Objective:To investigate the application of the conjugate gradient (CG) algorithm to treatment plan optimization for intensity-modulated brachytherapy (IMBT).Methods:The general Monte Carlo software TOPAS was utilized to simulate the 192Ir source of IMBT, and the unit dose contribution matrix was calculated. An objective function was established using the weighted least squares method and was solved using the CG algorithm to achieve optimized IMBT treatment plans. The optimization was validated using five clinical cervical cancer cases under modulation width 60°. The dose distributions of IMBT treatment plans under 45°, 60°, 90°, 120°, and 180° modulation widths were compared using the Wilcoxon test to determine the optimal IMBT treatment plan for cervical cancer treatment. Results:The CG algorithm successfully optimized IMBT treatment plans under modulation width 60° for five cases within 22.2 s on average. On the premise of sufficient target dose coverage, the average D2 cm 3 values of the bladder and rectum in IMBT treatment plans were 3.66 and 1.97 Gy, respectively, representing reductions of 0.54 and 0.69 Gy compared to traditional brachytherapy plans. For the five modulation widths, the D90% values of all IMBT treatment plans reached 6 Gy, without statistically significant differences ( P > 0.05). The average D2 cm 3 values of the bladder in IMBT treatment plans were significantly lower than those in the traditional brachytherapy plans( P<0.05), with modulation width 60° associated with the greatest reduction of 0.61 Gy. In contrast, the average D2 cm 3 values of the rectum under 45°, 60°, and 90° modulation widths decreased by 0.63, 0.54, and 0.45 Gy, respectively, compared to traditional plans, with statistically significant differences( P<0.05). Conclusions:The CG method enables rapid achievement of optimized IMBT treatment plans that meet clinical requirements, and modulation width 60° contributes to valid dosimetric optimization. This study can serve as a guide for the clinical implementation of IMBT.

Objective:To investigate the application of the conjugate gradient (CG) algorithm to treatment plan optimization for intensity-modulated brachytherapy (IMBT).Methods:The general Monte Carlo software TOPAS was utilized to simulate the 192Ir source of IMBT, and the unit dose contribution matrix was calculated. An objective function was established using the weighted least squares method and was solved using the CG algorithm to achieve optimized IMBT treatment plans. The optimization was validated using five clinical cervical cancer cases under modulation width 60°. The dose distributions of IMBT treatment plans under 45°, 60°, 90°, 120°, and 180° modulation widths were compared using the Wilcoxon test to determine the optimal IMBT treatment plan for cervical cancer treatment. Results:The CG algorithm successfully optimized IMBT treatment plans under modulation width 60° for five cases within 22.2 s on average. On the premise of sufficient target dose coverage, the average D2 cm 3 values of the bladder and rectum in IMBT treatment plans were 3.66 and 1.97 Gy, respectively, representing reductions of 0.54 and 0.69 Gy compared to traditional brachytherapy plans. For the five modulation widths, the D90% values of all IMBT treatment plans reached 6 Gy, without statistically significant differences ( P > 0.05). The average D2 cm 3 values of the bladder in IMBT treatment plans were significantly lower than those in the traditional brachytherapy plans( P<0.05), with modulation width 60° associated with the greatest reduction of 0.61 Gy. In contrast, the average D2 cm 3 values of the rectum under 45°, 60°, and 90° modulation widths decreased by 0.63, 0.54, and 0.45 Gy, respectively, compared to traditional plans, with statistically significant differences( P<0.05). Conclusions:The CG method enables rapid achievement of optimized IMBT treatment plans that meet clinical requirements, and modulation width 60° contributes to valid dosimetric optimization. This study can serve as a guide for the clinical implementation of IMBT.

Objective To investigate the safety and efficacy of sodium fluorescein-guided microsurgery in children with medulloblastoma,and to analyze the surgical efficacy and prognosis.Among them,12 cases underwent unilateral telovelar approach,2 cases underwent bilateral telovelar approach,and 6 cases underwent telovelar approach combined with transvermian approach.The intraoperative dose of sodium fluorescein was 2 mg/kg.Methods The clinical data of 20 patients with medulloblastoma treated with fluorescein sodium assisted microsurgery from January 2018 to August 2023 in Xinjiang Autonomous Region People's Hospital were retrospectively analyzed.Results Of the 20 patients,12 were male and 8 were female.The mean age of onset was(7.9±3.7)years.In all cases,there was clear tumor fluorescence,none of the cases had adverse reaction associated with the use of sodium fluorescein.There were 16 cases of gross-total resection,3 cases of near-total resection,1 case of partial resection,1 case of intracranial infection,2 case of subcutaneous effusion,2 cases of cerebellar mutism.The follow-up time was from 3 to 72 months.5 cases did not receive sufficient radiotherapy and chemotherapy,and 9 cases died due to tumor progression or recurrence.In all cases,the longest overall survival was 72 months,the mean survival time was 39.2 months,and the median survival time was 41.2 months.Conclusion Fluorescein sodium assisted microsurgery is safe and effective in pediatric medulloblastoma surgery.

Objective To develop a GPU-based Monte Carlo dose calculation module for helical tomotherapy(TOMO),and integrate it into the commercial software ArcherQA to achieve fast and accurate dose verification in clinic.Methods The TOMO treatment head was modeled using TOPAS to obtain phase space files,and a fast weight tuning algorithm was used to simulate particle transport in multi-leaf collimator for improving computational efficiency,and finally,GPU-based Monte Carlo algorithms in ArcherQA were used to simulate particle transport in patients.To verify the model accuracy,the ArcherQA calculated results in water tank were compared with measured data for different open fields.In addition,multiple comparisons among ArcherQA results,TPS results and ArcCHECK results were conducted on 15 clinical cases(5 cases in the head and neck,5 cases in the chest and abdomen,and 5 cases in the whole body).Results In the water tank tests for 40 cm×5.0 cm,40 cm×2.5 cm and 40 cm× 1.0 cm radiation fields,the average global relative errors of the percentage depth dose,transverse dose distribution,and longitudinal dose distribution calculated by ArcherQA with the corresponding measured values were 0.72％,0.66％,and 0.54％,respectively.Over 98％of the voxels had a global relative error of less than 1％.As for 15 clinical cases,in 2％/2 mm criteria,the mean Gamma passing rate was 98.1％between ArcherQA and TPS,99.1％between TPS and ArcCHECK,and 99.4％between ArcherQA and ArcCHECK.The uncertainty of the simulation maintained less than 1％,and the average time taken for calculation based on patient CT vs ArcCHECK phantom was 87 s vs 64 s.Conclusion ArcherQA can be used for independent dose validation for TOMO plans for it can provide fast and accurate dose calculations.

Uncommon epidermal growth factor receptor (EGFR) mutations account for 10%-20% of all EGFR mutations in non-small-cell lung cancer (NSCLC). The uncommon EGFR-mutated NSCLC is associated with poor clinical outcomes and generally achieved unsatisfactory effects to the current therapies using standard EGFR-tyrosine kinase inhibitors (TKIs), including afatinib and osimertinib. Therefore, it is necessary to develop more novel EGFR-TKIs to treat uncommon EGFR-mutated NSCLC. Aumolertinib is a third-generation EGFR-TKI approved in China for treating advanced NSCLC with common EGFR mutations. However, it remains unclear whether aumolertinib is effective in uncommon EGFR-mutated NSCLC. In this work, the in vitro anticancer activity of aumolertinib was investigated in engineered Ba/F3 cells and patient-derived cells bearing diverse uncommon EGFR mutations. Aumolertinib was shown to be more potent in inhibiting the viability of various uncommon EGFR-mutated cell lines than those with wild-type EGFR. And in vivo, aumolertinib could also significantly inhibit tumor growth in two mouse allograft models (V769-D770insASV and L861Q mutations) and a patient-derived xenografts model (H773-V774insNPH mutation). Importantly, aumolertinib exerts responses against tumors in advanced NSCLC patients with uncommon EGFR mutations. These results suggest that aumolertinib has the potential as a promising therapeutic candidate for the treatment of uncommon EGFR-mutated NSCLC.

Objective:To investigate the value of the 8-channel eye surface phased array coil in improving image quality and demonstrating ocular masses on 3.0 T MR scanner.Methods:From July 2018 to January 2020, the data of orbital MRI in 692 patients with ocular masses on 6 medical centers were prospectively collected. The patients were simple randomly assigned into 8-channel eye surface phased array coil group (413 patients) or 8-channel head phased array coil group (279 patients), with the same MRI sequences. The signal to noise ratio (SNR) and contrast to noise ratio (CNR) were calculated in orbital anatomy structures and masses (eyelid mass, intraocular mass, lacrimal mass and orbital mass). The image quality scores including motion artifact, mass margin, the relationship between the mass and adjacent structures, and overall image quality were recorded. The differences of image quality between the two groups were compared by two independent sample t-test or Wilcoxon rank test. Results:The SNR and CNR were higher in eye surface coil group than those in head coil group ( P<0.05). The scores of ocular movement artifacts were higher in head coil group than those in surface coil group ( P<0.05). The scores of intraocular mass margin, the relationship between the mass and adjacent structures, and overall image quality were higher in surface coil group than those in head coil group ( P<0.001). There were no significant differences in mass margin, the relationship between the mass and adjacent structures, and overall image quality scores of eyelid, lacrimal gland, and orbital mass between the two groups ( P>0.05). Conclusion:3.0 T MR scanner combined with the 8-channel eye surface phased array coil can improve the SNR and CNR of orbital MR images, the demonstration of the intraocular mass margin and the relationship between the mass and adjacent structures.

Objective:To investigate the value of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) in improving ability of demonstrating ocular masses on 3.0 T MR scanner.Methods:This study was a multi-center prospective study involving 6 centers. From July 2018 to January 2020, totally 413 patients with ocular masses from 6 centers were prospectively enrolled, and all of them underwent T 1WI and T 2WI, PROPELLER T 1 FLAIR and T 2WI, and contrast-enhanced scans. The signal intensity of eyelid, vitreous body, lacrimal gland, intraorbital segment of optic nerve, and orbital masses of eyelid, intraocular, lacrimal gland and retrobulbar were measured by two radiologists, and the signal to noise ratio (SNR) and contrast noise ratio (CNR) were calculated. The 5-point scoring method was used to evaluate the motion artefacts, tumor edges and the relationship between the tumor and adjacent structures, and the overall score of image quality was calculated. Paired t-test or Wilcoxon signed rank test was used to compare the image quality between PROPELLER and non-PROPELLER images. Results:The SNR and CNR of PROPELLER T 2WI were higher than those of non-PROPELLER T 2WI (all P<0.001). The SNR and CNR of PROPELLER T 1 FLAIR were lower than those of non-PROPELLER T 1WI (all P<0.05). The scores of artefacts and overall image quality in PROPELLER images were higher than those in non-PROPELLER images (all P<0.001). The tumor edge and the relationship between the tumor and adjacent structures scores of eyelid, intraocular, and lacrimal gland masses in PROPELLER images were higher than those in non-PROPELLER images (all P<0.001),while compared to non-PROPELLER images, retro-global masses in PROPELLER images showed no significant differences (all P>0.05). Conclusion:PROPELLER can reduce ocular motion artefacts, effectively improve image quality and ability of demonstrating anterior (eyelid, intraocular, and lacrimal gland) masses.

Objective To investigate the imaging features of inflammatory bowel disease.Methods Totally 41 cases of inflammatory bowel disease were selected,including 28 cases of ulcerative colitis and 13 cases of Crohn's disease.The X-ray,CT,magnetic resonance (MRI) and other imaging findings of ulcerative colitis and Crohn's disease were compared.Results There were certain differences in X-ray,CT,MRI and other imaging findings of ulcerative colitis and Crohn's disease,which should be carefully identified.Conclusion Any examination has its advantages and limitations in the diagnosis of inflammatory bowel disease.It should be closely combined with clinical and other laboratory tests.

Objective To investigate the imaging features of inflammatory bowel disease.Methods Totally 41 cases of inflammatory bowel disease were selected,including 28 cases of ulcerative colitis and 13 cases of Crohn's disease.The X-ray,CT,magnetic resonance (MRI) and other imaging findings of ulcerative colitis and Crohn's disease were compared.Results There were certain differences in X-ray,CT,MRI and other imaging findings of ulcerative colitis and Crohn's disease,which should be carefully identified.Conclusion Any examination has its advantages and limitations in the diagnosis of inflammatory bowel disease.It should be closely combined with clinical and other laboratory tests.

BACKGROUND: Thoracolumbar fracture is most common seen in spinal fractures. The paraspinal muscle is subjected to extensive detachment and traction in traditional posterior approach, so the muscular ischemia and denervation lead to muscle atrophy further inducing intractable low back pain. Thereafter, minimally invasive spinal surgery becomes more and more popular.OBJECTIVE: To investigate the clinical efficacy of pedicle screw fixation through Wiltse approach combined with injectable calcium sulfate bone cement for single-level thoracolumbar fracture.METHODS: Clinical data of 52 patients with single-level thoracolumbar fracture without nerve injury were analyzed retrospectively, and were then assigned to observation (n=28) and control groups (n=24) according to the treatment method. The patients in the observation group were treated with pedicle screw fixation through Wiltse approach plus implanted with injectable calcium sulfate bone cement, and those in the control group were subjected to pedicle screw fixation through posterior approach plus implanted with injectable calcium sulfate bone cement. The operation time, blood loss and hospitalization time were compared between two groups. The low back pain was observed at baseline, 1 week and 3 months postoperatively, and the percentage of anterior vertebral height revealed on X-ray was observed at baseline, before ambulation, and during last follow-up. Moreover, the complications, loosening and rupture of the screws were recorded.RESULTS AND CONCLUSION: (1) All patients were followed up, and the follow-up time was 16-24 months. (2) The operation time, blood loss and hospitalization time in the observation group were significantly less than those in the control group (P < 0.05). (3) The postoperative visual analogue scale scores in the two groups were significantly lower than those before surgery, and the scores showed significant differences between two groups (P < 0.05). (4) The percentage of anterior vertebral height before ambulation and during last follow-up in the two groups was significantly improved, and the percentage showed significant difference between two groups at each time point (P < 0.05). (5) These findings suggest that based on strict indications, the pedicle screw fixation through Wiltse approach combined with injectable calcium sulfate bone cement is safe for single-level thoracolumbar fracture, which restores the anterior vertebral height rapidly, alleviates pain and exhibits satisfactory long-term efficacy. Furthermore, it holds shorter operation time and less blood loss than the traditional approach.