Assessing Radiology and Radiation Therapy Needs for Cancer Care in Low-and-Middle-Income Countries: Insight From a Global Survey of Departmental and Institutional Leaders.

Purpose: The global cancer burden and mortality rates are increasing, with significant disparities in access to care in low- and middle-income countries (LMICs). This study aimed to identify radiology and radiation therapy needs in LMICs from the perspective of departmental and institutional leaders.

Methods And Materials: A survey was developed and conducted by the American Association of Physicists in Medicine Global Needs Assessment Committee and the American Association of Physicists in Medicine International Council.

Patient specific quality assurance of volumetric modulated arc therapy of synchronous bilateral breast cancer.

Synchronous bilateral breast cancers (SBBC) present a considerable issue in external beam radiotherapy because of large fields size and large target volumes. Mono-isocentric volumetric modulated arc therapy (VMAT) appears as an appropriate irradiation technique for these types of tumors. The aim of this study was to demonstrate the utility of a 3D DVH pretreatment quality assurance program in VMAT of SBBC cases.

VMAT partial arc technique decreases dose to organs at risk in whole pelvic radiotherapy for prostate cancer when compared to full arc VMAT and IMRT.

Whole pelvic radiotherapy (WPRT) can sterilize microscopic lymph node metastases in treatment of prostate cancer. WPRT, compared to prostate only radiotherapy (PORT), is associated with increased acute gastrointestinal, and hematological toxicities. To further explore minimizing normal tissue toxicities associated with WPRT in definitive IMRT for prostate cancer, this planning study compared dosimetric differences between static 9-field-IMRT, full arc VMAT, and mixed partial-full arc VMAT techniques.

Robustness of single-isocenter multiple-metastasis stereotactic radiosurgery end-to-end testing across institutions.

The accuracy of stereotactic radiosurgery (SRS) to multiple metastases with a single-isocenter using high definition dynamic radiosurgery (HDRS) was evaluated across institutions. An SRS plan was delivered at six HDRS-capable institutions to an anthropomorphic phantom consisting of point, film, and 3D-gel dosimeters. Direct dose comparison and gamma analysis were used to evaluate the accuracy.

The Impact of Dose Rate on the Accuracy of Step-and-Shoot Intensity-modulated Radiation Therapy Quality Assurance Using Varian 2300CD.

Introduction: Intensity-modulated radiation therapy (IMRT) delivery using "step-and-shoot" technique on Varian C-Series linear accelerator (linac) is influenced by the communication frequency between the multileaf collimator and linac controllers. Hence, the dose delivery accuracy is affected by the dose rate.

Aim: Our aim was to quantify the impact of using two dose rates on plan quality assurance (QA).

Enhanced dynamic wedge output factors for Varian 2300CD and the case for a reference database.

Dose inhomogeneity in treatment planning can be compensated using physical wedges. Enhanced dynamic wedges (EDW) were introduced by Varian to overcome some of the shortcomings of physical wedges. The objectives of this study were to measure EDW output factors for 6 MV and 20 MV photon energies for a Varian 2300CD.

A validation of carbon fiber imaging couch top modeling in two radiation therapy treatment planning systems: Philips Pinnacle3 and BrainLAB iPlan RT Dose.

Background: Carbon fiber (CF) is now the material of choice for radiation therapy couch tops. Initial designs included side metal bars for rigidity; however, with the advent of IGRT, involving on board imaging, new thicker CF couch tops without metal bars have been developed. The new design allows for excellent imaging at the expense of potentially unacceptable dose attenuation and perturbation.

A simple quality assurance test tool for the visual verification of light and radiation field congruent using electronic portal images device and computed radiography.

Background: The radiation field on most megavoltage radiation therapy units are shown by a light field projected through the collimator by a light source mounted inside the collimator. The light field is traditionally used for patient alignment. Hence it is imperative that the light field is congruent with the radiation field.

Accelerated partial breast irradiation using external beam conformal radiation therapy: a review.

Lumpectomy followed by whole breast radiation therapy (i.e. breast conservation therapy (BCT)) is the standard of care for management of early stage breast cancer.

Accelerated Partial Breast Irradiation (APBI): A review of available techniques.

Breast conservation therapy (BCT) is the procedure of choice for the management of the early stage breast cancer. However, its utilization has not been maximized because of logistics issues associated with the protracted treatment involved with the radiation treatment. Accelerated Partial Breast Irradiation (APBI) is an approach that treats only the lumpectomy bed plus a 1-2 cm margin, rather than the whole breast.

Determination of the photon beam attenuation by the Brainlab imaging couch: angular and field size dependence.

Highly attenuating radiation treatment couches are no longer useful in the present era of radiotherapy utilizing IMRT and IGRT. Carbon fibers couch tops with its high tensile strength and low density present a useful alternative. The objective of the current study was to quantify the attenuation of megavoltage photons through a Brainlab imaging couch top and headrest at various angles and field sizes.

What are the standards by which bone mass measurement at peripheral skeletal sites should be used in the diagnosis of osteoporosis?

Measurement of bone mineral density (BMD) at central skeletal sites with dual X-ray absorptiometry is the "gold standard" both for the diagnosis of osteoporosis using the criteria of the World Health Organization (WHO) and for monitoring individuals receiving antiresorptive treatment for osteoporosis. Measurement of BMD at peripheral sites (peripheral BMD) can be used to assess fracture risk, but application of the WHO criteria gives different prevalence values for "osteoporosis" with peripheral devices, and different risks for fracture at the same cut points. The International Society for Clinical Densitometry Position Development Conference panelists reached the following conclusions about peripheral BMD testing: First, WHO T-score criteria should not be used with peripheral devices.