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Accurate verification of balloon rotation correction for the contura® multi-lumen device for accelerated partial breast irradiation
Title
Accurate verification of balloon rotation correction for the contura® multi-lumen device for accelerated partial breast irradiation.
Creator
Kyriacou, Andreas, Benda, R., Vargas, C., Lyden, M., Vicini , F., Leventouri, Theodora, Graduate College, Kasper, M.
Date Issued
2011-04-08
PURL
http://purl.flvc.org/fcla/dt/3171046
Subject Headings
Breast --Cancer --Radiotherapy, Brachytherapy, Breast Neoplasms --surgery
Format
Document (PDF)
Comparison study between BrainLab and Eclipse for small cancer lesions
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.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00005812
Format
Document (PDF)
Crystal structure studies of cone snail shells by powder x-ray diffraction
Title
Crystal structure studies of cone snail shells by powder x-ray diffraction.
Creator
Khanal, Suraj P., Kathriarachchi, Vindu, Kyriacou, Andreas, Leventouri, Theodora, Graduate College
Date Issued
2011-04-08
PURL
http://purl.flvc.org/fcla/dt/3165805
Subject Headings
Snails, Shells, X-rays --Diffraction
Format
Document (PDF)
Effect of preparation temperature on crystal structure and magnetic properties of nanophase Fe-substituted hydroxyapatite
Title
Effect of preparation temperature on crystal structure and magnetic properties of nanophase Fe-substituted hydroxyapatite.
Creator
Kathriarachchi, Vindu, Leventouri, Theodora, Sorge, Korey D., Graduate College
Date Issued
2013-04-12
PURL
http://purl.flvc.org/fcla/dt/3361934
Subject Headings
Hydroxyapatite, Magnetic properties, Crystals--Structure, Temperature
Format
Document (PDF)
Effect of Preparation Temperature on Crystal Structure and Magnetic Properties of Nanophase Fe-Substituted Hydroxyapatite
Title
Effect of Preparation Temperature on Crystal Structure and Magnetic Properties of Nanophase Fe-Substituted Hydroxyapatite.
Creator
Kathriarachchi, Vindu, Sorge, Korey D., Leventouri, Theodora, Graduate College
Abstract/Description
The purpose of the study is to investigate the effect of preparation temperature on the crystal structure and magnetic properties of nanophase Fe-substituted Hydroxyapatite. Multisubstituted Hydroxyapatite (HAp), Ca5(PO4)3OH, is the main mineral phase in physiological apatite, ~70 wt% in bones and dentin, and ~96 wt% in enamel. Iron is one of the minor substitution elements (0.01-0.1 wt% in bone and 0.003 wt% in enamel) replacing Ca in the HAp structure. Research interest on Fe-HAp is related...
Show moreThe purpose of the study is to investigate the effect of preparation temperature on the crystal structure and magnetic properties of nanophase Fe-substituted Hydroxyapatite. Multisubstituted Hydroxyapatite (HAp), Ca5(PO4)3OH, is the main mineral phase in physiological apatite, ~70 wt% in bones and dentin, and ~96 wt% in enamel. Iron is one of the minor substitution elements (0.01-0.1 wt% in bone and 0.003 wt% in enamel) replacing Ca in the HAp structure. Research interest on Fe-HAp is related to the fact that Fe for Ca substitution reduces the solubility of HAp therefore it functions as a cavities preventive agent. In contrast, Fe overload causes a decrease in bone mechanical strength. Furthermore, Fe-HAp can find applications in hyperthermia based anti-cancer treatments and in magnetic resonance imaging (MRI) contrast agents. Two sets of Ca5-xFex(PO4)3OH samples (x=0,0.05,0.1,0.2,0.3) were synthesized by a chemical precipitation method at physiological temperature (370C) and 800C. The samples were calcinated at 6500C and deuterated at 6000C. The samples were characterized by x-ray powder diffraction (XRD), neutron powder diffraction (NPD) and SQUID Magnetometry. A single-phase system was detected for nominal iron content x≤0.1 by XRD phase identification in both sets of samples, while hematite (α-Fe2O3) and/or maghemite (γ- Fe2O3) develops starting at x=0.1. According to the magnetic measurements, sample with x=0 showed diamagnetic behavior while samples with Fe showed paramagnetic behavior. Combined Rietveld refinements of XRD and NPD patterns will provide accurate information on the effect of processing temperature on the crystallographic parameters of the nano-materials.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00005825
Format
Document (PDF)
Effect of preparation temperature on crystal structure properties on nanophase Fe-substituted hydroxyapatite
Title
Effect of preparation temperature on crystal structure properties on nanophase Fe-substituted hydroxyapatite.
Creator
Kathriarachchi, Vindu, Kyriacou, Andreas, Khanal, Suraj P., Leventouri, Theodora, Graduate College
Date Issued
2012-03-30
PURL
http://purl.flvc.org/fcla/dt/3342385
Format
Document (PDF)
Evaluation of surface dose outside the treatment area for breast cancer irradiation modalities using thermoluminescence dosimeters (TLDs)
Title
Evaluation of surface dose outside the treatment area for breast cancer irradiation modalities using thermoluminescence dosimeters (TLDs).
Creator
Khanal, Suraj P., Ouhib, Zoubir, Leventouri, Theodora, Graduate College
Date Issued
2013-04-12
PURL
http://purl.flvc.org/fcla/dt/3361319
Subject Headings
Thermoluminescence dosimetry, Breast--Cancer--Treatment
Format
Document (PDF)
Exploring Appropriate Offset Values for Pencil Beam and Monte Carlo Dose Optimization in Lung Stereotactic Body Radiotherapy Encompassing the Effects of Respiration and Tumor Location
Title
Exploring Appropriate Offset Values for Pencil Beam and Monte Carlo Dose Optimization in Lung Stereotactic Body Radiotherapy Encompassing the Effects of Respiration and Tumor Location.
Creator
Evans, Grant, Shang, Charles, Leventouri, Theodora, Graduate College
Abstract/Description
Purpose: To explore offset values in dose optimization with pencil beam (PB) algorithm to minimize dosimetric differences with plans calculated with Monte Carlo (MC) for lung cancer treatment with Stereotactic Body Radiotherapy (SBRT). Methods: 20 cases of Non-Small Cell Lung Cancer, treated with gated full motion range SBRT were selected. According to the proximity of the Gross Tumor Volume (GTV) to the chest wall, two groups are defined. Treatment plans were created on 4D average intensity...
Show morePurpose: To explore offset values in dose optimization with pencil beam (PB) algorithm to minimize dosimetric differences with plans calculated with Monte Carlo (MC) for lung cancer treatment with Stereotactic Body Radiotherapy (SBRT). Methods: 20 cases of Non-Small Cell Lung Cancer, treated with gated full motion range SBRT were selected. According to the proximity of the Gross Tumor Volume (GTV) to the chest wall, two groups are defined. Treatment plans were created on 4D average intensity projection (AIP) CT set with Brainlab iPlanDose® 4.1.2 planning system. The D97 of PTV was normalized to 50Gy using the fast PB and compared with MC. The optimized plan was then recomputed over each 4D respiratory phase, and compared with MC. Results: The mean difference in the PB and MC D97 of the ITV was 10.5% (±0.8%) of the prescription dose (50Gy). PB algorithm showed 2.3-2.4% less overestimation to the D97 of the ITV, when comparing to MC, in the maximum exhalation phase than in the maximal inhalation phase. Significantly smaller dose difference between PB and MC is also shown in plans for peripheral lesions (7.7 ± 0.7%) versus for central lesions (12.7±0.8%) (p< 0.01). Conclusions: The dosimetric differences between PB and MC can be reasonably predicted depending on the location of lesion in the lung, and may be used as offset value in dose optimization with PB. Caution is suggested when using the maximum inhalation phase for treatment planning.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00005813
Format
Document (PDF)
Motion challenges in high dose rate (HDR) brachytherapy
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)
Optimization algorithms for intensity modulated radiation treatment
Title
Optimization algorithms for intensity modulated radiation treatment.
Creator
Doozan, Brian, Leventouri, Theodora, Graduate College
Date Issued
2013-04-12
PURL
http://purl.flvc.org/fcla/dt/3361926
Subject Headings
Radiotherapy, Radiation dosimetry, Algorithms
Format
Document (PDF)
Preparation and characterization of fSWCNT/HAp-nylon hybridized composite biomaterial and mechanical testing
Title
Preparation and characterization of fSWCNT/HAp-nylon hybridized composite biomaterial and mechanical testing.
Creator
Khanal, Suraj P., Leventouri, Theodora, Graduate College
Abstract/Description
Synthetic hydroxyapatite HAp bears poor mechanical properties that limit its applicability in orthopedics. We study the possibility of overcoming such limitations by incorporating functionalized single walled carbon nanotube fSWCNT and polymerized є- caprolactam. Sonication method was used to disperse fSWCNT in the HAp. A simple hot blending method was used to incorporate HAp/fSWCNT powder with melted polymerized є-caprolactam. The fracture toughness of the composite material was tested in...
Show moreSynthetic hydroxyapatite HAp bears poor mechanical properties that limit its applicability in orthopedics. We study the possibility of overcoming such limitations by incorporating functionalized single walled carbon nanotube fSWCNT and polymerized є- caprolactam. Sonication method was used to disperse fSWCNT in the HAp. A simple hot blending method was used to incorporate HAp/fSWCNT powder with melted polymerized є-caprolactam. The fracture toughness of the composite material was tested in compliance with ASTM D-5045 standard. A critical stress intensity factor K1C of the composite material was found to be 3.55 MPa.m1/2, which is a value comparable to the one for cortical bone.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00005828
Format
Document (PDF)