreement with plan CT.