Types Of Treatment Techniques Research Articles

Survival Outcomes in Different Sino-nasal Malignancies: An Institutional Review

Objective: The purpose of this review is to comprehend the treatment outcome of different PNS cancer histologies and their survival. Materials and Procedures: A review of our institutional database from January 2010 to December 2022 included 122 sinonasal cancer patients. After exclusions, 84 patients whose data sets were complete underwent analysis. Overall survival (OS), loco-regional failure-free survival (LRFS), and distant metastases-free survival (DMFS) were the measured endpoints. Results: With a median follow-up time of 26 months, there was no correlation detected between histological type and OS, LRFS, or DMFS. It was discovered that the type of treatment technique was substantially related to LRFS. Surgery plus adjuvant radiation and/or chemotherapy had a minor tendency to be significant in terms of OS, with a median OS of 56 months (95% CI: 38.6–73.3). Conclusions: It showed that the use of different treatment modalities had an impact on LRFS, while the type of histology did not correlate with the effectiveness of the treatment.

Comparison of the Direct Power Consumption for Different Linac Treatment Parameters in External Beam Radiation Therapy

The negative impact of climate change on the environment has led to increasing concern around the world. Relatively little is known about the contribution of radiation oncology systems to carbon emissions. This study measures the energy utilization of Linac-based EBRT for different treatment parameters and techniques, which was then converted to power use (kWh) and ultimately a carbon footprint of various photon treatment approaches. A Varian TrueBeam was evaluated. The direct power consumption was measured using a Fluke 1736 Power Logger, recorded in one-second intervals for one week. Different photon and electron beam energies, dose rates, treatment techniques (3D, IMRT, gated), and imaging types (kV, MV) were evaluated. Clinical treatment plans were reviewed, and average treatment times used to determine kWh. IRB approval was obtained. The Greenhouse Gas Equivalencies Calculator was used to determine kg of CO2. Power draw for 6 MV, 10 MV, and 18 MV at a rep rate of 600 MU/min was 31.6, 32.0, and 27.5 kW, respectively. The power draw for end of range dose rates for 6 MV (60, 600), 6 FFF (400, 1400), 10 FFF (400, 2400), and 6 MeV (100, 1000) were (22.2, 31.6 kW), (23.7, 31.6 kW), (19.6, 32.1 kW), and (22.6, 23.6 kW), respectively. 6 MV open 2D fields, modulated IMRT fields, and gated/beam hold fields had similar power draw at 31.6, 31.7, and 31.9 kW, respectively. Portal MV imaging with 2.5 MV beam was 32.5 kW, while CBCT and kV/kV imaging was ∼11 kW and not distinguishable from baseline power fluctuations. A total of 191 delivered treatment plans were reviewed. Electron plans (n = 8) treatment time was on average 29 sec (16 sec STDEV) per fraction and 635 sec (185 sec STDEV) per course, 2D/3D plans (n = 63) were 77 sec (32 sec STDEV) and 1004 sec (1002 sec STDEV), and IMRT plans (n = 120) were 182 sec (60 sec STDEV) and 5351 sec (2401 sec STDEV), respectively. The kWh per treatment for electron, 2D/3D, and IMRT plans were 0.19, 0.68, and 1.6 kWh, respectively. The CO2 equivalent for electrons, 2D/3D, and IMRT techniques are 0.08, 0.29, and 0.7 kg. There was some variability in the power draw for different energies and different dose rates but was relatively stable around 32 kW. Power consumption for clinical therapy is a result of kW power draw multiplied by duration of beam delivery, which for our patients varied significantly as a function of technique and number of fractions delivered. Reduction in radiation oncology carbon footprint will likely be driven more by number of fractions and type of treatment technique, and length of patient commute, rather than beam energy and dose rate selection.

In-vivo dosimetry in Total Skin Electron Therapy: Literature review

AbstractAim:Total Skin Electron Therapy (TSET) is a specialised radiotherapy technique to treat cutaneous T-cell lymphomas. The purpose of this article is to review different in-vivo dosimetry techniques and to identify further research direction in TSETMaterials and methods:Studies focused on in-vivo dosimetry in TSET were included. Studies based on absolute dosimetry in TSET were excluded and no restriction was applied regarding the type of treatment technique and the type of dosimeter.Result:From the review of articles, we have found that obesity index and patient position during treatment plays a major role in underdose or overdose in TSET. Many studies favour individualised boost dose to patients. The analysis showed that thermoluminescent dosimeters are the most widely used dosimeters in TSET, and time-consuming is the only drawback in the use of dosimetry.Conclusion:Study showed that the practice of using in-vivo dosimetry would be better way to treat TSET by ensuring accuracy of dose delivery to the patients. Further, only limited studies are available for dosimetry with radiochromic films. With this observation, we have started exploring the use of radiochromic film in our TSET dosimetry, and the results can be analysed to standardise the technique in future.

Interventional radiology treatments for iatrogenic severe bleeding during percutaneous coronary interventions.

PurposeInterventional cardiology and interventional radiology are separate medical disciplines in which intra-arterial contrast media are used. Interventional cardiology has resigned from many types of treatment techniques that are now used and developed in the field of interventional radiology. In the event of iatrogenic bleeding during coronary interventions, there is an urgent need to use safe and efficient rescue procedures that are as efficient as cardiosurgery but use simpler treatment options. Serious perforations require immediate endovascular interventions. Medical history may reveal risk factors for artery perforation. Medicines, location of artery perforation, and extent of bleeding are directly associated with the prognosis. Most often, arterial perforations are due to inappropriate wire manipulation or use of oversized balloons or cutting balloons. Prolonged, artery-occluding balloon inflation, covered stent implantation, and embolisation with different agents are among the available treatment options for artery ruptures.Material and methodsA retrospective analysis was carried out among selected patients with iatrogenic vascular complications during procedures involving either coronary or non-coronary arteries.ResultsOnly representative cases were selected and presented in the patient subsection.ConclusionsArtery perforation during cardiac catheterisation can lead to dire consequences. To manage this complication, clinicians need pre-established procedures, adequate resources, and knowledge. Interventional radiology can be used as a salvage therapy in such cases.

Optimization of a general-purpose, actively scanned proton beamline for ocular treatments: Geant4 simulations.

The Italian National Center for Hadrontherapy (CNAO, Centro Nazionale di Adroterapia Oncologica), a synchrotron‐based hospital facility, started the treatment of patients within selected clinical trials in late 2011 and 2012 with actively scanned proton and carbon ion beams, respectively. The activation of a new clinical protocol for the irradiation of uveal melanoma using the existing general‐purpose proton beamline is foreseen for late 2014. Beam characteristics and patient treatment setup need to be tuned to meet the specific requirements for such a type of treatment technique. The aim of this study is to optimize the CNAO transport beamline by adding passive components and minimizing air gap to achieve the optimal conditions for ocular tumor irradiation. The CNAO setup with the active and passive components along the transport beamline, as well as a human eye‐modeled detector also including a realistic target volume, were simulated using the Monte Carlo Geant4 toolkit. The strong reduction of the air gap between the nozzle and patient skin, as well as the insertion of a range shifter plus a patient‐specific brass collimator at a short distance from the eye, were found to be effective tools to be implemented. In perspective, this simulation toolkit could also be used as a benchmark for future developments and testing purposes on commercial treatment planning systems.PACS numbers: 21.30Fe, 24.10.Lx, 29.20.dk, 29.27.Eg, 29.85.Fj

Impact of Very Rapid Irradiation on Clonogenic Survival

probability of tumors, organ toxicity and overall prognosis of the SIB and SqIB treatments of head and neck cancer using the selective radiobiological models. Similar agreements were also reported in the SqIB treatments of head and neck cancer. A large cohort group of study is warranted to increase to power of observations to these models which will strengthen our conclusions. That can help to take preventive measures for the critical organs in such types of treatments, as well as in ranking different types of treatment techniques. Author Disclosure: A. Pyakuryal: None. S. Pandit: None. G. Narayanasamy: None. S. Jang: None. S. Lee: None. T.T. Sio: None.

Sci-Fri PM: Delivery - 02: Position-Probability-Sampled Monte Carlo Calculation of VMAT, 3DCRT, Step-Shoot IMRT and Helical Tomotherapy Dose Distributions Using BEAMnrc / DOSXYZnrc

The commercial release of volumetric modulated arc therapy techniques using a conventional linear accelerator and the growing number of helical tomotherapy users has triggered renewed interest in both MC dose verification methods and tools for doing treatment planning studies and exploring the impact of machine tolerance and patient motion on dose distributions. We report here the development of a method for performing complete position-probability-sampled Monte Carlo dose calculation using the BEAMnrc / DOSXYZnrc code. The method includes full accelerator head simulation and a realistic representation of continuous motion, with no resort to discretization approximations or analytical procedure. Accelerator head models were defined and validated against measurements for a conventional accelerator (Elekta Synergy ™) and a helical tomotherapy accelerator (TomoTherapy Hi-Art®). The method functionality was tested by comparing simulated and treatment planning dose distributions for four types of treatment techniques: 3D-conformal, step-shoot intensity modulated radiation therapy, helical tomotherapy and volumetric modulated arc therapy. Absolute dose agreement for static fields between MC and measurements is within 2% / 2mm. Absolute dose agreement between MC and TPS was determined to be 3% / 3mm. The method simplifies the simulation process, improves the dose calculation accuracy and involves a minimal change in computation time.

MO-A-T-6E-01: Acceptance Testing and Systematic QA

Acceptance testing and systematic QA of planning and delivery of IMRT is different compared to corresponding procedures for other conformal RT techniques. The special hard‐ and software necessary for the planning and delivery of IMRT is rather complex while the vendors continuously offer improvements of their systems. With respect to the acceptance testing of IMRT delivery systems, high demands are made upon leaf position accuracy, linac performance for small MU delivery, the control system for leaf movement, and leaf speed stability. The treatment planning system requires a thorough insight in the factors determining the accuracy of the dose calculation such as the transmission and leakage through the leaves, the tongue‐and‐groove effect, the description of the penumbra and the dose outside the high‐dose region. Furthermore the accuracy of the calculation of the dose in small fields and the effects of grid size on dose calculation and display should be known. Also the uncertainties in volume determinations and dose‐volume histograms have to be assessed. A number of these tests have to be repeated if considerable modifications in hard‐ or software occur, for instance if a new sequencer is implemented. The routine clinical use of this complex treatment modality requires an efficient QA program, which should include (daily, weekly, monthly….) tests for the safe delivery of complex 3‐D dose distributions. Specific tests for individual patient treatments should also be designed, which may include patient‐specific measurements and/or an independent dose calculation. Programs for both acceptance testing and systematic QA should be adapted to the complexity of the IMRT techniques applied in a specific center, as well as to the resources available. Finally it can be noted that contrary to the situation in the US,IMRT in Europe was until recently only applied in a relatively small number of, mainly academic, institutions. The reason for this difference in widespread implementation was that in EuropeIMRT was considered more as an experimental type of treatment technique requiring considerable resources. In recent years both the hard‐ and software became more mature, while also more experience with respect to QA of IMRT became available. As a consequence many more institutions, also smaller and busy clinics, started in Europe with IMRT, facing the problem of performing a comprehensive QA program in routine clinical practice. In various European countries (e.g., Spain, Italy and the UK) documents for the guidance for the clinical implementation of IMRT are now in preparation. In these reports recommendations for both physical and clinical aspects of QA of IMRT are provided, while ESTRO is preparing a report dedicated to the verification of IMRT. Educational Objectives: 1. To understand the special issues related to acceptance testing and systematic QA of planning and delivery of IMRT compared to those required for other conformal RT techniques. 2. To understand the various aspects of design and implementation of a program for acceptance testing and systematic QA of planning and delivery of IMRT.

Effect of set-up uncertainties on the dose distribution in the match region of supraclavicular and tangential breast fields

Background: The objective of this paper is to illustrate the effect of a gap of 5 mm, an overlap of 5 mm and a perfect match on the dose distribution across the junction of tangential breast fields and adjacent supraclavicular and axillary fields. Materials and methods: For this purpose film dosimetry was applied to measure relative dose distributions in two sagittal planes in an anthropomorphic breast phantom having cork lungs, simulating a radiation therapy treatment of the breast and adjacent supraclavicular lymph nodes. Two different treatment techniques, an SSD match technique and a geometrically exact isocentric match technique, as routinely applied in the two institutes were examined. The three-dimensional treatment planning system of each institute was used to calculate the dose distribution in the match region of the supraclavicular fields and the two opposing tangential fields. The measured and calculated dose distributions were evaluated and compared along lines in two sagittal planes from the supraclavicular fields down to the tangential fields crossing the match planes. These dose distributions in the match region were extremely dependent on the set-up of the fields. Results: Although the reproducibility of the film measurements was within 2%, it became clear that the set-up of the fields to achieve a gap of 5 mm, a perfect match or an overlap of 5 mm required a lot of attention, even when using a phantom. Conclusions: It can be concluded that in clinical practice, these set-up difficulties do influence the dose distribution in the match region much more than the systematic uncertainties in the dose calculation algorithms of the treatment planning systems and the type of treatment technique.

An Examination of Some Trends in Child Behavior Therapy

The purpose of the present study was to examine some trends in child behavior therapy over the past 12 years and to suggest some future directions. Four behavioral journals that have been in existence since at least 1970 were examined for type of behavior treated and type of treatment technique utilized. Beginning with 1970 every other year of each journal was examined and 410 articles dealing with the treatment of children were identified. There was no systematic trend across years in the number of articles published in this area. Furthermore, only a few trends across years were noted for behaviors treated or treatment technique utilized. Negative behaviors, particularly acting out ones, had been targeted for treatment most often. Consequences, particularly of a positive nature, had been utilized most often as the treatment technique of choice. The need to expand our models by treating new behaviors and utilizing new techniques was discussed.

Roentgen irradiation at 200 kV of neoplasms of the nasopharynx. Technique and dose distribution.

hlalignant tumours of the nasopharynx have usually been treated by conventional roentgen therapy. In recent years y-radiation from 6oCo sources and high energy roentgen rays from 35 MeV betatrons have also been employed; an attempt was made by SNELLING in 1954 to estimate the dose distribution for some different types of treatment techniques. This paper presents an analysis of the dose distribution in the nasopharynx and adjacent structures obtained by roentgen irradiation at 200 kV with a 4-field technique in the treatment of tumours limited to the nasopharynx. Technique. A sketch is first made of the contour of the face at the level of the nasopharynx and a lateral roentgenogram is obtained of the skull. The enlargement of the roentgenogram in the sagittal plane can be determined by means of a measuring stick fixed on the forehead and nose of the patient. The true depth of the nasopharynx and the site of the tumour are established and transferred to the previously drawn sketch.