Purpose: The purpose of this study is to determine the effect on the measured optical density of scanning on either side of a Gafchromic EBT and EBT2 film using an Epson (Epson Canada Ltd., Toronto, Ontario) 10000XL flat bed scanner.

Methods: Calibration curves were constructed using EBT2 film scanned in landscape orientation in both reflection and transmission mode on an Epson 10000XL scanner. Calibration curves were also constructed using EBT film. Potential errors due to an optical density difference from scanning the film on either side ("face up" or "face down") were simulated.

Results: Scanning the film face up or face down on the scanner bed while keeping the film angular orientation constant affects the measured optical density when scanning in reflection mode. In contrast, no statistically significant effect was seen when scanning in transmission mode. This effect can significantly affect relative and absolute dose measurements. As an application example, the authors demonstrate potential errors of 17.8% by inverting the film scanning side on the gamma index for 3%-3 mm criteria on a head and neck intensity modulated radiotherapy plan, and errors in absolute dose measurements ranging from 10% to 35% between 2 and 5 Gy.

Conclusions: Process consistency is the key to obtaining accurate and precise results in Gafchromic film dosimetry. When scanning in reflection mode, care must be taken to place the film consistently on the same side on the scanner bed.

Download full-text PDF

Source
http://dx.doi.org/10.1118/1.3355895DOI Listing

Publication Analysis

Top Keywords

optical density
16
potential errors
12
scanning side
12
film
10
errors optical
8
scanning
8
ebt ebt2
8
gafchromic film
8
film dosimetry
8
measured optical
8

Similar Publications

Background: This study aimed to evaluate the efficacy of polydopamine (PDA) functionalization on orthodontic brackets in inhibiting biofilm formation and promoting surface bioactivity to buffer the acidity of caries-causing bacteria around orthodontic brackets and prevent demineralization. The stability of the coating in artificial saliva (AS) and distilled water was evaluated, along with its effect on pH changes in simulated body fluid (SBF) and distilled water.

Methods: Maxillary incisor orthodontic brackets underwent PDA functionalization using a dopamine hydrochloride solution following a specific protocol.

View Article and Find Full Text PDF

Interface Modification by GaO Atomic Layers within Er-Doped GeO Nanofilms for Enhanced Electroluminescence and Operation Stability.

ACS Appl Mater Interfaces

January 2025

School of Materials Science and Engineering, Tianjin Key Lab for Rare Earth Materials and Applications, Nankai University, Tianjin 300350, China.

For silicon-based devices using dielectric oxides doped with rare earth ions, their electroluminescence (EL) performance relies on the sufficient carrier injection. In this work, the atomic GaO layers are inserted within the Er-doped GeO nanofilms fabricated by atomic layer deposition (ALD). Both Ga(CH) and Ga(CH) could realize the ALD growth of GaO onto the as-deposited GeO nanofilm with unaffected deposition rates.

View Article and Find Full Text PDF

The effects of diazepam on sleep depend on the photoperiod.

Acta Pharmacol Sin

January 2025

Laboratory for Neurophysiology, Department of Cell and Chemical Biology, Leiden University, Medical Centre, Leiden, 2333, ZC, The Netherlands.

Daylength (i.e., photoperiod) provides essential information for seasonal adaptations of organisms.

View Article and Find Full Text PDF

Corticospinal motor neurons (CSMN), located in the motor cortex of the brain, are one of the key components of the motor neuron circuitry. They are in part responsible for the initiation and modulation of voluntary movement, and their degeneration is the hallmark for numerous diseases, such as amyotrophic lateral sclerosis (ALS), hereditary spastic paraplegia, and primary lateral sclerosis. Cortical hyperexcitation followed by in-excitability suggests the early involvement of cortical dysfunction in ALS pathology.

View Article and Find Full Text PDF

Photodynamic antimicrobial therapy with Erythrosin B, Eosin Y, and Rose Bengal for the inhibition of fungal keratitis isolates: An in vitro study.

J Photochem Photobiol B

December 2024

Anne Bates Leach Eye Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America; Ocular Microbiology Laboratory, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America.

Introduction: Fungal keratitis is a leading cause of corneal blindness, with current antifungal treatments having limited efficacy. One promising treatment modality is Rose Bengal (RB) photodynamic antimicrobial therapy (PDAT) that has shown mixed success against fungal keratitis. Therefore, there is a need to explore the antimicrobial efficacy of other green-light activated photosensitizers that have deep penetration in the cornea to combat the deep fungal infections, such as Erythrosin B (EB) and Eosin Y (EY).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!