Research progress on the application of four-dimensional CT combined with four-dimensional cone beam CT in stereotactic radiotherapy for lung cancer / 中国医学装备

High-precision radiotherapy represented by stereotactic body radiation therapy(SBRT)plays an important role in every stage of lung cancer treatment.The development of medical imaging technology,more accurate dose calculation methods,and the application of advanced imaging and dose verification algorithms provide guarantee for the realization of high-precision radiotherapy.Four-dimensional computed tomography(4D CT)can better display the individualized motion of tumors affected by respiration.Four-dimensional cone beam computed tomography(4D-CBCT)is an image-guided technology to delineate and obtain the internal target volume(ITV),which Can provide guarantee for precise treatment.The combination of the two technologies can correct the displacement error,monitor the range of tumor motion,and ensure that the moving target is within the irradiation range,which is the guarantee of stereotactic radiotherapy.From the perspective of image-guided radiation technology in the application of precise radiotherapy for lung cancer,the clinical application value of 4D CT combined with 4D-CBCT in SBRT of tumors was reviewed,aiming to provide reference for clinical radiotherapy of lung cancer.

A study of the performance evaluation of iCBCT imaging mode / 中华放射肿瘤学杂志

Objective:To comprehensively evaluate the performance of the iterative cone beam CT (iCBCT) imaging mode of Varian linear accelerators and to explore its specific advantages in clinical application.Methods:The kV cone beam CT (CBCT) imaging systems of Halcyon 2.0, Edge, and VitalBeam linear accelerators from Tianjin Medical University Cancer Institute & Hospital were selected, among which Halcyon 2.0 and Edge were equipped with the iCBCT imaging mode. The Penta-Guide phantom was used to evaluate the registration accuracy of iCBCT imaging modes. The accuracy of treatment couch position was measured by a ruler. The image quality of the iCBCT and conventional CBCT modes of various imaging devices were analyzed using the CatPhan604 phantom. The imaging beam-on time and reconstruction time were measured to assess image acquisition efficiency. The uniformity, spatial resolution, contrast, contrast-to-noise ratio (CNR), image acquisition time and reconstruction time between two imaging modes were statistically analyzed by t-test. Results:The maximum deviations of image registration measurement results of the iCBCT mode for Halcyon 2.0 and Edge accelerators compared to the standard values were 0.7 mm and 0.6 mm, respectively. The treatment couch position error of all devices was less than 1 mm. The iCBCT images under head scanning protocol primarily improved the uniformity and CNR. Compared to conventional CBCT images, Halcyon iCBCT increased the uniformity and CNR by 2.50% ( P<0.001) and 78.85% ( P<0.001), respectively, while Edge increased them by 2.18% ( P<0.001) and 86.42% ( P<0.001), both superior to VitalBeam CBCT images. Under pelvis scanning protocols, iCBCT images primarily improved the CNR compared to conventional CBCT images. Halcyon and Edge iCBCT increased the CNR by 113.57% ( P<0.001) and 133.87% ( P<0.001), respectively, both superior to VitalBeam CBCT images. In terms of image acquisition efficiency, the average reconstruction times for Halcyon and Edge iCBCT images increased by 7.28 s and 15.53 s, respectively, and the total image acquisition time of Halcyon accelerator was the shortest. Conclusions:While ensuring the registration accuracy, iCBCT imaging mode can significantly improve the CNR of images and improve the uniformity of images under head scanning protocol. The Halcyon imaging system can enhance image acquisition efficiency.

Application value of optical surface monitoring system volume rendering technique body surface imaging in intensity-modulated radiotherapy for thoracic tumors / 肿瘤研究与临床

Objective:To explore the application value of optical surface monitoring system (OSMS) volume rendering technique (VRT) body surface imaging in intensity-modulated radiotherapy for thoracic tumors.Methods:A retrospective case series study was performed. The clinical data of 65 patients with thoracic tumors treated with intensity-modulated radiotherapy at Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology from September 2021 to October 2022 were retrospectively analyzed. In the first treatment,after cone-beam computed tomography (CBCT) scan and correction, VRT body surface images were obtained by using OSMS. In subsequent treatment, the VRT image was used as the benchmark and the 6-dimensional bed was automatically positioned to record the 6-dimensional bed positioning value. The CBCT scan was performed to record the translation and rotation errors of left-right direction (X-axis), head-foot direction (Y-axis) and front-rear direction (Z-axis). After the calibration of the 6-dimensional automatic bed shifting, the new real-time deltas (RTD) value of digital imaging and communications in medicine (DICOM) body surface image was recorded, and the new VRT image was obtained. CBCT registration error value was defined as VRT image-guided setup error. The sum of CBCT registration error value and moving bed movement value was defined as the body surface marker line-guided setup error. The sum of CBCT registration error value and the recorded DICOM image RTD value was defined as the theoretical error of DICOM image-guided setup. The advantages and disadvantages of VRT image, body surface marker line and DICOM image-guided setup were compared and analyzed.Results:There were 42 males and 23 females in 65 patients with thoracic tumors, and the age [ M ( Q1, Q3)] was 58 years (51 years, 64 years). The linear errors [ M ( Q1, Q3)] of VRT image-guided setup in X, Y and Z axes were 0.6 mm (0.3 mm, 1.2 mm), 1.2 mm (0.5 mm, 2.4 mm) and 1.1 mm (0.5 mm, 1.9 mm); and the rotational errors were 0.4° (0.1°, 0.7°), 0.4° (0.1°, 0.6°) and 0.4° (0.2°, 0.6°). The linear errors of the marker line-guided setup were 1.6 mm (0.9 mm, 2.6 mm), 2.2 mm (1.1 mm, 3.8 mm) and 1.0 mm (0.4 mm, 1.8 mm); and the rotational errors were 0.7° (0.3°, 1.2°), 0.5° (0.2°, 0.8°) and 0.5° (0.2°, 0.8°). The linear errors of the DICOM image-guided positioning were 1.1 mm (0.6 mm, 1.9 mm), 2.1 mm (1.0 mm, 3.4 mm) and 1.3 mm (0.6 mm, 3.1 mm), and the rotational errors were 0.6° (0.2°, 1.1°), 0.7° (0.3°, 1.1°), 0.7° (0.2°, 1.1°). Compared with the marker line-guided setup, except for Z-axis linear error ( P = 0.218), the VRT-guided setup errors were low (all P < 0.001). Compared with the DICOM imaging-guided setup, the VRT image-guided setup linear error and rotational error in X-, Y- and Z-axis were low (all P < 0.01). Conclusions:VRT image-guided setup is superior to traditional body surface marker setup and DICOM imaging setup; OSMS VRT body surface imaging can effectively improve the setup accuracy and stability of intensity-modulated radiotherapy for thoracic tumors, and reduce the setup errors.

Clinical application of MR-guided radiotherapy based on MR-linac in esophageal cancer patients / 国际肿瘤学杂志

Objective:To explore the application process, efficacy and safety of MR-guided radiotherapy based on MR-linac in esophageal cancer.Methods:The clinical data of patients with esophageal cancer treated with MR-linac at Shandong Cancer Hospital and Institute from September 2021 to July 2022 were retrospectively analyzed, to investigate the treatment process of esophageal cancer with MR-linac, and to analyze the efficacy and safety of patients. All patients received MR-guided radiotherapy, underwent CT and MR localization, target area delineation, and design of the Monaco treatment planning system plan. Adaptation-to-position adjustment was conducted during the pre-treatment evaluation. The median number of fractions was 25, the median single dose of planning target volume was 1.8 Gy, and the median total dose was 50.2 Gy. Median follow-up was 16 months.Results:Among the 12 patients in the whole group, there were 1 case of cervical esophageal cancer, 3 cases of upper thoracic esophageal cancer, 4 cases of middle thoracic esophageal cancer and 4 cases of lower thoracic esophageal cancer, including 3 cases of neoadjuvant radiotherapy and 9 cases of radical radiotherapy. All patients had a smooth treatment process. The median treatment time was 33 min, and the patients had good compliance. For patients with radical radiotherapy, one month after radiotherapy, the number of objective remission cases was 3, and the number of disease-control cases was 9; six months after radiotherapy, the number of objective remission cases was 3, and the number of disease-control cases was 6. All patients treated with neoadjuvant radiotherapy underwent surgery within 2 months, and one patient achieved pathological complete remission. The most common acute adverse reactions were radiation esophagitis (7 cases) and leukopenia in bone marrow suppression (8 cases), with late-stage adverse reactions being radiation pneumonia (1 case). The adverse reactions to radiotherapy were slight, and no grade 4 or above adverse reactions were observed.Conclusion:The clinical treatment process for esophageal cancer under MR-guided radiotherapy based on MR-linac is feasible, with good curative effects and mild adverse reactions.

Application and evaluation study of 3D ultrasound in image guided radiotherapy for prostate cancer / 国际肿瘤学杂志

Objective:To evaluate the accuracy of 3D ultrasound calibration in image guided radiotherapy for prostate cancer by taking cone beam CT calibration as the gold standard, and to analyze the risk factors of accuracy.Methods:From December 2018 to December 2021, 51 patients with prostate cancer from the Department of Radiation Oncology, First Affiliated Hospital of Hebei North University were selected as the study subjects. They received cone beam CT calibration based on bone and 3D ultrasound calibration based on soft tissue before fraction volumetric modulated arc therapy treatment three times a week. Taking cone beam CT calibration data as the gold standard, the Bland-Altman method was used to analyze the consistency of 3D ultrasound calibration data with the former. Taking 3 mm as the allowable threshold of accuracy, the calibration accuracy of 3D ultrasound relative to cone beam CT was evaluated. Logistic regression was used to analyze the risk factors affecting the accuracy of 3D ultrasound calibration.Results:A total of 765 pairs of cone beam CT and 3D ultrasound calibration data were obtained from 51 patients in left-right, superior-inferior and anterior-posterior directions. The calibration data of 3D ultrasound and cone beam CT were (1.39±0.11) and (1.13±0.07) mm in the left-right direction, (1.98±0.20) and (1.61±0.12) mm in the superior-inferior direction, (2.68±0.48) and (1.78±0.27) mm in the anterior-posterior direction, respectively, with statistically significant differences ( t=-6.42, P<0.001; t=-7.07, P<0.001; t=-7.34, P<0.001). The analysis results of Bland-Altman showed that the consistency of calibration data of the two methods were acceptable in three directions. The number of pairs of 3D ultrasound relative to cone beam CT calibration data difference <3 mm in the three directions were 676 (88.37%) on the left-right direction, 604 (78.95%) on the superior-inferior direction, and 577 (75.42%) on the anterior-posterior direction. The factors with statistically significant differences in the left-right direction included age ( χ2=18.27, P<0.001), prostate volume ( χ2=14.55, P<0.001), Charlson comorbidity index (CCI) ( χ2=8.01, P=0.005) and field range ( χ2=11.30, P<0.001). Age ( OR=2.02, 95% CI: 1.90-3.39, P=0.010) and the field range ( OR=1.45, 95% CI: 1.18-2.55, P=0.020) were the independent risk factors affecting the accuracy of 3D ultrasound calibration in the left-right direction. The factors with statistically significant differences in the superior-inferior direction included age ( χ2=80.68, P<0.001), body mass index ( χ2=35.89, P<0.001) and field range ( χ2=40.39, P<0.001). Age ( OR=1.49, 95% CI: 1.15-2.09, P=0.021) and the field range ( OR=1.10, 95% CI: 1.01-1.90, P=0.034) were the independent risk factors affecting the accuracy of 3D ultrasound calibration in the superior-inferior direction. The factors with statistically significant differences in the anterior-posterior direction included age ( χ2=46.07, P<0.001), CCI ( χ2=47.97, P<0.001) and field range ( χ2=11.86, P=0.001). Age ( OR=1.91, 95% CI: 1.22-3.45, P=0.015) and the field range ( OR=2.89, 95% CI: 1.45-3.90, P=0.001) were the independent risk factors affecting the accuracy of 3D ultrasound calibration in the anterior-posterior direction. Conclusion:The consistency and accuracy of the calibration results of 3D ultrasound relative to cone beam CT are acceptable. It is necessary to consider the patient's age and field range to reduce the impact on accuracy before conducting 3D ultrasound calibration.

Application value of hydrogel in image guided radiotherapy for prostate cancer / 解放军医学杂志

Objective To evaluate the application value of hydrogel in image guided radiotherapy(IGRT)for prostate cancer(PCa).Methods Eighty PCa patients in the First Affiliated Hospital of Hebei North University from October 2022 to February 2023 were collected.The patients were divided into experiment group injected with hydrogel(n=33)and control group without hydrogel(n=47)by central random system allocation.The acute and advanced radiation proctitis(RP)incidence rate of the two groups were compared.Patients in experimental group were divided into RP group(n=5)and non-RP group(n=28).The independent risk factors leading to RP were analyzed by using logistic regression for PCa patients.Results In experiment group,12.1％(4/33)of the patients developed acute grade Ⅰ RP,and 3.0％(1/33)developed advanced grade Ⅰ RP.In control group,31.9％(15/47)of the patients developed acute grade Ⅰ RP,and 12.8％(6/47)developed acute grade Ⅱ RP;19.1％(9/47)of patients developed advanced grade Ⅰ RP,4.3％(2/47)developed advanced grade Ⅱ RP,and 2.1％(1/47)developed advanced grade Ⅲ RP.The incidence of acute and advanced RP in experiment group was lower than that in control group(P<0.05).The application of hydrogel effectively reduced rectal toxicity.Age,rectal volume,V70 and V78 were independent risk factors for the incidence of RP in Pca patients(P<0.05).The characteristics of hydrogel injection were not related to the incidence of RP for Pca patients.Conclusions Hydrogel can effectively reduce the rectal toxicity for Pca patients in IGRT and has little impact on the overall treatment.Hydrogel has certain clinical application and promotion value.

Vacuum-assisted excision of breast lesions in surgical de-escalation: where are we? / Excisão assistida a vácuo de lesões mamárias no descalonamento cirúrgico: onde estamos?

Abstract Vacuum-assisted excision of breast lesions has come to be widely used in clinical practice. Increased acceptance and availability of the procedure, together with the use of larger needles, has allowed the removal of a greater amount of sample, substantially reducing the surgical upgrade rate and thus increasing the reliability of the results of the procedure. These characteristics result in the potential for surgical de-escalation in selected cases and gain strength in a scenario in which the aim is to reduce costs, as well as the rates of underestimation and overtreatment, without compromising the quality of patient care. The objective of this article is to review the technical parameters and current clinical indications for performing vacuum-assisted excision of breast lesions.

Resumo A excisão assistida a vácuo de lesões mamárias tem sido cada vez mais utilizada na prática clínica. A sua maior aceitação e disponibilidade, em associação ao uso de agulhas mais calibrosas, permitiu a retirada de quantidade maior de amostra, reduzindo substancialmente a taxa de subestimação diagnóstica e aumentando, assim, a confiabilidade final dos resultados do procedimento. Essas características resultam em potencial descalonamento cirúrgico, em casos selecionados, e ganham força em um cenário em que se visa a redução de custos, taxa de subestimação e tratamento excessivo, porém, sem comprometer a qualidade no cuidado com o paciente. O objetivo deste trabalho é revisar os parâmetros técnicos e as indicações clínicas atuais para realização de excisão assistida a vácuo em lesões mamárias.

Analysis of Imaging Performance Standards of CBCT X-IGRT System Used in Radiotherapy / 中国医疗器械杂志

This article briefly describes the imaging performance standards of the kilovolt X-ray image guidance system used in radiotherapy, analyzes the main aspects that should be considered in the image quality of X-IGRT system, and focuses on parameters that should be considered in the imaging performance evaluation criteria of the CBCT X-IGRT. The purpose is to sort out the imaging performance evaluation standards of kilovolt X-IGRT system, clarify the image quality requirements of X-IGRT equipment, and reach a consensus when evaluating the imaging performance of X-IGRT system.

Image-guided Strategy of Intensity-modulated Radiotherapy in Helical Tomography for Nasopharyngeal Carcinoma / 中山大学学报(医学科学版)

ObjectiveThis study aimed to analyze the difference in setup error before and after correction of systematic error. To determine the most appropriate image-guided strategy during HT treatment， we use different scanning ranges and image-guidance frequencies in patients with nasopharyngeal carcinoma （NPC） treated with helical tomotherapy （HT）. MethodsFifteen patients with NPC who received HT treatment in Sun Yat-sen University Cancer Center from October 2019 to February 2020 were selected. Megavoltage computed tomography （MVCT） scanning was performed before each treatment. After five times of radiotherapy， system-error correction was performed to adjust the setup center. The setup errors before and after the correction of systematic errors， as well as the setup errors of different scanning ranges and different scanning frequencies， were collected for analysis and comparison. ResultsWhen comparing the setup errors before and after the correction of systematic error， the differences in setup errors in the left–right （LR）， superior–inferior （SI）， and anterior–posterior （AP） directions were statistically significant （P<0.05）.The different scanning ranges of "nasopharynx + neck" and "nasopharynx" were compared， and a statistically significant difference was found in yaw rotational errors （P<0.05）. In the comparison of daily and weekly scan frequency after system-error correction， a significant difference was found in AP direction （P<0.05）. ConclusionDuring radiotherapy for NPC， the systematic error can be corrected according to the first five setup errors， and then small-scale scanning was selected for image-guided radiotherapy every day.

Six novel minimally invasive therapies for benign prostatic hyperplasia / 浙江大学学报·医学版

Benign prostatic hyperplasia (BPH) is the most common cause of lower urinary tract symptoms in men. When drug treatment is ineffective or conventional surgery is not suitable, novel minimally invasive therapies can be considered. These include prostatic urethral lift, prostatic artery embolisation, water vapor thermal therapy, Aquablation-image guided robotic waterjet ablation, temporary implantable nitinol device and prostatic stents. These novel therapies can be performed in outpatient setting under local anesthesia, with shorter operative and recovery times, and better protection of ejaculatory function and erectile function. General conditions of the patient and advantages and disadvantages of the each of these therapies should be fully considered to make individualized plans.

Diagnostic value and safety of percutaneous renal biopsy at different puncture sites guided by real-time abdominal mode ultrasound with an L9 superficial probe / 中国基层医药

Objective:To investigate the best operation mode for percutaneous renal biopsy guided by real-time abdominal mode ultrasound, to increase the puncture success rate, and avoid serious complications using safe and effective renal puncture biopsy.Methods:A total of 44 patients with renal disease who received treatment in Ji'an Central People's Hospital from November 2019 to March 2022 were included in this study. According to the puncture location on the right kidney, these patients were divided into a control group (lower pole of the right kidney, n = 22) and an observation group (middle and lower pole of the right kidney, n = 22). A percutaneous renal biopsy was performed from the back to the right side of the spine under the guidance of abdominal mode ultrasound with an L9 superficial probe. General data, the number of punctures, the length of the safe puncture path, the maximum length of the tissue strip subjected to biopsy, the proportion of endothelial medulla in the tissue strip, the number of glomeruli, and the incidence of complications of perirenal hematoma were compared between the two groups. Results:All 44 patients succeeded in sampling, with a 100% success rate. A total of 7-32 glomeruli were obtained. A pathological diagnosis was made in all 44 patients. There were no significant differences in age, body mass, or medical history between the two groups (all P > 0.05). There were significant differences in the maximum length of renal tissue strip subjected to biopsy [(15.55 ± 1.75) mm vs. (11.45 ± 2.46) mm] and the number of glomeruli in renal tissue strip subjected to biopsy [(18.00 ± 6.12) vs. (11.32 ± 2.38)] between the two groups ( t = 6.20, 4.66, both P < 0.05). The difference in the incidence of complications of perirenal hematoma after percutaneous renal biopsy differed greatly between the two groups [100.0% (22/22) vs. 27.2% (6/22), χ2 = 3.86, P = 0.001]. No serious complications occurred in each group. There were no significant differences in the length of the safe puncture path, the number of punctures, or the proportion of endothelial medulla in tissue strips subjected to biopsy between the two groups (all P > 0.05). Conclusion:L9 superficial probe abdominal mode real-time ultrasound-guided percutaneous renal biopsy from the inside out has a good application value, a high puncture success rate, is safe and reliable, and yields a satisfactory pathological diagnosis. Percutaneous renal puncture biopsy of the middle and lower poles of the right kidney under the abdominal lobe has a higher pathological diagnostic value and is safer than percutaneous renal puncture biopsy of the lower pole of the right kidney.

Clinical effects of stereotactic-guided endoscopic hematoma removal combined with early systematic rehabilitation training on hypertensive intracerebral hemorrhage in the basal ganglia / 中国基层医药

Objective:To investigate the clinical effects of stereotactic-guided endoscopic hematoma removal combined with early systematic rehabilitation training on hypertensive intracerebral hemorrhage in the basal ganglia.Methods:A total of 130 patients with hypertensive intracerebral hemorrhage in the basal nucleus who received treatment in Zhejiang Veteran Hospital from June 2019 to December 2021 were included in this randomized control study. They were randomly divided into a control group and a study group ( n = 65 per group). The control group received minimally invasive hematoma puncture. The study group received stereotactic-guided neuroendoscopic hematoma removal. After surgery, early systematic rehabilitation training was carried out, and surgical indicators were recorded. The levels of serum inflammatory factors and stress factors were determined. The recurrence, death, and complications as well as prognosis of cerebral hemorrhage were recorded in each group. Results:The operative time in the study group was (85.39 ± 5.24) minutes, which was significantly longer than (64.17 ± 4.31) minutes in the control group ( t = -14.56, P < 0.001). Hematoma clearance rate in the study group was (94.66 ± 5.18) %, which was significantly higher than (76.82 ± 5.39) % in the control group ( t = -17.63, P < 0.001). At 24 hours after surgery, tumor necrosis factor-α, interleukin-1, norepinephrine, and hydrocortisone levels in the study group were (68.29 ± 5.36) ng/L, (237.62 ± 13.87) ng/L, (75.39 ± 5.82) μg/L, and (30.96 ± 2.97) μg/L, respectively, which were significantly lower than (74.61 ± 5.62) ng/L, (295.47 ± 14.69) ng/L, (91.62 ± 6.41) μg/L, and (38.25 ± 3.16) μg/L in the control group ( t = 7.95, 18.42, 16.84, 11.75, all P < 0.001). There was no significant difference in the 6-month mortality rate between the two groups ( P > 0.05). The recurrence rate of cerebral hemorrhage and the overall incidence of complications in the study group were (1.54% (1/65) and (10.77% (7/65) in the study group, respectively, which were significantly lower than 12.31% (8/65) and 27.69% (18/65) in the control group ( χ2 = 4.30, 5.99, both P < 0.05). The overall excellent and good prognosis rate within 6 months in the study group was 86.15% (56/65), which was significantly higher than 67.69% (44/65) in the control group ( χ2 = 6.24, P < 0.05). Conclusion:Compared with minimally invasive hematoma puncture and drainage surgery, stereotactic-guided neuroendoscopic hematoma removal takes longer time, but it can better effectively increase hematoma removal rate and alleviate stress and inflammatory reactions in patients with hypertensive intracerebral hemorrhage in the basal ganglia. Early systematic rehabilitation training combined with stereotactic guided neuroendoscopic hematoma removal can help reduce the risk of recurrence and complications of cerebral hemorrhage and improve prognosis.

Accuracy of the optically guided tracking system in radiotherapy / 中华放射医学与防护杂志

Objective:To explore the tracking accuracy of the surface optically guided tracking system (OGTS) in radiotherapy.Methods:Phantom verification and clinical trial verification were adopted. Specialized equipment was employed for the phantom verification. Specifically, the displacement of the optical markers as they moved from a predetermined position to the target position on the reflector ball platform was captured using the OGTS, and then the obtained displacement was compared with the fixed distance within the phantom to calculate the accuracy and repeatability of the OGTS. For the clinical trial verification, 45 patients treated with radiotherapy, which consisted of 15 cases with head, breast, and rectal tumors each, were selected to investigate the tracking accuracy and repeatability of the OGTS. For each patient, the values derived from the image-guided positioning system (IGPS) and the OGTS before and after image-guided setup error correction during three times of fractionated radiotherapy were randomly obtained. The translational errors of each error correction were also recorded. Before radiotherapy, patients′ setup errors were corrected and relevant data were obtained using the IGPS. The correction result of translation errors obtained using the IGPS served as a gold standard to verify the accuracy of the OGTS in monitoring the translational motion of patients. Finally, the comprehensive translational deviation of both method was calculated.Results:The phantom measurements showed that the comprehensive translational deviation for tracking accuracy and tracking repeatability of the OGTS had a maximum deviation and a standard deviation of 0.18 mm and 0.03 mm, respectively. The clinical trial result indicated that the tracking accuracy of IGPS and OGTS exhibited statistically significant differences only for the head in the z direction ( t = 2.21, P < 0.05). Conversely, no statistically significant differences were observed for the head in the remaining directions or for the breast and rectum in the three translational directions ( P > 0.05). The analysis showed that comprehensive translational deviations for the head, breast, and rectum derived from OGTS and IGPS were (0.91±0.62), (1.64±1.30), and (1.52±1.29) mm, respectively, satisfying the requirement that the deviations should be below 2 mm. Conclusions:The OGTS, featuring easy operation and high tracking accuracy, can assist the IGPS in real-time respiratory monitoring during radiotherapy.

Workflow and time efficiency analysis of different image guided brachytherapy for cervical cancer / 中华放射医学与防护杂志

Objective:To explore the radiation dose of brachytherapy plan for cervical cancer patients under different image-guided method and the time efficiency characteristics of each part of the clinical workflow, so as to provide reference for the overall arrangement of clinical brachytherapy.Methods:The workflow of 223 patients with brachytherapy was retrospectively analyzed. The whole workflow was divided into 5 parts: applicator placement, image acquisition, delineation of target and organs at risk, plan design and review, and treatment implementation. The image-guided brachytherapy was divided into X-ray guided 2D treatment groups, and computed tomography(CT)and magnetic resonance imaging (MRI) guided 3D treatment groups. The radiation dose and the time spent in each part of the three image-guided brachytherapy workflow were calculated. The radiation dose was evaluated using total reference air kerma (TRAK). The results were analyzed using the nonparametric test of SPSS 20 software.Results:TRAK 4.2(4.4, 3.9) cGy was significantly higher in X-ray guided 2D treatment group than in the CT guided 3D treatment group [3.5(3.9, 2.7) cGy, H =90.73, P < 0.01] and the MRI guided 3D treatment group[2.7(2.9, 2.4) cGy, H =90.73, P < 0.01]. The total workflow time of the X-Ray film guidance group was the shortest [55.0(67.0, 50.0) min], followed by the CT guidance group [80.0(91.0, 72.0) min], and the total workflow time of the MRI image guidance group was the longest [119.0(143.0, 105.5) min, H =106.39, P <0.01]. The image acquisition time of the MRI-guided group was significantly higher than that of the X-ray film guidance group and the CT-guided group ( H =44.80, P<0.01). The time of target delineation in the MRI-guided group was significantly longer than that in the CT-guided group ( Z=-5.10, P<0.01). The MRI-guided group took the longest time for planning, followed by the CT-guided group, and the X-ray guided group took the shortest time ( H =57.93, P<0.01). Conclusions:The 2D brachytherapy mode guided by X-ray film had the shortest process time but higher TRAK, while the 3D brachytherapy mode guided by MR had the longest process time, and the planned TRAK result were comparable to those guided by CT. When multiple patients are treated with brachytherapy at the same time, the work efficiency can be improved by interspersing different phases and the waiting time can be avoided.

Nursing of 1 case of intracranial air embolism after CT-guided percutaneous lung biopsy / 中国实用护理杂志

Objective:To report the first aid and nursing care of a case of intracranial air embolism after CT-guided percutaneous lung biopsy.Methods:The 1 case with intracranial air embolism after CT-guided percutaneous lung biopsy was given a series of treatment and nursing measures, including on-site first aid, hyperbaric oxygen therapy, sequential oxygen therapy and phased rehabilitation in Zhujiang Hospital, Southern Medical University in November 2022.Results:By giving timely and effective treatment and nursing measures, the patient recovered well and was discharged after 12 days of hospitalization.Conclusions:Intracranial air embolism is a critical disease, which should be mainly prevented, recognized, diagnosed and treated with hyperbaric oxygen as soon as possible.

Efficacy of radiofrequency ablation combined with ozone therapy under CT guidance in the treatment of lumbar disc herniation / 中国基层医药

Objective:To investigate the efficacy of radiofrequency ablation combined with ozone therapy under CT guidance in the treatment of lumbar disc herniation.Methods:A total of 93 patients with lumbar disc herniation who were admitted to The First Hospital of Jiaxing from January 2019 to May 2022 were included in this study. They were randomly divided into an observation group ( n = 47) and a control group ( n = 46). The control group was treated with radiofrequency ablation and the observation group was treated with radiofrequency ablation combined with ozone therapy. Efficacy was compared between the two groups at 3 months after surgery. The pain was compared between the two groups before and 7 days and 3 months after surgery. Inflammatory factors were compared between the two groups before and 7 days after surgery. The lumbar spine function was compared between the two groups before and 3 months after surgery. Results:At 3 months after surgery, the excellent and good rate in the observation group was significantly higher than that in the control group [89.36% (42/47) vs. 71.74% (33/47), χ2 = 4.63, P < 0.05). At 7 days and 3 months after surgery, Visual Analogue Scale scores in the observation group were (2.91 ± 0.54) points and (1.32 ± 0.31) points, respectively, which were significantly lower than (3.76 ± 0.62) points and (2.08 ± 0.47) points in the control group ( t = 7.06, 9.22, both P < 0.001). At 7 days after surgery, serum interleukin-1β, interleukin-6, and tumor necrosis factor-α in the observation group were (0.24 ± 0.05) μg/L, (18.49 ± 3.47) ng/L, and (97.94 ± 17.43) ng/L, respectively, which were significantly lower than (0.37 ± 0.09) μg/L, (24.31 ± 4.12) ng/L, and (148.87 ± 20.13) ng/L, respectively in the control group ( t = 8.63, 7.37, 13.05, all P < 0.05). At 3 months after surgery, the Japanese Orthopedic Association score in the observation group was significantly higher than that in the control group [(25.68 ± 2.28) points vs. (21.17 ± 3.24) points, t = -7.78, P < 0.001], and the Oswestry Disability Index in the observation group was significantly lower than that in the control group [(9.84 ± 1.43) points vs. (13.46 ± 2.18) points, t = 9.49, P < 0.001]. Conclusion:Radiofrequency ablation combined with ozone therapy under CT guidance is highly effective on lumbar disc herniation. The combined therapy can reduce pain and inflammatory reactions in patients and improve lumbar function.

Effects of tumor-treating field arrays on the radiation position and dose of glioblastoma / 中华放射医学与防护杂志

Objective:To preliminarily investigate the effects of tumor treating field (TTF) arrays on the positioning accuracy of radiotherapy setup in the treatment of glioblastoma.Methods:The kilovolt cone-beam CT (CBCT) and an X-ray volumetric imaging (XVI) system were used to verify the radiotherapy setup of 29 patients treated with conventional radiotherapy and 12 patients treated with TTF concurrent radiotherapy, respectively. The errors of radiotherapy position isocenter and treatment plan isocenter were evaluated in six directions, namely lateral (Lat), head pin (Lng), dorsoventral (Vrt), roll, pitch, and rotation (Rtn). Then, the plan isocenter was redetermined according to the setup error data. Moreover, the dose distribution was recalculated without changing the radiation field parameters. Finally, the V40, Dmean, D98% and D2% of both PTV and CTV and the Dmean, D20 cm 3, and D30 cm 3 of scalp tissue were evaluated. Results:When patients were treated with TTF concurrent radiotherapy wearing TTF arrays, the setup errors increased by 2 mm and 1.3 mm on average (maximum: 3.5 mm and 2.7 mm) toward the foot and dorsal directions, respectively. In addition, the setup errors in both Roll and Rtn directions increased by about 1.1° toward one side. The V40 and D98% of PTV decreased by up to 4.78% and 6%, respectively. The Dmean, D20 cm 3, and D30 cm 3 to scalp tissue increased by up to 2.6%, 3.2%, and 3.5%, respectively. The errors of other dose parameters for both CTV and PTV were within 2%. Conclusions:TTF arrays have significant effects on the setup errors of patients in the Lng and Vrt directions and increase the setup difficulty in the Roll and Rtn directions, while there is no significant error in the Lat and Pitch directions. Moreover, too large setup errors can significantly reduce the dose to PTV.

Use of magnetic resonance scanner with a linear accelerator during precision radiotherapy for breast cancer / 中华放射肿瘤学杂志

Magnetic resonance-guided radiotherapy (MRgRT) not only offers real time magnetic resonance (MR) imags with high-resolution and good soft tissue contrast to guide the delineation of the target volume during simulation and daily radiotherapy, but also reveals the position and shape changes of the target volumes and organs at risk (OAR) during treatment dynamically, which provides the evidence for the individual-adptive planning revision. Thus, MRgRT has the potential to dramatically impact cancer research and treatment. And this treatment mode is theoretically more suitable for the disease with obvious tissue deformation, such as breast. In this review, application of MR scanner with a linear accelerator (MR-linac) in radiotherapy workflows for breast cancer patients was summarized, and its implications and opportunities on breast cancer irradiation were highlighted.

Significance of target volume delineation of tumor bed according to metal clips or seroma in determing tumor bed position during radiotherapy after breast-conserving surgery for breast cancer / 肿瘤研究与临床

Objective:To investigate the differences between the mental clips placed intraoperatively and the tumor bed's target volume delineation of seroma based on CT scanning during radiotherapy for breast cancer patients who received breast-conserving surgery in the persuit of a better solution to determine the tumor bed position.Methods:The clinical data of 13 patients with early breast cancer who received postoperative radiotherapy after breast-conserving surgery at Beijing Shijingshan Hospital and Beijing Shijitan Hospital of Capital Medical University from December 2020 to January 2022 were retrospectively analyzed. They all had surgical clips implanted during the surgery. The following methods were used to delineate the target volume of tumor bed, including gross target volume delineation of tumor bed based on the mental clips (GTVtb-Clip), the tumor bed's gross target volume delineation of seroma based on CT scanning (GTVtb-Seroma), and the combination of both (GTVtb-C+S). The volume, diameter on three coordinate axis, neutral point displacement and conformability of these delineation methods were compared.Results:The volume of GTVtb-Clip, GTVtb-Seroma and GTVtb-C+S was (25±10) cm 3, (38±17) cm 3, (49±20) cm 3, and the differences were statistically significant (all P<0.05). The diameter on X axis was (4.7±1.2) cm, (5.3±1.4) cm, (5.7±1.6) cm, respectively in GTVtb-Clip, GTVtb-Seroma and GTVtb-C+S; the diameter on Y axis was (4.6±1.7) cm, (5.0±1.6) cm, (5.7±1.7) cm, respectively in GTVtb-Clip, GTVtb-Seroma and GTVtb-C+S; the diameter on Z axis was (4.4±1.5) cm, (5.2±1.4) cm, (5.6±1.4) cm in GTVtb-Clip, GTVtb-Seroma and GTVtb-C+S. The differences in the diameter of GTVtb-Clip and GTVtb-C+S on X,Y, Z axis were statistically significant (all P<0.05); the differences in the diameter of GTVtb-Seroma and GTVtb-C+S on X, Z axis were statistically significant (all P<0.05); the difference in the diameter of GTVtb-Clip and GTVtb-Seroma on X axis was statistically significant ( P<0.05) .Neutral point displacement was (5.8±1.6) cm, (5.5±1.9) cm, (6.0±1.7) cm, respectively of GTVtb-Clip, GTVtb-Seroma, GTVtb-C+S, and the difference was not statistically significant ( P>0.05). Conformability of GTVtb-Clip and GTVtb-Seroma, GTVtb-Clip and GTVtb-C+S, GTVtb-Seroma and GTVtb-C+S was 0.412±0.112, 0.525±0.095, 0.774±0.112,respectively, and the differences were statistically significant (all P<0.05). Conclusions:During radiotherapy after breast-conserving surgery for breast cancer, compared with the single method, the combination of GTVtb-Clip and GTVtb-Seroma can better cover the real tumor bed, thus reducing the omission of tumor bed and recurrence rate. CT position should better take place at 4 to 8 weeks for patients receiving radiotherapy after breast-conserving surgery, and target volume of tumor bed will be delineated based on the postoperative changes of both mental clips and seroma.

Effect of cone-beam computed tomography image-guidance on the setup errors of stereotactic body radiotherapy for spinal metastatic tumors / 肿瘤研究与临床

Objective:To evaluate the effect of image-guided with cone-beam computed tomography (CBCT) based on volumetric modulated arc therapy (VMAT)-flattening filter free (FFF) on the setup errors of stereotactic body radiotherapy (SBRT) in patients with spinal metastatic tumors.Methods:The clinical data of 15 patients with spinal metastatic tumors who underwent SBRT in Jilin Cancer Hospital from August 2020 to January 2022 were retrospectively analyzed. The radiotherapy dose of bone metastasis was 32 Gy per 4 times and CBCT scanning was performed before and after radiotherapy. Every patient received radiotherapy 4 times; all 15 patients underwent SBRT 60 times in total and 120 CBCT volume images were finally obtained and analyzed. The systematic error (Σ) and random error (σ) were calculated at different correction threshold levels. The translational setup error and rotational setup error at the left-right (X axis), head-foot (Y axis) and front-back (Z axis) directions before and after radiotherapy were compared, which were expressed as Σ ± σ.Results:The pre-SBRT and post-SBRT translational setup errors were (0.14±0.27) cm and (0.07±0.19) cm, respectively ( P<0.001) in the X direction, (-0.05±0.33) cm and (0.00±0.19) cm, respectively ( P = 0.001) in the Y direction, (-0.13±0.19) cm and (-0.02±0.14) cm, respectively ( P = 0.012) in the Z direction. The pre-SBRT and post-SBRT rotational setup errors were (-0.31±0.76)° and (-0.09±0.34)°, respectively ( P < 0.001) in the X direction, (-0.13±0.88)° and (-0.07±0.36) °, respectively ( P < 0.001) in the Y direction, (0.10±0.51)° and (0.16±0.38)°, respectively ( P < 0.001) in the Z direction. Conclusions:CBCT correction could reduce Σ and σof the translational setup and rotational setup, increase the accuracy of SBRT based on VMAT-FFF for patients with spinal metastatic tumors.