The physical basis for the measurement of Hp(10) and H*(10) in mixed high-energy electron and photon fields was developed for the general case of non-existing secondary charged particle equilibrium at the reference depth of 10 mm. Several mixed fields, with different electron fluence distributions were produced and the corresponding depth ionisation curves were measured in a Makrolon phantom. B...

INTRODUCTION Wide agreement has been reached among the main Bodies and Organizations involved in standardization of radiation protection to define as operational quantity for individual monitoring of external exposure, the personal dose equivalent, Hp(d) (1,2,3). However, as Hp(d) is defined in the human body, it is not a measurable quantity. In practice, it has to be estimated from the indicat...

BACKGROUND CT based brachytherapy allows 3-dimensional (3D) assessment of organs at risk (OAR) doses with dose volume histograms (DVHs). The purpose of this study was to compare computed tomography (CT) based volumetric calculations and International Commission on Radiation Units and Measurements (ICRU) reference-point estimates of radiation doses to the bladder and rectum in patients with carc...

introduction: this study investigates to what extent the computed dose received by lung tissue in a commercially available treatment planning system (tps) for 192ir high-dose-rate breast brachytherapy is accurate in view of tissue inhomogeneities and presence of ribs. materials and methods: a ct scan of the breast was used to construct a patient-equivalent phantom in the clinical treatment plan...

Reliable attenuation correction represents an essential component of the long chain of modules required for the reconstruction of artifact-free, quantitative brain positron emission tomography (PET) images. In this work we demonstrate the proof of principle of segmented magnetic resonance imaging (MRI)-guided attenuation and scatter corrections in three-dimensional (3D) brain PET. We have devel...

Introduction: This study investigates to what extent the computed dose received by lung tissue in a commercially available treatment planning system (TPS) for 192Ir high-dose-rate breast brachytherapy is accurate in view of tissue inhomogeneities and presence of ribs. Materials and Methods: A CT scan of the breast was used to construct a patient-equivalent phantom in the clinical treatment plan...

Microwave-induced thermoacoustic imaging (MTAI) is a potential nonionizing candidate for breast tumor detection due to its high contrast of tissue dielectric absorption and resolution ultrasonography. However, conventional MTAI systems need contact the targets through ultrasound-coupling medium efficient transmission signals. This major drawback applications such as navigation open surgeries, b...

Background: In treating patients with radiation, the degree of accuracy for the delivery of tumor dose is recommended to be within ± 5% by ICRU in report 24. The experimental studies have shown that the presence of low-density inhomogeneity in areas such as the lung can lead to a greater than 30% change in the water dose data. Therefore, inhomogeneity corrections should be used in treatment pla...

In this work, conversion coefficients for the operational quantity H'(3;Ω) have been calculated for both mono-energetic photons from 2 keV to 50 MeV for angles of incidence from 0° up to 180° in steps of 15° (to complement ICRU 57) as well as for photon reference radiation qualities (to complement ISO 4037). Finally, parameters necessary to determine the influence of the air density on the conv...

Background: Purpose of the study is to evaluate field-in-field (FIF) and sliding-window intensity modulated radiation therapy (SW-IMRT) treatment plans in terms of homogeneity index (HI), conformity index (CI) and normal tissue doses for organs at risk (OAR) in patients with endometrial carcinoma along with deriving a new expression for CI. Materials and Methods: Four different FIF plans with d...