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1H MRS studies in the Finnish boron neutron capture therapy project: detection of 10B-carrier, L-p-boronophenylalanine-fructose.

https://arctichealth.org/en/permalink/ahliterature172386
Source
Eur J Radiol. 2005 Nov;56(2):154-9
Publication Type
Article
Date
Nov-2005
Author
M. Timonen
L. Kankaanranta
N. Lundbom
J. Collan
A. Kangasmäki
M. Kortesniemi
A-M Häkkinen
A. Lönngren
S. Karjalainen
M. Rasilainen
J. Leinonen
T. Huitti
J. Jääskeläinen
M. Kouri
S. Savolainen
S. Heikkinen
Author Affiliation
Department of Physical Sciences, University of Helsinki, POB 64, FIN-00014, Helsinki, Finland.
Source
Eur J Radiol. 2005 Nov;56(2):154-9
Date
Nov-2005
Language
English
Publication Type
Article
Keywords
Adult
Aged
Boron - therapeutic use
Boron Compounds - analysis - blood
Boron Neutron Capture Therapy
Brain Neoplasms - pathology - radiotherapy
Carcinoma - pathology - radiotherapy
Female
Finland
Fructose - analogs & derivatives - analysis - blood
Glioblastoma - pathology - radiotherapy
Humans
Hydrogen
Isotopes - therapeutic use
Magnetic Resonance Spectroscopy - methods
Male
Neoplasm Recurrence, Local - pathology - radiotherapy
Paranasal Sinus Neoplasms - pathology - radiotherapy
Phantoms, Imaging
Plasma
Radiopharmaceuticals - therapeutic use
Abstract
This article summarizes the current status of 1H MRS in detecting and quantifying a boron neutron capture therapy (BNCT) boron carrier, L-p-boronophenylalanine-fructose (BPA-F) in vivo in the Finnish BNCT project. The applicability of 1H MRS to detect BPA-F is evaluated and discussed in a typical situation with a blood containing resection cavity within the gross tumour volume (GTV). 1H MRS is not an ideal method to study BPA concentration in GTV with blood in recent resection cavity. For an optimal identification of BPA signals in the in vivo 1H MR spectrum, both pre- and post-infusion 1H MRS should be performed. The post-infusion spectroscopy studies should be scheduled either prior to or, less optimally, immediately after the BNCT. The pre-BNCT MRS is necessary in order to utilise the MRS results in the actual dose planning.
PubMed ID
16233888 View in PubMed
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The accuracy of quantitative parameters in (99m) Tc-MAG3 dynamic renography: a national audit based on virtual image data.

https://arctichealth.org/en/permalink/ahliterature277742
Source
Clin Physiol Funct Imaging. 2016 Mar;36(2):146-54
Publication Type
Article
Date
Mar-2016
Author
Gustav Brolin
Lars Edenbrandt
Göran Granerus
Anna Olsson
David Afzelius
Agneta Gustafsson
Cathrine Jonsson
Jessica Hagerman
Lena Johansson
Katrine Riklund
Michael Ljungberg
Source
Clin Physiol Funct Imaging. 2016 Mar;36(2):146-54
Date
Mar-2016
Language
English
Publication Type
Article
Keywords
Computer simulation
Feasibility Studies
Female
Gamma Cameras
Humans
Image Interpretation, Computer-Assisted
Kidney - physiopathology - radionuclide imaging
Kidney Diseases - physiopathology - radionuclide imaging
Male
Monte Carlo Method
Observer Variation
Phantoms, Imaging
Predictive value of tests
Radioisotope Renography - instrumentation - methods - standards
Radiopharmaceuticals - administration & dosage
Reproducibility of Results
Software
Sweden
Technetium Tc 99m Mertiatide - administration & dosage
Abstract
Assessment of image analysis methods and computer software used in (99m) Tc-MAG3 dynamic renography is important to ensure reliable study results and ultimately the best possible care for patients. In this work, we present a national multicentre study of the quantification accuracy in (99m) Tc-MAG3 renography, utilizing virtual dynamic scintigraphic data obtained by Monte Carlo-simulated scintillation camera imaging of digital phantoms with time-varying activity distributions. Three digital phantom studies were distributed to the participating departments, and quantitative evaluation was performed with standard clinical software according to local routines. The differential renal function (DRF) and time to maximum renal activity (Tmax ) were reported by 21 of the 28 Swedish departments performing (99m) Tc-MAG3 studies as of 2012. The reported DRF estimates showed a significantly lower precision for the phantom with impaired renal uptake than for the phantom with normal uptake. The Tmax estimates showed a similar trend, but the difference was only significant for the right kidney. There was a significant bias in the measured DRF for all phantoms caused by different positions of the left and right kidney in the anterior-posterior direction. In conclusion, this study shows that virtual scintigraphic studies are applicable for quality assurance and that there is a considerable uncertainty associated with standard quantitative parameters in dynamic (99m) Tc-MAG3 renography, especially for patients with impaired renal function.
PubMed ID
25348641 View in PubMed
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An international dosimetry exchange for BNCT part II: computational dosimetry normalizations.

https://arctichealth.org/en/permalink/ahliterature90266
Source
Med Phys. 2008 Dec;35(12):5419-25
Publication Type
Article
Date
Dec-2008
Author
Riley K J
Binns P J
Harling O K
Albritton J R
Kiger W S
Rezaei A.
Sköld K.
Seppälä T.
Savolainen S.
Auterinen I.
Marek M.
Viererbl L.
Nievaart V A
Moss R L
Author Affiliation
Nuclear Reactor Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Source
Med Phys. 2008 Dec;35(12):5419-25
Date
Dec-2008
Language
English
Publication Type
Article
Keywords
Boron - pharmacology
Boron Compounds - pharmacology
Boron Neutron Capture Therapy - methods - standards
Clinical Trials as Topic
Humans
Isotopes - pharmacology
Neoplasms - radiotherapy
Phantoms, Imaging
Phenylalanine - analogs & derivatives - pharmacology
Radiation-Sensitizing Agents - pharmacology
Radiometry - methods - statistics & numerical data
Radiotherapy Dosage
Radiotherapy Planning, Computer-Assisted - methods
Reproducibility of Results
Software
Treatment Outcome
Abstract
The meaningful sharing and combining of clinical results from different centers in the world performing boron neutron capture therapy (BNCT) requires improved precision in dose specification between programs. To this end absorbed dose normalizations were performed for the European clinical centers at the Joint Research Centre of the European Commission, Petten (The Netherlands), Nuclear Research Institute, Rez (Czech Republic), VTT, Espoo (Finland), and Studsvik, Nyköping (Sweden). Each European group prepared a treatment plan calculation that was bench-marked against Massachusetts Institute of Technology (MIT) dosimetry performed in a large, water-filled phantom to uniformly evaluate dose specifications with an estimated precision of +/-2%-3%. These normalizations were compared with those derived from an earlier exchange between Brookhaven National Laboratory (BNL) and MIT in the USA. Neglecting the uncertainties related to biological weighting factors, large variations between calculated and measured dose are apparent that depend upon the 10B uptake in tissue. Assuming a boron concentration of 15 microg g(-1) in normal tissue, differences in the evaluated maximum dose to brain for the same nominal specification of 10 Gy(w) at the different facilities range between 7.6 and 13.2 Gy(w) in the trials using boronophenylalanine (BPA) as the boron delivery compound and between 8.9 and 11.1 Gy(w) in the two boron sulfhydryl (BSH) studies. Most notably, the value for the same specified dose of 10 Gy(w) determined at the different participating centers using BPA is significantly higher than at BNL by 32% (MIT), 43% (VTT), 49% (JRC), and 74% (Studsvik). Conversion of dose specification is now possible between all active participants and should be incorporated into future multi-center patient analyses.
PubMed ID
19175101 View in PubMed
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An international dosimetry exchange for boron neutron capture therapy. Part I: Absorbed dose measurements.

https://arctichealth.org/en/permalink/ahliterature16464
Source
Med Phys. 2005 Dec;32(12):3729-36
Publication Type
Article
Date
Dec-2005
Author
P J Binns
K J Riley
O K Harling
W S Kiger
P M Munck af Rosenschöld
V. Giusti
J. Capala
K. Sköld
I. Auterinen
T. Serén
P. Kotiluoto
J. Uusi-Simola
M. Marek
L. Viererbl
F. Spurny
Author Affiliation
Nuclear Reactor Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. binns@mit.edu
Source
Med Phys. 2005 Dec;32(12):3729-36
Date
Dec-2005
Language
English
Publication Type
Article
Keywords
Biophysics
Boron Neutron Capture Therapy - standards - statistics & numerical data
Clinical Protocols
Clinical Trials - statistics & numerical data
Europe
Humans
International Cooperation
Multicenter Studies
Neoplasms - radiotherapy
Phantoms, Imaging
Radiometry - statistics & numerical data
Radiotherapy Planning, Computer-Assisted - standards - statistics & numerical data
Research Support, U.S. Gov't, Non-P.H.S.
United States
Abstract
An international collaboration was organized to undertake a dosimetry exchange to enable the future combination of clinical data from different centers conducting neutron capture therapy trials. As a first step (Part I) the dosimetry group from the Americas, represented by MIT, visited the clinical centers at Studsvik (Sweden), VTT Espoo (Finland), and the Nuclear Research Institute (NRI) at Rez (Czech Republic). A combined VTT/NRI group reciprocated with a visit to MIT. Each participant performed a series of dosimetry measurements under equivalent irradiation conditions using methods appropriate to their clinical protocols. This entailed in-air measurements and dose versus depth measurements in a large water phantom. Thermal neutron flux as well as fast neutron and photon absorbed dose rates were measured. Satisfactory agreement in determining absorbed dose within the experimental uncertainties was obtained between the different groups although the measurement uncertainties are large, ranging between 3% and 30% depending upon the dose component and the depth of measurement. To improve the precision in the specification of absorbed dose amongst the participants, the individually measured dose components were normalized to the results from a single method. Assuming a boron concentration of 15 microg g(-1) that is typical of concentrations realized clinically with the boron delivery compound boronophenylalanine-fructose, systematic discrepancies in the specification of the total biologically weighted dose of up to 10% were apparent between the different groups. The results from these measurements will be used in future to normalize treatment plan calculations between the different clinical dosimetry protocols as Part II of this study.
PubMed ID
16475772 View in PubMed
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Aortic stentgraft movement detection using digital roentgen stereophotogrammetric analysis on plane film radiographs -- initial results of a phantom study.

https://arctichealth.org/en/permalink/ahliterature176111
Source
Rofo. 2005 Mar;177(3):321-5
Publication Type
Article
Date
Mar-2005
Author
C. Georg
V. Welker
H. Eidam
H. Alfke
Author Affiliation
Department of Diagnostic Radiology, Philipps-University Marburg.
Source
Rofo. 2005 Mar;177(3):321-5
Date
Mar-2005
Language
English
Publication Type
Article
Keywords
Aorta
Aortic Aneurysm, Abdominal - surgery
Feasibility Studies
Humans
Image Processing, Computer-Assisted
Phantoms, Imaging
Photogrammetry - methods
Polymethyl Methacrylate
Prosthesis Failure
Radiography - methods
Stents
Tantalum
Abstract
To evaluate the feasibility of aortic stentgraft micromovement detection using digital roentgen stereophotogrammetric analysis on plane film radiographs.
An aortic stentgraft used for demonstration purposes was marked with 10 tantalum markers of 0.8 mm in diameter. The stentgraft was placed on a Plexiglas phantom with 5 tantalum markers of 1 mm in diameter simulating a fixed segment needed for mathematical analysis. In a subsequent step, the stentgraft was placed onto an orthopaedic spine model to simulate in vivo conditions.in a next step. Two radiographs taken simultaneously from different angles were used for simulating different stentgraft movement, e. g. translation, angulation, aortic pulsation and migration in the spine model. Movement of the stentgraft markers was analysed using a commercially available digital RSA setup (UmRSA(R) 4.1, RSA Biomedical, Umea, Sweden).
Our study shows the feasibility of measuring aortic stentgraft movement and changes in stentgraft shape in the submillimeter range using digital roentgen stereophotogrammetric analysis. Translation along the 3 cardinal axes, change in stentgraft shape, simulation of aortic pulsation and simulation of in vivo conditions could be described precisely.
Aortic stentgraft movement detection using digital roentgen stereophotogrammetric analysis on plane film radiographs is a very promising, precise method.
PubMed ID
15719292 View in PubMed
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Application of the new MultiTrans SP3 radiation transport code in BNCT dose planning.

https://arctichealth.org/en/permalink/ahliterature193070
Source
Med Phys. 2001 Sep;28(9):1905-10
Publication Type
Article
Date
Sep-2001
Author
P. Kotiluoto
P. Hiisamäki
S. Savolainen
Author Affiliation
VTT Chemical Technology, Industrial Physics, Finland. petri.kotiluoto@vtt.fi
Source
Med Phys. 2001 Sep;28(9):1905-10
Date
Sep-2001
Language
English
Publication Type
Article
Keywords
Adult
Biophysical Phenomena
Biophysics
Boron Neutron Capture Therapy
Brain Neoplasms - radiotherapy
Finland
Humans
Phantoms, Imaging
Polymethyl Methacrylate
Radiotherapy Planning, Computer-Assisted - methods - statistics & numerical data
Abstract
Dose planning in boron neutron capture therapy (BNCT) is a complex problem and requires sophisticated numerical methods. In the framework of the Finnish BNCT project, new deterministic three-dimensional radiation transport code MultiTrans SP3 has been developed at VTT Chemical Technology, based on a novel application of the tree multigrid technique. To test the applicability of this new code in a realistic BNCT dose planning problem, cylindrical PMMA (polymethyl-methacrylate) phantom was chosen as a benchmark case. It is a convenient benchmark, as it has been modeled by several different codes, including well-known DORT and MCNP. Extensive measured data also exist. In this paper, a comparison of the new MultiTrans SP3 code with other methods is presented for the PMMA phantom case. Results show that the total neutron dose rate to ICRU adult brain calculated by the MultiTrans SP3 code differs less than 4% in 2 cm depth in phantom (in thermal maximum) from the DORT calculation. Results also show that the calculated 197Au(n,gamma) and 55Mn(n,gamma) reaction rates in 2 cm depth in phantom differ less than 4% and 1% from the measured values, respectively. However, the photon dose calculated by the MultiTrans SP3 code seems to be incorrect in this PMMA phantom case, which requires further studying. As expected, the deterministic MultiTrans SP3 code is over an order of magnitude faster than stochastic Monte Carlo codes (with similar resolution), thus providing a very efficient tool for BNCT dose planning.
PubMed ID
11585221 View in PubMed
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Assessing polyp size by improved digitalized computed tomography (CT).

https://arctichealth.org/en/permalink/ahliterature85618
Source
Anticancer Res. 2008 May-Jun;28(3B):1911-5
Publication Type
Article
Author
Suzuki Chikako
Matsson Lars
Rubio Carlos A
Author Affiliation
Department of Diagnostic Radiology, Institution for Molecular Medicine and Surgery, Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden.
Source
Anticancer Res. 2008 May-Jun;28(3B):1911-5
Language
English
Publication Type
Article
Keywords
Humans
Intestinal Polyps - diagnosis - pathology
Phantoms, Imaging
Tomography, X-Ray Computed - instrumentation - methods
Abstract
BACKGROUND: The size of colorectal polyps is important in the clinical management of these lesions. When using a conventional ruler (the tool of pathologists worldwide), we have previously found unacceptably high intra- and inter-observer variations in assessing the size of phantom polyps. The aim of this study was to assess the size of 12 phantom polyps by computed tomography (CT). MATERIALS AND METHODS: The size of phantom polyps as assessed by CT was compared to the gold standard size (GSS) measured at The Royal Institute of Technology, Stockholm, Sweden. RESULTS: In 33.3% (n=4) of the 12 polyps and in 41.7% (n=25) of the 60 measurements, the mean CT size under- or overestimated the GSS by more than 1 mm. In 15%, or in 9 of the 60 measurements, the CT size was under- or overestimated by more than 2 mm. In polyp #5 the GSS size was 8.41 mm where the expected cancer-risk in adenomas is 1%. But 3 out of 5 CT measurements were >10 mm, where the expected cancer-risk in adenomas is 10%. In polyp #10 the GSS size was 10.20 mm where the expected cancer-risk is 10%. But 2 out of 5 CT measurements were
PubMed ID
18630480 View in PubMed
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Assessment of coronary calcification using calibrated mass score with two different multidetector computed tomography scanners in the Copenhagen General Population Study.

https://arctichealth.org/en/permalink/ahliterature282425
Source
Eur J Radiol. 2017 Mar;88:21-25
Publication Type
Article
Date
Mar-2017
Author
Andreas Fuchs
Jaap M Groen
Ben A Arnold
Sasho Nikolovski
Andreas D Knudsen
J Tobias Kühl
Børge G Nordestgaard
Marcel J W Greuter
Klaus F Kofoed
Source
Eur J Radiol. 2017 Mar;88:21-25
Date
Mar-2017
Language
English
Publication Type
Article
Keywords
Adult
Aged
Aged, 80 and over
Calcinosis - complications - diagnostic imaging
Calibration
Coronary Artery Disease - complications - diagnostic imaging
Denmark
Female
Humans
Male
Middle Aged
Multidetector Computed Tomography - instrumentation - methods
Phantoms, Imaging
Reproducibility of Results
Tomography Scanners, X-Ray Computed
Abstract
Population studies have shown coronary calcium score to improve risk stratification in subjects suspected for cardiovascular disease. The aim of this work was to assess the validity of multidetector computed tomography (MDCT) for measurement of calibrated mass scores (MS) in a phantom study, and to investigate inter-scanner variability for MS and Agaston score (AS) recorded in a population study on two different high-end MDCT scanners.
A calcium phantom was scanned by a first (A) and second (B) generation 320-MDCT. MS was measured for each calcium deposit from repeated measurements in each scanner and compared to known physical phantom mass. Random samples of human subjects from the Copenhagen General Population Study were scanned with scanner A (N=254) and scanner B (N=253) where MS and AS distributions of these two groups were compared.
The mean total MS of the phantom was 32.9?0.8mg and 33.1?0.9mg (p=0.43) assessed by scanner A and B respectively - the physical calcium mass was 34.0mg. Correlation between measured MS and physical calcium mass was R(2)=0.99 in both scanners. In the population study the median total MS was 16.8mg (interquartile range (IQR): 3.5-81.1) and 15.8mg (IQR: 3.8-63.4) in scanner A and B (p=0.88). The corresponding median total AS were 92 (IQR: 23-471) and 89 (IQR: 40-384) (p=0.64).
Calibrated calcium mass score may be assessed with very high accuracy in a calcium phantom by different generations of 320-MDCT scanners. In population studies, it appears acceptable to pool calcium scores acquired on different 320-MDCT scanners.
PubMed ID
28189204 View in PubMed
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Assessment of image quality and total performance in Norwegian mammography laboratories. Findings in a national survey based on different phantoms and ROC methodology.

https://arctichealth.org/en/permalink/ahliterature204436
Source
Acta Radiol. 1998 Sep;39(5):507-13
Publication Type
Article
Date
Sep-1998
Author
J B Olsen
A. Skretting
A. Widmark
Author Affiliation
Department of Medical Physics and Technology, Norwegian Radium Hospital, Montebello, Oslo, Norway.
Source
Acta Radiol. 1998 Sep;39(5):507-13
Date
Sep-1998
Language
English
Publication Type
Article
Keywords
Female
Humans
Mammography - standards
Norway
Observer Variation
Phantoms, Imaging
ROC Curve
Radiographic Image Enhancement
Abstract
To assess the image quality at different mammography laboratories.
Two commercial mammographic test phantoms and one phantom based on excised mammary tissue were used in an assessment of the imaging chain and total performance at 45 Norwegian mammography laboratories. The breast-tissue phantom was used for a receiver operating characteristics (ROC) analysis. This was carried out by putting overlays with identifiable regions (some of which contained a cluster of simulated calcifications) on top of the mammary tissue, and then having a radiologist report the confidence of a finding for each region.
The areas under the ROC curves were in general high. In nearly all the laboratories, performance was improved when a magnification technique was applied. There were wide variations among the laboratories in total performance as measured by the area under the ROC curve, and also in the physical parameters derived by means of the commercial phantoms. In general, a good ROC performance was associated with a good physical performance in the imaging chain.
PubMed ID
9755699 View in PubMed
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Bone mineral density measures in longitudinal studies: the choice of phantom is crucial for quality assessment. The Tromsø study, a population-based study.

https://arctichealth.org/en/permalink/ahliterature174851
Source
Osteoporos Int. 2005 Dec;16(12):1597-603
Publication Type
Article
Date
Dec-2005
Author
Nina Emaus
G K R Berntsen
R. Joakimsen
V. Fønnebø
Author Affiliation
Institute of Community Medicine, Faculty of medicine, University of Tromsø, 9037, Tromsø, Norway. nina.emaus@ism.uit.no
Source
Osteoporos Int. 2005 Dec;16(12):1597-603
Date
Dec-2005
Language
English
Publication Type
Article
Keywords
Absorptiometry, Photon - instrumentation - methods
Adult
Aged
Aged, 80 and over
Aluminum - analysis
Bone Density - physiology
Equipment Design
Female
Forearm
Humans
Longitudinal Studies
Male
Middle Aged
Osteoporosis - diagnosis
Phantoms, Imaging
Population Surveillance - methods
Quality Control
Abstract
Determination of change in bone mineral density (BMD) requires high-precision densitometry techniques. The purpose of the study is to investigate to what degree different densitometer phantoms reflect observed changes in human BMD and to investigate to what degree fluctuations in densitometers' measurement level influence bone loss estimates. Densitometer influence was assessed using the aluminum forearm phantom (AFP) provided by the manufacturer, the European forearm phantom (EFP) of semi-anthropomorphic calcium-hydroxyapatite, and repeated population measurements on different densitometer combinations. The mean follow-up time was 6.4 years (SD 0.6). Measured population bone loss varied from 4.6%/year to 3.2%/year, depending on densitometer combinations. These variations could not be explained by differences in sex, age, height, weight and baseline BMD. They were predicted by EFP measurements, but not AFP measurements. The EFP measurements indicate that X-ray tube replacement changed the densitometers' measurement level in one of three instances, whereas "wear and tear" did not. We used the EFP data for adjustment of the densitometers' measurement levels. After adjustment, the overall crude bone loss was reduced from 4.14% to 3.92%. Mean annual loss was reduced from 0.64% or 0.61%. We conclude that densitometer performance might influence the accuracy of bone loss estimates. Changes in performance are not detected by aluminum phantoms. Quality control of BMD measurements in longitudinal studies should be performed with anthropomorphic calcium-hydroxyapatite phantoms in order to detect possible differences between the participating densitometers' measurement levels.
PubMed ID
15886862 View in PubMed
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69 records – page 1 of 7.