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Objective:To investigate the therapeutic effect of open suture and selective suture in patients with high complexity anal fistula and its effect on anal function and complications.Methods:Prospectively selected 174 patients with high complex anal fistula who were hospitalized in the Anorectal Surgery Department of the Second People′s Hospital of Yibin City from December 2018 to December 2021 as the study subjects, including 138 males and 36 females, aged from 26 to 45 years, with an average of (35.20 ± 8.86) years. According to the admission order of patients, grouped them into single and double numbers, with single numbers being the control group ( n=87) and double numbers being the observation group ( n=87). The control group was treated with traditional incision and thread hanging therapy, while the observation group was treated with selective suture through incision and thread hanging therapy. Compared the surgical time, blood loss, surgical cost, wound healing time, and anal function at 6 months after surgery between the two groups of patients. Compared the treatment effects of two groups of patients at 6 months after surgery. Compared the postoperative complications within 6 months and recurrence within 1 year between the two groups. The measurement data subject to normal distribution were expressed by mean ± standard deviation( ± s). The two groups were compared by independent sample t test, and the count data were compared by Chi-square test. Rank sum test was used for comparison of hierarchical data. Results:The surgical time in the observation group was higher than that in the control group [(44.30 ± 8.11) min vs (42.18 ± 7.25) min, ( t=-2.44, P<0.05], and the surgical cost was higher than that in the control group [(1184.81 ± 372.68) yuan vs (835.28 ± 320.03) yuan, t=-8.75, P<0.001]. There was no statistically significant difference in blood loss data between the two groups [(19.57 ± 6.07) mL vs (18.35 ± 5.25) mL, t=-1.88, P>0.05]. The length of wound healing time in the observation group was lower than that in the control group [(24.18 ± 4.35) d vs (29.35 ± 5.08) d, t=11.09, P<0.001]. The anal function score of the observation group at 6 months after surgery was lower than that of the control group [(4.80 ± 1.21) score vs (6.71 ± 1.35) score, t=14.72, P<0.001]. All patients did not experience any loss of follow-up. In the comparison of treatment effects 6 months after surgery, the observation group had a better efficacy rating than control group ( Z=3.86, P<0.001). At 6 months after surgery, the incidence of complications in the observation group was lower than that in the control group [2.30% (2/87) vs 10.34% (9/87), χ2=4.76, P<0.05]. One year after surgery, the recurrence rate in the observation group was lower than that in the control group [2.30% (2/87) vs 10.34% (9/87), χ2=4.76, P<0.05]. Conclusion:The application of incision and thread-drawing selective suture in the treatment of patients with high complex anal fistula is beneficial to the treatment effect of patients, reduces postoperative complications, and protects the anal function of patients, with good use value.
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Liver cancer is one of the most common cancers in China. In recent years, liver cancer tends to be treated with comprehensive therapies, including surgery, ablation, interventional embolization, radiotherapy, chemotherapy, targeted therapy, immunotherapy, and liver transplantation. At present, the low surgical resectionrate is one of the main factors affecting the prognosis of liver cancer patients. Preoperative neoadjuvant therapy or conversion therapy for liver cancer can maximize the rate of surgical resection and improve the prognosis. With the rapid development of radiotherapy and immunotherapy in the comprehensive treatment of liver cancer, it has been gradually confirmed that the unique effects of preoperative radiotherapy and immune therapy for liver cancer can improve the prognosis of the patients. Therefore, this paper reviewed the research progress in the preoperative radiotherapy and immunotherapy for liver cancer by searching relevant literature and reports at home and abroad.
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Objective To evaluate the geometric and dosimetric accuracy of autosegmentation software for contouring the organ-at-risk ( OAR) of esophageal cancer, and discuss its clinical feasibility. Methods A total of 10 patients were enrolled, and single and multi-template were adopted respectively to auto-delineate corresponding OARs on target CT images based on image registration. The geometric consistency including volume difference (ΔV) , dice similarity ( DSC) and position difference (Δx, Δy,Δz) between the two autosegmentation method and manual were compared using Wilcoxon signed-rank test. And the correlation between DSC and OAR volume was analyzed. In addition, to evaluate the clinical feasibility of autosegmentation, the dose distributions of all OARs were compared using Friedman test. Results The average DSC of all OARs obtained by single and multi-template were 0.82 ± 0.17 and 0.92 ± 0.54, respectively, with statistically significant difference (Z= -2.803- -2.497, P<0.05). A positive correlation between DSC of the autosegmentation and OAR volume was found by spearman analysis, and the single-template was not good enough for the spinal cord with smaller volume. The positional deviations of multi-template group were less than 0.5 cm in three directions, which were better than single-template group. The main dosimetric indexes of single-template and multiple-template were similar to manual coutours. V20 of whole lung were 23.2％, 22.4％ and 22.1％, Dmeanof whole lung were (11.3 ±4.0), (11.1 ±4.5) and (11.0 ±4.3) Gy, Dmaxof spinal cord were (40.3 ±4.8), (38.2 ±6.7) and (39.4 ± 5.3) Gy, respectively, and V30 of heart were 16.0％, 15.8％ and 15.5％, respectively. There was no statistical difference between the three methods (P>0.05), and all of the dosimetric indexes were in line with the requirements of clinical dose limits. Conclusions The autosegmentation software can achieve satisfactory precision for the OARs of the esophageal cancer patients, and the multi-template method is better than the single-template, which is more suitable for clinical application.
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Objective To compare the dosimetric difference among plans designed by 4-field,6-field TomoDirect and TomoHelical techniques in Tomotherapy system for left-breast cancer patients with radiotherapy after breast-conserving surgery.Method A total of 16 patients with left-breast cancer following breast-conserving surgery and intensity-modulated radiation therapy were enrolled in this retrospective study.The 4-field TomoDirect (TD4),6-field TomoDirect (TD6),and TomoHelical (TH) techniques were applied to design simulation plans in tomotherapy system for each patient,respectively.The differences of dose distribution and treatment parameters were analyzed in this study.Results Three plans all met the clinical requirement.Thereinto,TD4 was superior to TH in the dose limitation of organs at risk (OARs),especially the max dose of cord and right-breast,thc 5 Gy radiation volume of lung,and the mean dose of heart(F =595.60,129.24,60.44,65.37,P ＜ 0.05),but inferior to TH in dose homogeneity (HI) and conformity (CI) (F =2.78,60.93,P ＜ 0.05).However,TD6 improved TD4's HI and CI when delivered the lower OARs dose compared to TH.Meanwhile,the number of monitor units was less in TD technique and reduced the treatment times (F =24.89,3.75,P ＜ O.05).Conclusions For the radiotherapy of left-breast cancer patients after breast-conserving surgery,TD6 technique appeared to be superior,with the lower radiation dose of OARs compared to TH technique,and the better target's HI and CI in comparison with TD4 technique,especially in patients with early stage breast cancer.
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Objective To simulate the possible systematic delivery errors introduced by monitor units ( MU) and multi-leaf collimator ( MLC) in radiotherapy plans for nasopharyngeal carcinoma ( NPC) , and to analyze the dosimetric sensitivity of static intensity-modulated radiotherapy ( IMRT ) and volumetric modulated arc therapy ( VMAT) with these errors. Methods Five IMRT plans were replanned using VMAT modality with the same physical parameters, and then MU errors of 125%, 250%, and 5. 00% were introduced into IMRT and VMAT plans. Meanwhile, to simulate leaf position errors during delivery, MLC position errors (025 mm, 050 mm, 100 mm, 150 mm, and 200 mm) were introduced by modifying the original plan documents. The types of MLC errors were as follows:( 1) the MLC banks moved in the same direction;( 2) the MLC banks moved in opposing directions ( expand or contract the MLC gaps ) . The differences in dosimetric sensitivity introduced by MU and MLC errors between IMRT and VMAT plans for NPC were calculated by linear regression analysis. Results With the increase in MU errors, the doses to target and organs at risk ( OARs) of IMRT and VMAT plans increased in a linear way, and met R2=0992-1000( P<005) . For MLC errors, the average dosimetric sensitivity for target and OARs of IMRT and VMAT were-026%/mm and-065%/mm in case of offset errors, 487%/mm and 868%/mm in case of expansion errors, and -604%/mm and -988%/mm in case of indentation errors. In addition, the dosimetric sensitivity with the three types of MLC errors was greater for VMAT plan than for IMRT plan. ConclusionsMU and MLC errors have a significant effect on the dose distribution of IMRT, and particularly VMAT, for NPC. It is important to execute routine quality assurance of MLC to ensure accurate radiotherapy.
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Objective To simulate the possible systematic delivery errors introduced by monitor units ( MU) and multi-leaf collimator ( MLC) in radiotherapy plans for nasopharyngeal carcinoma ( NPC) , and to analyze the dosimetric sensitivity of static intensity-modulated radiotherapy ( IMRT ) and volumetric modulated arc therapy ( VMAT) with these errors. Methods Five IMRT plans were replanned using VMAT modality with the same physical parameters, and then MU errors of 125%, 250%, and 5. 00% were introduced into IMRT and VMAT plans. Meanwhile, to simulate leaf position errors during delivery, MLC position errors (025 mm, 050 mm, 100 mm, 150 mm, and 200 mm) were introduced by modifying the original plan documents. The types of MLC errors were as follows:( 1) the MLC banks moved in the same direction;( 2) the MLC banks moved in opposing directions ( expand or contract the MLC gaps ) . The differences in dosimetric sensitivity introduced by MU and MLC errors between IMRT and VMAT plans for NPC were calculated by linear regression analysis. Results With the increase in MU errors, the doses to target and organs at risk ( OARs) of IMRT and VMAT plans increased in a linear way, and met R2=0992-1000( P<005) . For MLC errors, the average dosimetric sensitivity for target and OARs of IMRT and VMAT were-026%/mm and-065%/mm in case of offset errors, 487%/mm and 868%/mm in case of expansion errors, and -604%/mm and -988%/mm in case of indentation errors. In addition, the dosimetric sensitivity with the three types of MLC errors was greater for VMAT plan than for IMRT plan. ConclusionsMU and MLC errors have a significant effect on the dose distribution of IMRT, and particularly VMAT, for NPC. It is important to execute routine quality assurance of MLC to ensure accurate radiotherapy.
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Objective To test and evaluate the geometric accuracy of delineation of organs at risk ( OARs) in head and neck cancer using an atlas?based autosegmentation ( ABAS) software. Methods The atlases for the ABAS software was generated using images from 40 patients with head and neck cancer undergoing intensity?modulated radiotherapy. The software was tested in 40 new patients. Automatic delineation of OARs was carried out on computed tomography images by single?( one to one ) and multi?template ( ten to one) approaches. In order to evaluate the feasibility of the automatic delineation in clinical application, differences in volume (ΔV%), position (Δx,Δy, andΔz), conformability (sensitivity ( Se ), specificity ( Sp ) , and dice similarity coefficient ( DSC) ) , and delineation time were assessed between the automatic and manual delineation. The comparison between the two automatic delineation approaches was made by paried t test. Results For all OARs, the multi?template automatic delineation achieved a significantly smaller mean ΔV% value and a significantly larger mean DSC value than the single?template automatic delineation (-0.02%± 0?29% vs. -0.16%± 0?41%, P<0?05;0.74± 0?16 vs. 0.68± 0?20, P<0?05);the position differences between two automatic delineation approaches were less than 0?4 cm in all three directions except for the temporal lobe, lower jaw, and spinal cord;in the receiver operating characteristic curve defined by Se versus 1-Sp , the data points were all within the first quadrant except for the optic nerve and chiasm;automatic delineation saved 42%?72% of time compared with manual delineation. Conclusions The ABAS software achieves satisfactory results of automatic delineation for most of OARs in patients with head and neck cancer. The multi?template automatic delineation, particularly, has better outcomes than the single?template one. In addition, it greatly shortens the time the clinicians spend on delineation of OARs.
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Background and purpose:Currently, subjective questionaire is the most frequently used methods to evaluate swallowing dysfunctions after radiotherapy in nasopharyngeal carcinoma patients, while lacking of effective objective examinations. This study aimed to explore effective methods to evaluate swallowing dysfunctions after radiotherapy in nasopharyngeal carcinoma patients, and gain knowledge of the incidence and severity of swallowing dysfunctions. Methods: From Oct. 2013 to Dec. 2013, 128 consecutive outpatients with previously treated nasopharyngeal carcinoma received esophageal barium lfuoroscopy examination at there regularly follow-ups to evaluate swallowing function. Among these patients, 89 were primary treated with intensity modulated radiation therapy (IMRT) and 39 with conventional radiotherapy (CRT). In this study, each patient received esophageal barium lfuoroscopy examination for 3 times with thin, thick and pasty barium and were dynamically observed using X-ray fluoroscopy from front and lateral direction. Swallowing dysfunctions were defined as follows:①The bolus could not be swallowed and blocked in the mouth;②The dilute barium diverted to the glottis or trachea;③Residual barium delayed in the pyriform sinus and vallecula;④The movement of the hyoid bone or epiglottis were restricted;⑤Bolus prolong through the pharynx;⑥Barium slowed down when went though the esophageal entrance. Results:Of the 128 patients, incidence of dysphagia was 60.2%for the entire cohort, 52.8%for IMRT group and 76.9%for CRT group. Incidence of dysphagia for IMRT group was signiifcantly lower than CRT group (P=0.018). Dysphagia incidence within 1 year, 1 to 2 years and more than 2 years after RT were 63.1%, 33.3%and 69.0%, respectively (P=0.019). Conclusion:There was a high incidence of swallowing dysfunction for the nasopharyngeal carcinoma patients treated with radiotherapy and dysphagia incidence decreased when treated with IMRT. Esophageal barium lfuoroscopy examination is objective method to evaluate the incidence and severity of the swallowing dysfunction.
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Objective To compare the static intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) for mid and upper thoracic esophageal cancer.Method The data of twenty esophageal cancer patients were retrospectively re-planned with VMAT(single arc and double arcs) modality using Pinnacle treatment plan system.Five of these patients were selected again to simulate single arc plans with different segment intervals (4°,3°,2°) and re-planned on other treatment planning systems (Monaco and MasterPlan).Differences of dose distribution and treatment parameters were compared.Results In comparison to IMRT and single-VMAT (S-VMAT),Double-VMAT (D-VMAT) significantly improves the dosimetric parameters for targets(P ＜ 0.05),dose homogeneity(P ＜ 0.05) and conformity(P ＜ 0.05).Though VMAT plans were slightly better than IMRT in reducing the doses to the organs at risk (OARs),no advantage was observed in the low-dose protection of lung and E-P (P ＜ 0.05).For the VMAT plans with different segment intervals,lower OAR doses were observed using an interval of 2°(P ＜ 0.05),except for the mean dose of the heart.For the VMAT plans on different treatment planning systems,Monaco-based plans protected OARs better (P ＜ 0.05).The number of monitor units (MU) and treatment time were less in VMAT cases.Conclusions VMAT plans perform better in target coverage,dose homogeneity and conformity,and can reduce the radiation dose to the spinal cord,lungs,heart and other normal tissue than IMRT plans.The VMAT plan quality could be further improved by using double arcs and smaller segment interval.Monaco-based plans provide better OAR protections under the same conditions of physical and optimization parameters.
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Objective To investigate and analyze the positioning accuracy of three imaging modalities utilized in image-guided radiotherapy (IGRT):electronic portal imaging device ( EPID),kV portal image (kV planar) and the kV cone beam computed tomography (CBCT).Methods 25 groups of setup errors were simulated on the phantom images through treatment planning system. Digitally reconstructed radiographs (DRRs) were constructed from the CT data which were subsequently used as references to register the EPID and kV planar images acquired at the original position.In addition,the reconstructed 3D-CT images were used to register the CBCT images.Finally,the setup errors using several registration methods were measured to investigate and compare the accuracies of the three imaging modalities used for patient setup.Results 675 groups of residual errors were analyzed.All combinations of imaging modalities and registration method were found to be accurate.The mean residual errors in three directions were less than 1 mm.The method based on grey value match of CBCT images was found as the most accurate with an uncertainty below 0.1 mm.When the manual match was used,the performance of kV planar was more accurate than that of EPID (residual error ＜ 0.65 mm).If automatic registration was applied,kV planar generated similar results as EPID did. Conclusions The three available imaging modalities and their corresponding registration methods are all competent for the clinical application of IGRT in our department.Considering the image quality,radiation dose and the accuracy of registration,CBCT has the priority on 1GRT followed by the kV planar.
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Objective To evaluate the autocontouring accuracy using the atlas-based autosegmentation of CT images for head-and-neck cancer.Methods Ten head and neck patients with contours were selected.Two groups of autocontouring atlas were tested,the first group was for patients with own atlas,for the second group we tested the autocontouring of eight patients with other two patients atlas.Dice similarity coefficient (DSC) and overlap index (OI) were introduced to evaluate the autocontours,and the discrepancy between the two groups was evaluated through paired t-test.Results Both the DSC and OIof all the organs in the first group were ＞0.80,the result of mandible was the highest ( ＞0.91 ),the DSC of the gross tumor volume (GTV) was the lowest (0.81 ),the OI of the GTV was 0.82,and the DSC and OI of the clinical target volume (node) were 0.82 and 0,79,respectively.Only the risk organ was delineated in the second group,and spinal cord and brain stem were combined to analyze.All the DSC was about 0.70,and the DSC and OI of mandible were higher than the others,which was due to its bone anatomy.The accuracy in the second group was significantly lower than that of the first group ( t =3.24 - 8.26,P =0.014 -0.000),except the right parotid (t=2.08,P=0.075).Conclusions Automatic segmentation generates contours of sufficient accuracy for adaptive planning intensity-modulated radiotherapy (IMRT) to accommodate anatomic changes during treatment.For convention planning IMRT normal structure auto-contouring,it need to select more standard atlas in order to acquire a satisfied autocontours.
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Objective To scrutinize the positioning accuracy and reproducibility of the cone-beam computed tomography system in combination with the six-degree couch table (Hexapod Robot Treatment Table, HRTT). Methods The mechanical stability of the X-ray volume imaging (XVI) system was tested,in terms of the reproducibility. And the influence of the moveable parts, including the KV panel and the source arm, on the accuracy of the XVI image registration was analyzed. The accuracy between the bone and grey value registration was compared using a head-and-neck phantom. The accuracy of the HRTT for translational, rotational, and a combination of translational and rotational corrections was investigated in consecutive measurements. Results The performance of XVI system itself was stable with translational and rotational error of below 0. 4 mm and below 0. 3°, respectively. The mean position accuracy of the XVI system in combination with the HRTT summarized over all measurements was below 0. 6 mm and below 0. 4° for translational and rotational corrections, respectively. The grey value match was more accurate than the bone match. Conclusions The XVI image acquisition and registration procedure were highly reproducible.Both translational and rotational positioning errors can be corrected very precisely with the HRTT. The HRTT is therefore well suited to complement CBCT to take full advantage of position correction in six degrees of freedom for image guided radiotherapy.
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Objective To explore six-degree-of-freedom (6-DF) registration methods between planning and cone beam computed tomography (CBCT) during image-guided radiation therapy (IGRT) in esophageal cancer.Methods Thirty pairs of CBCT images acquired before radiation and the corresponding planning computed tomography (CT) images of esophageal cancer were selected for further investigation.Registration markers for 6-DF image registration were determined and contoured in those images.The results of registration as well as time cost were compared among different registration methods of bone match, gray value match, manual match, and bone plus manual match.Results Contouring bone and spinal canal posterior to the target volume of esophageal carcinoma as registration marker could make 6-DF registration quick and precise.Compared with manual match, set-up errors of v rotation in bone plus manual match (-0.55° vs.-0.88°, t=2.55, P=0.020), of x-axis and v rotation in bone match (0.12 mm vs.-2.33 mm, t=5.75, P=0.000; -0.35° vs.-0.88°, t=3.00, P=0.007), and of x-axis and w rotation in gray value match (7.20 mm vs.-2.33 mm, t=3.10, P=0.006; -0.10° vs.-0.59°, t=2.81, P =0.011) were significantly different.Compared with manual match, the coincidence rate of bone plus manual match was the highest (85.55%), followed by bone match and gray value match (74.45% and 74.45%).The time cost of each registration method from longest to shortest was:6.00 -10.00 minutes for manual match, 1.00 - 5.00 minutes for bone plus manual match, 0.75 - 1.50 minutes for gray value match, and 0.50 - 0.83 minutes for bone match.Conclusions Registration marker is useful for image registration of CBCT and planning CT in patients with esophageal cancer.Bone plus manual match may be the best registration method considering both registration time and accuracy.