An inverse Jiles-Atherton model of nanocrystalline magnetic core for nanoseconds square pulsed magnetization

The magnetic core is a key component of a linear transformer driver (LTD), and the accuracy of the core model affects the calculation of the LTD power flow and the prediction of the output waveform. In this paper, a magnetization model based on the inverse Jiles-Atherton (inverse J-A) model is developed and a particle swarm algorithm is used to identify the parameters and to obtain the variation of the parameters with the excitation characteristic. A nanoseconds square wave LTD magnetic core test platform was built to obtain the magnetization characteristics of nanocrystalline magnetic cores under different excitation characteristic parameters. Under square wave pulses, due to the presence of harmonic components, core loss is more complex. In view of the fitting deviation caused by the traditional J-A model not considering harmonic factors and anisotropy, a dynamic loss correction factor is proposed. Through a comparison of experimental and simulation results, this model can well reflect the magnetization process and has high accuracy in fitting dynamic hysteresis loops and predicting losses, which is important for guiding the design of a square pulse LTD.

Dosimetric Analysis of CBCT-Based Weekly Online Adaptive Radiotherapy for Locally Advanced Non-Small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

Anatomic and geometric changes are common during a radiotherapy course amongst patients receiving conventional fractionated radiotherapy for locally advanced non-small cell lung cancer (LA-NSCLC). These changes may cause significant deviation from initial reference plan resulting in over-treatment of normal tissue or under-coverage of the target. Cone-beam computed tomography (CBCT)-based online adaptive radiotherapy (ART) platforms allow for response to these changes and is being increasingly used in the clinic though less so for intrathoracic disease. We hypothesized weekly CBCT-ART would improve target coverage and decrease dose to organs at risk (OAR) in patients with LA-NSCLC.

MATERIALS/METHODS

Data was collected from a prospective registry of 23 LA-NSCLC patients treated to 60 Gy in 30 fractions with CBCT-ART between June 2021 and December 2022. For weekly ART (Wk-ART), online plan adaptation started on week two. The adapted plan was then used to treat patients with image guidance until the next ART. For comparison, doses were recalculated with the initial reference plan on the SCT with updated contours to derive non-adapted (non-ART) dosimetry for each week. The final dosimetric parameters were obtained by averaging weekly coverage (ITV, PTV) and critical OAR (Lung, esophagus, heart, spinal cord) doses for non-ART and weekly ART treatments respectively for each patient. Paired student t-test was performed to compare the dosimetric parameters between non-ART and Wk-ART.

RESULTS

We observed an average 29% ± 19% (median: 26%) reduction in ITV volume through the radiotherapy course, with 48% (11/23) of patients showing >30% reduction. Most significant volume reductions (16%) were observed between the third and fourth adaptation. Weekly ART showed significant (p<1×10-3) improvements in ITV and PTV coverage, and showed improved clinically relevant lung, esophageal, cardiac, and lung dosimetry (Table 1), especially in the later stages of treatment when the tumor showed significant shrinkage. The average time from contour review to quality assurance completed is 8.5±1.2 min.

CONCLUSION

CBCT-ART provides robust ART plan quality and efficient workflow. There are significant improvements in target coverage and OAR sparing in LA-NSCLC treated with weekly CBCT-ART and these are driven by the significant volume reduction of the ITV throughout treatment course.

Concurrent Radiation and Deep Hyperthermia Therapy for the Treatment of Recurrent Prostate Cancer

PURPOSE/OBJECTIVE(S)

Robustpreclinical and clinical data have established hyperthermia as an effective radiosensitizer which can be used in the setting of recurrent disease to enhance the therapeutic window. We present a single institution experience examining outcomes in recurrent prostate cancer (RPCA) patients treated with concurrent deep hyperthermia (DHT) and radiation (RT). We hypothesized that concurrent DHT and RT would be well tolerated and would provide durable local control without unexpected toxicity.

MATERIALS/METHODS

Consecutive RPCA patients treated with concurrent DHT and pelvic RT were retrospectively analyzed. Patients received twice weekly DHT treatments in addition to daily or twice daily (BID) RT. DHT was delivered using a concentric ring radiofrequency phased array system to a target temperature of 40-43°C. Acute and late treatment associated toxicities, graded per Common Terminology Criteria for Adverse Events (CTCAE) v5.0, were evaluated. Survival and control outcomes were evaluated using the Kaplan-Meier method.

RESULTS

Eighteen patients were included for analysis. Median patient age was 69 yrs (64-82 yrs). Fifteen (83%) patients had received prior RT and 12 (67%) patients had undergone radical prostatectomy. At time of treatment, two patients had RPCA which had dedifferentiated to a small cell phenotype. Eight (44%) patients had extra-pelvic disease at time of treatment. Seventeen (94%) patients received proton RT, while 1 (6%) received photon RT. Median RT dose was 49 Gy (range 30-73.8 Gy). Five (28%) patients received BID RT. Fifteen (83%) patients also received sequential or concurrent systemic therapy including androgen deprivation therapy or chemotherapy. A total of 142 DHT treatments were administered (median of 7.5 treatments). Fourteen (78%) patients completed ≥ 75% of planned DHT treatments. Reasons for inability to complete treatment included discomfort and abnormal vital signs during DHT. Only one patient reported Grade 2 pain and pruritus attributed to concurrent RT and DHT. One acute Grade 3 RT toxicity (diarrhea) was reported. No late Grade 3+ toxicities occurred. Of ten patients (56%) treated with curative intent, 8 (44%) had no reported failures at 2-year follow up while two had distant failure and biochemical failure respectively. Three (17%) patients were treated with palliative intent for disease related pain; two reported partial relief and one reported complete pain relief. With a median follow-up of 27 months (1-46 months), 2-year failure free survival was 41.4% (95% CI: 27.8-55%), local control was 76.5% (95% CI 66.2-86.8%) and overall survival was 70.9% (95% CI 58.4-83.3%).

CONCLUSION

Our results suggest that concurrent RT and DHT is well tolerated and allows for safe escalation of local therapy for RPCA, providing patients with durable local control and palliation with an acceptable toxicity profile. Prospective validation is warranted.

Predicted Cardiac Toxicity in Daily Cone-Beam CT-Based Online Adaptive Stereotactic Partial Breast Irradiation with Decreased PTV Margins

PURPOSE/OBJECTIVE(S)

Partial breast irradiation (PBI) targets a smaller volume over less time compared to whole breast radiation, but the organ-at-risk (OAR) sparing allowed by its large (up to 1 cm) PTV can be improved. The heart is sensitive to low doses with conventional fractionation and NTCP models have been created for heart substructures. We hypothesized that daily online adaptive stereotactic PBI (A-SPBI) IMRT with 3-mm PTV improves dosimetry and predicted cardiac toxicity risk.

MATERIALS/METHODS

Patients treated with daily CBCT-based online A-SPBI IMRT were excluded if the minimum heart dose was <1 Gy. IMRT radiation plans with 3-mm PTV margins were recreated with 1-cm margins per the Florence APBI IMRT trial planning guideline. Dose statistics were converted to the equivalent doses in 2-Gy fractions (EQD2) using α/β = 3 for use in NTCP models and for comparison using paired t tests, with differences considered significant if p≤0.05.

RESULTS

The table details heart, left anterior descending artery (LAD), and left (LV) and right ventricle (RV) EQD2 statistics for 4 left-sided and 4 right-sided 3-mm PTV plans and their 1-cm PTV replans. For 2 patients with non-zero LV V5, 9-year excess cumulative risk of acute coronary event was <0.001% for both margin sizes. No plan reached thresholds for increased risk of non-cardiac death, major adverse cardiac event, or >10% decrease in LV ejection fraction.

CONCLUSION

Given the established relationship between low MHD and cardiac events, the significant decrease in MHD revealed in comparisons of 3-mm and 1-cm PTV A-SPBI plans of our first 8 patients is promising; we expect the forthcoming larger sample size to show significant differences in substructure doses. NTCP models created for non-IMRT breast plans and targets with higher heart exposure did not predict clinically-relevant differences in cardiac risk. NTCP model development for the low heart dose achieved with A-SPBI would define expected benefit in these patients; in their absence, daily adaptation should be considered in patients with unfavorable anatomy or cardiac risk factors.

Computational explorations of the interaction between laccase and bisphenol A: influence of surfactant and different organic solvents

Bisphenol A (BPA), as an environmental endocrine disruptor can cause damage to the reproductive, nervous and immune systems. Laccase can be used to degrade BPA. However, laccase is easily deactivated, especially in organic solvents, but the specific details are not clear. Molecular dynamics simulations were used to investigate the reasons for changes in laccase activity in acetonitrile (ACN) and dimethyl formamide (DMF) solutions. In addition, the effects of ACN and DMF on the activity of laccase and surfactant rhamnolipid (RL) on the degradation of BPA by laccase were investigated. Results showed that addition of ACN changed the structure of the laccase, not only decreasing the van der Waals interaction that promoted the binding of laccase with BPA, but also increasing the polar solvation free energy that hindered the binding of laccase with BPA, so it weakened the laccase activity. DMF greatly enhanced the van der Waals interaction between laccase and BPA, and played a positive role in their binding. The addition of surfactant RL alleviated the effect of organic solvent on the activity of laccase by changing the polar solvation energy. The mechanism of surfactant RL affecting laccase activity in ACN and DMF is described, providing support for understanding the effect of organic solvents on laccase.

Assessment of Cardiac Radiation Dose in the Co-60 Prone Based Stereotactic Partial Breast Irradiation (CP-sPBI) Using the Distance from the Heart to the Planning Treatment Volume as a Surrogate Marker

PURPOSE/OBJECTIVE(S)

Irradiation of the breast has shown to provide sharp dose gradients using Co-60 prone based stereotactic partial breast irradiation (CP-sPBI), a contemporary device for stereotactic radiotherapy for breast cancer (BC) for accelerated partial breast irradiation (APBI). In addition, the precise setup of CP-sPBI permits a small planning treatment volume (PTV) margin of 3 mm creating a greater distance from PTV to organs at risk. However, to date the factors that influence dose gradients and subsequent cardiac doses of ionizing radiation using CP-sPBI have not been well-studied. Here we evaluate distance of the heart to the lumpectomy PTV cavity and how this effects cardiac dose.

MATERIALS/METHODS

A retrospective database of 113 consecutive patients treated by CP-sPBI for APBI from March 2019 to February 2023 who were treated with 30 Gy in 5 fractions were queried for analysis. The minimum distance from the heart to the PTV (hP) was measured in either the axial or sagittal view. A group of 28 patient cases were randomly selected to achieve an even distribution of 28 cases with hP < 2.75 cm and hP ≥ 2.75 cm to compare cardiac toxicities based on hP. Descriptive analyses were performed to evaluate various cardiac dosimetric parameters based on laterality of BC and hP, using the student's t test.

RESULTS

The mean (range) hP was 4.58 cm (0.80-12.23) for all cases. The subgroup analyses of 28 patient cases with cardiac parameters showed the heart mean (range) dose of 1.20 Gy (0.01-2.11). The mean and max heart dose to the left-sided BC were similar to those to the right-sided BC (mean dose: 1.20 vs. 1.19 Gy; P = 0.97 and max dose: 10.47 vs. 5.66 Gy; P = 0.06). An inverse correlation between hP and mean heart dose was shown with the correlation coefficient of -0.81. Using a cutoff of 2.75 cm hP, the differences between hP < 2.75 and hP ≥ 2.75 cm for all cardiac dosimetric evaluations were all statistically significant, including mean (1.67 vs. 0.79 Gy; p<0.01) and maximal heart dose (14.48 vs. 4.11 Gy; p<0.01) CONCLUSION: CP-sPBI treatment delivery system was able to achieve acceptable clinically relevant heart dosimetric parameters when delivering 5 fraction APBI with a mean heart dose of 1.20 Gy for all locations of PTV cavity volume in the breast. Due to CP-sPBIs excellent dose fall-off characteristics, APBI using CP-SPBI showed clinically acceptable cardiac dosimetric parameters, particularly for PTVs located > 2.75 cm from the heart.

Observed and Predicted Toxicity in Daily Cone-Beam CT-Based Online Adaptive Stereotactic Partial Breast Irradiation with Decreased PTV Margins

PURPOSE/OBJECTIVE(S)

Accelerated partial breast irradiation (APBI) delivers smaller radiation volumes over less time compared to whole breast irradiation (WBI), but the organ-at-risk (OAR) sparing allowed by its large (up to 1 cm) planning target volume (PTV) can be improved. PTV can be decreased with daily online adaptive planning, which we hypothesized yields low rates of adverse events observed and predicted by normal tissue complication probability (NTCP) models.

MATERIALS/METHODS

Intensity-modulated (IMRT) cone-beam CT (CBCT)-based daily online adaptive stereotactic PBI (A-SPBI) plans with 3-mm PTV from 8 patients were recreated with 1-cm PTV per the Florence APBI IMRT trial planning guideline. Dose statistics with evidence for association with toxicity were compared. Documented toxicities were collected for patients treated with A-SPBI with a minimum follow-up of 3.5 months and Common Terminology Criteria for Adverse Events (CTCAE) v.5.0 grade was assigned. Using α/β = 3 for breast and lung, dose statistics were converted to equivalent doses in 2-Gy fractions (EQD2) for use in NTCP models and for comparison using paired t tests, with differences considered significant if p≤0.05.

RESULTS

The table details EQD2 dose statistics for breast, lung, and cosmetic toxicity for A-SPBI plans with 3-mm PTV and their 1-cm PTV re-plans in 8 patients. PTV volume, mean lung dose (MLD), and lung V5, V20, and V30 were significantly lower in 1-cm plans. Acute, subacute (3-6 months), and late toxicities were collected for 30 patients followed for a median of 8 months (range 4-13 months). Radiation dermatitis was the most common acute toxicity (n = 16, 53%), followed by hyperpigmentation (n = 12, 40%), fibrosis (n = 9, 30%), and fatigue (n = 9, 30%). One grade 3 radiation dermatitis was the only grade ≥3 toxicity. Six patients (20%) acutely developed breast or axillary edema: 4 (13.3%) resolved, and 2 (6.7%) developed acutely and persist at last follow-up, >6 months after RT. No patient had a lung V20, V30, or MLD meeting thresholds for radiation-induced lung injury, radiation pneumonitis, or symptomatic or imaging-based pneumonitis models, respectively. The breast V55 model predicted a median risk of unfavorable cosmesis of 33% (range 26-44%) for A-SBPI plans and 35% (range 28-51) for 1-cm PTV plans (p = 0.28).

CONCLUSION

Observed acute toxicities are tolerable and rarely persist in patients treated with A-SPBI with 3-mm PTV margins with daily CBCT-based online adaptation. NTCP modeling predicts similar cosmetic outcome to 1-cm margins. The significant reduction in ipsilateral lung dose with a 3-mm PTV in our first 8 patients especially supports daily adaptation in low-risk breast cancer patients with smoking history and/or lung comorbidity.

Complexity Metrics and Planning Dose-Based Pretreatment Patient-Specific Quality Assurance Prediction: Classification, Gamma Passing Rates, and DVH Deviation

PURPOSE/OBJECTIVE(S)

Patient-specific quality assurance (QA) prediction before treatment is beneficial to the clinical resource allocation and the dosimetric monitoring of the patient plans. The aim of this study is to investigate the potential of complexity metrics of radiotherapy plan and patient planning dose to predict QA result, gamma passing rates and dose-volume indices deviation.

MATERIALS/METHODS

Planning dose from treatment planning system (TPS), reconstructed dose from a vendor provided QA phantom and complexity metrics of the 499 radiotherapy plans of patients in our institution from March 2022 to September 2022 were used for methodology verification. Gamma passing rate (3%/2mm,10% threshold) 90% was regarded as criterion of QA pass or fail. A deep learning model ResNet-50 was modified to 3D dose processing and a multilayer perceptron (MLP) with three layers were adopted to extract features from 3D dose and 1D metrics in two parallel ways, then, the features were concatenate together to predict QA results. The dataset was split into 349 for train, 50 for validation and 100 for testing. Evaluation of predictions was based on absolute value deviation and area under the curves (AUC) of receiver operator characteristic (ROC) curve.

RESULTS

In this dataset, 71% (355/499) plans pass the pretreatment QA test. For QA passing prediction in 100 testing cases, the AUC of ROC could achieve 0.92. For gamma passing rates prediction, a mean absolute error (MAE) of 1.8% could be observed for cases with gamma passing rates bigger than 90%, and a MAE of 4.5% deviation could be observed for cases with gamma passing rates from 80% to 90%. For PTV ΔD95 (%) and PTV ΔHI (%), the MAE of prediction and ground truth is 1%. The model with only complexity metrics and only 3D dose could achieve the AUC of ROC 0.91 and 0.84, respectively.

CONCLUSION

The complexity metrics and 3D planning dose-based model could predict pretreatment patient specific QA results with high accuracy and the complexity metrics play a leading role in the model. Dose-volume metrics deviations of PTV could be predicted and more clinically useful information could be provided.

Impact of Surveillance Imaging in Patients with HPV-Associated Oropharyngeal Carcinomas Treated with Definitive Radiation and Chemotherapy

PURPOSE/OBJECTIVE(S)

Post-treatment surveillance imaging for HPV-associated oropharyngeal carcinomas (OPCs) differs among physicians and institutions. Surveillance imaging can detect disease progression earlier, but can also contribute to anxiety and cost, without proven disease-free or survival benefit. We sought to determine the number of surveillance scans needed to detect a recurrence in patients with HPV-associated OPCs.

MATERIALS/METHODS

We included consecutive patients with locally advanced HPV-associated OPC that received definitive concurrent chemoradiotherapy (CRT) with 70 Gy between March 1, 2017 to July 31, 2019. First post-treatment scans were defined as the first scans following the end of CRT. Surveillance scans were defined as body FDG PET/CTs, neck or chest CTs, and neck MRIs taken after the first post-treatment scans showed no evidence of disease. Any scans ordered to follow suspicious lesions on first post-treatment scans were not counted as surveillance scans. Recurrences were classified as detected by first post-treatment scans, surveillance scans, clinical exam, or incidental findings. The number of surveillance scans needed to detect 1 recurrence was determined by dividing the number of surveillance scans by the number of recurrences detected by surveillance scans.

RESULTS

There were a total of 275 patients with median follow-up of 39.8 months (Interquartile Range (IQR), 34.9-47.8). Surveillance scans were first taken at a median of 12.1 months (IQR, 9.2-16) post-CRT. There were 27 (9.8%) patients who had a recurrence: 7 (2.5%) had locoregional recurrence (LR), 19 (6.9%) had distant metastasis (DM), and 1 (0.4%) had both LR and DM. LR was detected at a median of 5.8 months (IQR, 3.4-10.6) post-CRT and DM was detected at a median of 9.5 months (IQR, 4.8-14.3) post-CRT. Of all recurrences, 11/27 (40.7%) were first post-treatment scan detected, 10 (37.0%) were surveillance scan detected, 5 (18.5%) were clinical exam detected, and 1 (3.7%) was incidentally detected on lung cancer screening. Four (50%) LRs were first post-treatment detected (median time to detection, MTD: 4.2 months), 3 (37.5%) were clinical exam detected (MTD: 6.7 months), and 1 (12.5%) was surveillance detected (MTD: 9.0 months). For DM, 9 (45%) were surveillance detected (MTD: 12.7 months), 8 (40%) were first post-treatment detected (MTD: 4.1 months), 2 (10%) were clinical exam detected (MTD: 18.9 months), and 1 (5%) was incidentally detected (MTD: 12.1 months). A total of 702 surveillance scans were taken during the follow-up period. The number of surveillance scans needed to detect 1 LR/DM was 71 overall, 50 within 2 years and 254 beyond 2 years from CRT.

CONCLUSION

First post treatment scans detect most recurrences for HPV-associated OPC. A high burden of surveillance scans is needed to detect one recurrence, especially beyond 2 years from CRT.

Dosimetric Comparison of Adaptive Radiotherapy Modalities for Stereotactic Partial Breast Irradiation

PURPOSE/OBJECTIVE(S)

An increase in the availability of adaptive radiotherapy (ART) platforms have proven to be effective in the treatment of a variety of sites. In this study, we aim to evaluate the effectiveness of non-adaptive RT and 3 different ART platforms: (1) CBCT-based, (2) CT-based, and (3) MRI-based for stereotactic partial breast irradiation (SPBI).

MATERIALS/METHODS

Data were collected from 32 patients (16 left and 16 right breast) treated at a single institution. 16 patients (8 left and 8 right) treated using the non-ART platform were re-planned onto two different ART platforms, CBCT- and MRI-based. The remaining 16 patients treated using CT-based adaptive platform were not re-planned due to the prone patient treatment position (others systems supine). All cases were planned to 30 Gy in 5 fractions. Plan quality was evaluated based on pre-defined planning goals to the OARS: ipsilateral and contralateral lungs (Dmean, Dmax, V20 Gy, V9 Gy), ipsilateral (V15 Gy, V30 Gy) and contralateral breasts (Dmax), heart (Dmean, Dmax, V3 Gy, V1.5 Gy), skin (Dmax, V36.5 Gy), and rib (Dmax, V30 Gy). Target goals were defined by Dmax, Dmin, gradient index, and paddock conformality index. Re-planned cases were compared within the cohort using a paired t-test and a 2-sided t-test was used comparing to the CT-based platform.

RESULTS

Comparing the left and right breast cohort across all platforms, the CT-based ART system showed a signification dose reduction in Dmean (p<0.001 for all platforms), Dmax (p<0.001 for left breast, p<0.03 for right breast) and V9 Gy (p<0.004 for left breast, p<0.001 for right breast) to the ipsilateral lung, V15 Gy (p<0.004 for left breast cohort) to the ipsilateral breast, and Dmax to the contralateral breast (p<0.001) and ribs (p = 0.01, p<0.001, p = 0.01 for CBCT-ART, MRI-ART, and non-ART for left breast cohort only). On average, the MR-Linac platform showed the least degree of OAR sparing across nearly all dosimetric parameters evaluated when compared to all modalities, especially for contralateral lung Dmean and Dmax (p<0.05 for all dosimetric parameters for all platforms) and contralateral breast Dmax (p<0.003 for all platforms). The CBCT-based platform showed superior dose reduction in contralateral lung mean (p<0.03 for all platforms) and heart Dmean (p = 0.065, p<0.001, p = 0.045 for non-adaptive, MRI-ART, and CT-ART for left breast and p<0.008 for right breast). PTV coverage was comparable across all platforms, averaging at approximately 95%. The CT-based ART platform showed a significantly reduced gradient index relative to the CBCT- and MRI-based platforms (p<0.001).

CONCLUSION

For SPBI treatments, the CT-based ART platforms displayed a higher degree of OAR sparing for many of the dosimetric parameters recorded relative to the other ART and non-ART platforms presented. The MRI-based system typically showed less reduced OAR sparing; however, the advantage of the system is shown if soft tissue contrast is needed. PTV coverage remained comparable across all platforms.

Tumor Regression with 5-Aminolevulinic Acid (5-ALA)-Mediated Radiodynamic Therapy (RDT) Using Different Megavoltage Energies

PURPOSE/OBJECTIVE(S)

5-aminolevulinic acid (5-ALA) accumulates in target tumor cells, where it is metabolized to a photosensitizer - protoporphyrin IX (PpIX). Cherenkov light induced by high-energy photon beams effectively activates the PpIX due to the Soret band. The activated photosensitizers lead to cellular toxicities to kill malignant tumor cells by converting surrounding tissue oxygens into singlet oxygens. Radiodynamic therapy (RDT) utilizes cellular damage caused by both radiation dose and activated photosensitizer. The emission of Cherenkov light was observed higher with higher energy irradiation in phantom and ex-vivo tissues. Therefore, using an in-vivo mouse model, this study aimed to investigate the efficacy and energy dependency of RDT combined with 5-ALA and different ranges of megavoltage photon irradiation.

MATERIALS/METHODS

In order to investigate individual and synergistic effects of 5-ALA administration and radiation treatment, the tumors (n = 344) were randomized into eight groups: control (untreated), 5-ALA only, 6-, 15-, and 45-MV conventional radiation treatment (RT) only, 6-, 15-, and 45-MV RDT. 4 Gy in a single fraction was delivered to the tumors using three different energy photons for RT only and RDT groups. 5-ALA was systemically injected into 5-ALA only and RDT groups at 100 mg/kg by tail-vein 4 hours before irradiation for endogenous PpIX accumulation in the tumor. Tumor growth was measured using a 1.5 T MR scanner on the day of treatment (prior to the treatment), 3, 7, and 14 days post-treatment. Two-way repeated ANOVA with Bonferroni correction was used to compare each treatment group to determine the statistically significant difference in tumor growth.

RESULTS

A total of 45 MV RDT resulted in the most significant decrease in tumor growth by 58.8 ± 3.4 %, 58.0 ± 3.0 %, and 55.0 ± 3.0 % compared to 5-ALA, 45 MV RT, and control group on 7 days post-treatment (P<0.001), respectively. Moreover, a synergistic effect of 45 MV RDT causes a 47.1-54.1 % additional decrease in tumor growth toward the effective treatment outcome. Compared to the different energies, 45 MV RDT resulted in a 52.2 ± 3.1 % and 19.7 ± 7.2 % decrease in tumor growth compared to 6 MV RDT and 15 MV RDT on 7 days post-treatment, respectively (P<0.001), whereas the conventional RT was not.

CONCLUSION

Radiodynamic therapy using 5-ALA administration and 45MV photon beam irradiation resulted in the most significant tumor growth control. A photon energy dependency was observed in radiodynamic therapy. 45MV photon beams showed greater in activating PpIX, improving the synergistic effects of radiation dose and activated photosensitizer than the other energies. The preliminary results provide a foundation for new innovative treatment strategies that have the potential to improve cancer treatment.

Investigation of Hydrogen Peroxide for 45MV 5-Aminolevulinic Acid-Mediated Radiodynamic Therapy

PURPOSE/OBJECTIVE(S)

Cytotoxicity caused by the reactive oxygen species (ROS), such as singlet oxygen species (1O2), superoxide radical (O2-), and hydroxyl radical (HO), is a mechanism for treating cancer cells in radiation therapy. 5-aminolevulinic acid (5-ALA)-mediated radiodynamic therapy (RDT) is more effective in killing tumor cells than conventional radiation therapy. ROS is produced not only by ionizing radiation but also by Cherenkov light-activated protoporphyrin IX (PpIX), which is metabolized endogenously from 5-ALA. Moreover, PpIX also catalyzes hydrogen peroxide to generate 1O2, and an enhanced catalytic yield of 1O2 was observed in X-ray irradiation in vitro. Therefore, using an in-vivo mouse model, this study aimed to investigate the effect of hydrogen peroxide as a coenzyme catalyst on a novel 45MV 5-ALA-mediated RDT.

MATERIALS/METHODS

A subcutaneous C57BL/6 mouse model of KP1 cell line was used. The tumors (n = 240) were randomized into six groups, consisting of untreated, conventional radiation treatment (RT), and RDT with or without hydrogen peroxide: 1. control (untreated), 2. hydrogen peroxide, 3. 45MV RT, 4. 45MV RT + hydrogen peroxide, 5. 45MV RDT, 6. 45MV RDT + hydrogen peroxide. For 45MV photon irradiation, a single fraction of 4 Gy was delivered to the tumors. 5-ALA was systemically injected at 100 mg/kg by tail-vein 4 hours before the treatment for endogenous PpIX accumulation in the tumor. Carbamide peroxide was used to deliver hydrogen peroxide to tissue and was administered at 60 mg/kg intratumorally into tumors ∼3-5 min before the treatment. The treatment effect of a single fraction of treatment was measured by calculating tumor growth, measured using a 1.5 T MR scanner on the day of treatment (prior to the treatment), 3 and 7 days post-treatment. Two-way repeated ANOVA with Bonferroni correction was used to compare each treatment group to determine the statistically significant difference in tumor growth.

RESULTS

A total of 45MV RDT with hydrogen peroxide was shown to significantly delay the tumor growth for the mouse model and cell line investigated in this work. 45MV RDT with hydrogen peroxide group resulted in a decrease in tumor growth by 51.3 ± 4.1 % and 56.1 ± 5.1 % compared to the control group on 3 and 7 days post-treatment, respectively (P<0.001), and 43.4 ± 0.8 % and 50.9 ± 0.8 % compared to 45MV RT alone on 3 and 7 days post-treatment, respectively. Moreover, the enhancement effect of hydrogen peroxide on 45MV RDT was 2.2-4.7 times greater on 45MV RT alone (P<0.05). Hydrogen peroxide did not contribute to tumor growth when administered alone.

CONCLUSION

A total of 45MV 5-ALA-mediated RDT with hydrogen peroxide resulted in the most significant tumor growth delay compared to the other groups. The catalytic effect of PpIX and hydrogen peroxide was observed in-vivo. These preliminary results demonstrate an effective cancer treatment modality.

[Clinical efficacy analysis of arthroscopic treatment for hallux ganglion cyst deriving from ankle joint]

Objective: To investigate the pathogenesis and clinical efficacy of arthroscopic treatment for hallux ganglion cyst deriving from ankle joint. Methods: The clinical data of 21 patients with ankle arthroscopic in the Department of Hand and Foot Surgery,Affiliated Hospital of Jining Medical College from January 2019 to March 2021 were analyzed retrospectively.There were 15 male and 6 female cases,aged (52.6±8.2) years (range:42 to 70 years).There were 9 cases of primary operation and 12 cases of recurrence after operation in other hospital.All the patients were examined by ankle arthrography and MRI before operation.The synovial membrane of the ankle was debrided and the tendon sheath of flexor longus was removed at the ankle canal.One year after operation,MRI was performed,and the American Orthopedic Foot and Ankle Society(AOFAS) score of forefoot function and visual analogue scale (VAS) before and after operation were compared by the paired t test or Mann-Whitney U test.The postoperative complications and recurrence were recorded. Results: All patients were operated successfully.The joint capsule at the back of the ankle joint of the patients were ruptured and communicated with the tendon sheath of the flexor longus tendon at the ankle canal.No wound infection,vascular and nerve injury occurred.The follow-up period was (15.0±2.2) months (range:12 to 18 months).During the follow-up period,there was no recurrence of toe appearance and MRI.At the last follow-up,the AOFAS score (90.8±4.3) was significantly higher than that (72.8±6.3) before operation (t=-10.810,P<0.01),and the VAS score(M(IQR)) was significantly lower than that before operation,the difference was significant (1.0(1.0) vs. 3.0(0.5), Z=-4.081,P<0.01). Conclusions: The possible mechanism of hallux ganglion cyst deriving from ankle joint is that the joint capsule at the back of the ankle joint ruptures and communicates with the tendon sheath of the flexor longus tendon at the ankle canal,and the intra-articular synovial fluid through the cylinder effect generated by sliding with the flexor tendon of the flexor longus tendon in the tendon sheath sac leads to the heel valange cyst.Ankle-synovial cleansing of the ankle joint under ankle arthroscopy and resection of the flexor tendon sheath of the flexor longus tendon at the ankle canal are effective and less invasive.

[Clinical effects of expanded flaps in reconstructing scar contracture deformities in the face and neck after extensive burns]

Objective: To investigate the clinical effects of expanded flaps in reconstructing scar contracture deformities in the face and neck after extensive burns. Methods: A retrospective observational study was conducted. From May 2016 to September 2022, 17 patients with scar contracture deformities in the face and neck after extensive burns were admitted to Tongren Hospital of Wuhan University & Wuhan Third Hospital, including 13 males and 4 females, aged 23 to 55 years, with 3 patients having degree Ⅱ cervical contracture, 14 patients having degree Ⅲ cervical contracture, and 12 patients having facial scar contracture deformity. In the first stage, 34 rectangular skin and soft tissue expanders (hereinafter referred to as expanders) with rated capacity of 100-600 mL were inserted into the face, chest, shoulder, and abdomen, and then the normal saline was injected for expansion. In the second stage, the scar tissue was removed and the contracture was released to correct the deformity. Two expanded facial flaps were transplanted in local fashion, 17 expanded flaps were transplanted in pedicled fashion, and 15 expanded flaps were freely transplanted to repair the secondary wounds after release, with artery pressurization was performed in 7 flaps. Indocyanine green fluorescence imaging was used to evaluate the arterial blood perfusion and venous return of the flaps during transplantation. The incision area of 32 flaps except 2 facial flaps was 10 cm×8 cm-36 cm×16 cm. The wounds of 31 flap donor sites were closed by direct suture, and the wound of 1 flap donor site was repaired by autologous split-thickness scalp transplantation. The skin condition of inserted place, expansion time, and total amount of normal saline injection of expanders, complications of skin and soft tissue expansion surgery, and survival of flap after the second stage surgery were observed and recorded. The long-term face and neck reconstruction effect and recovery of flap donor area were followed up. At the last follow-up, the 5-level Likert scale was used to evaluate the efficacy satisfaction of patients. Results: Of the 34 expander inserted places in 17 patients, 22 places were superficial scar skin after deep partial-thickness burns, 8 places were superficial scar skin after multiple skin donations, and 4 places were normal skin. After 4 to 15 months of expansion, the total normal saline injection volume was 238 to 2 000 mL, with no complications occurred. After the second stage surgery, the distal part of 2 pedicled flaps was partially necrotic, and the necrotic wounds were healed after flap dressing and free transplantation of contralateral expanded triangular flaps, respectively; the other flaps survived completely. During 6 to 18 months of follow-up, except for 2 expanded paraumbilical flaps and 1 expanded groin flap, which were bloated and improved by flap thinning, the appearance and texture of the other flaps were good, and all the flap donor sites recovered well. At the last follow-up, the face and neck scar contracture deformities were significantly improved in all patients, and the satisfaction of curative effect of patient was very satisfactory in 8 patients and relatively satisfactory in 9 patients. Conclusions: The expanded flaps of chest, abdomen, and other parts, combined with local advance, pedicled, and free transplantation, can effectively reconstruct scar contracture deformities in the face and neck after extensive burns, restore the function of operative area and improve the appearance simultaneously, with high degree of patient satisfaction, which is worthy of promotion in clinic.

Lactobacillus gasseri CKCC1913 mediated modulation of the gut-liver axis alleviated insulin resistance and liver damage induced by type 2 diabetes

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by dysregulation of lipid metabolism, insulin resistance, and gut microbiota disorder. Compared to drug interventions, probiotic interventions may have a more enduring effect without producing any side effects. Thus, the potential of probiotics as a therapeutic approach for diabetes and other metabolic disorders has gained increasing attention in recent years. In this study, we evaluated the therapeutic efficacy of Lactobacillus gasseri CKCC1913, a potential probiotic strain, in high-fat diet-induced insulin-resistant diabetes using the C57BL/6J mouse animal model. From the results, L. gasseri CKCC1913 has been shown to increase glucose tolerance, reduce fasting blood glucose levels in diabetic mice, and reduce the expression of pro-inflammatory cytokines, such as TNF-α and IL-6. Besides, L. gasseri CKCC1913 intervention effectively alleviated oxidative stress damage by increasing SOD activity, decreasing MDA levels, reducing insulin resistance, and improving dyslipidemia caused by diabetes. The potential mechanism of L. gasseri CKCC1913 in improving metabolic health and alleviating diabetes involves an increased abundance of beneficial bacteria, such as Parabacteroides merdae, which directly produce short-chain fatty acids that help regulate immune cells and reduce inflammation. SCFAs also enter the bloodstream and promote antioxidant enzyme activity in the liver, protecting against oxidative damage. Additionally, L. gasseri CKCC1913 influences local bacterial metabolism pathways, such as the superpathway of unsaturated fatty acid biosynthesis, leading to an increase in unsaturated fatty acids, increasing high-density lipoprotein cholesterol (HDL-C) levels and improving lipid metabolism and glucose control in diabetic mice. In summary, in this study, L. gasseri CKCC1913 and its potential impact on metabolic health highlight the promising potential of probiotics as a therapeutic approach for diabetes. Future research should focus on identifying the optimal dose and duration, investigating the long-term effects and mechanisms of action, and exploring the potential use of probiotics as an adjunct to other therapies or in preventing metabolic disorders.

Vitamin C inhibits the growth of colorectal cancer cell HCT116 and reverses the glucose-induced oncogenic effect by downregulating the Warburg effect

Malnutrition caused by insufficient nutritional supply may significantly hinder the quality of life among cancer patients. Sugar provides energy and nutritional support, but it also promotes cancer growth. Warburg effect is the reprogrammed glucose metabolic mode of cancer cells that meets the intensified ATP demand and biosynthesis. Vitamin C (VC) has anti-tumor effect. However, the relationship between cytotoxicity of VC on cancer cells and Warburg effect remains elusive, the effect of VC on glucose-induced oncogenic effect is also unclear. Based on colorectal cancer cell HCT116, our finding revealed that the discrepant oncogenic effect of different sugar is closely related to the intensification of Warburg effect, with glucose being the potent oncogenic component. Notably, as a potential Warburg effect inhibitor, VC suppressed cancer growth in a concentration-dependent manner and further reversed the glucose-induced oncogenic effect. Furthermore, VC protected tumor-bearing mice from insulin sensitivity impairment and inflammatory imbalance. These findings imply that VC might be a useful adjuvant treatment for cancer patients seeking to optimize nutritional support.

Influence of off-hours admission on outcomes of ischemic stroke: a systematic review and meta-analysis of contemporary studies

OBJECTIVE

The aim of this study was to document pooled evidence on the association between admission during off-hours and/or weekends and the risk of mortality and poor functional outcome in patients with ischemic stroke, as compared to admission during regular working hours and/or weekdays.

MATERIALS AND METHODS

We conducted a systematic search using PubMed, EMBASE, and Scopus databases. Observational studies published between 2013 and 2023 that investigated the association between weekend/off-hours admission and outcomes (mortality and functional outcomes) of ischemic stroke were considered for inclusion. A random effects model was used to conduct the analysis, and effect sizes were reported as pooled odds ratio (OR) or hazards ratio (HR) with corresponding 95% confidence intervals.

RESULTS

The analysis consisted of 31 studies and found that patients admitted during weekend/off-hours had a higher risk of in-hospital (OR 1.12, 95% CI: 1.06, 1.18), and 1-month post-admittance mortality (OR 1.13, 95% CI: 1.06, 1.20). However, the risk of mortality after 3, 6, and 12 months was not statistically different between the two patient groups. Patients admitted during weekends/off-hours had a slightly higher risk of poor functional outcomes (modified Rankin Scale score of ≥3) at 1-month post-admittance (OR 1.06, 95% CI: 1.00, 1.11). However, after 3, 6, and 12 months, the risk of poor functional outcomes was similar in both patient groups. Egger's test did not suggest the presence of publication bias for any of the outcomes.

CONCLUSIONS

Individuals who suffer from ischemic stroke and present outside of regular working hours or on weekends have a higher likelihood of experiencing short-term mortality and unfavorable functional outcomes.

[Comparison of long-term clinical outcomes between transvaginal mesh and pelvic floor reconstruction with native tissue repair in the treatment of advanced pelvic organ prolapse]

Objective: To study the long-term clinical effect of transvaginal mesh (TVM) and pelvic floor reconstruction with native tissue repair (NTR) in the treatment of advanced pelvic organ prolapse (POP). Methods: Totally 207 patients with advanced POP who were treated in Hunan Provincial Maternal and Child Health Care Hospital from Jan. 2016 to Sep. 2019 were enrolled. The patient's pelvic organ prolapse quantification were all at degree Ⅲ or above, and they all complained for different degree of symptoms. They were divided into two groups according to the different surgical methods, TVM group and NTR group. In TVM group, the mesh was implanted through the vagina for pelvic floor reconstruction, while in NTR group, the traditional transvaginal hysterectomy combined with uterosacral ligament suspension and anterior and posterior wall repair, as well as perineal body repair were performed. The median follow-up time was 60 months, during the follow up time, 164 cases (79.2%, 164/207) had completed follow-up, including 76 cases in TVM group and 88 cases in NTR group. The perioperative data and complication rates of the two groups were compared, and the subjective and objective outcomes of the two groups at 1, 3 and 5 years were observed, respectively. The objective efficacy was evaluated by three composite criteria, namely: (1) the distance from the farthest end of the prolapse of the anterior and posterior wall of the vagina to the hymen is ≤0 cm, and the descending distance of the top is ≤1/2 of the total length of the vagina; (2) determine the disappearance of relevant POP symptoms according to "Do you often see or feel vaginal mass prolapse？"; (3) no further operation or pessary treatment was performed due to prolapse. If the above three criteria were met at the same time, the operation is successful; otherwise, it was recurrence. The subjective efficacy was evaluated by the pelvic floor distress inventory-short form 20 (PFDI-20) and pelvic floor impact questionnaire-short form 7 (PFIQ-7). Results: The median follow-up time of the two groups was 60 months (range: 41-82 months). Five years after the operation, the subjective and objective cure rates of TVM group were 89.5% (68/76) and 94.7% (72/76), respectively. The subjective and objective cure rates in NTR group were 80.7% (71/88) and 85.2% (75/88), respectively. There were significant differences in the subjective and objective cure rates between the two groups (χ2=9.869, P=0.002; χ2=3.969, P=0.046). The recurrence rate of TVM group was 5.3% (4/76), and that of NTR group was 14.8% (13/88). There was a significant difference between the two groups (P=0.046). The postoperative PFDI-20 and PFIQ-7 scores of the two groups were significantly lower than those before surgery, and there were significant differences of the two groups before and after surgery (all P<0.05). Postoperative mesh exposure in TVM group was 1.3% (1/76). Conclusions: The long-term outcomes between the two groups show that the subjective and objective outcomes of pelvic floor reconstruction in TVM group are significantly higher than those in NTR group, and the recurrence rate is significantly lower than that in NTR group. TVM has certain advantages in the treatment of advanced POP.

[Treatment methods of upper limbs with destructive electric burns and its clinical efficacy]

Objective: To investigate the treatment methods of upper limbs with destructive electric burns and its clinical efficacy. Methods: A retrospective observational study was conducted. From July 2014 to December 2020, 20 male patients with destructive electric burns in upper limbs who met the inclusion criteria were admitted to Tongren Hospital of Wuhan University & Wuhan Third Hospital, aged from 21 to 57 years, of whom 7 patients underwent emergency surgery, and a total of 20 affected limbs were treated with limb salvage. The necrotic bone was resected in 5 affected limbs, the residual hand and wrist at the distal end of left affected limb was replanted to the residual end of the right forearm in one patient in a cross heterotopic way, and short reduction and replantation after osteotomy were performed for two affected limbs with distal ulnar and radial necrosis. After thorough debridement, the area of wound proposed to be repaired by tissue flap was from 12 cm×7 cm to 58 cm×13 cm. According to the size and distribution of wound, the wounds of 2 affected limbs were repaired by transplantation of pedicled latissimus dorsi myocutaneous flap and free groin flap with vascular anastomosis. The wounds of the remaining 17 affected limbs were repaired with the transplantation of free latissimus dorsi myocutaneous flap, anterolateral thigh flaps, and paraumbilical perforator flap, with 10 affected limbs with larger wounds being jointly transplanted with the groin flap or the paraumbilical perforator flap on the other side. The total grafted tissue flap area was 20 cm×8 cm to 52 cm×20 cm. During tissue flap transplantation, according to the length of blood vessel defect in the affected limb, the distal artery of the affected limb was bridged with the distal part of flap vascular pedicle, undamaged vein on the affected side, superficial vein of abdominal wall, and great saphenous vein, etc., in 14 affected limbs, and the great saphenous vein was grafted in 3 of them with impeded distal return for recanalization of distal limb veins. The wound in the donor area was repaired by direct suture or grafting with split-thickness scalp. After the wound was basically healed, the functional rehabilitation training was started gradually, and the functional reconstruction and scar rectification surgery were started 3 months after tissue flap transplantation. The survival of tissue flaps/skin grafts, wound healing, limb salvage, and follow-up status after surgery were recorded. At the last follow-up, the function of the successfully salvaged limb was evaluated and scored by the disabilities of the arm, shoulder and hand (DASH) scoring scale. Results: After surgery, the grafted tissue flap in the affected limb and the skin grafts transplanted on the wound at flap donor site survived, and wounds at the recipient and donor sites healed well. Two affected limbs had distal necrosis within 10 days after tissue flap transplantation, and the middle and upper forearms were amputated. The remaining 18 affected limbs were successfully salvaged (including shortened replantation and cross heterotopic replantation). During 6-48 months of follow-up, 5 affected limbs that were successfully salvaged developed aseptic dissolution of residual tendon and bone tissue 3 to 18 months after tissue flap transplantation, which gradually healed after surgical debridement combined with vacuum sealing drainage treatment. At the last follow-up, the stump of two affected limbs healed well after amputation; 18 affected limbs that were successfully salvaged all survived well, of which 8 affected limbs had good recovery of finger flexion and extension function and thumb opponensplasty and could complete daily activities independently, 9 affected limbs regained partial mobility and could complete daily activities such as dressing and eating with the assistance of the opposite upper limb or auxiliary devices, and one affected limb had no function. At the last follow-up, the functional scores of DASH scoring scale of the 18 affected limbs that were successfully salvaged ranged from 30.0 to 100. Conclusions: Timely surgical debridement, proper treatment of the injured bone tissue, effective vascular bridging for reconstruction of the distal artery of the affected limb, and the use of blood-rich tissue flap to repair the wound, combined with early rehabilitation and functional restoration treatment, are beneficial to salvage the upper limb with destructive electric burns and improve the function of the affected limb.

[Effect of the nomenclature of non-alcoholic fatty liver disease on diagnosis and treatment of fatty liver disease concomitant with other liver diseases]

Fatty liver disease (FLD) is one of the major causes of chronic liver disease worldwide. With the increasing incidence of obesity and metabolic syndrome worldwide, FLD concomitant with other liver diseases is becoming more common, and multiple etiological overlap is associated with poor disease prognosis. Therefore, FLD concomitant with other liver diseases is a clinical concerning issue. Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of disease continuum from non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH), and relative end stage liver disease, excluding other factors that may lead to fatty liver disease such as excessive alcohol consumption et. al. Following the nomenclature of NAFLD with metabolic associated fatty liver disease (MAFLD), an international panel of experts proposed a new name in June 2023 as Metabolic dysfunction - associated steatotic liver disease (MASLD), replacing the word "fatty" with "steatotic," The effect of lipid toxicity on FLD progression was highlighted. Compared with the concept of MAFLD, the disease spectrum of MASLD is broader, and the etiology and mechanism are more clear. The nomenclature of FLD brings some influence to the diagnosis and treatment of chronic liver diseases concomitant with FLD, including chronic hepatitis B, alcoholic fatty liver disease and genetic metabolic diseases. This article reviews the influence of renaming FLD on the diagnosis and treatment of FLD concomitant with other etiologies caused liver diseases.

[A case with giant ulcer caused by skin diffuse large B-cell lymphoma in the axilla]

In May 16th, 2019, a male patient (aged 51 years) with a rare giant ulcer caused by skin diffuse large B-cell lymphoma in the axilla was admitted to Tongren Hospital of Wuhan University & Wuhan Third Hospital, and the ulcer wound was confirmed by biopsy and immunohistochemical analysis after extensive excision. Ultimately, a good prognosis was obtained by transplantation of flap and skin graft in combination with radiotherapy and chemotherapy.

Numerical simulation and testing of laser-MIG hybrid-welding angle-structure sheets

Numerical simulation and experimental investigation of laser-MIG hybrid angle-welding low-carbon 1.5-mm-thin SPCC steel sheets are presented in this work. The transient simulation analysis provides an access to the thermal-fluid phenomena prediction by employing a hybrid three-dimensional heat source model. Special attention is paid to the melt dynamic behaviors within the triangular molten pool affected by the Marangoni convection. The simulation results show that the temperature and its gradient distribution are symmetrical with respect to the laser beam, which is validated well by the experimental study. The microstructure of the welded joints was analyzed by scanning electron microscopy and transmission electron microscopy. The results show that the cross-section microstructures of welded joint are mainly composed of the weld zone, narrow heat-affected zone, and substrate. The semielliptic-like molten pool shape is consistent with that of the simulated results. The finer microstructure in the weld bead results from the rapid cooling rate of laser welding confirmed by the FEM calculation. The columnar and equiaxed dendrites are formed in the peripheral and central region of the molten pool, which is beneficial for the improvement of the microhardness.

[Analysis of factors associated with futile recanalization after endovascular treatment for acute ischemic stroke with large vessels occlusion in anterior intracranial circulation]

Objective: To analyze the related factors of futile recanalization (FR) after emergency endovascular treatment of large artery occlusion in anterior circulation. Methods: Three studies on endovascular treatment of acute anterior circulation large vessels occlusion stroke were selected, and their data were merged for retrospective analysis. Patients were divided into the FR group and favorable prognosis group according to the functional prognosis. Risk factor analysis was conducted using multivariate logistic regression. Results: A total of 1 581 patients were finally included, with 858 (48.9%) patients in favorable prognosis group and 926 (51.91%) patients in FR group. Among them, there were 939 males and 642 females, with a mean age of (65±12) years. Multivariate logistic regression analysis showed that National Institute of Health Stroke Scale (NIHSS) score (OR=1.089,95%CI:1.066-1.113), puncture to recanalization time (OR=0.756, 95%CI:0.586-0.971), age (OR=1.04,95%CI:1.029-1.051), serum glucose (OR=1.101,95%CI:1.062-1.143), systolic blood pressure (OR=1.005,95%CI:1.001-1.010), passes≥3(OR=1.941,95%CI:1.294-2.941)Alberta stroke program early CT (ASPECT) score (OR=0.919,95%CI:0.847-0.996), occlusion site (M1 segment of middle cerebral artery, OR=0.744,95%CI:0.565-0.980) and collateral circulation [(2 points, OR=0.757, 95%CI:0.581-0.985); (3-4 points, adjusted OR=0.640, 95%CI: 0.472-0.866)] were independent factors of FR. Conclusion: The incidence of FR in patients with large artery occlusion in anterior circulation who achieve satisfied reperfusion after endovascular treatment is high. Higher NIHSS score, longer puncture to recanalization time, older age, higher serum glucose and systolic blood pressure are risk factors, while lower ASPECTS, occlusion in cerebral middle M1 segment, better collateral circulation are protective factors.