Heart failure is a fatal stage of end-stage cardiovascular disease,which brings a huge medical burden to the society because of its high mortality and re-hospitalisation rates.Intestinal microecology is the largest and most com-plex microecosystem of human body.It is inhabited by tens of thousands of microorganisms in human gastrointestinal tract.In recent years,with the deepening of the study of intestinal flora,more and more studies have found that the im-balance of intestinal microecology can cause changes of metabolites in heart failure patients,which is one of the key triggers for the development of heart failure,therefore,using the intestinal microbial homeostasis as a new entry point for the treat-ment of heart failure will be a hotspot in medical research.However,the theory of Chinese medicine,"the spleen is the guardian",covers the physiological functions of the spleen,such as the spleen's main function of transporting,spleen's main function of ascending and clearing,and its main function of hiding camping,etc.,and the functions of intestinal flora and the"spleen is the guardian"are similar to a certain extent.Therefore,this paper starts from a holistic viewpoint and takes the theory of"spleen as the guardian"in Chinese medicine as an entry point to elaborate on the pathogenesis of intes-tinal microecological imbalance and heart failure,so as to provide a reference for Chinese medicine treatment or drug re-search.

Objective To establish a novel clinical application process of the optical surface monitoring system(OSMS)guided volumetric modulated arc therapy(VMAT)for total body irradiation(TBI),and to assess the accuracy and effectiveness of OSMS in inter-fractional auxiliary positioning before radiotherapy and real-time monitoring of intra-fractional motion during radiotherapy.Methods A retrospective analysis was conducted on 15 leukemia patients who underwent OSMS-guided VMAT-TBI before hematopoietic stem cell transplantation.CT simulation positioning was performed,and the whole-body image data which were collected in head-first supine position(HFS)and feet-first supine position(FFS)were transmitted to the treatment planning system for image registration,multicenter VMAT planning and dose verification.The prescription dose was 800 cGy in 4 fractions twice daily.OSMS was used to assist positioning before delivery,and CBCT was used for position verification.During treatment,OSMS was used for monitoring.The intra-fractional error monitored by OSMS in real time was obtained by analyzing the offline log files.Results The mean dose and coverage of the target area in HFS plan were(905.4±19.0)cGy and 93.0%±2.8%.The mean doses to lung and kidney were(603.7±55.7)cGy and(600.4±49.6)cGy,respectively,and the maximum dose to the lens was(393.9±58.9)cGy.The mean dose and coverage of the target area in FFS plan were(888.5±58.9)cGy and 94.0%±3.2%;and the maximum dose at the junction was(1148.9±72.9)cGy.Fractional treatment delivery time was(75.1±15.1)min.OSMS-assisted positioning was carried out before delivery,and the total deviations of CBCT three-dimensional vector in translational and rotation directions were(2.71±1.96)mm and 0.91°±0.90°,respectively.The three-dimensional vector deviation of the intra-fractional motion amplitude in translational direction monitored by OSMS during the treatment was(1.95±1.88)mm,of which the deviation within 1 mm accounted for 57.5%,79.7%and 62.1%in longitudinal,lateral and vertical directions,respectively.The three-dimensional vector deviation in rotation direction was 0.76°±0.72°,of which the deviation within 1°accounted for 93.1%,85.7%and 94.3%in rotation,pitch and roll directions,respectively.Conclusion VMAT simplifies TBI process,while improving target coverage and organs-at-risk sparing.The use of OSMS can reduce positioning errors,especially rotation errors.In order to ensure the accurate implementation of TBI and the safety of patients,it is necessary to use OSMS for auxiliary positioning and intra-fractional position monitoring.

Objective:To investigate the protection of Active Breathing Coordinator(ABC)technique for heart and its substructures in radiotherapy for left breast cancer.Methods:A total of 50 patients with left breast cancer who underwent radiotherapy in our department were retrospectively selected,and treatment plans with intensity modulated radiotherapy(IMRT)were designed on the images of ABC combined with deep inspiration breath hold(ABC-DIBH)computed tomography(CT)and free-breathing(FB)CT,respectively.The dose parameters of the organ at risks(OARs)of heart and its substructures,including left ventricle(LV),left atrium(LA),right ventricle(RV),right atrium(RA),left main coronary artery(LMCA),left anterior descending coronary artery(LAD),left circumflex coronary artery(LCX)and right coronary artery(RCA),were compared between the two conditions.Results:Compared with FB,the dose of 2%volume(D2),the mean dose(Dmean),the percent volumes covered by different doses(V30,V20,V10,V5)decreased respectively 32.91%(absolute reduction of 1279.11 cGy),36.12%(195.94cGy),58.95%(2.8%),54.32%(3.58%),50.14%(5.56%)and 46.22%(9.67%)of heart under ABC-DIBH condition,and the differences were significant(t=10.28,12.81,9.16,10.28,12.82,12.24,P＜0.01),respectively.In addition,the Dmean values of LV,LA,RV,RA,LMCA,LAD,LCX and RCA decreased by 37.64%(absolute reduction was 285.92 cGy),15.38%(23.68 cGy),34.12%(118.93cGy),9.72%(12.52 cGy),22.17%(47.99 cGy),31.81%(820.63 cGy),16.51%(34.72 cGy)and 14.86%(34.11cGy)under ABC-DIBH condition,respectively,the differences were significant(t=9.50,3.71,6.20,8.65,3.18,10.92,4.26,6.71,P＜0.05).Conclusion:ABC technique can greatly reduce the received doses of heart and its substructures by extending the distance between the heart and the target region with DIBH,thus can form a very effective protection for the heart and its substructures.In addition,it can eliminate the dynamic variation of target location of breast cancer caused by respiratory,and avoid a series of problems,such as target missing,overexposure on normal tissue,and dose deviation.

Objective:To compare the dosimetric differences between active breathing coordinator (ABC) and Catalyst for respiratory gating after breast conserving surgery for left breast cancer.Methods:Data of 48 female patients with left breast cancer after breast conserving surgery admitted to the Radiotherapy Department of Shenzhen People′s Hospital from November 2020 to August 2021 were retrospectively selected. They were randomized to receive dynamic intensity modulated radiotherapy (IMRT) plans with ABC or Catalyst. The dosimetric differences in targets and organs at risk between the two groups were analyzed.Results:Comparison of the two respiratory gating IMRT plans revealed no statistically significant differences ( P > 0.05) in D90%, D98%, Dmax, Dmean, conformity index (CI), homogeneity index (HI), and monitor unit parameters in the target volume, (i.e., chest wall), as well as the ipsilateral lung and heart under the deep inhalation breath hold (DIBH) mode. The Dmean, Dmax, and D2% of the left anterior descending coronary artery (LAD) in the Catalyst group were better than those in the ABC group [(1 047.72 ± 1 401.84) vs. (454.48 ± 206.26), (1 619.28 ± 809.05) vs.(1 068.53 ± 419.63), (1 405.85 ± 798.30) vs. (1 016.54 ± 592.00) cGy], with statistically significant differences ( t= -2.07, -3.18, -2.07, P<0.05). Conclusions:Both ABC and Catalyst respiratory gating systems meet the requirements for clinical treatment, with the latter more effective in reducing the exposure dose of LAD.

Objective:To compare translational and rotational setup errors between immobilization with open masks combined with positioning with the optical surface monitoring system (OSMS) and immobilization with full masks combined with positioning with laser lights and mask markers, find the advantages of open masks combined with OSMS in hypofractionated stereotactic radiotherapy (HSRT) for brain metastases, and calculate planning target volume (PTV) expansions with different immobilization and positioning method for patients with brain metastases.Methods:The setup data of 55 patients with brain metastases who received HSRT were analyzed retrospectively. According to immobilization and positioning method, the patients were divided into group A (OSMS + open masks), group B1 (full head-neck-shoulders masks + polyurethane foam cushions), and group B2 (full head-neck-shoulders masks + standard headrests). Positioning was directed by automatic couch motion in OSMS in group A and by laser lights and mask markers in groups B1 and B2. Cone beam computed tomography (CBCT) scans were registered using the bone registration method to obtain setup errors in six directions ( x, y, z, roll, pitch, yaw). PTV expansions were calculated according to the van Herk formula. Results:A total of 288 sets of CBCT registration data were acquired. Among three groups, group A showed the smallest mean setup errors and 3D vector error, which were (0.47±0.33) mm, (0.49±0.31) mm, (0.44±0.31) mm, (0.42±0.32)°, (0.48±0.31)°, (0.42±0.22)°, and (0.90±0.39) mm, respectively. Group A differed significantly from group B1 and group B2 in the errors at all directions ( P < 0.05) except for the yaw direction compared with group B1 ( P > 0.05). Group A had no setup error ≥2 mm in translational directions or ≥2° in rotational directions. Group B1 showed significantly smaller setup errors in the y, z, and yaw directions and 3D vector error than group B2 ( P < 0.05). In group A, PTV expansions in three directions ( x, y, and z) were 1.32, 1.19, and 1.22 mm, respectively, which were smaller than those of the other two groups. Conclusions:In HSRT for patient with brain metastases, compared with full head-neck-shoulders masks combined with laser lights and mask markers, open masks combined with OSMS can significantly improve setup precision in six directions and reduce repeated setup and PTV expansions, which shows promise for clinical application.

Objective:To study the impact of the Varian real-time position management (RPM) respiratory gating system on radiotherapy planning dosimetry.Methods:The radiotherapy plans of 40 cases with thoracic or abdominal tumors were retrospectively selected in this study. The motion phantom for quality control was adopted to generate respiratory gating signals, and the 30%-60% stable phase at the end of expiratory was selected as the respiratory gating window. The dose verification for the abovementioned radiotherapy plans was performed using the Portal Dosimetry (PD) system under RPM respiratory gating mode with the Edge accelerator. Afterwards, dose analysis was performed with different γ passing rate criteria and the distribution characteristics of γ values were analyzed. Finally, the verification results between the non-gating mode and the gating mode were compared.Results:Under the respiratory gating mode, the passing rates of all intensity-modulated radiation therapy/volumetric-modulated arc therapy (IMRT/VMAT) plans with or without flattening filters were over 95.5% by γ criteria of (3%, 3 mm) or (3%, 2 mm) and were over 90% by stricter γ criteria of (2%, 2 mm). All plans met the clinical requirements recommended by the American Association of Physicists in Medicine (AAPM). The passing rates of dose verification under non-gating mode were slightly better than those under respiratory gating mode, and the differences between the two modes were statistically significant (3%/3 mm, Z =-1.45; 3%/2 mm, Z =-2.86; 2%/2 mm, Z =-3.70; 1%/1 mm, Z =-4.52; P<0.05). There was no significant difference in the minimum and maximum values of γ and the share of γ > 1.5 of plan verification result under the two modes. However, the average value and standard deviation of the γ were generally smaller under the non-gating mode. Conclusions:The impact of the introduction of RPM respiratory gating technology on dose is clinically acceptable, and the execution of these plans in this gating mode is safe and reliable.

Objective:To compare the dosimetric differences between volumetric-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT) on planning target volume (PTV) and organ-at-risk (OAR) for breast cancer after modified radical mastectomy, aiming to provide evidence-based reference for clinical practice.Methods:According to strict inclusion and exclusion criteria, literature search was performed in PubMed, Cochrane Library, FMRS, CNKI, Wanfang Data and VIP full text databases from the inception of databases up to March 2020. The controlled clinical trials of dosimetric comparison between VMAT and IMRT for breast cancer following modified radical mastectomy were selected. The meta-analysis was performed using Stata14 software.Results:The meta-analysis included 281 patients from 13 observational studies. Compared with IMRT, VMAT significantly increased the PTV dose coverage D 95%( P<0.001) and significantly improved the PTV homogeneity index (HI, P<0.001) and conformity index (CI, P=0.004). Compared with IMRT, VMAT more effectively decreased the ipsilateral lung V 20Gy (WMD=1.332, P=0.027) and contralateral lung V 10Gy ( P=0.003). There were no significant differences in theD mean, V 5Gy, V 10Gy and V 30Gy of the ipsilateral lung, D mean and V 5Gy of the contralateral lung, D mean, V 10Gy and V 30Gy of the heart between VMAT and IMRT (all P>0.05). Compared with VMAT, IMRT reduced the cardiac V 5Gy ( P=0.001). However, sensitivity analysis of included literature on cardiac V 5Gy showed that the P value was reversed, indicating that the stability of the results was poor. VMAT significantly shortened the delivery time ( P<0.001) and the number of monitor units ( P<0.001) compared to IMRT. Conclusion:Compared with IMRT, VMAT can achieves superior target dose coverage, HI and CI, better protection for the ipsilateral and contralateral lung, fewer monitor units and shorter delivery time.

Objective:To compare the clinical effect of Ilizarov frame and unilateral frame in the treatment of tibial segmental bone defect combined with soft tissue defect by open bone transport.Methods:A retrospective case-control study was conducted to analyze the clinical data of 32 patients with tibial segmental bone defect and soft tissue defect-up who underwent open bone transport technique in Tianjin Hospital from August 2008 to August 2016 and obtained complete followed-up. There were 22 males and 10 females, aged 22-64 years (mean, 36.8 years). Nineteen patients in the Ilizarov group showed the mean bone defect length of 7.9 cm and mean soft tissue defect area of 41.4 cm 2. Thirteen patients in the unilateral group showed the mean bone defect length of 7.8 cm and the mean soft tissue defect area of 39.2 cm 2. The results of fracture healing, wound healing time, radiological consolidation index, external fixation index, Association for the Study and Application of the Method of Ilizarov (ASAMI) bone and lower-limb function score and incidence of complications were compared between the groups. Results:All patients were followed up for 24 to 60 months [(32.6±1.3)months]. Bone healing was achieved in all patients. The wound healing time was (2.7±2.3)days in Ilizarov group and (2.4±1.8)days in unilateral group ( P>0.05). The consolidation index was (43.4±8.7)d/cm in Ilizarov group and (45.8±10.3)d/cm in unilateral group ( P>0.05). The external fixation index was (52.6±8.9)d/cm in Ilizarov group and (58.7±12.9)d/cm in unilateral group ( P<0.05). The results of ASAMI bone score was excellent in 10 patients, good in 6, fair in 2 and poor in 1 in Ilizarov group, with the excellent rate of 84%; and excellent in 6 patients, good in 4, fair in 2, and poor in 1 in unilateral group, with the excellent rate of 77%, with insignificant difference between two groups ( P>0.05). The results of ASAMI lower-limb function score was excellent in 8 patients, good in 7, fair in 3, poor in 1 in Ilizarov group, with the excellent rate of 79%; and excellent in 6, good in 3, fair in 3, poor in 1 in unilateral group, with the excellent rate of 69%, with insignificant difference between the two groups ( P>0.05). Incidence of axial deviation was zero in Ilizarov group versus 23% in unilateral group ( P<0.05). After operation, Ilizarov group had refracture in 1 patient and pin site infection in 5, and unilateral group had refracture in 1 patient and pin site infection in 1, showing no significant difference between the two groups ( P>0.05). Conclusions:Tibial segmental bone defect with soft tissue defect can be effectively treated by open bone transport with Ilizarov and unilateral frame. Ilizarov frame has better biomechanical properties and is more convenient for correction of poor postoperative axial alignment.

Objective:To investigate the accuracy and postoperative efficacy of fluoroscopy and CT in measuring the mounting parameters of Taylor Spatial Frame.Methods:Data of patients with peripheral knee deformities who were treated by Taylor Spatial Frame from June 2006 to December 2017 were retrospectively analyzed. According to different measurement methods of mounting parameters, they were divided into fluoroscopy group (mounting parameters were obtained by intraoperative fluoroscopy) and CT group (mounting parameters were obtained by postoperative CT). There were 33 patients (35 segments) in the fluoroscopy group, 23 males (23 segments) and 10 females (12 segments), with an average age of 36.4±11.6 years old. In CT group, there were 30 patients, 19 males and 11 females, with an average age of 36.9±13.8 years. There were 22 cases (24 segments) of high tibial osteotomy, 5 cases (5 segments) of distal femur osteotomy, and 6 cases (6 segments) of both distal femur and high tibial osteotomy. Operation time, external fixation time, the number of electronic prescription and deformity correction time, mechanical axis deviation (MAD), medial proximal tibia angle (MPTA), mechanical lateral distal femoral angle (mLDFA), range of motion (ROM) andhospital for special surgery (HSS) knee functional scores were compared between the two groups.Results:All the 63 patients were followed up for 21.9 months (range, 12-60 months). In fluoroscopy group, operating time was 100.9±9.1 min, electronic prescription number 1.4±0.6, and deformity correction time was 19.4±3.6 days. In CT group, operating time was 79.2±10.8 min, electronic prescription number 1.2±0.4, and deformity correction time was 16.0±4.4 days. The difference of the above indexes between the two groups was statistically significant ( t=8.803, 2.042, 3.440, all P < 0.05). In the fluoroscopy group, the external fixation time was 4.8±0.9 months; MAD was 4.3±2.1 mm; MPTA was 88.5°±1.9°; mLDFA was knee 89.2°; ROM was 122.4°±3.9° and HSS score was 90.0±3.6. In CT group, the external fixation time was 4.6±0.9 months; MAD was 4.0±1.9 mm; MPTA was 87.8°±1.7°; mLDFA was knee 88.6°; ROM was 122.7°±3.4° and HSS score was 91.1±2.9. There was no statistically significant difference in the above indexes between the two groups (all P >0.05). In the fluoroscopy group, 22 segmental deformities were corrected by one electronic prescription, and 13 segmental deformities were corrected by two or more electronic prescriptions. In CT group, 25 segmental deformities were corrected by one electronic prescription, and 5 segmental deformities were corrected by two electronic prescriptions. There was no incision infection and no neurovascular injury in the two groups. Conclusion:Both fluoroscopy and CT scan can obtain the mounting parameters of the Taylor Spatial Frame, and the results of correction of the peripheral deformities of the knee joint are satisfactory. However, CT measurement of the mounting parameters is more accurate which could achieve shorter operation time, and less times of electronic prescriptions.

Objective To evaluate the clinical outcomes and correction accuracy of deformities around the knee joint using external fixator-assisted internal fixation (FAIF).Methods From January 2014 to March 2018,data of 15 patients (17 bone segments) with deformities around the knee joint who had been corrected with external fixator-assisted internal fixation were retrospectively analyzed.There were 6 males and 9 females,with an average age of 39 years (range,21-60 years).There were 9 patients with genu varus and 6 with genu valgus.All the 15 patients had shortening ranging from 5 to 22 mm,with an average of 12 mm.Unilateral external fixator was used to stabilize the osteotomy site intraoperatively until the satisfied mechanical axis was acquired.Then the plate or Intramedullary nail was inserted and fixed,the external fixator was removed after internal fixation.Results Femur osteotomy was done in 7 patients and tibia osteotomy was done in 6 patients,while 2 patients had osteotomy in both tibia and femur.Intramedullary nailing was used in 2 bone segments,and plate was used in 15 bone segments.The correction of angle ranged from 7° to 22°,with an average of 12.5°.The correction of the 9 cases of genua varus ranged from 10° to 22°,with an average of 17.6°.The correction of the 6 cases of genu valgum ranged from 7° to 13°,with an average of 10.4°.The mean time to achieve union of the osteotomy sites was 3.5 months (range,2.5-5.0 months).All the 15 patients were followed up for 8-48 months (average,23 months).The mechanical axis deviation (MAD) was 5.93 mm (range,0-15 mm) after operation which was 34.8 mm (range,8-55 mm) before operation.The mean post-operative mechanical lateral distal femoral angle (mLDFA) was 87.5° (range,84°-90°) which was 76.1° (range,66°-82°) before operation.The mean medial proximal tibia angle (MPTA) was 87.8° (range,86°-89°) which was 76.8° (range,68°-80°) before operation.There were no deep infection and neurovascular injury.Conclusion The FAIF not only has the advantage of minimal invasiveness and easy adjustment,but also can avoid uncomfortableness and complications of long-term of wearing the external fixator.It is an accurate and safe method to correct the deformities around the knee joint.