This document discusses image-guided radiotherapy (IGRT) for gynecologic malignancies. It begins by defining IGRT and noting that its definition is not standardized. It then discusses various imaging modalities that can be used for IGRT, including CT, MRI, PET, and ultrasound. In particular, it explores how these advanced imaging techniques can help with target delineation and treatment delivery verification. It also examines different IGRT approaches like planar, volumetric, and adaptive IGRT. Adaptive IGRT holds promise for adjusting treatment plans based on tumor response over the course of therapy but faces technical challenges that require further study.
The document discusses advances in radiation therapy for lung cancer including intensity modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT), and stereotactic radiotherapy (SRT). IGRT uses daily imaging to precisely target tumors and reduces margins needed around tumors. SRT delivers very high radiation doses in one to five fractions directly to tumors, achieving high local control rates for stage I lung cancer. Tomotherapy is highlighted as it provides IGRT capabilities and can perform SRT without needing fiducial markers for targeting.
4D-IGRT involves accounting for tumor motion during radiation therapy delivery. It uses 4D computed tomography (4D CT) imaging, which captures tumor position at different respiratory phases. This allows delineation of an internal target volume (ITV) that encompasses the full range of tumor motion. Treatment can then be delivered over the entire respiratory cycle or gated to a specific phase such as end-exhalation using respiratory tracking systems. The goal is to ensure accurate radiation delivery while minimizing doses to surrounding healthy tissues.
1) The document discusses perspectives on image-guided radiation therapy (IGRT) from physicians and physicists at the University of California San Diego (UCSD).
2) UCSD has implemented IGRT using both planar kV imaging and volumetric cone-beam CT (CBCT) primarily for prostate and gynecological cancers.
3) IGRT provides benefits of improved target localization and the potential for treatment adaptation if tumor size changes over the course of treatment are detected. However, proper quality assurance is needed when implementing an IGRT program.
This document discusses image-guided radiation therapy (IGRT) and its evolution and applications. It begins by defining IGRT as external beam radiation therapy using imaging prior to each treatment fraction to verify patient positioning. IGRT allows for reduction of safety margins by compensating for set-up errors and organ motion. The document then reviews the history of IGRT from early portal imaging to modern cone-beam CT and other volumetric imaging techniques. It provides examples of IGRT protocols and clinical outcomes for sites such as prostate, lung, liver, and central nervous system tumors.
This document discusses the integration of intensity-modulated radiation therapy (IMRT) and brachytherapy in the treatment of cervical cancer. It notes that while IMRT and brachytherapy were once seen as competing approaches, they can be integrated to provide comprehensive adaptive radiation treatment. Several studies demonstrate the tumor shrinkage observed during both external beam radiation and brachytherapy, allowing opportunities for treatment adaptation. Overcoming technical challenges like deformable image registration will be needed to enable daily adaptive IMRT integrated with adaptive brachytherapy planning based on imaging. This has the potential to further improve outcomes for cervical cancer patients.
This document discusses prostate motion and its impact on image-guided radiotherapy for prostate cancer. It finds that the rectum is a major source of interfractional prostate variation. Strategies like rectal emptying can help reduce shifts. Daily imaging allows for reduced planning target volume margins and decreased rectal toxicity despite dose escalation. However, optimal clinical target volume to planning target volume expansions remain unclear due to factors like extracapsular extension and residual errors. Different image guidance methods each have benefits and limitations for margin reduction and dose escalation in prostate cancer radiotherapy.
This document discusses quality assurance procedures for cone beam computed tomography (CBCT) imaging. It outlines the responsibilities of physicians, medical physicists, and radiation therapists in reviewing CBCT images and ensuring proper patient positioning. Daily quality assurance checks involve verifying safety interlocks and geometric accuracy using a positioning cube. Monthly quality assurance of image quality is performed by medical physicists using a Catphan phantom to check for uniformity, spatial resolution, low contrast visibility, and registration accuracy. Maintaining high image quality standards through a regular quality assurance program is important for correct patient localization.
The document discusses advances in radiation therapy for lung cancer including intensity modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT), and stereotactic radiotherapy (SRT). IGRT uses daily imaging to precisely target tumors and reduces margins needed around tumors. SRT delivers very high radiation doses in one to five fractions directly to tumors, achieving high local control rates for stage I lung cancer. Tomotherapy is highlighted as it provides IGRT capabilities and can perform SRT without needing fiducial markers for targeting.
4D-IGRT involves accounting for tumor motion during radiation therapy delivery. It uses 4D computed tomography (4D CT) imaging, which captures tumor position at different respiratory phases. This allows delineation of an internal target volume (ITV) that encompasses the full range of tumor motion. Treatment can then be delivered over the entire respiratory cycle or gated to a specific phase such as end-exhalation using respiratory tracking systems. The goal is to ensure accurate radiation delivery while minimizing doses to surrounding healthy tissues.
1) The document discusses perspectives on image-guided radiation therapy (IGRT) from physicians and physicists at the University of California San Diego (UCSD).
2) UCSD has implemented IGRT using both planar kV imaging and volumetric cone-beam CT (CBCT) primarily for prostate and gynecological cancers.
3) IGRT provides benefits of improved target localization and the potential for treatment adaptation if tumor size changes over the course of treatment are detected. However, proper quality assurance is needed when implementing an IGRT program.
This document discusses image-guided radiation therapy (IGRT) and its evolution and applications. It begins by defining IGRT as external beam radiation therapy using imaging prior to each treatment fraction to verify patient positioning. IGRT allows for reduction of safety margins by compensating for set-up errors and organ motion. The document then reviews the history of IGRT from early portal imaging to modern cone-beam CT and other volumetric imaging techniques. It provides examples of IGRT protocols and clinical outcomes for sites such as prostate, lung, liver, and central nervous system tumors.
This document discusses the integration of intensity-modulated radiation therapy (IMRT) and brachytherapy in the treatment of cervical cancer. It notes that while IMRT and brachytherapy were once seen as competing approaches, they can be integrated to provide comprehensive adaptive radiation treatment. Several studies demonstrate the tumor shrinkage observed during both external beam radiation and brachytherapy, allowing opportunities for treatment adaptation. Overcoming technical challenges like deformable image registration will be needed to enable daily adaptive IMRT integrated with adaptive brachytherapy planning based on imaging. This has the potential to further improve outcomes for cervical cancer patients.
This document discusses prostate motion and its impact on image-guided radiotherapy for prostate cancer. It finds that the rectum is a major source of interfractional prostate variation. Strategies like rectal emptying can help reduce shifts. Daily imaging allows for reduced planning target volume margins and decreased rectal toxicity despite dose escalation. However, optimal clinical target volume to planning target volume expansions remain unclear due to factors like extracapsular extension and residual errors. Different image guidance methods each have benefits and limitations for margin reduction and dose escalation in prostate cancer radiotherapy.
This document discusses quality assurance procedures for cone beam computed tomography (CBCT) imaging. It outlines the responsibilities of physicians, medical physicists, and radiation therapists in reviewing CBCT images and ensuring proper patient positioning. Daily quality assurance checks involve verifying safety interlocks and geometric accuracy using a positioning cube. Monthly quality assurance of image quality is performed by medical physicists using a Catphan phantom to check for uniformity, spatial resolution, low contrast visibility, and registration accuracy. Maintaining high image quality standards through a regular quality assurance program is important for correct patient localization.
1) IGRT uses cone beam CT (CBCT) imaging to improve patient positioning accuracy and account for interfraction motion, allowing for dose escalation and hypofractionated treatments.
2) Respiratory gating uses external surrogates and binning to characterize tumor motion over the respiratory cycle and gate treatment to specific phases to reduce motion-induced targeting errors.
3) The combination of IGRT and respiratory gating can help oncologists see and hit moving tumors, enabling safer dose escalation for treatments like SBRT.
A short overview of Image Guided Radiotherapy process in Lung Cancer presented at TMC Kolkata circa 2016. Basic principles and concepts as well as examples are outlined.
Research into the effectiveness of daily image guided radiotherapy on the pro...Genesis Care
This study assessed different cone beam CT (CBCT) imaging protocols for image-guided radiotherapy in prostate cancer patients. 844 CBCT images from 20 patients undergoing radiotherapy were analyzed. Daily online CBCT verification provided the best target coverage and lowest rectal dose compared to weekly online or offline protocols. Daily imaging helped improve target coverage, with one patient having inadequate coverage for 6 fractions with a weekly protocol versus just 1 fraction with daily imaging. The study concludes that daily online CBCT verification improves target coverage and reduces rectal dose for prostate cancer IGRT.
This document discusses the use of intensity-modulated radiation therapy (IMRT) for treating cervix cancer. It notes that IMRT is rarely used currently but could help reduce dose to normal tissues and potentially replace brachytherapy. The document outlines the need for accurate target volume definition using imaging like MRI and CT. It also describes the inverse planning process for IMRT and challenges like organ motion. While IMRT may help spare organs at risk, issues like increased leakage, integral dose and treatment time must be considered.
1. IMRT allows delivering different dose levels to multiple tumor targets simultaneously.
2. Advanced MRI techniques like DCE and T2 mapping can help better identify diseased sites and define boost targets for IMRT planning.
3. The presenter is working to incorporate MRI data like functional MRI into the radiotherapy planning process to help optimize dose distribution and improve patient outcomes.
IGRT is a radiation therapy process that uses imaging to ensure accurate patient positioning and alignment. Frequent imaging during treatment, such as with CBCT, allows corrections to be made for set-up errors and organ motion. This improves the precision of radiation delivery to the target volume while reducing doses to healthy tissues, leading to better treatment outcomes and fewer side effects.
This document discusses Image Guided Radiation Therapy (IGRT). It begins by explaining that radiotherapy has traditionally used imaging for treatment planning and execution when the target is not on the surface. It then describes various IGRT technologies, dividing them into non-radiation based systems like ultrasound, cameras, electromagnetic tracking and MRI; and radiation based systems like EPID, CBCT, fan beam KVCT and MVCT. These systems provide improved target localization and allow for corrections. IGRT aims to reduce errors and improve precision of radiotherapy.
IGRT (Image-Guided Radiotherapy) uses x-rays and scans before and during radiation therapy to more precisely target tumors and reduce radiation exposure to healthy tissues. IGRT allows doctors to detect and correct errors in patient positioning and account for changes in tumor size or position during treatment. This improves accuracy and allows higher radiation doses to tumors or reduced margins around tumors, lowering toxicity risks and improving patient outcomes and quality of life. While requiring additional resources, IGRT has become a standard part of radiation therapy by improving precision and reducing uncertainties.
The document discusses the evolution of breast cancer treatment from radical mastectomies to more conservative local treatments like lumpectomy and sentinel node biopsy, as well as the use of accelerated partial breast irradiation techniques like intraoperative radiotherapy (ELIOT) to further reduce treatment times and exposure to radiation. It presents data from trials at the European Institute of Oncology demonstrating the safety and effectiveness of ELIOT compared to conventional external beam radiotherapy for early-stage breast cancer.
Future Developments In Radiation Therapy For Prostate Cancerfondas vakalis
This document discusses future developments in radiation therapy for prostate cancer. It summarizes that dose escalation improves disease control but can increase toxicity risks. Newer radiation techniques like IMRT, fiducial markers, on-board imaging, and protons may allow safer dose escalation by better sparing nearby organs. Further refinements include selective dose painting within the prostate using MRI/MRS imaging fusion to guide treatment. The document also reviews the history and ongoing improvements in brachytherapy techniques for localized prostate treatments.
Advanced Radiotherapy in Cancer Care in Central India- ALEXIS NAGPUR 2017Puneet Seth
Dr. Puneet Seth is a radiation oncologist who has worked at several hospitals in India and abroad, treating patients with a variety of advanced radiotherapy techniques including IMRT, IGRT, SBRT, RapidArc, CyberKnife, and HDR brachytherapy. He is currently a consultant radiation oncologist at Alexis Multi-speciality Hospital in Nagpur, India. The document provides details about Dr. Seth's education and work experience, the advanced radiotherapy technologies and techniques available, and how they can be used to effectively treat many types of cancer.
Technical Advances in radiotherapy for Lung (and liver) Cancerspa718
This document summarizes recent technical advances in radiotherapy for lung and liver cancer, including: 4DCT imaging to account for tumor motion; motion management techniques like gating and breath-holding; intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) to improve dose conformity; image-guided radiation therapy (IGRT) to reduce margins and enable adaptations; and proton therapy which may further reduce normal tissue dose due to its physical properties, though proton techniques are still evolving to address motion and anatomical changes. The document outlines the benefits and challenges of each technique through examples and studies.
This document discusses image-guided radiation therapy (IGRT) and various IGRT techniques. It describes how IGRT aims to increase the accuracy and precision of radiotherapy delivery by applying image-based target relocalization. Common IGRT techniques mentioned include portal imaging, on-board cone-beam CT (CBCT), in-room CT, ultrasound and real-time tumor tracking. CBCT allows visualization of the tumor location using kilovoltage or megavoltage X-rays rotating around the patient. Real-time tumor tracking involves synchronizing radiation delivery with the respiratory cycle using implanted fiducial markers and fluoroscopy.
Dr. Puneet Seth is a radiation oncologist who has worked in several hospitals in India implementing new radiotherapy techniques like IMRT and IGRT using Varian linear accelerators. He is now at BSR Cancer Hospital in Bhilai, Chhattisgarh where he plans to install a new unique Varian linear accelerator by end of 2012/2013 that will enable techniques like RapidArc and IGRT to treat cancer patients in the region. The new setup will help improve treatment planning and delivery compared to the existing older cobalt unit through features like the Millennium MLC and integrated CT simulation.
IGRT shows promise for reducing toxicity and allowing dose escalation when used with brachytherapy for gynecologic cancers. However, IMRT alone is not recommended for primary cervical cancer treatment due to the complex organ motion and tumor regression over treatment. Image guidance is most important for brachytherapy to accurately target the tumor while sparing organs at risk. Further research is still needed to determine the optimal use of IMRT and image guidance for gynecologic cancers.
Basic information about Elekta and its familiar with xvi and Iviewgt protocols and there import and defining the Target area clip box registration along with HEXAPOD 6Dof couch & Apex Dmlc setup
PET and radiotherapy for head and neck cancer provides essential information for target volume selection and delineation. Functional imaging with FDG-PET is more sensitive and specific than CT or MRI for detecting metastatic lymph nodes. Integrating PET into the treatment planning process allows more accurate gross tumor volume definition compared to CT alone. Adaptive radiotherapy using serial PET imaging during treatment may enable biological target volume adaptation and improved dose distribution optimization. Future applications include exploring other PET tracers and integrating multi-modality image registration with dose adaptation.
1) Intensity modulated radiation therapy (IMRT) is a technique that uses computer software to conform the radiation dose to the shape of the tumor, reducing dose to surrounding normal tissues and decreasing toxicity.
2) Numerous studies have shown IMRT provides better sparing of the small bowel, bladder, and rectum compared to conventional radiation for gynecologic cancers.
3) IMRT may allow dose escalation to high risk sites or involved nodes while maintaining normal tissue doses. Some studies have also investigated using IMRT as an alternative to brachytherapy boosts.
4) Clinical studies suggest IMRT results in low rates of acute gastrointestinal and genitourinary toxicity compared to conventional radiation for
The document provides instructions for taking a photo using a monitor by sitting in front of it, looking directly at the lens, and pressing "TAKE PHOTO" without moving. It then claims this is a test of a new technology that converts monitors into cameras. Further instructions are given to move slightly left and smile for the photo before a message indicates the photo ability is fake and to get back to work.
1) IGRT uses cone beam CT (CBCT) imaging to improve patient positioning accuracy and account for interfraction motion, allowing for dose escalation and hypofractionated treatments.
2) Respiratory gating uses external surrogates and binning to characterize tumor motion over the respiratory cycle and gate treatment to specific phases to reduce motion-induced targeting errors.
3) The combination of IGRT and respiratory gating can help oncologists see and hit moving tumors, enabling safer dose escalation for treatments like SBRT.
A short overview of Image Guided Radiotherapy process in Lung Cancer presented at TMC Kolkata circa 2016. Basic principles and concepts as well as examples are outlined.
Research into the effectiveness of daily image guided radiotherapy on the pro...Genesis Care
This study assessed different cone beam CT (CBCT) imaging protocols for image-guided radiotherapy in prostate cancer patients. 844 CBCT images from 20 patients undergoing radiotherapy were analyzed. Daily online CBCT verification provided the best target coverage and lowest rectal dose compared to weekly online or offline protocols. Daily imaging helped improve target coverage, with one patient having inadequate coverage for 6 fractions with a weekly protocol versus just 1 fraction with daily imaging. The study concludes that daily online CBCT verification improves target coverage and reduces rectal dose for prostate cancer IGRT.
This document discusses the use of intensity-modulated radiation therapy (IMRT) for treating cervix cancer. It notes that IMRT is rarely used currently but could help reduce dose to normal tissues and potentially replace brachytherapy. The document outlines the need for accurate target volume definition using imaging like MRI and CT. It also describes the inverse planning process for IMRT and challenges like organ motion. While IMRT may help spare organs at risk, issues like increased leakage, integral dose and treatment time must be considered.
1. IMRT allows delivering different dose levels to multiple tumor targets simultaneously.
2. Advanced MRI techniques like DCE and T2 mapping can help better identify diseased sites and define boost targets for IMRT planning.
3. The presenter is working to incorporate MRI data like functional MRI into the radiotherapy planning process to help optimize dose distribution and improve patient outcomes.
IGRT is a radiation therapy process that uses imaging to ensure accurate patient positioning and alignment. Frequent imaging during treatment, such as with CBCT, allows corrections to be made for set-up errors and organ motion. This improves the precision of radiation delivery to the target volume while reducing doses to healthy tissues, leading to better treatment outcomes and fewer side effects.
This document discusses Image Guided Radiation Therapy (IGRT). It begins by explaining that radiotherapy has traditionally used imaging for treatment planning and execution when the target is not on the surface. It then describes various IGRT technologies, dividing them into non-radiation based systems like ultrasound, cameras, electromagnetic tracking and MRI; and radiation based systems like EPID, CBCT, fan beam KVCT and MVCT. These systems provide improved target localization and allow for corrections. IGRT aims to reduce errors and improve precision of radiotherapy.
IGRT (Image-Guided Radiotherapy) uses x-rays and scans before and during radiation therapy to more precisely target tumors and reduce radiation exposure to healthy tissues. IGRT allows doctors to detect and correct errors in patient positioning and account for changes in tumor size or position during treatment. This improves accuracy and allows higher radiation doses to tumors or reduced margins around tumors, lowering toxicity risks and improving patient outcomes and quality of life. While requiring additional resources, IGRT has become a standard part of radiation therapy by improving precision and reducing uncertainties.
The document discusses the evolution of breast cancer treatment from radical mastectomies to more conservative local treatments like lumpectomy and sentinel node biopsy, as well as the use of accelerated partial breast irradiation techniques like intraoperative radiotherapy (ELIOT) to further reduce treatment times and exposure to radiation. It presents data from trials at the European Institute of Oncology demonstrating the safety and effectiveness of ELIOT compared to conventional external beam radiotherapy for early-stage breast cancer.
Future Developments In Radiation Therapy For Prostate Cancerfondas vakalis
This document discusses future developments in radiation therapy for prostate cancer. It summarizes that dose escalation improves disease control but can increase toxicity risks. Newer radiation techniques like IMRT, fiducial markers, on-board imaging, and protons may allow safer dose escalation by better sparing nearby organs. Further refinements include selective dose painting within the prostate using MRI/MRS imaging fusion to guide treatment. The document also reviews the history and ongoing improvements in brachytherapy techniques for localized prostate treatments.
Advanced Radiotherapy in Cancer Care in Central India- ALEXIS NAGPUR 2017Puneet Seth
Dr. Puneet Seth is a radiation oncologist who has worked at several hospitals in India and abroad, treating patients with a variety of advanced radiotherapy techniques including IMRT, IGRT, SBRT, RapidArc, CyberKnife, and HDR brachytherapy. He is currently a consultant radiation oncologist at Alexis Multi-speciality Hospital in Nagpur, India. The document provides details about Dr. Seth's education and work experience, the advanced radiotherapy technologies and techniques available, and how they can be used to effectively treat many types of cancer.
Technical Advances in radiotherapy for Lung (and liver) Cancerspa718
This document summarizes recent technical advances in radiotherapy for lung and liver cancer, including: 4DCT imaging to account for tumor motion; motion management techniques like gating and breath-holding; intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) to improve dose conformity; image-guided radiation therapy (IGRT) to reduce margins and enable adaptations; and proton therapy which may further reduce normal tissue dose due to its physical properties, though proton techniques are still evolving to address motion and anatomical changes. The document outlines the benefits and challenges of each technique through examples and studies.
This document discusses image-guided radiation therapy (IGRT) and various IGRT techniques. It describes how IGRT aims to increase the accuracy and precision of radiotherapy delivery by applying image-based target relocalization. Common IGRT techniques mentioned include portal imaging, on-board cone-beam CT (CBCT), in-room CT, ultrasound and real-time tumor tracking. CBCT allows visualization of the tumor location using kilovoltage or megavoltage X-rays rotating around the patient. Real-time tumor tracking involves synchronizing radiation delivery with the respiratory cycle using implanted fiducial markers and fluoroscopy.
Dr. Puneet Seth is a radiation oncologist who has worked in several hospitals in India implementing new radiotherapy techniques like IMRT and IGRT using Varian linear accelerators. He is now at BSR Cancer Hospital in Bhilai, Chhattisgarh where he plans to install a new unique Varian linear accelerator by end of 2012/2013 that will enable techniques like RapidArc and IGRT to treat cancer patients in the region. The new setup will help improve treatment planning and delivery compared to the existing older cobalt unit through features like the Millennium MLC and integrated CT simulation.
IGRT shows promise for reducing toxicity and allowing dose escalation when used with brachytherapy for gynecologic cancers. However, IMRT alone is not recommended for primary cervical cancer treatment due to the complex organ motion and tumor regression over treatment. Image guidance is most important for brachytherapy to accurately target the tumor while sparing organs at risk. Further research is still needed to determine the optimal use of IMRT and image guidance for gynecologic cancers.
Basic information about Elekta and its familiar with xvi and Iviewgt protocols and there import and defining the Target area clip box registration along with HEXAPOD 6Dof couch & Apex Dmlc setup
PET and radiotherapy for head and neck cancer provides essential information for target volume selection and delineation. Functional imaging with FDG-PET is more sensitive and specific than CT or MRI for detecting metastatic lymph nodes. Integrating PET into the treatment planning process allows more accurate gross tumor volume definition compared to CT alone. Adaptive radiotherapy using serial PET imaging during treatment may enable biological target volume adaptation and improved dose distribution optimization. Future applications include exploring other PET tracers and integrating multi-modality image registration with dose adaptation.
1) Intensity modulated radiation therapy (IMRT) is a technique that uses computer software to conform the radiation dose to the shape of the tumor, reducing dose to surrounding normal tissues and decreasing toxicity.
2) Numerous studies have shown IMRT provides better sparing of the small bowel, bladder, and rectum compared to conventional radiation for gynecologic cancers.
3) IMRT may allow dose escalation to high risk sites or involved nodes while maintaining normal tissue doses. Some studies have also investigated using IMRT as an alternative to brachytherapy boosts.
4) Clinical studies suggest IMRT results in low rates of acute gastrointestinal and genitourinary toxicity compared to conventional radiation for
The document provides instructions for taking a photo using a monitor by sitting in front of it, looking directly at the lens, and pressing "TAKE PHOTO" without moving. It then claims this is a test of a new technology that converts monitors into cameras. Further instructions are given to move slightly left and smile for the photo before a message indicates the photo ability is fake and to get back to work.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
This document lists various brand names and product categories without context or details. It mentions brands like Lancôme, Nike, Burger King, and categories such as tobacco, sports, beverages, dental care, bags, and miscellaneous items along with some product names like Harry's Bread and window cleaner.
Varian is the leading provider of radiation therapy solutions with 60% of the global market share. To maintain its position amid increasing competition, Varian focuses on developing new precision treatment technologies like IMRT and IGRT. Recent products like RapidArc and the Novalis TX collaboration with BrainLab expand Varian's offerings and directly compete with solutions from Elekta, Siemens, and Accuray. Varian also invests in proton therapy to capitalize on its long-term advantages over other technologies and sustain growth over the next five years.
1) The document describes a conceptual journey through scales of size from 1 meter to billions of light years and back down to fractions of a nanometer.
2) It explores scales from the size of leaves to the size of galaxies and discusses what can be observed at each magnitude of size.
3) The document suggests that the laws of the universe remain consistent across all scales and ponders fundamental questions about humanity's place and understanding of the cosmos.
Eric Grohe es un artista que pinta murales hiperrealistas de gran escala directamente en paredes. Transforma paredes ordinarias en obras de arte tridimensionales mediante el uso de detalles finos y colores realistas. Eric trabaja solo en la mayoría de los proyectos, investigando y diseñando cada pieza desde cero.
Early Stage Nsclc The Role Of Chemotherapyfondas vakalis
- The document discusses the role of chemotherapy in early stage non-small cell lung cancer (NSCLC), including adjuvant and induction chemotherapy.
- Several studies on induction chemotherapy found it to be safe and feasible prior to surgery, with high rates of tumor response and similar postoperative complications compared to surgery alone. However, larger phase III studies are still ongoing.
- The optimal use of chemotherapy, whether adjuvant or induction, in early stage NSCLC remains unclear and requires completion of current clinical trials.
Asco 2006 Update Genitourinary Cancer Selected Abstractsfondas vakalis
The document summarizes several studies on targeted therapies for kidney cancer presented at the 2006 ASCO conference. Key findings include:
- Sunitinib and temsirolimus were shown to be superior to interferon for metastatic kidney cancer in phase 3 trials, with longer progression-free and overall survival.
- The TARGET trial found sorafenib increased progression-free survival compared to placebo in advanced RCC and improved overall survival after patients on placebo crossed over.
- A global phase 3 trial found temsirolimus alone or with interferon improved overall survival over interferon in poor-risk metastatic RCC patients.
This document discusses considering buying a new Mercedes and previews its latest model, noting being impressed by the specifications but concerned about it becoming a target for thieves. It reveals the car includes an anti-theft device as standard that would deter thieves from breaking into the car.
The document discusses survey results from clinical investigators and practicing oncologists on their use of adjuvant chemotherapy regimens for breast cancer patients. The most common regimens used were anthracycline-containing regimens like AC for node-negative patients and TAC for node-positive patients. More clinicians were using taxane-containing regimens like AC followed by paclitaxel or docetaxel-cyclophosphamide over time. Most were also aware of and using genomic assays like Oncotype DX or MammaPrint to guide treatment decisions.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
Monte Carlo And Ct Interface For Medical Treatment Plansfondas vakalis
The document discusses using Geant4, an open-source Monte Carlo simulation toolkit, to develop a general-purpose dosimetry system for medical treatment planning with brachytherapy applications. Key goals are precision, realistic geometry and material modeling from CT images, and speed for clinical use. The system would provide an alternative to commercial software which uses approximations and is not flexible or affordable for all applications like hadron therapy or niche uses. Geant4 capabilities enable accurate modeling of physics interactions down to low energies needed for medical simulations.
Treatment Of Potentially Resectable Pancreatic Cancerfondas vakalis
1. Conventional treatment for resectable pancreatic cancer involving surgery and adjuvant chemoradiation has shown limited success, with few long-term survivors and significant treatment-related toxicity.
2. Preoperative chemoradiation using gemcitabine has shown promise in improving resectability and survival rates compared to postoperative chemoradiation or surgery alone, while avoiding unnecessary surgeries.
3. Combining gemcitabine with newer chemotherapy agents like capecitabine may allow higher drug doses with reduced toxicity when combined with radiation, improving patient outcomes.
This document discusses the role of pulmonologists and thoracic surgeons in lung cancer radiosurgery. It begins by defining radiosurgery and comparing it to conventional radiation therapy. It then outlines potential roles for pulmonologists such as patient identification, fiducial marker placement for tracking tumor motion, and patient follow-up. Thoracic surgeons could also be involved in patient selection for clinical trials comparing radiosurgery to surgery. Both specialties require training to learn techniques like fiducial placement and participate in treatment planning. When trained, pulmonologists and surgeons can be reimbursed for their contributions to lung radiosurgery treatment.
Radiation oncology uses ionizing radiation to treat cancer. Radiation damages DNA directly or indirectly through free radicals, preferentially killing cancer cells. Radiation is produced by linear accelerators and delivered externally by photon beams in conventional fractionated radiotherapy or stereotactically. Newer techniques like IMRT conform doses better to tumors while avoiding normal tissues. Radiation can be delivered internally via brachytherapy sources placed in or near tumors. The goal is definitive cure or palliation; fractionation allows normal tissue recovery between doses. Different cancers have varying radiosensitivities requiring tailored doses and fractionation schemes.
Undoubtedly, the use of radiographic imaging has entirely revolutionized diagnosis and treatment planning in medical sciences. The role of imaging in oral malignancies can be broadly grouped into those used to evaluate primary disease and those to evaluate metastatic disease.
It is a useful tool for staging and management planning in oral cancers. Awareness of the presence of cervical node metastasis is important in treatment planning and in prognostic prediction for patients with head and neck cancer (HNC).
. Panoramic radiography (also called pan tomography or rotational radiography) is a radiographic technique for producing a single image of the facial structures that include both maxillary and mandibular arches and their supporting structures.
Undoubtedly, the use of radiographic imaging has entirely revolutionized the diagnosis and treatment planning in medical sciences. The role of imaging in oral malignancies can be broadly grouped in those used to evaluate primary disease and those to evaluate metastatic disease.
The role and techniques of MRI in gamma knife radiosurgery: a technologist’s ...Holly Chun
MRI plays a crucial role in gamma knife radiosurgery (GK) at multiple stages: pre-treatment to identify targets, during treatment planning to define targets and avoid critical structures, and post-treatment to assess results. MRI is used to visualize lesions, edema, and relevant anatomy with contrast and different weighted sequences. Images are used in treatment planning to determine dosage and angles of radiation delivery precisely to the target. MRI techniques aim to include all reference fiducials and the target area while positioning the patient comfortably to minimize image distortion.
This document discusses various imaging techniques used in periodontics, including radiography, digital radiography, subtraction radiography, panoramic imaging, CT scans, MRI, and bone scanning. Radiography is described as the most common and important technique for assessing periodontal disease as it provides information on bone levels, furcation involvement, and other factors. Digital radiography provides advantages over traditional films such as instant viewing and reduced radiation exposure.
This document provides information about Dr. Behgal K.S., a director of the Behgal Cancer Centre and Behgal's Radiation Training Institute in Mohali, India. It discusses radiation therapy and brachytherapy facilities and techniques available at Behgal Cancer Centre, including linear accelerators, HDR brachytherapy, IMRT, IGRT, stereotactic radiosurgery, and nuclear medicine capabilities. The document also outlines various clinical applications of radiation therapy and brachytherapy techniques for different cancer types.
A summary of recent innovations in radiation oncology focussing on the priniciples of different techniques and their application. An overview of clinical results has also been given
01 suh brain anatomy, planning and delivery hyderabad 2013 (cancer ci 2013) j...Dr. Vijay Anand P. Reddy
This document provides an overview of brain anatomy, advances in radiation therapy treatment planning and delivery for brain tumors, and methods to focus radiation dose on tumors while minimizing dose to healthy brain tissue. It discusses contouring important brain structures, use of imaging like CT and MRI in treatment planning, and the evolution of techniques like intensity modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT). It also reviews stereotactic radiosurgery and different technologies used like Gamma Knife and linear accelerators. The document concludes that understanding brain anatomy and dose constraints is essential for optimizing radiation delivery for brain tumors.
Image Processing in Measurement guided Radiotherapy and Geometric accuracyajayhakkumar
This document discusses image processing in measurement guided radiotherapy and geometric accuracy. It provides an outline on the history of x-rays and medical imaging, types of radiotherapy including 2D, 3DCRT, IMRT, IGRT and SRS. It describes the key steps involved in radiotherapy including patient positioning, imaging, treatment planning, dosimetry and treatment delivery. It emphasizes the importance of quality assurance for imaging and treatment machines to ensure geometric accuracy and highlights periodic training as important for all staff involved.
Multiparametric Quantitative MRI as a Metric for Radiation Treatment PlanningCrimsonpublishersCancer
Magnetic resonance imaging (MRI) provides excellent soft tissue contrast, and in combination with its quantitative functional imaging capability, this modality is ideal for use in radiotherapy. MRI images, either used directly or fused with CT, play an increasingly important role in contouring gross tumor volume (GTV) and organs at risk (OAR) in radiation treatment planning (RTP) systems. The soft tissue contrast of MRI images provides more accurate tumor delineation than CT, although CT images have sufficient geometrical stability and electron density information for accurate radiation treatment planning. Many vendors now offer 70 cm wide-bore MRI systems with dedicated radiofrequency (RF) coils and immobilization devices for RTP simulation comparable to CT simulators.
This document describes a study applying intensity modulated radiation therapy (IMRT) using independent jaws rather than a multi-leaf collimator for cancer patients in Dongnai General Hospital in Vietnam. IMRT plans were generated for a nasopharynx patient case using both conventional 3D conformal radiation therapy and jaw-only IMRT (JO-IMRT) techniques. The JO-IMRT plan provided better sparing of critical structures like the parotid glands and spinal cord compared to 3D-CRT. Measurement of the JO-IMRT plan delivery showed differences from calculated doses of less than 2.5%. The study aims to introduce JO-IMRT as a more economical and practical IMRT option for facilities
The vital importance of imaging techniques in radiation oncology now extends beyond diagnostic evaluation and treatment planning. Radiotherapy requires input from imaging for treatment planning and execution, when the treatment target is not located on the surface and, inspection and visual confirmation are not feasible. Traditional radiotherapy practices incorporate use of anatomic surface landmarks as well as radiologic correlation with 2D imaging in the form of port films or fluoroscopic imaging. Targets to be irradiated and normal tissues to be spared are delineated on CT scans in the planning process. Recent technical advances have enabled the integration of various imaging modalities into the everyday practice of radiotherapy directly at the linear accelerator. IGRT seeks to address geometric uncertainties in dose placement for target and normal tissues. It has become a routine part of current RT practice. Safe application of IGRT technology requires additional training and careful integration into the clinical process. IGRT reveals changes in anatomy during treatment which challenges conventional practices. IGRT facilitates the precise application of specialized irradiation techniques with narrow safety margins to radiosensitive organs.
The document discusses standards for precision in radiation oncology, including definitions of target volumes and dose reporting levels according to International Commission on Radiation Units and Measurements (ICRU) reports. It notes unresolved issues for 3D conformal radiation therapy and intensity-modulated radiation therapy, such as margins between gross tumor and clinical target volumes. The document recommends that a new ICRU report is needed to address these modern radiotherapy techniques and provide common guidelines.
Hybrid imaging refers to the fusion of images from two or more imaging modalities to provide complementary anatomical and functional information. PET/CT was the first widely used hybrid imaging technique, combining the functional imaging of PET with the anatomical details of CT. This allows clinicians to more accurately localize tracer uptake and stage diseases like cancer. More recently, PET/MRI has also emerged as a hybrid technique, offering soft tissue contrast superior to CT while avoiding additional radiation exposure. Both hardware-based scanners that acquire data simultaneously and software-based techniques that co-register images are used to generate hybrid images.
This document discusses fusion imaging, which combines images from different modalities to create a hybrid image. It describes fusion imaging techniques like PET-CT and SPECT-CT that merge functional imaging data with anatomical images. The primary advantage of fusion imaging is that it allows correlation of findings from two concurrent imaging modalities, providing both anatomical and functional/metabolic information in a single exam. Specifically, PET-CT fusion improves diagnostic accuracy and lesion localization by overcoming the limitations of each individual modality. In conclusion, combined PET-CT exams are more effective than PET alone for localizing lesions and differentiating normal variants from tumors.
MANAGEMENT OF VERTEBRAL BODY METASTATIC TUMOURS.pptxAlangsungyu Ajem
Management of vertebral body metastatic tumors typically involves a multidisciplinary approach. Spinal metastases are common, with up to 70% of cancer patients developing spinal metastases. Modern treatments include surgery, radiation therapy such as stereotactic body radiotherapy, and medical therapies like chemotherapy and hormone therapy. The goals of treatment are palliation through pain relief and preservation of neurological function and quality of life. Surgical indications include spinal instability, pain resistant to other therapies, and neurological deficits. Outcomes are often improved when surgery is combined with radiation.
Imaging Informatics refers to improving the efficiency, accuracy, and reliability of medical imaging services. It involves studying how medical image information is retrieved, analyzed, enhanced, and exchanged within radiology and other areas of medicine. Key areas include PACS, RIS, image processing, 3D visualization, and standards like DICOM that allow integration of imaging technologies. Open source software tools like ImageJ, ITK, and GemIdent provide platforms for medical image analysis.
Sixty percent of primary brain tumors are glial tumors, with two-thirds being high-grade. Radiotherapy plays an important role in treating brain tumors, especially for high-grade gliomas, residual disease after surgery, recurrent tumors, and some benign tumors. Techniques include conventional 2D radiotherapy, 3D conformal radiotherapy, stereotactic radiosurgery/radiotherapy using platforms like Gamma Knife or LINAC, and brachytherapy. Emerging techniques like proton beam therapy aim to further reduce radiation exposure to surrounding normal brain tissue. Selection of the right radiotherapy technique depends on the tumor type, location, and available technology.
This document discusses the use of intensity-modulated radiation therapy (IMRT) in the treatment of cervical cancer. It provides an overview of the history and technological advances in radiation therapy for cervical cancer. It then discusses several studies comparing IMRT to conventional radiation therapy, showing benefits of IMRT such as reduced toxicity and ability to escalate dose. The document also considers integrating IMRT and brachytherapy to further optimize treatment.
This document discusses pancreatic cancer and its treatment. It begins by stating that pancreatic cancer is most commonly diagnosed as locally advanced or metastatic. It then discusses the role of surgery, chemotherapy, and radiation therapy in the treatment of pancreatic cancer. It notes that the majority of surgically treated patients will have a recurrence, with a median survival of 15-20 months. The value of adjuvant and neoadjuvant therapy is debated. The document summarizes several clinical trials investigating chemotherapy and chemoradiation as adjuvant treatment after surgery. It also discusses neoadjuvant therapy and its potential advantages over adjuvant therapy. Emerging strategies discussed include induction chemotherapy followed by localized chemoradiation or second line therapy. The document concludes by describing modern radiation
This document provides information on the evaluation and treatment of metastatic bone disease and spinal cord compression. It discusses:
1. Common sites of bone metastases from various primary cancers. Imaging tools to evaluate bone metastases like x-rays, bone scans, CT, PET, and MRI scans are described.
2. A multi-disciplinary treatment approach is recommended, including medical treatment, surgery, radiotherapy, radionuclides, chemotherapy, and hormonal therapy.
3. Details are provided on conventional and advanced radiation therapy techniques for treating bone metastases and spinal cord compression, including stereotactic radiosurgery. Overall pain relief rates, time to pain relief, and the benefits of combining surgery and radiation therapy are
This document discusses stereotactic body radiotherapy (SBRT) for early stage lung cancer patients who cannot undergo surgery. It describes how SBRT delivers a high radiation dose to the tumor in just 1-5 sessions. Studies show SBRT provides improved tumor control compared to conventional radiotherapy, with surprisingly low toxicity. Early investigations found 3-year tumor control rates of 60-80% with SBRT, similar to surgery. Larger prospective trials of SBRT for medically inoperable early stage lung cancer patients demonstrated 3-year local control of 90-98% and low risks of side effects. SBRT provides an effective non-invasive alternative to surgery for these high-risk patients.
Spinal cord compression bhf aos study day mar 2014 finalfondas vakalis
This document provides an overview of malignant spinal cord compression (MSCC). It begins with a clinical case of a 56-year-old man initially diagnosed with back pain who is later found to have prostate cancer with MSCC. The talk then covers the anatomy of the spinal cord, definition and incidence of MSCC, typical symptoms, investigations including MRI, and treatment options like surgery, radiotherapy, and steroids. Outcomes are discussed, with the median survival being 6 months. The document concludes by outlining the key priorities for implementing NICE guidance on MSCC, including early detection and treatment of suspected cases as emergencies.
The document discusses breast cancer treatment recommendations including:
- No radiation therapy is recommended for early stage DCIS or invasive breast cancer.
- A tumor bed boost is recommended for higher risk patients but large trials found no survival difference with or without a boost.
- Hypofractionated whole breast radiation has become a standard option based on trials showing no difference in survival outcomes compared to conventional fractionation.
- Several trials investigated omitting axillary lymph node dissection or radiation with favorable results for select patient groups with low tumor burden.
This document discusses recent data on radiation therapy for prostate cancer. It begins by outlining the risk of prostate cancer development and mortality rates over time. It then examines risk stratification systems and treatment options for low, intermediate, and high risk disease. The document focuses on the benefits of dose escalation in radiation therapy, noting several studies that found higher radiation doses improved outcomes with acceptable toxicity when using newer techniques like IMRT. It also discusses hypofractionated regimens and image-guided radiation as ways to further improve the therapeutic ratio. In summary, this document reviews evidence that higher and more precisely delivered radiation doses can improve prostate cancer control while maintaining reasonable side effects.
The document discusses the benefits of meditation for reducing stress and anxiety. Regular meditation practice can help calm the mind and body by lowering heart rate and blood pressure. Studies have shown that meditating for just 10-20 minutes per day can have significant positive impacts on both mental and physical health over time.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms for those who already suffer from conditions like anxiety and depression.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms for those who already suffer from conditions like depression and anxiety.
This document summarizes a presentation on new perspectives on second-line therapy for non-small cell lung cancer (NSCLC). The presentation discusses current standards of care for second-line NSCLC, the unique needs of patients without targetable mutations, and emerging research findings. One study presented was the LUME-Lung 1 trial which found that the addition of the angiogenesis inhibitor nintedanib to docetaxel improved progression-free survival compared to placebo plus docetaxel in second-line NSCLC, with a significant overall survival benefit seen in the adenocarcinoma subgroup. Outstanding issues regarding biomarkers and the role of nintedanib in squamous cell carcinoma were discussed.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms for those who already suffer from conditions like depression and anxiety.
The document discusses the radiobiology behind dose fractionation in radiation therapy. It provides an overview of the linear quadratic model which describes how cell survival changes with dose and is used to determine biologically equivalent doses for different fractionation schedules. The model assumes equal effect per fraction but may not be accurate at high or low doses. Fractionation takes advantage of the four R's - repair, repopulation, redistribution, and reoxygenation - to better kill tumors while sparing normal tissues. The alpha/beta ratio indicates a tissue's sensitivity to fractionation and is used to estimate equivalent total doses for different fraction sizes.
The document discusses how tumor radiobiology may impact the move toward hypofractionation in radiation therapy. It reviews evidence that the classic linear-quadratic model does not fully capture tumor response at high radiation doses, and that other factors like vascular damage and immune effects become more important. Response heterogeneity between different tumor cell populations may also help explain why survival curves appear more linear at higher doses per fraction.
Rectal cancer treatment typically involves surgery. Local recurrence after conventional surgery occurs in 15-65% of cases on average. Long course preoperative chemoradiotherapy has been shown to reduce local recurrence rates compared to short course preoperative radiotherapy or radiotherapy alone. It increases local tumor control and survival rates with some toxicities but does not reduce colostomy rates. Preoperative chemoradiotherapy is superior to postoperative chemoradiotherapy in reducing local recurrence rates without affecting overall survival.
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotesPsychoTech Services
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Basavarajeeyam is a Sreshta Sangraha grantha (Compiled book ), written by Neelkanta kotturu Basavaraja Virachita. It contains 25 Prakaranas, First 24 Chapters related to Rogas& 25th to Rasadravyas.
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Adhd Medication Shortage Uk - trinexpharmacy.comreignlana06
The UK is currently facing a Adhd Medication Shortage Uk, which has left many patients and their families grappling with uncertainty and frustration. ADHD, or Attention Deficit Hyperactivity Disorder, is a chronic condition that requires consistent medication to manage effectively. This shortage has highlighted the critical role these medications play in the daily lives of those affected by ADHD. Contact : +1 (747) 209 – 3649 E-mail : sales@trinexpharmacy.com
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.
ABDOMINAL TRAUMA in pediatrics part one.drhasanrajab
Abdominal trauma in pediatrics refers to injuries or damage to the abdominal organs in children. It can occur due to various causes such as falls, motor vehicle accidents, sports-related injuries, and physical abuse. Children are more vulnerable to abdominal trauma due to their unique anatomical and physiological characteristics. Signs and symptoms include abdominal pain, tenderness, distension, vomiting, and signs of shock. Diagnosis involves physical examination, imaging studies, and laboratory tests. Management depends on the severity and may involve conservative treatment or surgical intervention. Prevention is crucial in reducing the incidence of abdominal trauma in children.
Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
Rasamanikya is a excellent preparation in the field of Rasashastra, it is used in various Kushtha Roga, Shwasa, Vicharchika, Bhagandara, Vatarakta, and Phiranga Roga. In this article Preparation& Comparative analytical profile for both Formulationon i.e Rasamanikya prepared by Kushmanda swarasa & Churnodhaka Shodita Haratala. The study aims to provide insights into the comparative efficacy and analytical aspects of these formulations for enhanced therapeutic outcomes.
1. IGRT in Gynecologic Malignancies
Arno J. Mundt MD
Professor and Chair
Department of Radiation Oncology
University of California San Diego
La Jolla CA
2. Image-Guided RT?
“Image guided” is non-informative
RT has always been guided by images
Definition of IGRT is not standardized and
is open to various interpretations
Global definition might include any aspect
of RT involving imaging, from fluoroscopic
simulation to CT-based planning, to
weekly port films
3. RTOG Research Plan 2002-2006
IGRT Committee Report
Michalski J, Purdy JA, Gaspar L, et al.
Int J Radiat Oncol Biol Phys 2001;51:60-5
“IGRT refers broadly to treatment delivery using
modern imaging methods, such as CT, MRI, PET and
Ultrasound, in target and non-target structures and in
RT definition, design and delivery…”
“IGRT includes, but is not limited to, 3DCRT, IMRT,
stereotactic radiosurgery, stereotactic RT, and
brachytherapy….”
4. Introduction
Recommend a more focused definition
Highlight the 2 most important roles of
imaging in modern RT:
Improved Target Delineation
Improved Treatment Delivery
5. IGRT Definition
Use of modern imaging modalities, especially those
incorporating functional or biological information, to
augment target delineation
and
Use of imaging, particularly in-room approaches, to
adjust for target motion and positional uncertainty,
and, potentially, to adapt treatment to tumor
response
6. New Frontier
Image-Guided Radiotherapy
Strong rationale in gynecologic tumors,
particularly when IMRT is used
CT is not ideal for imaging tumors and
normal tissues
Gynecology patients often difficult to setup
Considerable organ motion exists
Tumors shrink rapidly
7. Target Delineation
Traditional method planar (flouroscopic)
x-rays
External beam fields based on
visualized bony anatomy
Contrast used to define normal tissues
Brachytherapy doses prescribed to
specified “Points” based on applicator
position
8. 2D planning → Poor target coverage and excess normal
tissue exposure compared to 3D planning
Red
Journal
2006
43 cervical cancer pts
Evaluated adequacy of coverage of pelvic vessels
Surrogate for lymph nodes
Adequate: >15 mm vessel to block edge
41/43 (95%) inadequate coverage with 2D based
fields
24/43 (56%) too generous (> 2 cm)
Excess normal tissue exposure
9. Beyond CT Imaging
Interest now focused on more
sophisticated imaging for treatment
planning
Magnetic Resonance Imaging (MRI)
With ultra-small iron oxide particles (USPIO)
Positron Emission Tomography (PET)
18F-Deoxyglucose (FDG)
Or combined PET/CT units
10. Fe Oxide nano-particle
Taken up in benign lymph
nodes by macrophages
7 mm margin around
vessels encompassed 99%
of pelvic nodes
Red Journal (2005)
11. FDG-PET particularly useful to identify involved nodes
Boost to higher doses with IMRT
Mutic Red Journal (2003)
PET+ Nodes: 59.4 Gy/1.8 Gy fx
PET- Nodes: 50.4 Gy/1.53 Gy fx
Ahmed Red Journal (2004)
PET+ nodes: 60 Gy/2.4 Gy fx
PET- nodes: 45 Gy/1.8 Gy fx
12. More Advanced Imaging
Dynamic-Contrast MRI
(tumor hypoxia)
Cooper et al. Radiother
Oncol (2000)
1H-MR spectroscopy
(tumor vs normal tissue)
Okada et al. J MRI
Okada (2001)
(2001)
13. Alternative PET Tracers
Metabolic Abnormalities or Hypoxia
11C-Choline (tumor vs normal tissue)
11C-Methionine (amino acid transport)
60Cu-ATSM (hypoxia)
MRI FDG-PET 11C-Choline PET
Less uptake in normal tissues Torizuka J Nucl Med (2003)
11C-Choline imaging
14. Tumor hypoxia inversely
correlated with DFS and
OS
3y PFS normoxic (71%)
and hypoxix (28%)
Could be used to dose
paint during external
beam and brachytherapy
15. Normal Tissue Delineation
Novel imaging techniques also valuable
for normal tissue delineation
Roeske (2003)
MR-Spectroscopy to identify active
(red) marrow sites
Roeske (2005)
SPECT also useful for
active bone marrow delineation
17. T2* Pulse Echo MRI
“Fat Fraction”
Used to differentiate between red
and yellow marrow
Information then used to dose paint
IMRT plans minimizing red marrow
irradiation
Loren Mell MD
UC San Diego
ASCO Young Investigator
Award
18. Image-Guided Target Delineation
Brachytherapy
Growing interest in using imaging to
break away from Point A
Most attention on MRI
Radiother Oncol (2006)
19. PET-Guided Brachytherapy
Malyapa
Red Journal (2002)
Intravenous FDG
+ FDG inserted into
tandem and ovoids
20. Used to conform
dose to shape of the
cervix and uterus
Excellent correlation
with MRI
21. Image-Guided
Treatment
Delivery
Cancer Center Corridor
23. Rationale
All 3 issues are a problem for IMRT
Rapid dose gradients very unforgiving
Inaccurate setup, organ motion and
regression all may lead to underdosage
of the tumor and overdosage of the
normal tissues
IGRT has the potential to overcome all
three problems
25. Ultrasound-Based IGRT
Cervical Cancer
Little data
Surprising given popularity in prostate cancer
But useful for difficult implants
Bad
Good
26. Video-Based IGRT
Cervical Cancer
No data
Appealing given ability to monitor intra-fraction
patient position in real-time without x-rays
Clinical trial planned at UCSD
Align RT system
Ceiling-mounted cameras
Real-time 3D surface image
Popular in breast and lung cancer
27. Planar-Based IGRT
Cervical Cancer
Most studied IGRT approach in cervical cancer
Long history using electronic portal imaging
devices (EPID) to monitor patient setup
MV image of bony anatomy or implanted
markers
Antonuk (2002)
28. EPID-Based IGRT
Implanted Fiducials on Cervix
Kaatee (2002)
10 cervical cancer pts
Radiopaque tantalum markers
on cervix
Used to track cervix position
Image quality good-excellent
½ lost before end of RT
29. Red J (2000)
14 gynecology pts
On-line EPID IGRT
Based on boney landmarks
Action level > 4 mm
57% re-positioned
Average time ~ 3 minutes
Acquisition and adjustment
↓PTV margins to 5 mm
30. Real-Time Tumor Tracking
(RTRT)
Four sets of diagnostic x-ray
tubes and imagers
1.5 MHU x-ray tube and a fixed
floor-mounted collimator
Corresponding ceiling-mounted
imager
Mitsubishi Electronics Co Ltd, Tokyo, Japan
http://global.mitsubishielectric.com/
31. RTRT System
During treatment,
2 of the 4 x-ray systems
Track an implanted marker
Using motion tracking software
Tracking is continuous
If the marker coordinates are
within a permitted distance,
the beam is triggered on
Marker position calculated
0.03 seconds
Harada (2002)
32. Green Journal (2004)
10 gynecology patients with implanted fiducials
Necessary CTV-PTV margin using real-time RTRT
tracking:
6.9 mm (right-left), 6.7 mm (sup-inf), 8.3 mm (ant-post)
No data using other popular planar systems
(CyberKnife, Novalis)
33. Planar-IGRT Systems
Several vendors have mounted kV sources
on gantry opposite amorphous silicon (aSi)
flat panel detectors
Capable of generating high quality kV planar
images
Better image quality and less dose than EPID
Emerging data using both approaches
None focused solely on gynecology patients
34. Commercial Gantry-Mounted Systems
Planar IGRT
Varian On-Board Imaging (OBI)
www.varian.com
EPID aSI Detector
kV Source
Elekta Synergy
www.elekta.com
35. Planar kV Commercial
Systems
Varian OBI planar-IGRT
system
On-line patient setup correction
based on bony landmarks
Variety of tumor sites including
gynecology
Feasible
Entire process < 1 additional
minute
37. Process Flow
Planar IGRT (Gynecology-Pelvis)
Day 1
MD and RTTs meet at console
Discuss anatomy, special issues, etc.
Day 2 thru Completion
Other shifts
All shifts ≤ 1 mm LR shift > 15 mm
SI or AP shift > 15 mm
Any concerns
Make all shifts
Make no shifts
Call MD and treat
and treat
38. Planar kV Commercial Systems
Offer the potential to track
Implanted fiducials
Analogous to on-line
techniques popularized in
prostate cancer
Potentially useful to deliver
a high dose conformal
boost in patients unable to
receive brachytherapy
39. Volumetric-Based IGRT
Interest is now turning to volumetric
IGRT
Several vendors offer volumetric
solutions using the MV treatment beam
Tomotherapy, Siemens
Others generate kV cone-beam CT
(CBCT) scans by reconstructing
multiple planar kV images
Varian, Elekta
40. Volumetric-IGRT
High quality kV CBCT
scans can be
produced
Useful now to monitor
target coverage
In future, opens door
to adaptive RT
41. On-Line Planar, Off-line Volumetric IGRT
Cervical Cancer
Planar KV Imaging
Align boney anatomy
(↓CTV-PTV margins around Nodes
Generous margins around cervix)
↓
Video Imaging
Monitor Patient Position during Tx
↓
Volumetric Imaging
Off-line monitoring of target Coverage
Adjust margins if necessary
42. Day 2
Day 1
Day 2
Day 1
Day 3 Day 4
Day 4
Day 3
Day 5
Day 5
43. Day 2
Day 1
Day 1 Day 2
Day 3
Day 4
Day 3 Day 4
Day 5
95%
90%
Day 5
85%
80%
44. Volumetric-based IGRT
Cervical Cancer
Off-line monitoring of target coverage is
very useful
Particularly important if modest margins
are used around the cervix and fundus
We used 1.7 cm margins
Modifications are still common to ensure
coverage
45. CBCT Cervical Cancer Study
Margin % Fx Volume Location
(mm) CTV Missed Missed Fundus Cervix
0 100% 45.3 cc 100% 95.2%
3 98.7% 24.8 cc 89.0% 79.5%
5 95.4% 20.3 cc 83.6% 65.1%
7 87.2% 13.9 cc 71.2% 50.0%
10 59.3% 9.3 cc 54.0% 35.6%
15 32.1% 4.0 cc 24.0% 18.5%
20 19.3% 1.7 cc 11.6% 10.9%
25 14.0% 0.7 cc 7.5% 6.9%
30 6.7% 0.3 cc 4.1% 0.7%
46. Image-Guided
Adaptive RT
Aerial View, Inner Garden
and Cafe
47. Adaptive IGRT
Tumors shrink
And often quite quickly with
chemotherapy plus RT
Shrinkage is a double-edged sword
Reduces the Reduces the
chance of a conformity of the
geographic miss original plan
48.
49. Tumor Response
Many investigators have quantified the rate of
response in cervical cancers
University of Utah used physical exam
measurements and found by 30.8 Gy tumors
reduced by 50%
MD Anderson used weekly conventional CT
and noted a mean reduction of 64%
Others have used IMRT to better calculate
tumor regression
Lee et al. Red Journal 2005;58:625
Beadle et al. ASTRO 2006
Mayr et al. Am J Roentgenol 2006;187:65
Van de Bunt et al. Red Journal 2006;64:189
50. 14 cervical cancer patients
MRI prior to RT and after 30 Gy external beam
GTV decreased (on average) by 46%
Decrements in CTV and PTV were 18% and 9%
51. Does Re-Planning Help?
Re-optimizing the IMRT plan at 30 Gy
improved the sparing of the rectum
Average rectal volume receiving ≥ 95%
of the prescription dose
75 cc (range, 20-145 cc) (No Re-planning)
67 cc (range, 15-106 cc) (Re-planning)
P = 0.009
Improved bowel sparing seen in women
with bulky (> 30 cc) tumors
52. Does Re-Planning Help?
Currently analyzing a large dataset of
daily CBCT in cervical cancer patients
undergoing IMRT and chemotherapy
Daily imaging data allows us to not only
ask whether re-planning helps, but the
optimal frequency and timing of re-
planning
53. Adaptive IGRT
Many technical obstacles stand in the
way of adaptive IGRT, particularly if
performed on-line
New software tools: image deformation
and automated segmentation
Better quality CBCT imaging
New rapid, accurate QA approaches
54. Adaptive IGRT
Once technical obstacles are overcome,
numerous clinical questions remain
Does adaptive IGRT help? Does it hurt?
Should it be performed on-line or off-line?
How often should it be done? Weekly?
Daily?
Such questions can only be addressed
in carefully designed clinical trials
56. Adaptive IGRT
Necessary tools being developed at
UCSD in collaboration with the San
Diego Super-Computer Center and
Varian Medical Systems
57. On-Line Setup, Off-Line Adapt On-Line Setup, On-Line Adapt
Setup to Marks
On-Line
Planar IGRT
On-Line
Deliver Treatment CBCT
Real-time Video
IGRT
Re-plan if necessary
Off-Line Deliver Treatment
Analysis Real-time Video
Re-Plan as IGRT
needed
58. “Re-Plan If Necessary”
Need to decide on the table within
minutes!
Not an simple task
Could involve target and normal tissue
delineation, re-planning and evaluating
potential benefit
A more elegant solution may be to use
the CBCT image itself
Analyzed using Machine Learning
61. On-Line Adaptation
Deform simulation CT anatomy into all
potential anatomical changes
Generate 1000+ IMRT plans using
supercomputer computational power
Image patient on the table each day and
select most similar plan
Treat with new plan
62. Daily Re-Planning
High speed computer processing is
essential
Need to move from sequential
processing to parallel processing
Never been applied to radiation oncology