BACKGROUND This paper compares the calculated dose to target and normal tissues when using pencil beam (PBC), superposition/convolution (AAA) and Monte Carlo (MC) algorithms for whole breast (WBI) and accelerated partial breast irradiation (APBI) treatment plans. METHODS Plans for 10 patients who met all dosimetry constraints on a prospective APBI protocol when using PBC calculations were rec...

To compare the radiation dose to normal cardiac tissue for 3Dimensional (3D) conformal external beam partial breast irradiation (PBI) and standard whole breast irradiation (WBI), and examine the effect of tumor bed location. For 14 patients with left breast tumors randomized on the National Surgical Adjuvant Breast and Bowel Project B-39 protocol, computer-generated radiotherapy treatment plans...

primary and widely in use computed tomography (ct) dose descriptor is a volumetric ct dose index (ctdiv) that is usually measured by a pencil ionization chamber with active length of 100mm and polymethyl methacrylate (pmma) phantom. ctdiv depends on scan parameters such as mas, kv, collimation, tube rotation time but is independent of patient’s size and shape. for the purpose of a good estimati...

Improving Dose Coverage In Tumors Of The Head And Neck By Reducing Lateral Electronic Disequilibrium. Shada J. Wadi-Ramahi Rush University Medical Center, Chicago, IL Abstract:This research investigates the use of a low-strength (< 1.0 T) longitudinal magnetic field with external photon beams in improving the dose coverage of the regions around air cavities. This is a problem relevant for tumor...

Introduction: Nowadays radiosensitive polymer gels are used as a reliable dosimetry tool for verification of 3D dose distributions. Special characteristics of these dosimeters have made them useful for verification of complex dose distributions in clinical situations. The aim of this work was to evaluate the capability of a normoxic polymer gel to determine electron dose distributions in differ...

BACKGROUND Cranial reirradiation is clinically appropriate in some cases but cumulative radiation dose to critical normal structures remains a practical concern. The authors developed a simple technique in 3D conformal proton craniospinal irradiation (CSI) to block organs at risk (OAR) while minimizing underdosing of adjacent target brain tissue. METHODS Two clinical cases illustrate the use ...

Measurements were performed to assess the dose equivalent outside a primary proton treatment field, using a silicon-on-insulator (SOI) microdosimeter. The SOI microdosimeter was placed on the surface of an anthropomorphic phantom and dose equivalents were determined as a function of lateral distance from a typical passively scattered and modulated prostate treatment field. Measurements were als...

Exposure index (EI) is an indicator of dose used to determine overexposed, optimal and underexposed images so that this study discusses the effect EI variations on subjective image quality assessment lumbosacral examination. This research uses descriptive quantitative method by filling out questionnaires calculating radiation output dose. Then draw conclusions, perform a visual grading analysis...

conclusion scout views may be useful in determining dose and image quality in ct scanning; however, it is necessary to first determine the most appropriate scout view for ct scans. background while using the automatic exposure control technique in computed tomography (ct), the scout view determines the radiation dose for the ct scan by taking anatomical morphology into consideration. objectives...

Introduction: Digital radiography possesses a wide dynamic range and has a major advantage in producing an acceptable image of diagnostic value even though overexposure occurs. Lumbar spine (LS) radiography is the most common examinations that gives high radiation dose to patients and accounts for the highest collective population dose of any conventional radiographic ...