scholarly journals Application of alanine dosimetry in dose assessment for ocular melanoma patients undergoing proton radiotherapy – preliminary results

Nukleonika ◽  
2015 ◽  
Vol 60 (3) ◽  
pp. 609-613
Author(s):  
Gabriela Mierzwińska ◽  
Magdalena Kłodowska ◽  
Barbara Michalec ◽  
Anna Pędracka ◽  
Marzena Rydygier ◽  
...  
Keyword(s):  
Nuclear Physics ◽  
Cumulative Record ◽  
Dose Assessment ◽  
Proton Radiotherapy ◽  
Quality Assurance Procedure ◽  
Solid State Electron ◽  
Paramagnetic Resonance ◽  
Entrance Dose ◽  
Ocular Cancer ◽  
Dose Measurements

Abstract Basing on alanine solid state/electron paramagnetic resonance (EPR) dosimetry, a supplementary method of cumulatively recording the therapeutic dose received by ocular cancer patients undergoing fractionated proton radiotherapy is proposed. By applying alanine dosimetry during the delivery of consecutive fractions, the dose received within each fraction can be read out by EPR spectrometry and a final permanent cumulative record of the total dose delivered obtained. The dose response of the alanine detector was found to be practically independent on its position within the extended proton Bragg peak region. Dose measurements based on entrance dose recorded in proton beams individually formed for each patient are presented. The described method will be applied as a complementary Quality Assurance procedure for patients undergoing proton radiotherapy at the Institute of Nuclear Physics, Polish Academy of Sciences, Krakow, Poland (IFJ PAN).

OSL films for in-vivo entrance dose measurements

2017 ◽  
Vol 106 ◽  
pp. 644-649 ◽  
Author(s):  
S.O. Souza ◽  
F. d'Errico ◽  
B. Azimi ◽  
A. Baldassare ◽  
A.V.S. Alves ◽  
...  
Keyword(s):  
Entrance Dose ◽  
Dose Measurements

Systematic in vivo dosimetry for quality assurance using diodes 2: Assessing radiotherapy techniques and developing an appropriate action protocol

2004 ◽  
Vol 4 (4) ◽  
pp. 143-154 ◽  
Author(s):  
R. Appleyard ◽  
K. Ball ◽  
F. E. Hughes ◽  
W. Kilby ◽  
R. Nicholls ◽  
...  
Keyword(s):  
Head And Neck ◽  
In Vivo Dosimetry ◽  
Entrance Dose ◽  
Treatment Category ◽  
P Type ◽  
Dose Measurements ◽  
Action Levels

Purpose: Having previously reviewed the implementation of systematic in vivo dosimetry at the Norfolk and Norwich Hospital this paper examines the results of entrance dose measurements for specific sites/techniques and determines whether different action/alert protocols are required for these different categories.Methods and materials: Entrance dose measurements using p-type diodes were analysed for the following treatment categories: Breast, head and neck in beam direction shell, abdomino-pelvic and intrathoracic. A 4% tolerance was applied.Results: Mean deviations from expected dose and proportion of measurements exceeding tolerance were: Breast: +1.15%±3.04% (1SD), 238/1073≥4%; Head and neck: +0.35%±2.20% (1SD), 21/326≥4%; Abdomino-pelvic: +0.52%±2.75% (1SD), 93/712≥4%; Intrathoracic: −0.01%±2.75% (1SD), 22/119≥4%. Significant improvements in results for breast patients were noted following the introduction of a commercial breast board. The results for abdomino-pelvic patients confirmed a substantial variation in diode response under short FSD, wedged fields at 16MV (that had not been corrected for). The statistical uncertainty in dose measurement for each treatment category was calculated in order to assist determination of appropriate tolerance levels.Conclusions: A blanket tolerance of 4% was generally too low given the extent of measurement uncertainty. The relatively high number of readings outside tolerance where identification of errors was difficult/impossible resulted in inconsistent application of the action protocol. Some widening of tolerances is likely to improve quality of procedure and treatment. Appropriate action levels are recommended for each treatment category.

MO-F-BRA-03: Secondary Neutron Dose Measurements Using CR-39 Detectors in Photon and Proton Radiotherapy

2011 ◽  
Vol 38 (6Part26) ◽  
pp. 3721-3721
Author(s):  
R A Hälg ◽  
J Besserer ◽  
S Mayer ◽  
U Schneider
Keyword(s):  
Neutron Dose ◽  
Proton Radiotherapy ◽  
Secondary Neutron ◽  
Dose Measurements ◽  
Cr 39 Detectors

Entrance Dose Measurements on Patients and Their Relation to Organ Doses

1992 ◽  
Vol 43 (1-4) ◽  
pp. 161-163
Author(s):  
F.E. Stieve ◽  
M. Zankl ◽  
U. Nahrstedt ◽  
A. Kühnel ◽  
S. Schult
Keyword(s):  
Organ Doses ◽  
Entrance Dose ◽  
Dose Measurements

HOW MANY DOSEMETERS ARE NEEDED FOR CORRECT MEAN ORGAN DOSE ASSESSMENT WHEN PERFOMING PHANTOM DOSIMETRY? A PHANTOM STUDY EVALUATING LIVER ORGAN DOSE AND INVESTIGATING TLD NUMBERS AND WAYS OF DOSEMETER PLACEMENT

2020 ◽  
Vol 189 (4) ◽  
pp. 475-488
Author(s):  
Peter H Pedersen ◽  
Asger G Petersen ◽  
Svend E Ostgaard ◽  
Torben Tvedebrink ◽  
Søren P Eiskjær
Keyword(s):  
Statistical Difference ◽  
Handling Time ◽  
Statistical Modelling ◽  
Organ Dose ◽  
Dose Assessment ◽  
Organ Doses ◽  
X Ray ◽  
Linear Effect ◽  
Organ Specific ◽  
Dose Measurements

Abstract This study evaluated repeated mean organ dose measurements of the liver by phantom dosimetry and statistical modelling in order to find a way to reduce the number of dosemeters needed for precise organ dose measurements. Thermoluminescent dosemeters were used in an adult female phantom exposed to a biplanar x-ray source at three different axial phantom rotations. Generalised mixed linear effect modelling was used for statistical analysis. A subgroup of five to six organ-specific locations out of 28 yielded mean liver organ doses within 95% confidence intervals of measurements based on all 28 liver-specific dosemeter locations. No statistical difference of mean liver dose was observed with rotation of the phantom either 10° clockwise or counter-clockwise as opposed to the coronal plane. Phantom dosimetry handling time during organ dose measurements can be markedly reduced, in this case the liver, by 79% (22/28), while still providing precise mean organ dose measurements.

Amber Chest Radiography and Patient Dose Measurements

1995 ◽  
Vol 36 (4-6) ◽  
pp. 641-643
Author(s):  
J. Persliden ◽  
S.-G. Fransson
Keyword(s):  
Radiation Dose ◽  
Chest Radiography ◽  
Patient Dose ◽  
Chest Imaging ◽  
Entrance Dose ◽  
Thermoluminescence Dosimetry ◽  
Lower Lung ◽  
The Mean ◽  
Dose Measurements ◽  
Patient Radiation Dose

Purpose: Improved chest imaging has been reported with the usage of AMBER (advanced multiple-beam equalization radiography) equipment but with a higher patient radiation dose compared with conventional chest radiography. Most studies, however, describe dose measurements from phantoms. This study presents a comparison of radiation dose measurements in 57 patients for p.a. projections from an AMBER unit with and without an extra Cu filtration and from a formerly used conventional Siemens chest stand. Material and Methods: Dose measurements were performed with thermoluminescence dosimetry. Entrance surface doses were recorded from 5 dosimeters, placed on the patient's back. Four were placed over the upper and lower lung fields, respectively, and 1 over the mediastinal area. The dose values were then compared with the values obtained from the conventional chest stand and from the measurements with the extra filtration on the AMBER system. Results: The mean entrance dose for the mediastinal area was 0.25 mSv (range 0.15–0.49). With the extra Cu filtration it was 0.16 mSv (0.07–0.29). For the lung fields the values were 0.19 mSv (0.07–0.44) and 0.10 mSv (0.02–0.31), respectively. For the conventional chest stand the entrance dose to the patient was 0.23 mSv. Conclusion: AMBER entrance surface doses for the p.a. projection without extra Cu filtration were comparable to the doses obtained with the formerly conventional Siemens chest stand and were well within European recommendations. With extra Cu filtration the AMBER entrance surface doses were reduced by a factor of almost 2.

Build-up modification of commercial diodes for entrance dose measurements in ‘higher energy’ photon beams

1999 ◽  
Vol 51 (3) ◽  
pp. 249-256 ◽  
Author(s):  
Dietmar Georg ◽  
Bie De Ost ◽  
Marie-Thérèse Hoornaert ◽  
Pierre Pilette ◽  
Jan Van Dam ◽  
...  
Keyword(s):  
Photon Beams ◽  
Energy Photon ◽  
Entrance Dose ◽  
Dose Measurements
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