Objective(s): Recent implementation of multileaf collimator (MLC) into CyberKnife (CK) robotic ra... more Objective(s): Recent implementation of multileaf collimator (MLC) into CyberKnife (CK) robotic radiosurgery system raises the necessity for CK patient specific quality assurance (QA) procedures. Gafchromic EBT3 film, cylindrical diode array and planar ion chamber were examined for their use of dose verification of CK plans. This study aims to investigate the feasibility of MapCheck planar dose array system as a patient specific QA device for CK plan. Methods: MapCheck (Sun Nuclear 1175) detector with 445 solid state detectors and specifications: center array spacing: 7.07 mm, active detector area: 0.8 mm x 0.8 mm, total buildup to detector junction: 2.0 ± 0.1 g/cm2 was used for the dose verification of CK plan. Four fiducial markers were placed according to Accuray recommendations on MapCheck device to enable image-based setup. A pre-treatment plan dose verification was created in Precision (V2.0.0.1) treatment planning system. The central axis of the device was aligned with plannin...
Objectives: The American Society for Radiation Oncology guidelines for management of brain metast... more Objectives: The American Society for Radiation Oncology guidelines for management of brain metastases (mets) suggests stereotactic radiosurgery (SRS) to be the primary treatment choice for multiple mets (multimets) when quality of life is considered as the most important outcome. Recently developed approach, HyperArc VMAT planning, fulfill the demands of treating multimets with SRS. Here, we present the competitive planning treatment approach of stereotactic treatment of multimets with Cyberknife (CK) MLC collimator using voxel-less optimization (VOLO). Methods: SRS planning was carried out for 10 brain multimet patients with the number of mets ranging from 4-15. The treatment planning process was carried out with a Precision 2.0 TPS and VOLO optimization algorithm. Ray tracing algorithm was utilized for all calculations due to homogeneous brain density. All plans were setup with head_MLC treatment anatomy, full path set and 6D tracking method. The beam direction was set to never in...
Objectives: The implementation of multileaf collimator (MLC) into CyberKnife (CK) robotic radiosu... more Objectives: The implementation of multileaf collimator (MLC) into CyberKnife (CK) robotic radiosurgery system raises the necessity for CK patient specific quality assurance (QA) procedures. Different dosimeters, such as gafchromic EBT3 film, cylindrical diode array and planar ion chamber, were examined for their use of dose verification of CK plans. The feasibility of using MapCheck planar dose array system for a patient specific QA device for intensitymodulated radiation therapy (IMRT) CK plan was presented in this study. Methods: Dose verification of 28 CK IMRT plans using MLC (10 intracranial and 28 extracranial lesions) were performed with MapCheck (Sun Nuclear 1175) detector (specifications: 445 solid state detectors, center array spacing: 7.07 mm, active detector area: 0.8 mm x 0.8 mm, total buildup to detector junction: 2.0 ± 0.1 g/cm2). Treatment volumes ranged from 3 cc to 334 cc (median 27.05 cc). 10 intracranial plans included 3 single lesion and 7 multiple lesions (2-15 ...
ii Nanotechnology has been undergoing tremendous development in recent decades, driven by realize... more ii Nanotechnology has been undergoing tremendous development in recent decades, driven by realized perceived applications of nanomaterials in electronics, therapeutics, imaging, sensing, environmental remediation, and consumer products. Along with these developments there have been increased evidences that engineered nanomaterials are often associated with hazardous effects they invoke in biological and ecosystems through intentional designs or unintentional discharge. Consequently there is a crucial need for documenting and understanding the interactions between nanoparticles and biological and ecosystems. This dissertation is aimed at bridging such a knowledge gap by examining the biological and ecological responses to carbon nanoparticles, a major class of nanomaterials which have been mass produced and extensively studied for their rich physical properties and commercial values. Chapter I of this dissertation offers a comprehensive review on the structures, properties, applicati...
Seed coat permeability was examined using a model that tested the effects of soaking tomato (Sola... more Seed coat permeability was examined using a model that tested the effects of soaking tomato (Solanum lycopersicon) seeds in combination with carbon-based nanomaterials (CBNMs) and ultrasonic irradiation (US). Penetration of seed coats to the embryo by CBNMs, as well as CBNMs effects on seed germination and seedling growth, was examined. Two CBNMs, C60(OH)20 (fullerol) and multiwalled nanotubes (MWNTs), were applied at 50 mg/L, and treatment exposure ranged from 0 to 60 minutes. Bright field, fluorescence, and electron microscopy and micro-Raman spectroscopy provided corroborating evidence that neither CBNM was able to penetrate the seed coat. The restriction of nanomaterial (NM) uptake was attributed to the semipermeable layer located at the innermost layer of the seed coat adjacent to the endosperm. Seed treatments using US at 30 or 60 minutes in the presence of MWNTs physically disrupted the seed coat; however, the integrity of the semipermeable layer was not impaired. The germina...
Objective(s): Recent implementation of multileaf collimator (MLC) into CyberKnife (CK) robotic ra... more Objective(s): Recent implementation of multileaf collimator (MLC) into CyberKnife (CK) robotic radiosurgery system raises the necessity for CK patient specific quality assurance (QA) procedures. Gafchromic EBT3 film, cylindrical diode array and planar ion chamber were examined for their use of dose verification of CK plans. This study aims to investigate the feasibility of MapCheck planar dose array system as a patient specific QA device for CK plan. Methods: MapCheck (Sun Nuclear 1175) detector with 445 solid state detectors and specifications: center array spacing: 7.07 mm, active detector area: 0.8 mm x 0.8 mm, total buildup to detector junction: 2.0 ± 0.1 g/cm2 was used for the dose verification of CK plan. Four fiducial markers were placed according to Accuray recommendations on MapCheck device to enable image-based setup. A pre-treatment plan dose verification was created in Precision (V2.0.0.1) treatment planning system. The central axis of the device was aligned with plannin...
Objectives: The American Society for Radiation Oncology guidelines for management of brain metast... more Objectives: The American Society for Radiation Oncology guidelines for management of brain metastases (mets) suggests stereotactic radiosurgery (SRS) to be the primary treatment choice for multiple mets (multimets) when quality of life is considered as the most important outcome. Recently developed approach, HyperArc VMAT planning, fulfill the demands of treating multimets with SRS. Here, we present the competitive planning treatment approach of stereotactic treatment of multimets with Cyberknife (CK) MLC collimator using voxel-less optimization (VOLO). Methods: SRS planning was carried out for 10 brain multimet patients with the number of mets ranging from 4-15. The treatment planning process was carried out with a Precision 2.0 TPS and VOLO optimization algorithm. Ray tracing algorithm was utilized for all calculations due to homogeneous brain density. All plans were setup with head_MLC treatment anatomy, full path set and 6D tracking method. The beam direction was set to never in...
Objectives: The implementation of multileaf collimator (MLC) into CyberKnife (CK) robotic radiosu... more Objectives: The implementation of multileaf collimator (MLC) into CyberKnife (CK) robotic radiosurgery system raises the necessity for CK patient specific quality assurance (QA) procedures. Different dosimeters, such as gafchromic EBT3 film, cylindrical diode array and planar ion chamber, were examined for their use of dose verification of CK plans. The feasibility of using MapCheck planar dose array system for a patient specific QA device for intensitymodulated radiation therapy (IMRT) CK plan was presented in this study. Methods: Dose verification of 28 CK IMRT plans using MLC (10 intracranial and 28 extracranial lesions) were performed with MapCheck (Sun Nuclear 1175) detector (specifications: 445 solid state detectors, center array spacing: 7.07 mm, active detector area: 0.8 mm x 0.8 mm, total buildup to detector junction: 2.0 ± 0.1 g/cm2). Treatment volumes ranged from 3 cc to 334 cc (median 27.05 cc). 10 intracranial plans included 3 single lesion and 7 multiple lesions (2-15 ...
ii Nanotechnology has been undergoing tremendous development in recent decades, driven by realize... more ii Nanotechnology has been undergoing tremendous development in recent decades, driven by realized perceived applications of nanomaterials in electronics, therapeutics, imaging, sensing, environmental remediation, and consumer products. Along with these developments there have been increased evidences that engineered nanomaterials are often associated with hazardous effects they invoke in biological and ecosystems through intentional designs or unintentional discharge. Consequently there is a crucial need for documenting and understanding the interactions between nanoparticles and biological and ecosystems. This dissertation is aimed at bridging such a knowledge gap by examining the biological and ecological responses to carbon nanoparticles, a major class of nanomaterials which have been mass produced and extensively studied for their rich physical properties and commercial values. Chapter I of this dissertation offers a comprehensive review on the structures, properties, applicati...
Seed coat permeability was examined using a model that tested the effects of soaking tomato (Sola... more Seed coat permeability was examined using a model that tested the effects of soaking tomato (Solanum lycopersicon) seeds in combination with carbon-based nanomaterials (CBNMs) and ultrasonic irradiation (US). Penetration of seed coats to the embryo by CBNMs, as well as CBNMs effects on seed germination and seedling growth, was examined. Two CBNMs, C60(OH)20 (fullerol) and multiwalled nanotubes (MWNTs), were applied at 50 mg/L, and treatment exposure ranged from 0 to 60 minutes. Bright field, fluorescence, and electron microscopy and micro-Raman spectroscopy provided corroborating evidence that neither CBNM was able to penetrate the seed coat. The restriction of nanomaterial (NM) uptake was attributed to the semipermeable layer located at the innermost layer of the seed coat adjacent to the endosperm. Seed treatments using US at 30 or 60 minutes in the presence of MWNTs physically disrupted the seed coat; however, the integrity of the semipermeable layer was not impaired. The germina...
Uploads