An investigation of kV CBCT image quality and dose reduction for volume-of-interest imaging using dynamic collimation

Medical Physics
David Parsons, James L Robar

Abstract

The focus of this work was to investigate the improvements in image quality and dose reduction for volume-of-interest (VOI) kilovoltage-cone beam CT (CBCT) using dynamic collimation. A prototype iris aperture was used to track a VOI during a CBCT acquisition. The current aperture design is capable of 1D translation as a function of gantry angle and dynamic adjustment of the iris radius. The aperture occupies the location of the bow-tie filter on a Varian On-Board Imager system. CBCT and planar image quality were investigated as a function of aperture radius, while maintaining the same dose to the VOI, for a 20 cm diameter cylindrical water phantom with a 9 mm diameter bone insert centered on isocenter. Corresponding scatter-to-primary ratios (SPR) were determined at the detector plane with Monte Carlo simulation using EGSnrc. Dose distributions for various sizes VOI were modeled using a dynamic BEAMnrc library and DOSXYZnrc. The resulting VOI dose distributions were compared to full-field distributions. SPR was reduced by a factor of 8.4 when decreasing iris diameter from 21.2 to 2.4 cm (at isocenter). Depending upon VOI location and size, dose was reduced to 16%-90% of the full-field value along the central axis plane and down...Continue Reading

References

May 1, 1995·Medical Physics·D W RogersT R Mackie
Jun 1, 1995·Physics in Medicine and Biology·D J KadrmasC B Lim
Jul 7, 2001·Medical Physics·C M MaUNKNOWN American Association of Physicists in Medicine
Jul 20, 2002·International Journal of Radiation Oncology, Biology, Physics·David A JaffrayAlvaro A Martinez
Jul 11, 2006·IEEE Transactions on Medical Imaging·Lifeng YuXiaochuan Pan
Mar 1, 2007·Physics in Medicine and Biology·George X DingCharles W Coffey
Jan 24, 2008·AJR. American Journal of Roentgenology·Marilyn J GoskeNora Tuggle
Nov 19, 2010·Radiology·James A Brink, E Stephen Amis
Jul 27, 2012·Medical Physics·James L RobarAlex Macdonald
Jan 7, 2014·Medical Physics·Del Leary, James L Robar

❮ Previous
Next ❯

Citations

Jun 4, 2016·Journal of X-ray Science and Technology·Erik PearsonCharles Pelizzari
Mar 8, 2017·AJR. American Journal of Roentgenology·Timothy P SzczykutowiczPerry J Pickhardt
Sep 14, 2017·Medical Physics·Aymeric ReshefIsabelle Bloch
May 23, 2018·Journal of Applied Clinical Medical Physics·Thomas C LarsenHan Wen
Sep 19, 2019·Journal of Medical Imaging·Wenying WangJ Webster Stayman
Jun 12, 2021·Advances in Radiation Oncology·Kimmie de BruinWilko F A R Verbakel

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.