Blurred images in Full Field Digital Mammography (FFDM) are a problem in the UK Breast Screening ... more Blurred images in Full Field Digital Mammography (FFDM) are a problem in the UK Breast Screening Programme. Technical recalls may be due to blurring not being seen on lower resolution monitors used for review. This study assesses the visual detection of blurring on a 2.3 megapixel (MP) monitor and a 5 MP report grade monitor and proposes an observer standard for the visual detection of blurring on a 5 MP reporting grade monitor. Twenty-eight observers assessed 120 images for blurring; 20 had no blurring present whilst 100 had blurring imposed through mathematical simulation at 0.2, 0.4, 0.6, 0.8 and 1.0 mm levels of motion. Technical recall rate for both monitors and angular size at each level of motion were calculated. Chi-squared (X(2)) tests were used to test whether significant differences in blurring detection existed between 2.3 and 5 MP monitors. The technical recall rate for 2.3 and 5 MP monitors are 20.3 % and 9.1% respectively. Angular size for 0.2 to 1 mm motion varied fr...
Comparative analysis of radiation dose and low contrast detail detectability using routine paedia... more Comparative analysis of radiation dose and low contrast detail detectability using routine paediatric chest radiography protocols Objectives: To compare low contrast detail (LCD) detectability and radiation dose for routine paediatric chest X-ray (CXR) imaging protocols among various hospitals. Methods: CDRAD 2.0 phantom and medical grade polymethyl methacrylate (PMMA) slabs were used to simulate the chest region of four different paediatric age groups. Radiographic acquisitions were undertaken on 17 X-ray machines located in eight hospitals using their existing CXR protocols. LCD detectability represented by image quality figure inverse (IQFinv) was measured physically using the CDRAD analyser software. Incident air kerma (IAK) measurements were obtained using a solid-state dosimeter. Results: The range of IQFinv, between and within the hospitals, was 1.40-4.44 and 1.52-2.18, respectively for neonates; 0.
Fo r m o r e info r m a tio n, in cl u di n g o u r p olicy a n d s u b mi s sio n p r o c e d u ... more Fo r m o r e info r m a tio n, in cl u di n g o u r p olicy a n d s u b mi s sio n p r o c e d u r e , pl e a s e c o n t a c t t h e R e p o si to ry Te a m a t: u si r@ s alfo r d. a c. u k. Research Informed Teaching Experience in Diagnostic Radiography: Perspectives of Academic Tutors and Clinical Placement Educators Introduction: This small scale qualitative research study investigated the perceptions by both academic tutors and clinical placement educators of integrating the research-informed teaching experience (RiTe) within an undergraduate radiography curriculum to support the learning and practice of image quality and dose optimisation. Method: A purposeful sampling approach was used to recruit participants and two asynchronous on-line focus groups (OFG) were used for data collection. An inductive thematic approach was taken to analyse both sets of OFG data. Results and discussion: Five academic tutors and 4 clinical placement educators participated in the research. Three overarching themes common to both sets of OFG data were identified. Findings confirmed that both OFGs felt that the Research-informed Teaching experience (RiTe) supported student learning of image quality and dose optimisation as well as the development of research skills. However, the clinical placement educators did identify that students may find it difficult to transfer and apply this knowledge into practice (theory-practice gap). Conclusion: Results from both OFGs support RiTe with regard to the teaching and practice of image quality and dose optimisation. However, greater involvement by clinical placement educators may help to overcome issues with the translation of RiTe by students into the clinical environment (theory-practice gap) and support its continued development within the curriculum. It was also identified that RiTe could be developed for qualified staff for continued professional development (CPD).
The most effective method of detecting breast cancer amongst asymptomatic women is by mammography... more The most effective method of detecting breast cancer amongst asymptomatic women is by mammography screening. Although, most countries have this preventive measure in place for women within their society; most of these programmes still struggle with women's attendance. This article discusses four health behavioural theories and models, in relation to mammography screening, including the health belief model, theory of planned behaviour, trans-theoretical model, and the theory of care seeking behaviour that may explain the factors affecting women's participation in mammography screening. In summary, analysis of these theories indicates that the theory of care seeking behaviour has value for exploring the factors affecting women's participation in mammography screening. This is because of its sensitivity to socioeconomic differences that exists amongst women in the society, and that it has a broader construct (such as habit and external factors) compared to the other health behavioural theories.
Ti t l e O p e r a t o r e y e d o s e s d u ri n g c o m p u t e d t o m o g r a p h y fluo r o ... more Ti t l e O p e r a t o r e y e d o s e s d u ri n g c o m p u t e d t o m o g r a p h y fluo r o s c o pic lu n g bio p sy
Detection of breast cancer is reliant on optimal breast positioning and the production of quality... more Detection of breast cancer is reliant on optimal breast positioning and the production of quality images. Two projections, the mediolateral oblique and craniocaudal (CC), are routinely performed. Determination of successful positioning and inclusion of all breast tissue is achieved through meeting stated image quality criteria. For the CC view, current image quality criteria are inconsistent. Absence of reliable anatomical markers, other than the nipple, further contribute to difficulties in assessing the quality of CC views. The aim of this paper was to explore published international quality standards to identify and find the origin of any CC positioning criteria which might provide for quantitative assessment. The pectoralis major (pectoral) muscle was identified as a key posterior anatomical structure to establish optimum breast tissue inclusion on mammographic projections. It forms the first two of the three main CC metrics that are frequently reported (1) visualization of the ...
Journal of medical radiation sciences, Jan 26, 2017
Within the professions of radiation therapy and medical imaging, clinician led research activity ... more Within the professions of radiation therapy and medical imaging, clinician led research activity is becoming more prevalent. However, more is needed. A key component of continuing to develop professional groups who are both research active and producing high quality clinical research, is research mentoring. The authors of this paper share a common interest in enhancing research capacity through research mentoring within the health workforce, and came together to run a workshop on this issue at the 11th Annual Scientific Meeting of Medical Imaging and Radiation Therapy (ASMMIRT 2016) conference in Brisbane. Theory, clinical insights and issues regarding research mentoring were raised in the workshop as were the benefits of having dedicated research positions embedded within the health workforce to help provide support and build capacity. Key elements from this workshop are shared within this article, with the objective to encourage clinicians and clinical researchers to invest the ti...
Since the introduction of full field digital mammography (FFDM) a large number of UK breast cance... more Since the introduction of full field digital mammography (FFDM) a large number of UK breast cancer screening centers have reported blurred images, which can be caused by movement at the compression paddle during image acquisition. To propose and investigate the use of position feedback from the breast side of the compression paddle to reduce the settling time of breast side motion. Movement at the breast side of the paddle was measured using two calibrated linear potentiometers. A mathematical model for the compression paddle, machine drive, and breast was developed using the paddle movement data. Simulation software was used to optimize the position feedback controller parameters for different machine drive time constants and simulate the potential performance of the proposed system. The results obtained are based on simulation alone and indicate that closed-loop control of breast side paddle position dramatically reduced the settling time from over 90 s to less than 4 s. The effec...
Motion blur is a known phenomenon in full-field digital mammography, but the impact on lesion det... more Motion blur is a known phenomenon in full-field digital mammography, but the impact on lesion detection is unknown. This is the first study to investigate detection performance with varying magnitudes of simulated motion blur. Seven observers (15±5 years' reporting experience) evaluated 248 cases (62 containing malignant masses, 62 containing malignant microcalcifications and 124 normal cases) for three conditions: no blurring (0 mm) and two magnitudes of simulated blurring (0.7 mm and 1.5 mm). Abnormal cases were biopsy proven. Mathematical simulation was used to provide a pixel shift in order to simulate motion blur. A free-response observer study was conducted to compare lesion detection performance for the three conditions. The equally weighted jackknife alternative free-response receiver operating characteristic (wJAFROC) was used as the figure of merit. Test alpha was set at 0.05 to control probability of Type I error. wJAFROC analysis found a statistically significant dif...
Compression is used in mammography to reduce breast thickness, which is claimed to improve image ... more Compression is used in mammography to reduce breast thickness, which is claimed to improve image quality and reduce radiation dose. In the XXX Breast Cancer Screening Program (XBCSP), the recommended range of compression force for full field digital mammography is 11-18 kg (108-177 Newton [N]). This is the first study to investigate the compression force used in the program. The study included information from 17,951 randomly selected women screened with FFDM at 14 breast centres in the XBCSP, January-March 2014. We investigated the applied compression force on left breast in craniocaudal (CC) and mediolateral oblique (MLO) view for breast centres, mammography machines within the breast centres and for the radiographers. The mean compression force for all mammograms in the study was 116N and ranged from 91 to 147N between the breast centres. The variation in compression force was wider between the breast centres than between mammography machines (range 137-155N) and radiographers (9...
Incidental findings are common in medical imaging. There is a particularly high prevalence of inc... more Incidental findings are common in medical imaging. There is a particularly high prevalence of incidental findings within the thorax, the most frequent being pulmonary nodules. Although pulmonary nodules have the potential to be malignant, most are benign, resulting in a high number of false-positive findings. Low-resolution CT images produced for attenuation correction of SPECT images are essentially a by-product of the imaging process. The high number of false-positive incidental findings detected on these attenuation-correction images causes a reporting dilemma. Early detection of cancer can be beneficial, but false-positive findings and overdiagnosis can be detrimental to the patient. Attenuation-correction CT images are not of diagnostic quality, and further diagnostic tests are usually necessary for a definitive diagnosis to be reached. Given the high number of false-positive findings, the psychologic effect on the patient should be considered. This review recommends caution wh...
We describe the role of (18)F-sodium fluoride ((18)F-NaF) PET/CT bone scanning in the staging of ... more We describe the role of (18)F-sodium fluoride ((18)F-NaF) PET/CT bone scanning in the staging of breast and prostate cancer. (18)F-NaF PET was initially utilized as a bone scanning agent in the 1960s and early 1970s, however, its use was restricted by the then-available γ-cameras. The advent of hybrid PET/CT cameras in the late 1990s has shown a resurgence of interest in its use and role. After a brief introduction, this paper describes the radiopharmaceutical properties, dosimetry, pharmacokinetics, and mechanism of uptake of (18)F-NaF. The performance of (18)F-NaF PET/CT is then compared with that of conventional bone scintigraphy using current evidence from the literature. Strengths and weaknesses of (18)F-NaF PET/CT imaging are highlighted. Clinical examples of improved accuracy of diagnosis and impact on patient management are illustrated. Limitations of (18)F-NaF PET/CT imaging are outlined.
Purpose: Mammographic density has been demonstrated to predict breast cancer risk. It has been pr... more Purpose: Mammographic density has been demonstrated to predict breast cancer risk. It has been proposed that it could be used for stratifying screening pathways and recommending additional imaging. Volumetric density tools use the recorded compressed breast thickness (CBT) of the breast measured at the x-ray unit in their calculation, however the accuracy of the recorded thickness can vary. The aim of this study was to investigate whether inaccuracies in recorded CBT impact upon volumetric density classification and to examine whether the current quality control (QC) standard is sufficient for assessing mammographic density. Methods: Raw data from 52 digital screening mammograms were included in the study. For each image, the clinically recorded CBT was artificially increased and decreased to simulate measurement error. Increments of 1mm were used up to ±15% error of recorded CBT was achieved. New images were created for each 1mm step in thickness resulting in a total of 974 images which then had Volpara Density Grade (VDG) and volumetric density percentage assigned. Results: A change in VDG was recorded in 38.5% (n= 20) of mammograms when applying ±15% error to the recorded CBT and 11.5 % (n= 6) were within the QC standard prescribed error of ±5mm. Conclusion: The current QC standard of ±5mm error in recorded CBT creates the potential for error in mammographic density measurement. This may lead to inaccurate classification of mammographic density. The current QC standard for assessing mammographic density should be reconsidered.
Access to the Journal of Medical Imaging and Radiation Sciences and Radiography is a benefit of y... more Access to the Journal of Medical Imaging and Radiation Sciences and Radiography is a benefit of your SoR membership. All members can view and search through the full-text versions of the JMIRS and Radiography articles. If you wish to personalize the site in order to save your searches, view recent searches or receive e-mail alerts, please register or log in above.
Blurred images in Full Field Digital Mammography (FFDM) are a problem in the UK Breast Screening ... more Blurred images in Full Field Digital Mammography (FFDM) are a problem in the UK Breast Screening Programme. Technical recalls may be due to blurring not being seen on lower resolution monitors used for review. This study assesses the visual detection of blurring on a 2.3 megapixel (MP) monitor and a 5 MP report grade monitor and proposes an observer standard for the visual detection of blurring on a 5 MP reporting grade monitor. Twenty-eight observers assessed 120 images for blurring; 20 had no blurring present whilst 100 had blurring imposed through mathematical simulation at 0.2, 0.4, 0.6, 0.8 and 1.0 mm levels of motion. Technical recall rate for both monitors and angular size at each level of motion were calculated. Chi-squared (X(2)) tests were used to test whether significant differences in blurring detection existed between 2.3 and 5 MP monitors. The technical recall rate for 2.3 and 5 MP monitors are 20.3 % and 9.1% respectively. Angular size for 0.2 to 1 mm motion varied fr...
Comparative analysis of radiation dose and low contrast detail detectability using routine paedia... more Comparative analysis of radiation dose and low contrast detail detectability using routine paediatric chest radiography protocols Objectives: To compare low contrast detail (LCD) detectability and radiation dose for routine paediatric chest X-ray (CXR) imaging protocols among various hospitals. Methods: CDRAD 2.0 phantom and medical grade polymethyl methacrylate (PMMA) slabs were used to simulate the chest region of four different paediatric age groups. Radiographic acquisitions were undertaken on 17 X-ray machines located in eight hospitals using their existing CXR protocols. LCD detectability represented by image quality figure inverse (IQFinv) was measured physically using the CDRAD analyser software. Incident air kerma (IAK) measurements were obtained using a solid-state dosimeter. Results: The range of IQFinv, between and within the hospitals, was 1.40-4.44 and 1.52-2.18, respectively for neonates; 0.
Fo r m o r e info r m a tio n, in cl u di n g o u r p olicy a n d s u b mi s sio n p r o c e d u ... more Fo r m o r e info r m a tio n, in cl u di n g o u r p olicy a n d s u b mi s sio n p r o c e d u r e , pl e a s e c o n t a c t t h e R e p o si to ry Te a m a t: u si r@ s alfo r d. a c. u k. Research Informed Teaching Experience in Diagnostic Radiography: Perspectives of Academic Tutors and Clinical Placement Educators Introduction: This small scale qualitative research study investigated the perceptions by both academic tutors and clinical placement educators of integrating the research-informed teaching experience (RiTe) within an undergraduate radiography curriculum to support the learning and practice of image quality and dose optimisation. Method: A purposeful sampling approach was used to recruit participants and two asynchronous on-line focus groups (OFG) were used for data collection. An inductive thematic approach was taken to analyse both sets of OFG data. Results and discussion: Five academic tutors and 4 clinical placement educators participated in the research. Three overarching themes common to both sets of OFG data were identified. Findings confirmed that both OFGs felt that the Research-informed Teaching experience (RiTe) supported student learning of image quality and dose optimisation as well as the development of research skills. However, the clinical placement educators did identify that students may find it difficult to transfer and apply this knowledge into practice (theory-practice gap). Conclusion: Results from both OFGs support RiTe with regard to the teaching and practice of image quality and dose optimisation. However, greater involvement by clinical placement educators may help to overcome issues with the translation of RiTe by students into the clinical environment (theory-practice gap) and support its continued development within the curriculum. It was also identified that RiTe could be developed for qualified staff for continued professional development (CPD).
The most effective method of detecting breast cancer amongst asymptomatic women is by mammography... more The most effective method of detecting breast cancer amongst asymptomatic women is by mammography screening. Although, most countries have this preventive measure in place for women within their society; most of these programmes still struggle with women's attendance. This article discusses four health behavioural theories and models, in relation to mammography screening, including the health belief model, theory of planned behaviour, trans-theoretical model, and the theory of care seeking behaviour that may explain the factors affecting women's participation in mammography screening. In summary, analysis of these theories indicates that the theory of care seeking behaviour has value for exploring the factors affecting women's participation in mammography screening. This is because of its sensitivity to socioeconomic differences that exists amongst women in the society, and that it has a broader construct (such as habit and external factors) compared to the other health behavioural theories.
Ti t l e O p e r a t o r e y e d o s e s d u ri n g c o m p u t e d t o m o g r a p h y fluo r o ... more Ti t l e O p e r a t o r e y e d o s e s d u ri n g c o m p u t e d t o m o g r a p h y fluo r o s c o pic lu n g bio p sy
Detection of breast cancer is reliant on optimal breast positioning and the production of quality... more Detection of breast cancer is reliant on optimal breast positioning and the production of quality images. Two projections, the mediolateral oblique and craniocaudal (CC), are routinely performed. Determination of successful positioning and inclusion of all breast tissue is achieved through meeting stated image quality criteria. For the CC view, current image quality criteria are inconsistent. Absence of reliable anatomical markers, other than the nipple, further contribute to difficulties in assessing the quality of CC views. The aim of this paper was to explore published international quality standards to identify and find the origin of any CC positioning criteria which might provide for quantitative assessment. The pectoralis major (pectoral) muscle was identified as a key posterior anatomical structure to establish optimum breast tissue inclusion on mammographic projections. It forms the first two of the three main CC metrics that are frequently reported (1) visualization of the ...
Journal of medical radiation sciences, Jan 26, 2017
Within the professions of radiation therapy and medical imaging, clinician led research activity ... more Within the professions of radiation therapy and medical imaging, clinician led research activity is becoming more prevalent. However, more is needed. A key component of continuing to develop professional groups who are both research active and producing high quality clinical research, is research mentoring. The authors of this paper share a common interest in enhancing research capacity through research mentoring within the health workforce, and came together to run a workshop on this issue at the 11th Annual Scientific Meeting of Medical Imaging and Radiation Therapy (ASMMIRT 2016) conference in Brisbane. Theory, clinical insights and issues regarding research mentoring were raised in the workshop as were the benefits of having dedicated research positions embedded within the health workforce to help provide support and build capacity. Key elements from this workshop are shared within this article, with the objective to encourage clinicians and clinical researchers to invest the ti...
Since the introduction of full field digital mammography (FFDM) a large number of UK breast cance... more Since the introduction of full field digital mammography (FFDM) a large number of UK breast cancer screening centers have reported blurred images, which can be caused by movement at the compression paddle during image acquisition. To propose and investigate the use of position feedback from the breast side of the compression paddle to reduce the settling time of breast side motion. Movement at the breast side of the paddle was measured using two calibrated linear potentiometers. A mathematical model for the compression paddle, machine drive, and breast was developed using the paddle movement data. Simulation software was used to optimize the position feedback controller parameters for different machine drive time constants and simulate the potential performance of the proposed system. The results obtained are based on simulation alone and indicate that closed-loop control of breast side paddle position dramatically reduced the settling time from over 90 s to less than 4 s. The effec...
Motion blur is a known phenomenon in full-field digital mammography, but the impact on lesion det... more Motion blur is a known phenomenon in full-field digital mammography, but the impact on lesion detection is unknown. This is the first study to investigate detection performance with varying magnitudes of simulated motion blur. Seven observers (15±5 years' reporting experience) evaluated 248 cases (62 containing malignant masses, 62 containing malignant microcalcifications and 124 normal cases) for three conditions: no blurring (0 mm) and two magnitudes of simulated blurring (0.7 mm and 1.5 mm). Abnormal cases were biopsy proven. Mathematical simulation was used to provide a pixel shift in order to simulate motion blur. A free-response observer study was conducted to compare lesion detection performance for the three conditions. The equally weighted jackknife alternative free-response receiver operating characteristic (wJAFROC) was used as the figure of merit. Test alpha was set at 0.05 to control probability of Type I error. wJAFROC analysis found a statistically significant dif...
Compression is used in mammography to reduce breast thickness, which is claimed to improve image ... more Compression is used in mammography to reduce breast thickness, which is claimed to improve image quality and reduce radiation dose. In the XXX Breast Cancer Screening Program (XBCSP), the recommended range of compression force for full field digital mammography is 11-18 kg (108-177 Newton [N]). This is the first study to investigate the compression force used in the program. The study included information from 17,951 randomly selected women screened with FFDM at 14 breast centres in the XBCSP, January-March 2014. We investigated the applied compression force on left breast in craniocaudal (CC) and mediolateral oblique (MLO) view for breast centres, mammography machines within the breast centres and for the radiographers. The mean compression force for all mammograms in the study was 116N and ranged from 91 to 147N between the breast centres. The variation in compression force was wider between the breast centres than between mammography machines (range 137-155N) and radiographers (9...
Incidental findings are common in medical imaging. There is a particularly high prevalence of inc... more Incidental findings are common in medical imaging. There is a particularly high prevalence of incidental findings within the thorax, the most frequent being pulmonary nodules. Although pulmonary nodules have the potential to be malignant, most are benign, resulting in a high number of false-positive findings. Low-resolution CT images produced for attenuation correction of SPECT images are essentially a by-product of the imaging process. The high number of false-positive incidental findings detected on these attenuation-correction images causes a reporting dilemma. Early detection of cancer can be beneficial, but false-positive findings and overdiagnosis can be detrimental to the patient. Attenuation-correction CT images are not of diagnostic quality, and further diagnostic tests are usually necessary for a definitive diagnosis to be reached. Given the high number of false-positive findings, the psychologic effect on the patient should be considered. This review recommends caution wh...
We describe the role of (18)F-sodium fluoride ((18)F-NaF) PET/CT bone scanning in the staging of ... more We describe the role of (18)F-sodium fluoride ((18)F-NaF) PET/CT bone scanning in the staging of breast and prostate cancer. (18)F-NaF PET was initially utilized as a bone scanning agent in the 1960s and early 1970s, however, its use was restricted by the then-available γ-cameras. The advent of hybrid PET/CT cameras in the late 1990s has shown a resurgence of interest in its use and role. After a brief introduction, this paper describes the radiopharmaceutical properties, dosimetry, pharmacokinetics, and mechanism of uptake of (18)F-NaF. The performance of (18)F-NaF PET/CT is then compared with that of conventional bone scintigraphy using current evidence from the literature. Strengths and weaknesses of (18)F-NaF PET/CT imaging are highlighted. Clinical examples of improved accuracy of diagnosis and impact on patient management are illustrated. Limitations of (18)F-NaF PET/CT imaging are outlined.
Purpose: Mammographic density has been demonstrated to predict breast cancer risk. It has been pr... more Purpose: Mammographic density has been demonstrated to predict breast cancer risk. It has been proposed that it could be used for stratifying screening pathways and recommending additional imaging. Volumetric density tools use the recorded compressed breast thickness (CBT) of the breast measured at the x-ray unit in their calculation, however the accuracy of the recorded thickness can vary. The aim of this study was to investigate whether inaccuracies in recorded CBT impact upon volumetric density classification and to examine whether the current quality control (QC) standard is sufficient for assessing mammographic density. Methods: Raw data from 52 digital screening mammograms were included in the study. For each image, the clinically recorded CBT was artificially increased and decreased to simulate measurement error. Increments of 1mm were used up to ±15% error of recorded CBT was achieved. New images were created for each 1mm step in thickness resulting in a total of 974 images which then had Volpara Density Grade (VDG) and volumetric density percentage assigned. Results: A change in VDG was recorded in 38.5% (n= 20) of mammograms when applying ±15% error to the recorded CBT and 11.5 % (n= 6) were within the QC standard prescribed error of ±5mm. Conclusion: The current QC standard of ±5mm error in recorded CBT creates the potential for error in mammographic density measurement. This may lead to inaccurate classification of mammographic density. The current QC standard for assessing mammographic density should be reconsidered.
Access to the Journal of Medical Imaging and Radiation Sciences and Radiography is a benefit of y... more Access to the Journal of Medical Imaging and Radiation Sciences and Radiography is a benefit of your SoR membership. All members can view and search through the full-text versions of the JMIRS and Radiography articles. If you wish to personalize the site in order to save your searches, view recent searches or receive e-mail alerts, please register or log in above.
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Papers by Peter Hogg