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Novel Wavelet-Based Segmentation of Prostate CBCT Images with Implanted Calypso Transponders

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International Journal of Medical physics, clinical Engineering and Radiation oncology 2017年第3期6卷 336-343页

作者： Yingxia Liu Ziad Saleh Yulin Song Maria Chan Xiang Li Chengyu Shi Xin Qian Xiaoli Tang Shandong Communication and Media College Jinan China Medical physics department Memorial Sloan Kettering Cancer Center New York NY USA Radiation oncology North Shore Long Island Jewish Health System New Hyde Park NY USA

Segmentation of prostate Cone Beam CT (CBCT) images is an essential step towards real-time adaptive radiotherapy (ART). It is challenging for Calypso patients, as more artifacts generated by the beacon transponders are present on the images. We herein propose a novel wavelet-based segmentation algorithm for rectum, bladder, and prostate of CBCT images with implanted Calypso transponders. For a given CBCT, a Moving Window-Based Double Haar (MWDH) transformation is applied first to obtain the wavelet coefficients. Based on a user defined point in the object of interest, a cluster algorithm based adaptive thresholding is applied to the low frequency components of the wavelet coefficients, and a Lee filter theory based adaptive thresholding is applied on the high frequency components. For the next step, the wavelet reconstruction is applied to the thresholded wavelet coefficients. A binary (segmented) image of the object of interest is therefore obtained. 5 hypofractionated Calypso prostate patients with daily CBCT were studied. DICE, Sensitivity, Inclusiveness and ΔV were used to evaluate the segmentation result.

关键词： CBCT Prostate Segmentation Wavelets MWDH

Intraoperative Open-Cavity Implant for Accelerated Partial Breast Irradiation Using High-Dose Rate Multicatheter Brachytherapy in Japanese Breast Cancer Patients: A Single-Institution Registry Study

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Journal of Cancer Therapy 2012年第5期3卷 822-830页

作者： Kazuhiko Sato Yoshio Mizuno Masahiro Kato Takahiro Shimo Jun Kubota Naoko Takeda Yuko Inoue Hiroshi Seto Tomohiko Okawa department of Breast oncology Tokyo-West Tokushukai Hospital Tokyo Japan department of Radiation oncology Tokyo-West Tokushukai Hospital Tokyo Japan Health Evaluation Center Utsunomiya Memorial Hospital Tochigi Japan Inoue Ladies Clinic Tokyo Japan Seto Hospital Saitama Japan

Background: Previous research has compared the efficacies of accelerated partial breast irradiation (APBI) and wholebreast irradiation (WBI). APBI immediately after surgery may provide more benefit after intraoperative insertion of catheters. Although balloon catheter-based APBI is available in the US, it is difficult in Japanese women, who have relatively small breasts. With the applicators being implanted during tumor removal, APBI can be started immediately after surgery. The aim of this study was to assess the safety and efficacy of APBI using the intraoperative open-cavity implant technique. Method: Patients (age≥40 years) with invasive breast cancer (diameter≤3 cm) were enrolled. Before lumpectomy, the insertion of applicators and delivery doses were simulated by computed tomography (CT). After confirmation of free margins and negative sentinel nodes (SNs) using frozen section analysis, applicators were inserted. Postoperative CT-based dose distribution analysis was performed using dose-volume histograms. APBI was started on the day of surgery, delivering 32 Gy in 8 fractions over the following 5-6 days, and it covered a distance of 2 cm from tumor margins. This observational study was approved by the institutional review board of our hospital. Results: From October 2008 to July 2012, 157 women (160 lesions) were enrolled (age 55.0 years, radiotherapy-related toxicities were mild. However, 12 patients (7.5%) experienced wound breakdown because of surgical site infection. Two patients developed ipsilateral breast tumor recurrence (1 marginal, 1 at a distant site). Conclusions: Despite the small number of participants and a short follow-up period, our results suggest that this technique could be helpful in establishing clinical safety and efficacy.

关键词： Breast Cancer Partial Breast Irradiation Multicatheter Brachytherapy

Computational and Experimental Approaches for Evaluating Dose under a Block in TBI Geometry

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International Journal of Medical physics, clinical Engineering and Radiation oncology 2022年第1期11卷 77-83页

作者： Laura Russell Jussi Sillanpaa department of Medical physics Memorial Sloan-Kettering Cancer Center New York USA

Total Body Irradiation (TBI) patients are often treated at extended distances of several meters, with blocking made from high-Z materials placed close to the patients’ skin. Evaluating the dose under a block (e.g., for implanted medical device shielding purposes) in such a geometry is challenging. We compare the performance of two commonly used dose calculation algorithms, Anisotropic Analytical Algorithm (AAA) and Acuros XB, with Optically Stimulated Lumine- scence (OSLD) and ion chamber measurements in phantoms. The calculations and phantom measurements are also compared with in-vivo OSLD measure- ments. We find that OSLD and ion chamber measurements in phantom are good predictors of in-vivo measurements, while both AAA and Acuros XB sys- tematically overestimate the block transmission. We found Acuros XB to be accurate enough for a rough upper estimate (dose under block overestimated by 7% - 22%), while for AAA the overestimate was more severe (90% - 110%);the reason is that AAA does not account for the increase in pair production cro- ss-section in high-Z materials.

关键词： Total Body Irradiation AAA Acuros XB ICD Dose under Block

A Case for “Radiolysis” in radiotherapy of Keloids

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International Journal of Medical physics, clinical Engineering and Radiation oncology 2014年第4期3卷 226-234页

作者： K. Malaker H. Weatherburn H. De Souza department of clinical Medicine Ross University School of Medicine Portsmouth Dominica Cancer Centre of London London UK

Successful treatment of keloids has eluded the medical community since their first description. Multitudes of therapeutic options are available, but none achieves satisfactory resolution of keloids. One major stumbling block is lack of understanding about their genesis. Assuming keloids are tumors, attempts have been made to treat this condition with standard radiotherapy, with dismal results. Keloidal masses are not an active biological entity. They are aggregations of cellular, hypovascular, hypoxic bundles of collagen, which are produced by atypical fibroblasts in the wounds and eventually cease production due to a hostile biological environment. Having no demonstrable inherent process of disposal of these collagen bundles, this excessive collagen tends to linger to form the bulk of keloids. The lesions eventually become symptomatic and aesthetically unacceptable, and therapeutic intervention is sought. Of all available treatments, such as post-resection radiotherapy, primary radiotherapy in selected cases and primary brachytherapy stand out above any other form of treatment. Be it brachytherapy or external beam treatment, one fundamental aspect of radiation action is the process of “radiolysis”, explaining why “radiobiological” approaches have been ineffective.

关键词： Radiotheraphy Radiolysis Keloid Treatment

Differential regulation of JAK1 expression by ETS1 associated with predisposition to primary biliary cholangitis

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Journal of Genetics and Genomics 2023年第10期50卷 807-812页

作者： Peng Jiang Chan Wang Mingming Zhang Ye Tian Weifeng Zhao Junyi Xin Yexi Huang Zhibin Zhao Wenjuan Sun Jie Long Ruqi Tang Fang Qiu Xingjuan Shi Yi Zhao Li Zhu Na Dai Lei Liu Xudong Wu Jinshan Nie Bo Jiang Youlin Shao Yueqiu Gao Jianjiang Yu Zhigang Hu Zhidong Zang Yuhua Gong Yaping Dai Lan Wang Ningling Ding Ping Xu Sufang Chen Lu Wang Jing Xu Luyao Zhang Junyan Hong Ruonan Qian Hu Li Xuan Jiang Congwei Chen Wenyan Tian Jian Wu Yuzhang Jiang Chongxu Han Kui Zhang Hong Qiu Li Li Hong Fan Liming Chen Jianqiong Zhang Zhongsheng Sun Xiao Han Zhenhua Dai Erguang Li M.Eric Gershwin Zhexiong Lian Xiong Ma Michael F.Seldin Weichang Chen Meilin Wang Xiangdong Liu Key Laboratory of Developmental Genes and Human Diseases School of Life Science and TechnologySoutheast UniversityNanjingJiangsu 210096China Institute of Translational Medicine Yangzhou University Medical CollegeYangzhouJiangsu 225009China department of Radiology&oncology The Second Affiliated Hospital of Soochow UniversitySuzhouJiangsu 215004China The First Affiliated Hospital of Soochow University SuzhouJiangsu 215006China department of Bioinformatics School of Biomedical Engineering and InformaticsNanjing Medical UniversityNanjingJiangsu 210029China Author links open overlay panelYexi Huang Guangdong Provincial People's Hospital Guangdong Academy of Medical SciencesGuangzhouGuangdong 510080China department of Gastroenterology and Hepatology Shanghai Institute of Digestive DiseasesShanghai Jiao Tong University School of Medicine Affiliated Renji HospitalShanghai 200001China department of Laboratory Medicine The Fourth Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210031China department of Gastrointestinal Endoscopy Eastern Hepatobiliary Surgery HospitalShanghai 201800China The Fifth People's Hospital Soochow UniversitySuzhouJiangsu 215007China department of Gastroenterology Jiangsu University Affiliated Kunshan HospitalKunshanJiangsu 215300China department of Gastroenterology Yixing People's HospitalYixinJiangsu 214200China department of Gastroenterology Yancheng First People's HospitalYanchengJiangsu 224005China department of Gastroenterology Taicang First People's HospitalSoochow UniversityTaicangJiangsu 215400China department of Hepatology Jingjiang Second People's HospitalJingjiangJiangsu 214500China department of Hepatology The Third People's Hospital of ChangzhouChangzhouJiangsu 213001China department of Liver Diseases Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 201203China department of Laboratory Medicine Jiangyin People's HospitalSoutheast UniversityJiangyinJiangsu 214400China department of Labora

Primary biliary cholangitis(PBC)is an autoimmune liver disease characterized by the destruction of intrahepatic small bile ducts and progressive cholestasis,eventually leading to liver cirrhosis and hepatic failure wi... 详细信息

关键词： cholangitis biliary

Stereotactic radiotherapy Planning Using Modified Dynamic Conformal Arcs under Considering the Possibility for Amended Visual Organ Displacement Resulting from Early Tumor Shrinkage during Treatment for Perioptic Involvement of Myeloma

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International Journal of Medical physics, clinical Engineering and Radiation oncology 2014年第3期3卷 183-192页

作者： Kazuhiro Ohtakara Hiroaki Hoshi department of Radiation oncology Murakami Memorial Hospital Asahi University Gifu Japan Department of Radiology Gifu University Graduate School of Medicine Gifu Japan department of Radiology Gifu University Graduate School of Medicine Gifu Japan

Treatment planning of radiotherapy for skull base involvement of multiple myeloma presenting with visual impairment should be optimized to alleviate symptoms immediately and sufficiently while minimizing toxicities. Two such patients were treated with fractionated stereotactic radiotherapy by using Dynamic Conformal Arcs (DCA) under image guidance based on bony anatomy alignment. DCA planning was optimized after considering the possibility for amendment of visual organ displacement resulting from early tumor shrinkage during treatment through 1) the use of a target volume with modified geometry as a surrogate for leaf adaptation in order to improve target coverage, and 2) manual adjustment of a subset of leaf positions to reduce the dose gradient immediately inside the target boundary facing the visual organs and to eliminate an undesirable dose hotspot. In both cases, anticipated geometric changes in the target volume associated with improvement of visual organ displacement toward the target centroid were observed before the completion of treatment. Favorable visual functional outcomes as well as local tumor control were achieved during 14 months and 4 months follow-up periods. Notably, inexorable visual loss in one patient was fully reversed within one month after radiotherapy. We described the modification techniques for DCA planning in detail.

关键词： Multiple Myeloma Interfractional Anatomical Change Dynamic Conformal Arcs Image-Guided radiotherapy Stereotactic radiotherapy

The Journey of SRS: An Initial Experience of Starting Sterotactic Radiosurgery Facility at Purbanchal Cancer Hospital—First in Nepal

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International Journal of Medical physics, clinical Engineering and Radiation oncology 2023年第2期12卷 37-50页

作者： Birendra Kumar Yadav Karthik Nagamuthu Alok Thakur Kushal Rizal Umesh Kumar Sharma Ujwal Rai Dinesh Thapa Shishir Thapa Kumar Chinnappan Amit Kumar Dubey Suraj Gurung Aman Yadav Utpalkant Kumar Ranjay Kumar department of Radiation oncology Purbanchal Cancer Hospital Jhapa Nepal department of Radiology Purbanchal Cancer Hospital Jhapa Nepal Deapartment of Pathology Purbanchal Cancer Hospital Jhapa Nepal department of Neurosurgery Purbanchal Cancer Hospital Jhapa Nepal

Introduction: radiotherapy (RT) is a vital cancer treatment modality for both curative and palliative purposes. Nepal is a developing country with a population of around 30 million people. Cancer affects 100 - 120 people out of every 100,000, and the figure is increasing. The number of radiation facility machines in the country is still countable in fingers. Purbanchal Cancer Hospital, Nepal is the first comprehensive cancer facility capable of performing stereotactic radiosurgery (SRS). Our facility has cutting-edge Varian Truebeam Linear Accelerators with millennium MLC, which makes SRS and SRT’S for intracranial lesions such as small benign and malignant tumors much easier. In addition to SRS, we are the pioneers of SBRT for lung using 4DCT, interstitial & intraluminal brachytherapy, RPM Gated & DIBH modalities in Nepal. Methods & Materials: The purpose of this study is to share our experience in establishing an SRS facility in the country, which includes training the RT team on the importance of process accuracy, patient selection, patient assessment, mould preparation, and describing image data acquisition, target, and organ at risk delineation on CT and MRI images, treatment planning process, and quality assurance. Results & Discussion: The plans for all SRS and SRT cases are based on target coverage, OAR sparing, hotspot inside the target, conformity index, heterogeneity index, and dose fall off. To select the final plan, we used strict passing criteria such as a conformity index Paddick (CIPaddick) more than 0.85, a falloff between 100% and 50% of less than 5.5 mm (maximum 6 mm in irregular targets), and a hotspot inside the target between 115 to 140 percent, as per clinical standards. In addition, we determined the CILomax and CIRTOG for each case. Passing criteria for verification plans are set as minimum of 95% for a 2% percentage dose difference (% DD) and a 2-mm distance to an agreement (DTA). We also gathered demographic data from patients treated in t

关键词： Conformity Index Double Shell Positioning System Electronic Portal Imaging Device Linear Accelerator Millennium MLC Octavius Detector 1500 Setup Field

Assessment the Optimal Effect of Time of Repetition: Extrinsic Pulse Parameter on Gd-DTPA Enhanced, Spin-Echo T1-Weighted MR Images under Low Magnetic Field Strength

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International Journal of Medical physics, clinical Engineering and Radiation oncology 2016年第3期5卷 196-203页

作者： Bimali Sanjeevani Weerakoon Toshiaki Osuga Takehisa Konishi Graduate School of Advanced Integration Science Chiba University Chiba Japan department of Radiography/radiotherapy Faculty of Allied Health Sciences University of Peradeniya Peradeniya Sri Lanka Center for Frontier Medical Engineering Chiba University Chiba Japan

The contrast agent concentration, the time of repetition (TR) and magnetic field strength are significant parameters that influence for the accurate signal intensity (SI) in quantitative Magnetic Resonance Imaging (MRI). Therefore, this study was conducted to investigate and refine the dependence and the optimal effect of Time of Repetition (TR) on the relationship between signal intensity and Gd-DTPA (Gadolinium-diethylene-triaminepenta-acetic acid) concentration, after applying two-dimensional (2D) Spin Echo (SE) pulse sequence under low-field MRI. In addition to that, the optimal concentration of Gd-DTPA at given sequence parameters at low-field MRI was also evaluated. A water-filled phantom was constructed for a range of Gd-DTPA concentrations (0 - 6 mmol/L) and the mean signal intensities (SIs) were assessed in the defined region of interest on T1-weighted images with different TR values (40 - 2000 ms). The generated signal-concentration curves for Gd-DTPA revealed that increasing TR was associated with the increase of the overall SIs and the maximum relationship between SI to concentration. Moreover, the required Gd-DTPA concentration to produce the maximum SI was associated to decrease with the increase of TR. In addition to this, the application of beyond 100 ms TR values in this study with relatively higher concentrations (beyond 1 - 2 mmol/L) has resulted predominantly non-linear patterns in the signal-concentration curves and it appears the saturation or decay of the SIs due to T2 effect. From these results, it can be suggested that the selection of relatively lower Gd-DTPA concentration ( mmol/L) with less than 800 ms (<800 ms) TR values can produce a better linear relationship between the concertation and SIs in T1-weighted SE low field contrast-enhanced MRI. Furthermore, this study also outlined the significance and necessity of the optimization of TR in SE sequence in low field MRI prior to a particular examination.

关键词： Gd-DTPA Concentration Spin Echo Pulse Sequence Signal Intensity Time of Repetition T1-Weighted Images Low Field MRI

Treatment of Massive Low-Grade Chondrosarcoma of Nasal Septum with Helical Tomotherapy: A Case Report

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International Journal of Medical physics, clinical Engineering and Radiation oncology 2016年第4期5卷 263-269页

作者： Hamit Basaran Timur Koca Sibel Karaca Ozlem Eser K&iota l&iota nc Fikriye Gul Karauc Okan Ö zdemir Ozan Kuduban Arzu Tatar Sare Ş ipal department of Radiation oncology Regional Training and Research Hospital Erzurum Turkey department of Otorhinolaryngology Regional Training and Research Hospital Erzurum Turkey department of Otorhinolaryngology Ataturk University Faculty of Medicine Erzurum Turkey department of Pathology Ataturk University Faculty of Medicine Erzurum Turkey

Chondrosarcomas are malignant bone tumors which develop as a cartilaginous differentiation of primary mesenchymal cells and the second most frequently seen malignant tumor of the bone after osteosarcoma. These malignancies are slowly growing non-epithelial tumors with unknown etiology and most frequently seen during the 4 decades of life. They are frequently localized on pelvis, ribs and long bones. Nasal septum CSs are very rarely seen malignancies. They originate from septal mucosa or cartilage and it is difficult to make a diagnosis unless they reach a certain size. A few cases of CSs with nasal septum have been reported in the literature. In cases of CSs, surgery is the gold standard treatment modality;however in surgically unresectable cases or close to margins, radiotherapy plays a significant role in primary and adjuvant treatment. Based on the position of the tumor in head and neck and extremely closeness of the tumor to vital organs as optic nerve, chiasm and brain, image guided-intensity modulated radiation therapy (IG-IMRT) becomes very effective and reliable modalities and may be a favorable treatment alternative.

关键词： Chondrosarcoma Image Guided Intensity Modulated Radiation Therapy