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Feroz Maqbool - One of the best experts on this subject based on the ideXlab platform.
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skin entrance radiation dose in an Interventional Radiology Procedure
Health Physics, 2006Co-Authors: George Thomas, Feroz MaqboolAbstract:Abstract—Monitoring of skin entrance radiation exposure in lengthy Interventional Procedures has been recommended because of the potential for skin injury. Fluoroscopy duration and dose-area product (DAP) are readily available real-time measurements. It would be of interest to study the correlation
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skin entrance radiation dose in an Interventional Radiology Procedure
Health Physics, 2006Co-Authors: Robert Y L Chu, George Thomas, Feroz MaqboolAbstract:Monitoring of skin entrance radiation exposure in lengthy Interventional Procedures has been recommended because of the potential for skin injury. Fluoroscopy duration and dose-area product (DAP) are readily available real-time measurements. It would be of interest to study the correlation of these parameters and skin entrance radiation. Twenty neurological Interventional Procedures performed through the aortic arch were monitored. Two pieces of GafChromic XR Type R film were placed between the patient and the examination table. An observer recorded the fluoroscopy duration and DAP for each phase of the Procedure. Each film was scanned post-Procedure in RBG mode, and then the image was analyzed for peak skin entrance radiation dose (in air kerma). All DAP values were corrected according to a calibration with an ion chamber. With the DAP values for the respective phases of a Procedure, the effective dose in a Reference Man was calculated. For these twenty cases, the means and standard deviations were 17.2+/-6.4 min for x ray on-time, 256+/-65 Gy cm (-2) for DAP, 94+/-34 cGy for peak skin entrance dose in air kerma, and 19.2+/-5.0 mSv for effective dose, respectively. The peak skin entrance dose was correlated to fluoroscopy duration, DAP, and effective dose with the r(2)-values of 0.48, 0.46, and 0.09, respectively. The correlation with DAP or fluoroscopy duration was not sufficiently strong to infer skin entrance dose from either of these parameters. Therefore, skin entrance dose should be determined directly.
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su ff i 19 skin entrance radiation dose in an Interventional Radiology Procedure
Medical Physics, 2005Co-Authors: Robert Y L Chu, George Thomas, Feroz MaqboolAbstract:Purpose: Monitoring of skin entrance radiation exposure in lengthy Interventional Procedures with X‐ray is recommended because of the potential for skin injury. X‐ray on‐time and dose‐area product (DAP) are readily available real‐time measurements. It would be of interest to study the correlation of these parameters and skin entrance radiation. Method and Materials: Twenty Interventional Procedures performed through the aortic arch to one or more of its three associated major blood vessels were monitored. Two pieces of GafChromic XR Type R film were placed between the patient and the examination table. An observer recorded the X‐ray on‐time and DAP for each phase of the Procedure. Each film was scanned post‐Procedure in RBG mode, and then the red component of the image was analyzed for peak skin entrance radiation dose (in air kerma) after proper calibration. All DAP values were corrected according to a calibration with an ion chamber. With the corrected DAP values for the respective phases of a Procedure, and the Monte Carlo model used by the National Radiological Protection Board (United Kingdom), the effective dose in a standard man was calculated. Results: For these twenty cases, the mean and standard deviation of were 17.2 ± 6.4 minutes for X‐ray on‐time, 256 ± 65 Gy.cm2 for DAP, 94 ± 34 cGy for peak skin entrance dose in air kerma, and 13.2 ± 3.1 mSv for effective dose. The peak skin entrance dose was correlated to X‐ray on‐time, DAP and effective dose with the coefficients of 0.69, 0.68, and 0.49 respectively. The corresponding r‐values in linear regression analysis were 0.48, 0.46, and 0.24. Conclusion: The poor correlation with DAP and X‐ray on‐time suggests that skindose should be measured independently. However, peak skin entrance dose would be a poor indicator for effective dose. Determination of the latter requires more detail information.
Robert Y L Chu - One of the best experts on this subject based on the ideXlab platform.
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skin entrance radiation dose in an Interventional Radiology Procedure
Health Physics, 2006Co-Authors: Robert Y L Chu, George Thomas, Feroz MaqboolAbstract:Monitoring of skin entrance radiation exposure in lengthy Interventional Procedures has been recommended because of the potential for skin injury. Fluoroscopy duration and dose-area product (DAP) are readily available real-time measurements. It would be of interest to study the correlation of these parameters and skin entrance radiation. Twenty neurological Interventional Procedures performed through the aortic arch were monitored. Two pieces of GafChromic XR Type R film were placed between the patient and the examination table. An observer recorded the fluoroscopy duration and DAP for each phase of the Procedure. Each film was scanned post-Procedure in RBG mode, and then the image was analyzed for peak skin entrance radiation dose (in air kerma). All DAP values were corrected according to a calibration with an ion chamber. With the DAP values for the respective phases of a Procedure, the effective dose in a Reference Man was calculated. For these twenty cases, the means and standard deviations were 17.2+/-6.4 min for x ray on-time, 256+/-65 Gy cm (-2) for DAP, 94+/-34 cGy for peak skin entrance dose in air kerma, and 19.2+/-5.0 mSv for effective dose, respectively. The peak skin entrance dose was correlated to fluoroscopy duration, DAP, and effective dose with the r(2)-values of 0.48, 0.46, and 0.09, respectively. The correlation with DAP or fluoroscopy duration was not sufficiently strong to infer skin entrance dose from either of these parameters. Therefore, skin entrance dose should be determined directly.
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su ff i 19 skin entrance radiation dose in an Interventional Radiology Procedure
Medical Physics, 2005Co-Authors: Robert Y L Chu, George Thomas, Feroz MaqboolAbstract:Purpose: Monitoring of skin entrance radiation exposure in lengthy Interventional Procedures with X‐ray is recommended because of the potential for skin injury. X‐ray on‐time and dose‐area product (DAP) are readily available real‐time measurements. It would be of interest to study the correlation of these parameters and skin entrance radiation. Method and Materials: Twenty Interventional Procedures performed through the aortic arch to one or more of its three associated major blood vessels were monitored. Two pieces of GafChromic XR Type R film were placed between the patient and the examination table. An observer recorded the X‐ray on‐time and DAP for each phase of the Procedure. Each film was scanned post‐Procedure in RBG mode, and then the red component of the image was analyzed for peak skin entrance radiation dose (in air kerma) after proper calibration. All DAP values were corrected according to a calibration with an ion chamber. With the corrected DAP values for the respective phases of a Procedure, and the Monte Carlo model used by the National Radiological Protection Board (United Kingdom), the effective dose in a standard man was calculated. Results: For these twenty cases, the mean and standard deviation of were 17.2 ± 6.4 minutes for X‐ray on‐time, 256 ± 65 Gy.cm2 for DAP, 94 ± 34 cGy for peak skin entrance dose in air kerma, and 13.2 ± 3.1 mSv for effective dose. The peak skin entrance dose was correlated to X‐ray on‐time, DAP and effective dose with the coefficients of 0.69, 0.68, and 0.49 respectively. The corresponding r‐values in linear regression analysis were 0.48, 0.46, and 0.24. Conclusion: The poor correlation with DAP and X‐ray on‐time suggests that skindose should be measured independently. However, peak skin entrance dose would be a poor indicator for effective dose. Determination of the latter requires more detail information.
A Torresin - One of the best experts on this subject based on the ideXlab platform.
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104 use of a rdim system to analyse and optimize an Interventional Radiology Procedure
Physica Medica, 2018Co-Authors: P E Colombo, C De Mattia, Federica Rottoli, M Sutto, Antonio Rampoldi, F Barbosa, A TorresinAbstract:Purpose To use NEXO[DOSE], a Radiation Dose Index Monitoring system, to collect and analyse dosimetric data to drive the optimization of the Interventional Radiology Procedure for prostatic artery embolization (PAE). Methods NEXO[DOSE] extracts geometric (primary and secondary angles, table height) and dosimetric (irradiation type, KAP, voltage, filter) parameters from the Radiation Dose Structured Report, and calculates a skin dose map. NEXO[DOSE] separately lists the dose contribution from the acquisition mode and the fluoroscopy. In our institution, the PAE Interventional Procedure involved high Kerma Area Product (KAP) compared to other angiographic protocols and was associated with high risk of skin lesions. A low dose protocol was introduced and phantom characterization, i.e. entrance dose and image quality (LCD), was assessed on 24 to 30 cm PMMA phantom to better represent the patient geometry, considering that the highest dose contributions came from events with oblique angles. After optimization, patient dose was monitored using KAP and peak skin dose. Results We retrospectively analysed the exposure values of 84 patients, using NEXO[DOSE]. The acquisition dose in PAE is 70% of the total Procedure: the first step was the introduction of an acquisition protocol with low entrance detector dose. The frame rate was reduced from 3 to 2 fps, and additional X-ray filtration of 1 mmAl + 0.1 mmCu was added. The fluoroscopy frame rate was also reduced from 15 to 7.5 fps. Entrance dose at the phantom surface was reduced by 49%, while the LCD reduction was 30% for details dimensions from 0.5 to 6 mm. The physicians assessed the loss of image quality to be acceptable. After optimization PAE Procedures showed a 60% KAP reduction and a 49% peak skin dose reduction. Conclusions A RDIM software is a useful tool to highlight high dose Procedures and to understand what parameters to modify, after a multidisciplinary team discussion.
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p021 analysis and optimization of an Interventional Radiology Procedure using a radiation dose index monitoring software
Physica Medica, 2018Co-Authors: P E Colombo, C De Mattia, Federica Rottoli, M Sutto, Antonio Rampoldi, A TorresinAbstract:Purpose To use NEXO[DOSE]; a Radiation Dose Index Monitoring system, to collect and analyse dosimetric data to drive the optimization of Interventional Radiology Procedure for prostatic artery embolization (PAE). Methods NEXO[DOSE] extracts geometric (primary and secondary angles, table height) and dosimetric (irradiation type, KAP, voltage, filter) parameters from the Radiation Dose Structured Report, and calculates a skin dose map. This software separately lists the dose contribution from the acquisition mode and the fluoroscopy: this can help to quantify the contribution of the two acquisition types. We identify in our institution the PAE angiographic Procedure as a high dose Procedure, with high Kerma Area Product (KAP) compared to other Interventional protocols. It was associated with high risk of skin lesions. A low dose protocol was introduced and phantom characterization, i.e. entrance dose and image quality (LCD), was assessed on various thickness of PMMA. It was necessary to use 30 cm of PMMA to better represent the patient geometry, considering that, in this Procedure, the highest dose contributions came from events with oblique angles. After optimization, patient dose was monitored using KAP and peak skin dose. Results We retrospectively analysed the exposure values of 84 patients, using NEXO[DOSE]. The acquisition dose in PAE is 70% of the total Procedure: the first step was the introduction of an acquisition protocol with low entrance detector dose. The frame rate was reduced from 3 to 2 fps and additional X-ray filtration of 1 mm Al + 0.1 mm Cu was added. The fluoroscopy frame rate was also reduced from 15 to 7.5 fps. In the phantom the entrance dose was reduced by 49% and the LCD reduction was 30% for details dimensions from 0.5 to 6 mm. The physicians assessed the loss of image quality to be acceptable. The clinical Procedures had a 60% KAP reduction and a 49% PSD reduction. Conclusion The optimization process of PAE Procedure led to a significant reduction of patient dose and a degradation of image quality that was judged satisfactory from physicians. This was the result of a multidisciplinary team work (physicians, technicians and medical physicists).
George Thomas - One of the best experts on this subject based on the ideXlab platform.
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skin entrance radiation dose in an Interventional Radiology Procedure
Health Physics, 2006Co-Authors: George Thomas, Feroz MaqboolAbstract:Abstract—Monitoring of skin entrance radiation exposure in lengthy Interventional Procedures has been recommended because of the potential for skin injury. Fluoroscopy duration and dose-area product (DAP) are readily available real-time measurements. It would be of interest to study the correlation
-
skin entrance radiation dose in an Interventional Radiology Procedure
Health Physics, 2006Co-Authors: Robert Y L Chu, George Thomas, Feroz MaqboolAbstract:Monitoring of skin entrance radiation exposure in lengthy Interventional Procedures has been recommended because of the potential for skin injury. Fluoroscopy duration and dose-area product (DAP) are readily available real-time measurements. It would be of interest to study the correlation of these parameters and skin entrance radiation. Twenty neurological Interventional Procedures performed through the aortic arch were monitored. Two pieces of GafChromic XR Type R film were placed between the patient and the examination table. An observer recorded the fluoroscopy duration and DAP for each phase of the Procedure. Each film was scanned post-Procedure in RBG mode, and then the image was analyzed for peak skin entrance radiation dose (in air kerma). All DAP values were corrected according to a calibration with an ion chamber. With the DAP values for the respective phases of a Procedure, the effective dose in a Reference Man was calculated. For these twenty cases, the means and standard deviations were 17.2+/-6.4 min for x ray on-time, 256+/-65 Gy cm (-2) for DAP, 94+/-34 cGy for peak skin entrance dose in air kerma, and 19.2+/-5.0 mSv for effective dose, respectively. The peak skin entrance dose was correlated to fluoroscopy duration, DAP, and effective dose with the r(2)-values of 0.48, 0.46, and 0.09, respectively. The correlation with DAP or fluoroscopy duration was not sufficiently strong to infer skin entrance dose from either of these parameters. Therefore, skin entrance dose should be determined directly.
-
su ff i 19 skin entrance radiation dose in an Interventional Radiology Procedure
Medical Physics, 2005Co-Authors: Robert Y L Chu, George Thomas, Feroz MaqboolAbstract:Purpose: Monitoring of skin entrance radiation exposure in lengthy Interventional Procedures with X‐ray is recommended because of the potential for skin injury. X‐ray on‐time and dose‐area product (DAP) are readily available real‐time measurements. It would be of interest to study the correlation of these parameters and skin entrance radiation. Method and Materials: Twenty Interventional Procedures performed through the aortic arch to one or more of its three associated major blood vessels were monitored. Two pieces of GafChromic XR Type R film were placed between the patient and the examination table. An observer recorded the X‐ray on‐time and DAP for each phase of the Procedure. Each film was scanned post‐Procedure in RBG mode, and then the red component of the image was analyzed for peak skin entrance radiation dose (in air kerma) after proper calibration. All DAP values were corrected according to a calibration with an ion chamber. With the corrected DAP values for the respective phases of a Procedure, and the Monte Carlo model used by the National Radiological Protection Board (United Kingdom), the effective dose in a standard man was calculated. Results: For these twenty cases, the mean and standard deviation of were 17.2 ± 6.4 minutes for X‐ray on‐time, 256 ± 65 Gy.cm2 for DAP, 94 ± 34 cGy for peak skin entrance dose in air kerma, and 13.2 ± 3.1 mSv for effective dose. The peak skin entrance dose was correlated to X‐ray on‐time, DAP and effective dose with the coefficients of 0.69, 0.68, and 0.49 respectively. The corresponding r‐values in linear regression analysis were 0.48, 0.46, and 0.24. Conclusion: The poor correlation with DAP and X‐ray on‐time suggests that skindose should be measured independently. However, peak skin entrance dose would be a poor indicator for effective dose. Determination of the latter requires more detail information.
P E Colombo - One of the best experts on this subject based on the ideXlab platform.
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104 use of a rdim system to analyse and optimize an Interventional Radiology Procedure
Physica Medica, 2018Co-Authors: P E Colombo, C De Mattia, Federica Rottoli, M Sutto, Antonio Rampoldi, F Barbosa, A TorresinAbstract:Purpose To use NEXO[DOSE], a Radiation Dose Index Monitoring system, to collect and analyse dosimetric data to drive the optimization of the Interventional Radiology Procedure for prostatic artery embolization (PAE). Methods NEXO[DOSE] extracts geometric (primary and secondary angles, table height) and dosimetric (irradiation type, KAP, voltage, filter) parameters from the Radiation Dose Structured Report, and calculates a skin dose map. NEXO[DOSE] separately lists the dose contribution from the acquisition mode and the fluoroscopy. In our institution, the PAE Interventional Procedure involved high Kerma Area Product (KAP) compared to other angiographic protocols and was associated with high risk of skin lesions. A low dose protocol was introduced and phantom characterization, i.e. entrance dose and image quality (LCD), was assessed on 24 to 30 cm PMMA phantom to better represent the patient geometry, considering that the highest dose contributions came from events with oblique angles. After optimization, patient dose was monitored using KAP and peak skin dose. Results We retrospectively analysed the exposure values of 84 patients, using NEXO[DOSE]. The acquisition dose in PAE is 70% of the total Procedure: the first step was the introduction of an acquisition protocol with low entrance detector dose. The frame rate was reduced from 3 to 2 fps, and additional X-ray filtration of 1 mmAl + 0.1 mmCu was added. The fluoroscopy frame rate was also reduced from 15 to 7.5 fps. Entrance dose at the phantom surface was reduced by 49%, while the LCD reduction was 30% for details dimensions from 0.5 to 6 mm. The physicians assessed the loss of image quality to be acceptable. After optimization PAE Procedures showed a 60% KAP reduction and a 49% peak skin dose reduction. Conclusions A RDIM software is a useful tool to highlight high dose Procedures and to understand what parameters to modify, after a multidisciplinary team discussion.
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p021 analysis and optimization of an Interventional Radiology Procedure using a radiation dose index monitoring software
Physica Medica, 2018Co-Authors: P E Colombo, C De Mattia, Federica Rottoli, M Sutto, Antonio Rampoldi, A TorresinAbstract:Purpose To use NEXO[DOSE]; a Radiation Dose Index Monitoring system, to collect and analyse dosimetric data to drive the optimization of Interventional Radiology Procedure for prostatic artery embolization (PAE). Methods NEXO[DOSE] extracts geometric (primary and secondary angles, table height) and dosimetric (irradiation type, KAP, voltage, filter) parameters from the Radiation Dose Structured Report, and calculates a skin dose map. This software separately lists the dose contribution from the acquisition mode and the fluoroscopy: this can help to quantify the contribution of the two acquisition types. We identify in our institution the PAE angiographic Procedure as a high dose Procedure, with high Kerma Area Product (KAP) compared to other Interventional protocols. It was associated with high risk of skin lesions. A low dose protocol was introduced and phantom characterization, i.e. entrance dose and image quality (LCD), was assessed on various thickness of PMMA. It was necessary to use 30 cm of PMMA to better represent the patient geometry, considering that, in this Procedure, the highest dose contributions came from events with oblique angles. After optimization, patient dose was monitored using KAP and peak skin dose. Results We retrospectively analysed the exposure values of 84 patients, using NEXO[DOSE]. The acquisition dose in PAE is 70% of the total Procedure: the first step was the introduction of an acquisition protocol with low entrance detector dose. The frame rate was reduced from 3 to 2 fps and additional X-ray filtration of 1 mm Al + 0.1 mm Cu was added. The fluoroscopy frame rate was also reduced from 15 to 7.5 fps. In the phantom the entrance dose was reduced by 49% and the LCD reduction was 30% for details dimensions from 0.5 to 6 mm. The physicians assessed the loss of image quality to be acceptable. The clinical Procedures had a 60% KAP reduction and a 49% PSD reduction. Conclusion The optimization process of PAE Procedure led to a significant reduction of patient dose and a degradation of image quality that was judged satisfactory from physicians. This was the result of a multidisciplinary team work (physicians, technicians and medical physicists).
