View All Items

Title: Comparison study between BrainLab and Eclipse for small cancer lesions.
Creator: Doozan, Brian, Leventouri, Theodora, Pella, Silvia, Graduate College
Abstract/Description: There are many available options today for treating small lesion cancer cells. Two of the most used options are the planning systems BrainLab and Eclipse. The main difference between the two is the algorithms that are used to calculate the dose distribution of external beam radiation therapy. BrainLab offers a Monte Carlo based algorithm while Eclipse utilizes the Anisotropic Analytical Algorithm. An investigative study on the quality of the planning system is done for cases in lung, head and...
Show moreThere are many available options today for treating small lesion cancer cells. Two of the most used options are the planning systems BrainLab and Eclipse. The main difference between the two is the algorithms that are used to calculate the dose distribution of external beam radiation therapy. BrainLab offers a Monte Carlo based algorithm while Eclipse utilizes the Anisotropic Analytical Algorithm. An investigative study on the quality of the planning system is done for cases in lung, head and neck and prostate. In particular, lung cases are highly heterogeneous which can lead to problems in the calculation. The ability to be able to plan on the best system for individual cases can lead to better and more consistent treatments for cancer patients.
Show less
Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00005812
Format: Document (PDF)

Title: Dosimetric Consequences From Minimal Displacements In Abpi With Savi Applicators.
Creator: Chandrasekara, Shereen, Pella, Silvia, Leventouri, Theodora, Graduate College
Abstract/Description: Purpose: To highlight the importance of provide proper solid immobilization initially and in every treatment in ABPI with brachytherapy. Materials and Methods: 100 patients receiving brachytherapy treatments in ABPI using the Savi applicators were considered for the study. The CT scans used in the initial plan was compared with every scan obtained before each treatment. Each of these scans were exported in the planning system and registered with the initial plan. Dosimetric evaluations were...
Show morePurpose: To highlight the importance of provide proper solid immobilization initially and in every treatment in ABPI with brachytherapy. Materials and Methods: 100 patients receiving brachytherapy treatments in ABPI using the Savi applicators were considered for the study. The CT scans used in the initial plan was compared with every scan obtained before each treatment. Each of these scans were exported in the planning system and registered with the initial plan. Dosimetric evaluations were performed with their consequences to the ribs and the skin surface. Results: Making the dosimetric comparison for the critical points on the ribs and skin due to very small changes in the interfractionation position revealed dramatic differences in the maximum dose to these critical organs. The cavity's volume manifested changes between fractions as well as the distances to the two critical organs. Therefore the maximum dose manifested variance between 10 and 32 in both of the sites Conclusions: This study demonstrates that using CT scan before each treatment will minimize the risk of delivering undesired high doses to the critical organs. This reveals the urgent need of increasing and improving the immobilization methods when treating ABPI with Savi. In 30 of the cases re-planning was necessary between fractions therefore we conclude that in each case the treatment and planning teams must be prepared for re-plan as needed.
Show less
Date Issued: 2015
PURL: http://purl.flvc.org/fau/fd/FA00005872
Format: Document (PDF)

Title: Motion challenges in high dose rate (HDR) brachytherapy.
Creator: Curley, Casey Michael, Pella, Silvia, Leventouri, Theodora, Graduate College
Date Issued: 2013-04-12
PURL: http://purl.flvc.org/fcla/dt/3361287
Subject Headings: Brachytherapy, Leipzig, Immobilization
Format: Document (PDF)

Title: Should we use RapidArc (VMAT) for breast radiotherapy? A Dosimetric comparison of IMRT versus VMAT optimization.
Creator: Moshiri Sedeh, Nader, Pella, Silvia, Leventouri, Theodora, Graduate College
Abstract/Description: Purpose: The purpose of this study is to compare the dose-volumetric results of intensity modulated radiation therapy (IMRT) with RapidArc (RA Varian Medical Systems, Palo Alto, CA) for whole breast irradiation. Methods: 25 patients previously treated for whole left breast (either RapidArc plan or IMRT) were the subjects of this planning study. Eclipse v 11.0.47 was used to make all retrospective plans using the same contours, energy, machine and normalization. Prescription dose to the...
Show morePurpose: The purpose of this study is to compare the dose-volumetric results of intensity modulated radiation therapy (IMRT) with RapidArc (RA Varian Medical Systems, Palo Alto, CA) for whole breast irradiation. Methods: 25 patients previously treated for whole left breast (either RapidArc plan or IMRT) were the subjects of this planning study. Eclipse v 11.0.47 was used to make all retrospective plans using the same contours, energy, machine and normalization. Prescription dose to the planning target volume was 5000 Gy in 25 fractions. All plans were normalized such that 100% covered 95% of planning target volume (PTV). Results: V10, V20 and Dmean Gy of left lung significantly differed between the two plans (p-value <0.0001, =0.0473 and <0.0001 respectively), but V30 Gy did not (p-value 0.463). V25, D33 and Dmean Gy of heart significantly differed between the two plans (p-value =0.034, <0.0001 and 0.01 respectively), but V10 Gy did not (p-value 0.058). V5 of both right breast and right lung significantly differed between the two plans (p-value <0.0007 and =0.0112, respectively). Also Dmean of both right breast and right lung significantly differed between the two plans (p-value <0.0001 for both). The mean conformity index did not significantly differ, p-value 0.142. There was a significant difference between the mean MUs of the two plans as well, p-value <0.0001.
Show less
Date Issued: 2015
PURL: http://purl.flvc.org/fau/fd/FA00005901
Format: Document (PDF)

Title: Investigation of Dose Variation with Minor Displacement in High Dose Radiation Brachytherapy.
Creator: Hyvärinen, Mikko, Curley, Casey Michael, Long, Samanthia, Graduate College, Herrera, Ramses, Dumitru, Nicolae, Pella, Silvia
Abstract/Description: High dose rate HDR brachytherapy dose distribution is highly localized and has a very sharp dose fall-off. Thus one of the most important part of the treatment is the localization and immobilization of the applicator from the implantation to the setup verification to the treatment delivery. The smallest motions of the patient can induce a small rotation, tilt, or translational movement of the applicator that can convert into miss of a significant part of the tumor or to over irradiating a...
Show moreHigh dose rate HDR brachytherapy dose distribution is highly localized and has a very sharp dose fall-off. Thus one of the most important part of the treatment is the localization and immobilization of the applicator from the implantation to the setup verification to the treatment delivery. The smallest motions of the patient can induce a small rotation, tilt, or translational movement of the applicator that can convert into miss of a significant part of the tumor or to over irradiating a nearby critical organ. The purpose of this study is to revise most of the HDR types of treatments with their applicators and their localization challenges. Since every millimeter of misplacement counts the study will look into the necessity of increasing the immobilization for several types of applicators. This study data indicates that an improvement of the immobilization devices for HDR is absolutely necessary. Better applicator fixation devices are required too. Developing new immobilization devices for all the applicators is recommended.
Show less
Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00005824
Format: Document (PDF)

Title: COMMISSIONING AND ACCEPTANCE TESTING OF A TRUEBEAM LINEAR ACCELERATOR.
Creator: Dumitru, Nicolae, Pella, Silvia, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Due to the difficulty of a complex commissioning technique for a multi energetic, multi-modality linear accelerator, I perform all the commissioning and acceptance testing for a TrueBeam linear accelerator with 4 megavoltage (MV) energies of which 2 are flattening filter-free (FFF) and 6 electron energies varying from 6 MeV to 20 MeV. A 2 dimensional (2D) water tank was used for scanning all the required field sizes for all the energies. The one dimensional (1D) water tank was used to collect...
Show moreDue to the difficulty of a complex commissioning technique for a multi energetic, multi-modality linear accelerator, I perform all the commissioning and acceptance testing for a TrueBeam linear accelerator with 4 megavoltage (MV) energies of which 2 are flattening filter-free (FFF) and 6 electron energies varying from 6 MeV to 20 MeV. A 2 dimensional (2D) water tank was used for scanning all the required field sizes for all the energies. The one dimensional (1D) water tank was used to collect all the output factors for all the photon fields sizes small to medium electron field sizes. For the large electron fields sizes, we had to use the 2D water tank. All the collected data was converted into a file type accepted by the planning system (Eclipse) and subsequently imported there. Treatment plans were generated using multiple forms of planning to verify the viability and quality of the beam data commissioned.
Show less
Date Issued: 2019
PURL: http://purl.flvc.org/fau/fd/FA00013301
Subject Headings: Linear accelerators, Cancer--Treatment, Radiation dosimetry
Format: Document (PDF)

Title: Empirical beam angle optimization for lung cancer intensity modulated radiation therapy.
Creator: Doozan, Brian, Pella, Silvia, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Empirical methods of beam angle optimization (BAO) are tested against the BAO that is currently employed in Eclipse treatment planning software. Creating an improved BAO can decrease the amount of time a dosimetrist spends on making a treatment plan, improve the treatment quality and enhance the tools an inexperienced dosimetrist can use to develop planning techniques. Using empirical data created by experienced dosimetrists from 69 patients treated for lung cancer, the most frequently used...
Show moreEmpirical methods of beam angle optimization (BAO) are tested against the BAO that is currently employed in Eclipse treatment planning software. Creating an improved BAO can decrease the amount of time a dosimetrist spends on making a treatment plan, improve the treatment quality and enhance the tools an inexperienced dosimetrist can use to develop planning techniques. Using empirical data created by experienced dosimetrists from 69 patients treated for lung cancer, the most frequently used gantry angles were applied to four different regions in each lung to gather an optimal set of fields that could be used to treat future lung cancer patients. This method, given the moniker FAU BAO, is compared in 7 plans created with the Eclipse BAO choosing 5 fields and 9 fields. The results show that the conformality index improved by 30% or 3% when using the 5 and 9 fields. The conformation number was better by 12% from the 5 fields and 9% from the 9 fields. The organs at risk (OAR) were overall more protected to produce fewer nonstochastic effects from the radiation treatment with the FAU BAO.
Show less
Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004280, http://purl.flvc.org/fau/fd/FA00004280
Subject Headings: Cancer -- Radiotherapy, Image guided radiation therapy, Lung cancer -- Treatment, Medical physics, Medical radiology -- Data processing, Medicine -- Mathematical models
Format: Document (PDF)

Title: A Dosimetric Comparison of 3D-CRT, IMRT, and SAVI HDR via NTCP/TCP and DVH Analysis of Critical Organs for Breast Cancer.
Creator: Wisnoskie, Sarah, Pella, Silvia, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Accelerated Partial Breast Irradiation (APBI) is a common treatment of breast cancer with many modalities including 3D Conformal Radiation Therapy (3D-CRT), Intensity Modulated Radiation Therapy (IMRT), and High Dose Rate Brachytherapy (HDR). In this research, a retrospective analysis of patient’s data was performed to analyze the NTCP/TCP (Normal Tissue Complication Probability/Tumor Control Probability) and Dose Volume Histogram (DVH) parameters for HDR with SAVI, 3D, and IMRT and compare...
Show moreAccelerated Partial Breast Irradiation (APBI) is a common treatment of breast cancer with many modalities including 3D Conformal Radiation Therapy (3D-CRT), Intensity Modulated Radiation Therapy (IMRT), and High Dose Rate Brachytherapy (HDR). In this research, a retrospective analysis of patient’s data was performed to analyze the NTCP/TCP (Normal Tissue Complication Probability/Tumor Control Probability) and Dose Volume Histogram (DVH) parameters for HDR with SAVI, 3D, and IMRT and compare them focusing on critical organs such as the heart, ipsilateral lung, chest wall, ribs, and skin. TCP was 90.275%, 55.948%, and 53.369% for HDR, 3D, and IMRT respectively. The ribs were the most sensitive critical organ for all 3 modalities with a mean NTCP of 8%, 15%, and 8% for HDR, 3D, and IMRT respectively. DVH analysis showed HDR spares critical organs more than EBRT except for 2 patients receiving high doses to the ribs and chest wall.
Show less
Date Issued: 2019
PURL: http://purl.flvc.org/fau/fd/FA00013281
Subject Headings: Radiation dosimetry--Evaluation, Breast--Cancer--Treatment, Organs, Tissues--Effect of radiation on
Format: Document (PDF)

Title: New method of collecting output factors for commissioming linear accelerators with special emphasis on small fields and intensity modualted readiation therapy.
Creator: Smith, Cindy, Pella, Silvia, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Common methods for commissioning linear accelerators often neglect beam data for small fields. Examining the methods of beam data collection and modeling for commissioning linear accelerators revealed little to no discussion of the protocols for fields smaller than 4 cm x 4 cm. This leads to decreased confidence levels in the dose calculations and associated monitor units (MUs) for Intensity Modulated Radiation Therapy (IMRT). The parameters of commissioning the Novalis linear accelerator ...
Show moreCommon methods for commissioning linear accelerators often neglect beam data for small fields. Examining the methods of beam data collection and modeling for commissioning linear accelerators revealed little to no discussion of the protocols for fields smaller than 4 cm x 4 cm. This leads to decreased confidence levels in the dose calculations and associated monitor units (MUs) for Intensity Modulated Radiation Therapy (IMRT). The parameters of commissioning the Novalis linear accelerator (linac) on the Eclipse Treatment Planning System (TPS) led to the study of challenges collecting data for very small fields. The focus of this thesis is the examination of the protocols for output factor collection and their impact on dose calculations by the TPS for IMRT treatment plans. Improving output factor collection methods, led to significant improvement in absolute dose calculations which correlated with the complexity of the plans.
Show less
Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004161
Subject Headings: Coherence (Nuclear physics), Linear accelerators in medicine, Medical physics, Nuclear medicine, Particle beams, Radiation -- Dosage, Radiotherapy -- Positioning
Format: Document (PDF)

Title: Validation of a Monte Carlo dose calculation algorithm for clinical electron beams in the presence of phantoms with complex heterogeneities.
Creator: Enright, Shayla Landfair, Pella, Silvia, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: The purpose of this thesis is to validate the Monte Carlo algorithm for electron radiotherapy in the Eclipse™ treatment planning system (TPS), and to compare the accuracy of the Electron Monte Carlo algorithm (eMC) to the Pencil Beam algorithm (PB) in Eclipse™. Dose distributions from GafChromic™ EBT3 film measurements were compared to dose distributions from eMC and PB treatment plans. Measurements were obtained with 6MeV, 9MeV, and 12MeV electron beams at various depths. A 1 cm thick solid...
Show moreThe purpose of this thesis is to validate the Monte Carlo algorithm for electron radiotherapy in the Eclipse™ treatment planning system (TPS), and to compare the accuracy of the Electron Monte Carlo algorithm (eMC) to the Pencil Beam algorithm (PB) in Eclipse™. Dose distributions from GafChromic™ EBT3 film measurements were compared to dose distributions from eMC and PB treatment plans. Measurements were obtained with 6MeV, 9MeV, and 12MeV electron beams at various depths. A 1 cm thick solid water template with holes for bone-like and lung-like plugs was used to create assorted configurations and heterogeneities. Dose distributions from eMC plans agreed better with the film measurements based on gamma analysis. Gamma values for eMC were between 83%-99%, whereas gamma values for PB treatment plans were as low as 38.66%. Our results show that using the eMC algorithm will improve dose accuracy in regions with heterogeneities and should be considered over PB.
Show less
Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004192
Subject Headings: Electron beams -- Therapeutic use, Image guided radiotherapy, Monte Carlo method, Proton beams -- Therapeutic use, Radiation dosimetry, Radiotherapy, High energy
Format: Document (PDF)

Title: The importance of immobilization and localization of gynecological applicators in high dose rate brachytherapy treatments.
Creator: Hyvärinen, Mikko, Pella, Silvia, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Intracavitary high dose rate (HDR) brachytherapy is a form of radiation therapy generally in which a post-surgical tissue margin is treated. The dose gradient of HDR brachytherapy is very steep, and thus small displacements of the applicator, even as small as 1 mm, could potentially cause significant variations of dose which could result in undesired side effects such as overdose of a critical organ. In this retrospective dosimetric study, the variation of dose due to various small range...
Show moreIntracavitary high dose rate (HDR) brachytherapy is a form of radiation therapy generally in which a post-surgical tissue margin is treated. The dose gradient of HDR brachytherapy is very steep, and thus small displacements of the applicator, even as small as 1 mm, could potentially cause significant variations of dose which could result in undesired side effects such as overdose of a critical organ. In this retrospective dosimetric study, the variation of dose due to various small range motions of gynecological applicators is investigated. The results show that the implementation of additional immobilization and localization devices along with other safety measures needs to be further investigated.
Show less
Date Issued: 2015
PURL: http://purl.flvc.org/fau/fd/FA00004446
Subject Headings: Artificial intelligence -- Medical applications, Cancer -- Intraoperative radiotherapy, Generative organs, Female -- Cancer -- Treatment, Imaging systems in medicine, Medical physics, Radiosotope brachytherapy
Format: Document (PDF)

Title: Measurements of output factors for small photon fields up to 10 cm x 10 cm.
Creator: Bacala, Angelina, Pella, Silvia, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Field output factors (OF) for photon beams from a 6 MV medical accelerator were measured using five different detectors in a scanning water phantom. The measurements were taken for square field sizes of integral widths ranging from 1 cm to 10 cm for two reference source-to-surface distances (SSD) and depths in water. For the diode detectors, square field widths as small as 2.5 mm were also studied. The photon beams were collimated by using either the jaws or the multileaf collimators....
Show moreField output factors (OF) for photon beams from a 6 MV medical accelerator were measured using five different detectors in a scanning water phantom. The measurements were taken for square field sizes of integral widths ranging from 1 cm to 10 cm for two reference source-to-surface distances (SSD) and depths in water. For the diode detectors, square field widths as small as 2.5 mm were also studied. The photon beams were collimated by using either the jaws or the multileaf collimators. Measured OFs are found to depend upon the field size, SSD, depth and also upon the type of beam collimation, size and type of detector used. For field sizes larger than 3 cm x 3 cm, the OF measurements agree to within 1% or less. The largest variation in OF occurs for jawsshaped field of size 1 cm x 1cm, where a difference of more than 18% is observed.
Show less
Date Issued: 2013
PURL: http://purl.flvc.org/fau/fd/FA0004003
Subject Headings: Integrated circuits, Photonics, Quantum electrodynamics, Quantum theory
Format: Document (PDF)

Title: Electronic structure calculations for alloys using the polymorphous coherent potential approximation.
Creator: Pella, Silvia, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: The Polymorphous Coherent Approximation (PCPA) plays the central role in this study. The PCPA represents an extension of the Coherent Potential Approximation (CPA) in the sense that it treats an alloy model in which all of the atoms are allowed to have distinct charges and potentials. It makes use of the supercells that contain hundreds of atoms. The Madelung potentials at all sites are calculated exactly. The present calculations demonstrate the advantages of the PCPA over the CPA in...
Show moreThe Polymorphous Coherent Approximation (PCPA) plays the central role in this study. The PCPA represents an extension of the Coherent Potential Approximation (CPA) in the sense that it treats an alloy model in which all of the atoms are allowed to have distinct charges and potentials. It makes use of the supercells that contain hundreds of atoms. The Madelung potentials at all sites are calculated exactly. The present calculations demonstrate the advantages of the PCPA over the CPA in explaining experiments that depend critically on the charge transfer in an alloy.
Show less
Date Issued: 2003
PURL: http://purl.flvc.org/fau/fd/FADT12029
Subject Headings: Physics, Condensed Matter
Format: Document (PDF)

Title: Radiation Induced Injury of Hepatocellular Carcinoma, IMRT vs SBRT.
Creator: Feghhi, Touhid, Pella, Silvia, Florida Atlantic University, Department of Physics, Charles E. Schmidt College of Science
Abstract/Description: Hepatocellular carcinoma is currently one of the most fatal cancers in the world. The routine treatment for this type of cancer consists of surgery, chemotherapy, and finally radiation therapy. Recent advancements in technology have enabled us to deliver highly conformed dose to planning target volume. Two of these methods are Intensity modulated Radiation Therapy (IMRT) and Stereotactic Body Radiation Therapy (SBRT). The difference between these two methods is that in the SBRT high radiation...
Show moreHepatocellular carcinoma is currently one of the most fatal cancers in the world. The routine treatment for this type of cancer consists of surgery, chemotherapy, and finally radiation therapy. Recent advancements in technology have enabled us to deliver highly conformed dose to planning target volume. Two of these methods are Intensity modulated Radiation Therapy (IMRT) and Stereotactic Body Radiation Therapy (SBRT). The difference between these two methods is that in the SBRT high radiation dose per fraction is delivered, but smaller number of fractions which renders better tumor control probability. However, better tumor control comes at the price of complications and radiation induced liver damage. In this work, we compare the outcome of radiation with regards to the probability of radiation damage to the liver after IMRT and SBRT. For this purpose, we analyzed 10 anonymized patients’ data with liver cancer, and we made two similar treatment plans for them. The difference in two plans is dose per fraction and total dose. After optimizing the treatments and calculating the dose volume histogram, we found the effective volume of the liver being irradiated. Finally, this effective volume and the corresponding dose were used to show that SBRT has the advantage of better tumor control probability at the cost of higher probability of complications.
Show less
Date Issued: 2022
PURL: http://purl.flvc.org/fau/fd/FA00014070
Subject Headings: Carcinoma, Hepatocellular, Radiotherapy--Adverse effects, Radiotherapy, Intensity-Modulated, Stereotactic Body Radiation Therapy
Format: Document (PDF)

Title: CONSISTENCY OF CT NUMBER AND ELECTRON DENSITY IN TREATMENT PLANNING SYSTEM VERSUS CT SCANNER, AND DOSIMETRIC CONSEQUENCES.
Creator: Hana, Evan Makdasy, Pella, Silvia, Leventouri, Theodora, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: The Computer Tomography (CT) scanned images are very important for the Treatment Planning System (TPS) to provide the electron density of the different types of tissues that the radiation penetrates in the path to the tumor to be treated. This electron density is converted to an attenuation coefficient, which varies with tissue for each structure and even varies by the tissue volume. The purpose of this research is to evaluate the CT numbers, and convert them into relative electron densities....
Show moreThe Computer Tomography (CT) scanned images are very important for the Treatment Planning System (TPS) to provide the electron density of the different types of tissues that the radiation penetrates in the path to the tumor to be treated. This electron density is converted to an attenuation coefficient, which varies with tissue for each structure and even varies by the tissue volume. The purpose of this research is to evaluate the CT numbers, and convert them into relative electron densities. Twenty-five patients’ data and CT numbers were evaluated in the CT scanner and in Eclipse and were converted into relative electron density and compared with each other. The differences between the relative electron density in the Eclipse was found to be from 0 up to 6% between tissue equivalent materials, the final result for all equivalent tissue materials was about 2%. For the patients’ data, the percentage difference of CT number versus electron density was found to be high for high relative electron density organs, namely the final average result for the spine was 8%, less for pelvis, and less for rib while for the other organs it was even less. The very lowest was 0.3% compared with 1% which is acceptable for clinical standards.
Show less
Date Issued: 2019
PURL: http://purl.flvc.org/fau/fd/FA00013315
Subject Headings: Tomography, X-Ray Computed, Electron density, Radiation dosimetry--Evaluation, Tomography Scanners, X-Ray Computed
Format: Document (PDF)

Title: Dosimetric and Radiobiological Comparison of Forward Tangent Intensity Modulated Radiation Therapy (FT-IMRT) and Volumetric Modulated Arc Therapy (VMAT) for Early Stage Whole Breast Cancer.
Creator: Moshiri Sedeh, Nader, Pella, Silvia, Leventouri, Theodora, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Intensity Modulated Radiation Therapy (IMRT) is a well-known type of external beam radiation therapy. The advancement in technology has had an inevitable influence in radiation oncology as well that has led to a newer and faster dose delivery technique called Volumetric Modulated Arc Therapy (VMAT). Since the presence of the VMAT modality in clinics in the late 2000, there have been many studies in order to compare the results of the VMAT modality with the current popular modality IMRT for...
Show moreIntensity Modulated Radiation Therapy (IMRT) is a well-known type of external beam radiation therapy. The advancement in technology has had an inevitable influence in radiation oncology as well that has led to a newer and faster dose delivery technique called Volumetric Modulated Arc Therapy (VMAT). Since the presence of the VMAT modality in clinics in the late 2000, there have been many studies in order to compare the results of the VMAT modality with the current popular modality IMRT for various tumor sites in the body such as brain, prostate, head and neck, cervix and anal carcinoma. This is the first study to compare VMAT with IMRT for breast cancer. The results show that the RapidArc technique in Eclipse version 11 does not improve all aspects of the treatment plans for the breast cases automatically and easily, but it needs to be manipulated by extra techniques to create acceptable plans thus further research is needed.
Show less
Date Issued: 2015
PURL: http://purl.flvc.org/fau/fd/FA00004526, http://purl.flvc.org/fau/fd/FA00004526
Subject Headings: Breast -- Cancer -- Treatment, Cancer -- Radiation therapy, Image guided radiation therapy, Radiation dosimetry, Radiotherapy -- Technological innovations
Format: Document (PDF)

Title: Dose Validation for Partial Accelerated Breast Irradiation treated with the SAVI Applicator.
Creator: Pinder, Janeil K., Pella, Silvia, Leventouri, Theodora, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: The purpose of this study is to verify and validate the dose at various points of interest in accelerated partial breast irradiation (APBI) treated with the Strut Adjusted Volume Implant (SAVI) applicator using Thermoluminescent Dosimeters (TLDs). A set of CT images were selected from a patient’s data who had received APBI using the SAVI applicator. The images were used to make 3D models. TLDs were calibrated for Brachytherapy. Various points of interest were marked out and slots were carved...
Show moreThe purpose of this study is to verify and validate the dose at various points of interest in accelerated partial breast irradiation (APBI) treated with the Strut Adjusted Volume Implant (SAVI) applicator using Thermoluminescent Dosimeters (TLDs). A set of CT images were selected from a patient’s data who had received APBI using the SAVI applicator. The images were used to make 3D models. TLDs were calibrated for Brachytherapy. Various points of interest were marked out and slots were carved in the 3D models to fit the TLDs. CT scans were taken of the 3D models with expanded SAVI applicator inserted. A plan was made following B-39 protocol. The TLDs were read and the absorbed doses were calculated and compared to the delivered doses. The results of this study show that the overall average reading of the TLDs is within expected value. The TPS shows overestimated dose calculations for brachytherapy.
Show less
Date Issued: 2017
PURL: http://purl.flvc.org/fau/fd/FA00005942
Subject Headings: Dissertations, Academic -- Florida Atlantic University, Thermoluminescence dosimetry., Brachytherapy., Radiotherapy Dosage., Breast--Cancer--Radiotherapy.
Format: Document (PDF)

Title: Dosimetric and Radiobiological Plan Evaluation Parameters for Fractionated High-Dose Rate GYN Brachytherapy.
Creator: Shojaei, Marjan, Pella, Silvia, Leventouri, Theodora, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Intracavitary high-dose-rate brachytherapy (HDRBT) is a treatment option for endometrial cancer, depending on the cancer stage. Because of the steep high dose gradient of HDRBT, very small differences in the treatment plans, surrounding organ’s anatomy, or procedures during the treatment could potentially cause significant dose variation to the tumor, as well as organs at risks (OAR) nearby the treatment area, which could result in unwanted radiobiological side effects. In this retrospective...
Show moreIntracavitary high-dose-rate brachytherapy (HDRBT) is a treatment option for endometrial cancer, depending on the cancer stage. Because of the steep high dose gradient of HDRBT, very small differences in the treatment plans, surrounding organ’s anatomy, or procedures during the treatment could potentially cause significant dose variation to the tumor, as well as organs at risks (OAR) nearby the treatment area, which could result in unwanted radiobiological side effects. In this retrospective study, the radiobiological plan evaluation parameters Equivalent Uniform Dose (EUD), Normal Tissue Complication Probability (NTCP) are used as assessment tools to evaluate HDRBT plans. Furthermore, gynecological applicator position in the coordinate system, and possible dose variations to the tumor and critical organs from the initial fraction in comparison with subsequent fractions over the entire multi fractionated treatment are studied. The evaluations were performed for 118 HDR treatment plans for 30 patients by registration of the subsequent treatment plans into the initial CT-image guided plan. Dose fractionation regimens varied from 4Gy to 7Gy per fraction, 1 or 2 fractions per week, depending on the cancer stage. Our results demonstrate no significant radiobiological impacts on organs at risks (OAR). In addition, the results of the applicator positions’ study indicate that improvement of immobilization and localization devices are recommended.
Show less
Date Issued: 2018
PURL: http://purl.flvc.org/fau/fd/FA00013144
Subject Headings: Brachytherapy, Radiobiology, Radiation dosimetry--Evaluation
Format: Document (PDF)

Title: Dosimetric and Radiobiological Comparison of the Effects of High Definition versus Normal Collimation on Treatment Plans for Stereotactic Lung Cancer Radiation Therapy.
Creator: Pudasaini, Mukunda Prasad, Pella, Silvia, Leventouri, Theodora, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Stereotactic Body Radiation Therapy (SBRT) is a modern precision radiation therapy to deliver the dose in 1 to 5 fractions with high target dose conformity, and steep dose gradient towards healthy tissues. The dose delivered is influenced by the leaf width of the MLC, especially in case of SBRT. Treatment plans with high definition (HD) MLC having leaf-width 2.5 mm and normal MLC having leaf-width 5 mm, were compared to quantify dosimetric and radiobiological parameters. Dosimetric parameters...
Show moreStereotactic Body Radiation Therapy (SBRT) is a modern precision radiation therapy to deliver the dose in 1 to 5 fractions with high target dose conformity, and steep dose gradient towards healthy tissues. The dose delivered is influenced by the leaf width of the MLC, especially in case of SBRT. Treatment plans with high definition (HD) MLC having leaf-width 2.5 mm and normal MLC having leaf-width 5 mm, were compared to quantify dosimetric and radiobiological parameters. Dosimetric parameters conformity indices (CI), gradient indices (GI) and heterogeneity indices (HI) were compared. The radiobiological parameters were evaluated by normal tissue complication probability (NTCP) and tumor control probability (TCP) based on the equivalent uniform dose (EUD). The results show that there is dosimetric and radiobiological merit of the HD MLC over the normal MLC. However, the improvement is not consistent with all the plans and thus further research is required prior to conclusion.
Show less
Date Issued: 2018
PURL: http://purl.flvc.org/fau/fd/FA00013148
Subject Headings: Radiosurgery, Lung Neoplasms, Radiation dosimetry, Radiobiology
Format: Document (PDF)

Title: An Algorithm to Determine IMRT Optimization Parameters within the Elekta Monaco® Treatment Planning System that Increases Dose Homogeneity and Dose Conformity in the Planning Target Volume.
Creator: Gregorisch, David, Pella, Silvia, Kyriacou, Andreas, Florida Atlantic University, Department of Physics, Charles E. Schmidt College of Science
Abstract/Description: An algorithm to determine IMRT optimization parameters within the Elekta Monaco® treatment planning system that increases dose homogeneity and dose conformity in the planning target volume was developed. This algorithm determines IMRT optimization parameters by calculating the difference between two pairs of dose points along the target volume’s dose volume histogram: Dmax – Dmin, and D2 – D98. The algorithm was tested on the Elekta Monaco® Treatment Planning System at GenesisCare of Coconut...
Show moreAn algorithm to determine IMRT optimization parameters within the Elekta Monaco® treatment planning system that increases dose homogeneity and dose conformity in the planning target volume was developed. This algorithm determines IMRT optimization parameters by calculating the difference between two pairs of dose points along the target volume’s dose volume histogram: Dmax – Dmin, and D2 – D98. The algorithm was tested on the Elekta Monaco® Treatment Planning System at GenesisCare of Coconut Creek, Florida using CT data from 10 anonymized patients with non-small cell lung cancer of various tumor sizes and locations. Nine iterations of parameters were tested on each patient. Once the ideal parameters were found, the results were evaluated using the ICRU report 83 homogeneity index as well as the Paddick conformity index. As an outcome of this research, it is recommended that at least three iterations of IMRT optimization parameters should be calculated to find the ideal parameters.
Show less
Date Issued: 2022
PURL: http://purl.flvc.org/fau/fd/FA00013990
Subject Headings: Radiotherapy, Algorithm, Medical physics
Format: Document (PDF)

FAU Theses and Dissertations (16)	+ -
FAU Graduate Student Research (5)	+ -

Medical physics (4)	+ -
Radiation dosimetry (4)	+ -
Radiation dosimetry--Evaluation (3)	+ -
Brachytherapy (2)	+ -
Radiobiology (2)	+ -

Algorithm (1)	+ -
Artificial intelligence -- Medical applications (1)	+ -
Biophysics (1)	+ -
Brachytherapy. (1)	+ -
Breast--Cancer--Radiotherapy. (1)	+ -
Breast--Cancer--Treatment (1)	+ -
Breast -- Cancer -- Treatment (1)	+ -
Cancer (1)	+ -
Cancer -- Intraoperative radiotherapy (1)	+ -
Cancer -- Radiotherapy (1)	+ -
Cancer--Treatment (1)	+ -
Cancer -- Radiation therapy (1)	+ -
Carcinoma, Hepatocellular (1)	+ -
Coherence (Nuclear physics) (1)	+ -
Dissertations, Academic -- Florida Atlantic University (1)	+ -
Electron beams -- Therapeutic use (1)	+ -
Electron density (1)	+ -
Generative organs, Female -- Cancer -- Treatment (1)	+ -
Image guided radiation therapy (1)	+ -
Image guided radiotherapy (1)	+ -
Image guided radiation therapy (1)	+ -
Imaging systems in medicine (1)	+ -
Immobilization (1)	+ -
Integrated circuits (1)	+ -
Leipzig (1)	+ -

Electronic Thesis or Dissertation (16)	+ -
abstract (3)	+ -
poster (2)	+ -

Pella, Silvia (21)	+ -
Charles E. Schmidt College of Science (16)	+ -
Department of Physics (16)	+ -
Florida Atlantic University (15)	+ -
Leventouri, Theodora (9)	+ -

Search In

Pages

Pages

Sort Results By:

Narrow results by:

Collection

Topical Subject

Genre

Type of Resource

Language

Creator

Format

Owner