Cynthia L Eccles DPHIL | University of Oxford (original) (raw)

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Papers by Cynthia L Eccles DPHIL

Research paper thumbnail of A novel use for routine CBCT imaging during radiotherapy to detect COVID-19

Radiography, 2022

Introduction: Thoracic CT is a useful tool in the early diagnosis of patients with COVID-19. Typi... more Introduction: Thoracic CT is a useful tool in the early diagnosis of patients with COVID-19. Typical appearances include patchy ground glass shadowing. Thoracic radiotherapy uses daily cone beam CT imaging (CBCT) to check for changes in patient positioning and anatomy prior to treatment through a qualitative assessment of lung appearance by radiographers. Observation of changes related to COVID-19 infection during this process may facilitate earlier testing improving patient management and staff protection. Methods: A tool was developed to create overview reports for all CBCTs for each patient throughout their treatment. Reports contain coronal maximum intensity projection (MIP's) of all CBCTs and plots of lung density over time. A single therapeutic radiographer undertook a blinded off-line audit that reviewed 150 patient datasets for tool optimisation in which medical notes were compared to image findings. This cohort included 75 patients treated during the pandemic and 75 patients treated between 2014 and 2017. The process was repeated retrospectively on a subset of the 285 thoracic radiotherapy patients treated between JanuaryeJune 2020 to assess the efficiency of the tool and process. Results: Three patients in the n ¼ 150 optimisation cohort had confirmed COVID-19 infections during their radiotherapy. Two of these were detected by the reported image assessment process. The third case was not detected on CBCT due to minimal density changes in the visible part of the lungs. Within the retrospective cohort four patients had confirmed COVID-19 based on RT-PCR tests, three of which were retrospectively detected by the reported process. Conclusion: The preliminary results indicate that the presence of COVID-19 can be detected on CBCT by therapeutic radiographers. Implications for practice: This process has now been extended to clinical service with daily assessments of all thoracic CBCTs. Changes noted are referred for oncologist review.

Research paper thumbnail of Effect of PI3K-Inhibition on Normal Lung Tissue Following Irradiation in a Murine Model

International Journal of Radiation Oncology*Biology*Physics, 2015

Research paper thumbnail of PH-0406: An IPEM international survey of MRI use for external beam RT treatment planning

Radiotherapy and Oncology, 2020

Research paper thumbnail of Streamlining the image-guided radiotherapy process for proton beam therapy

The British Journal of Radiology, 2021

Objectives: This work evaluated the on-treatment imaging workflow in the UK’s first proton beam t... more Objectives: This work evaluated the on-treatment imaging workflow in the UK’s first proton beam therapy (PBT) centre, with a view to reducing times and unnecessary imaging doses to patients. Methods: Imaging dose and timing data from the first 20 patients (70% paediatrics, 30% TYA/adult) treated with PBT using the initial image-guided PBT (IGPBT) workflow of a 2-dimensional kilo-voltage (2DkV), followed by cone-beam computed-tomography (CBCT) and repeat 2DkV was included. Pearson correlations and Bland-Altman analysis were used to describe correlations between 2DkV and CBCT images to determine if any images were superfluous. Results: 229 treatment sessions were evaluated. Patient repositioning following the initial 2DkV (i2DkV) was required on 19 (8.3%) fractions. This three-step process resulted in an additional mean imaging dose of 3.4 mGy per patient, and 5.1 minutes on the treatment bed for the patient, over a whole course of PBT, compared to a two-step workflow (removing the i2...

Research paper thumbnail of Intravenous Contrast Enhanced Cone beam CT (IVCBCT) of Intrahepatic Tumours and Vessels

Research paper thumbnail of EP-1613: Comparison of prostate delineation on multi-modality imaging for MR-guided radiotherapy

Radiotherapy and Oncology

Research paper thumbnail of Early Experience of Magnetic Resonance Sequence Evaluation Using an MR-Linac System

International Journal of Radiation Oncology*Biology*Physics

Research paper thumbnail of PV-0461: Integrating diagnostic MRI in radical bladder cancer radiotherapy: Challenges in image registration

Radiotherapy and Oncology

Research paper thumbnail of In response to Westbrook – Opening the debate on MRI practitioner education

Research paper thumbnail of PO-0946: Methods for assessing atlas-based contouring in head and neck cancer

Radiotherapy and Oncology

Purpose/Objective: At the Beatson Cancer Centre, we have developed a novel treatment delivery tec... more Purpose/Objective: At the Beatson Cancer Centre, we have developed a novel treatment delivery technique for our SABR lung patients. This involves an 'arms down' patient setup , utilising thermoplastic thorax immobilisation, 4DCT-based planning, and online CBCT verification prior to each fraction and VMAT delivered IMRT to assess the effectiveness of patient setup using our immobilisation, and quantify associated patient intrafraction motion, on-treatment verification using CBCT pre and post treatment delivery was carried out. Here, we report the results of our first 28 SABR patients. Materials and Methods: Patients are placed in a supine position with their arms by their sides, on a BDS board (Sinmed, Iowa, USA). Head and neck support is individualised to ensure comfort, support and to minimise gaps at the base of the neck. Thoracic immobilisation is provided by a thermoplastic (Klarity, Ohio, USA) mould with 4 point fixation, which supports the patient from the inferior edge of the lower lip to the mid thorax or lower where possible. Each patient receiving SABR with VMAT (55 Gy/5#) undergoes a CBCT prior to treatment and then further CBCT on completion of each fraction. A region of interest was used to perform an automatic bony match between the pre and post treatment CBCTs. The patient intrafraction motion is represented by the difference between pre and post treatment bony matches. differences were measured for each CBCT. Results: Analysis was based on the first 28 patients, which produced 138 CBCT image sets. For each direction, the frequency distribution of setup shifts and a confidence interval was calculated.

Research paper thumbnail of MRI and CBCT for lymph node identification and registration in patients with NSCLC undergoing radical radiotherapy

Radiotherapy and Oncology

Research paper thumbnail of The impact of gadolinium‐based MR contrast on radiotherapy planning for oropharyngeal treatment on the MR Linac

Research paper thumbnail of IPEM topical report: guidance on the use of MRI for external beam radiotherapy treatment planning

Physics in Medicine & Biology

Research paper thumbnail of Comparison of radiographer interobserver image registration variability using cone beam CT and MR for cervix radiotherapy

The British Journal of Radiology

Objectives: The aim of this study was to assess the consistency of therapy radiographers performi... more Objectives: The aim of this study was to assess the consistency of therapy radiographers performing image registration using cone beam computed tomography (CBCT)-CT, magnetic resonance (MR)-CT, and MR-MR image guidance for cervix cancer radiotherapy and to assess that MR-based image guidance is not inferior to CBCT standard practice. Methods: 10 patients receiving cervix radiation therapy underwent daily CBCT guidance and magnetic resonance (MR) imaging weekly during treatment. Offline registration of each MR image, and corresponding CBCT, to planning CT was performed by five radiographers. MR images were also registered to the earliest MR interobserver variation was assessed using modified Bland–Altman analysis with clinically acceptable 95% limits of agreement (LoA) defined as ±5.0 mm. Results: 30 CBCT-CT, 30 MR-CT and 20 MR–MR registrations were performed by each observer. Registration variations between CBCT-CT and MR-CT were minor and both strategies resulted in 95% LoA over th...

Research paper thumbnail of Magnetic resonance‐guided radiation therapy: A review

Journal of Medical Imaging and Radiation Oncology

Research paper thumbnail of IPEM Topical Report: A 2018 IPEM survey of MRI use for external beam radiotherapy treatment planning in the UK

Physics in Medicine and Biology

Research paper thumbnail of Keeping Up with the Hybrid Magnetic Resonance Linear Accelerators: How Do Radiation Therapists Stay Current in the Era of Hybrid Technologies?

Journal of Medical Imaging and Radiation Sciences

The benefits of integrating magnetic resonance imaging (MRI) into radiotherapy planning have long... more The benefits of integrating magnetic resonance imaging (MRI) into radiotherapy planning have long been extolled, first appearing in the literature as early as 1986. Most often described as a tool to be used when registered to a planning computed tomography to improve target and organ at risk delineation, the use of MRI for on-board image guidance and as a sole imaging modality throughout the entire radiotherapy pathway is quickly becoming a reality for appropriately selected patient populations in academic centres throughout the world. With the commercialization of these integrated magnetic resonance-radiotherapy delivery systems, an MRI-only workflow will prove beneficial, with MRI being used for treatment planning, localization, and on-treatment plan adaptation. Despite these technological advancements, recent surveys indicate uptake of MRI in radiotherapy as a routine practice has proven challenging. Reasons cited for this slow uptake were primarily related to health economics and/or accessibility. Furthermore, these surveys, like much of the academic literature, shy away from focusing on safe, sustainable staffing models enabled by comprehensive and appropriate education and training. In stark contrast to conebeam computed tomography guided therapy, magnetic resonance-radiotherapy systems are currently being operated by teams of physicians, radiographers, and physicists because of the diverse and complex tasks required to deliver treatment. The pace of innovation in RT remains high and unfortunately the window of opportunity to implement appropriate education continues to narrow. It is vital that we establish a framework to future-proof our profession. In the era of magnetic resonanceguided radiotherapy, we have yet to address the question of how to devise a consensus on the requisite knowledge, skills, and competence for radiation therapists and therapy radiographers using and/ or operating MRI that provides guidance, without becoming prohibitively costly or time consuming.

Research paper thumbnail of Comparison of prostate delineation on multimodality imaging for MR-guided radiotherapy

The British Journal of Radiology

Research paper thumbnail of P-182 * Clinical outcomes of a phase II study of nelfinavir, a hypoxia-modifying agent, in combination with chemoradiotherapy in locally-advanced pancreatic cancer - functional imaging is prognostic and provides proof of mechanism

Research paper thumbnail of Intravenous contrast-enhanced cone beam computed tomography (IVCBCT) of intrahepatic tumors and vessels

Advances in Radiation Oncology, 2016

Liver tumors are challenging to visualize on cone beam computed tomography (CBCT) without intrave... more Liver tumors are challenging to visualize on cone beam computed tomography (CBCT) without intravenous (IV) contrast. Image guidance for liver cancer stereotactic body ablative radiation therapy (SABR) could be improved with the direct visualization of hepatic tumors and vasculature. This study investigated the feasibility of the use of IV contrast-enhanced CBCT (IV-CBCT) as a means to improve liver target visualization. Methods and Materials: Patients on a liver SABR protocol underwent IV-CBCT before 1 or more treatment fractions in addition to a noncontrast CBCT. Image acquisition was initiated 0 to 30 seconds following injection and acquired over 60 to 120 seconds. "Stop and go" exhale breath-hold CBCT scans were used whenever feasible. Changes in mean CT number in regions of interest within visible vasculature, tumor, and adjacent liver were quantified between CBCT and IV-CBCT. Results: Twelve pairs of contrast and noncontrast CBCTs were obtained in 7 patients. Intravenous-CBCT improved hepatic tumor visibility in breath-hold scans only for 3 patients (2 metastases, 1 hepatocellular carcinoma). Visible tumors ranged in volume from 124 to 564 mL. Small tumors in free-breathing patients did not show enhancement on IVCBT. Conclusions: Intravenous-CBCT may enhance the visibility of hepatic vessels and tumor in CBCT scans obtained during breath hold. Optimization of IV contrast timing and reduction of artifacts to improve tumor visualization warrant further investigation.

Research paper thumbnail of A novel use for routine CBCT imaging during radiotherapy to detect COVID-19

Radiography, 2022

Introduction: Thoracic CT is a useful tool in the early diagnosis of patients with COVID-19. Typi... more Introduction: Thoracic CT is a useful tool in the early diagnosis of patients with COVID-19. Typical appearances include patchy ground glass shadowing. Thoracic radiotherapy uses daily cone beam CT imaging (CBCT) to check for changes in patient positioning and anatomy prior to treatment through a qualitative assessment of lung appearance by radiographers. Observation of changes related to COVID-19 infection during this process may facilitate earlier testing improving patient management and staff protection. Methods: A tool was developed to create overview reports for all CBCTs for each patient throughout their treatment. Reports contain coronal maximum intensity projection (MIP's) of all CBCTs and plots of lung density over time. A single therapeutic radiographer undertook a blinded off-line audit that reviewed 150 patient datasets for tool optimisation in which medical notes were compared to image findings. This cohort included 75 patients treated during the pandemic and 75 patients treated between 2014 and 2017. The process was repeated retrospectively on a subset of the 285 thoracic radiotherapy patients treated between JanuaryeJune 2020 to assess the efficiency of the tool and process. Results: Three patients in the n ¼ 150 optimisation cohort had confirmed COVID-19 infections during their radiotherapy. Two of these were detected by the reported image assessment process. The third case was not detected on CBCT due to minimal density changes in the visible part of the lungs. Within the retrospective cohort four patients had confirmed COVID-19 based on RT-PCR tests, three of which were retrospectively detected by the reported process. Conclusion: The preliminary results indicate that the presence of COVID-19 can be detected on CBCT by therapeutic radiographers. Implications for practice: This process has now been extended to clinical service with daily assessments of all thoracic CBCTs. Changes noted are referred for oncologist review.

Research paper thumbnail of Effect of PI3K-Inhibition on Normal Lung Tissue Following Irradiation in a Murine Model

International Journal of Radiation Oncology*Biology*Physics, 2015

Research paper thumbnail of PH-0406: An IPEM international survey of MRI use for external beam RT treatment planning

Radiotherapy and Oncology, 2020

Research paper thumbnail of Streamlining the image-guided radiotherapy process for proton beam therapy

The British Journal of Radiology, 2021

Objectives: This work evaluated the on-treatment imaging workflow in the UK’s first proton beam t... more Objectives: This work evaluated the on-treatment imaging workflow in the UK’s first proton beam therapy (PBT) centre, with a view to reducing times and unnecessary imaging doses to patients. Methods: Imaging dose and timing data from the first 20 patients (70% paediatrics, 30% TYA/adult) treated with PBT using the initial image-guided PBT (IGPBT) workflow of a 2-dimensional kilo-voltage (2DkV), followed by cone-beam computed-tomography (CBCT) and repeat 2DkV was included. Pearson correlations and Bland-Altman analysis were used to describe correlations between 2DkV and CBCT images to determine if any images were superfluous. Results: 229 treatment sessions were evaluated. Patient repositioning following the initial 2DkV (i2DkV) was required on 19 (8.3%) fractions. This three-step process resulted in an additional mean imaging dose of 3.4 mGy per patient, and 5.1 minutes on the treatment bed for the patient, over a whole course of PBT, compared to a two-step workflow (removing the i2...

Research paper thumbnail of Intravenous Contrast Enhanced Cone beam CT (IVCBCT) of Intrahepatic Tumours and Vessels

Research paper thumbnail of EP-1613: Comparison of prostate delineation on multi-modality imaging for MR-guided radiotherapy

Radiotherapy and Oncology

Research paper thumbnail of Early Experience of Magnetic Resonance Sequence Evaluation Using an MR-Linac System

International Journal of Radiation Oncology*Biology*Physics

Research paper thumbnail of PV-0461: Integrating diagnostic MRI in radical bladder cancer radiotherapy: Challenges in image registration

Radiotherapy and Oncology

Research paper thumbnail of In response to Westbrook – Opening the debate on MRI practitioner education

Research paper thumbnail of PO-0946: Methods for assessing atlas-based contouring in head and neck cancer

Radiotherapy and Oncology

Purpose/Objective: At the Beatson Cancer Centre, we have developed a novel treatment delivery tec... more Purpose/Objective: At the Beatson Cancer Centre, we have developed a novel treatment delivery technique for our SABR lung patients. This involves an 'arms down' patient setup , utilising thermoplastic thorax immobilisation, 4DCT-based planning, and online CBCT verification prior to each fraction and VMAT delivered IMRT to assess the effectiveness of patient setup using our immobilisation, and quantify associated patient intrafraction motion, on-treatment verification using CBCT pre and post treatment delivery was carried out. Here, we report the results of our first 28 SABR patients. Materials and Methods: Patients are placed in a supine position with their arms by their sides, on a BDS board (Sinmed, Iowa, USA). Head and neck support is individualised to ensure comfort, support and to minimise gaps at the base of the neck. Thoracic immobilisation is provided by a thermoplastic (Klarity, Ohio, USA) mould with 4 point fixation, which supports the patient from the inferior edge of the lower lip to the mid thorax or lower where possible. Each patient receiving SABR with VMAT (55 Gy/5#) undergoes a CBCT prior to treatment and then further CBCT on completion of each fraction. A region of interest was used to perform an automatic bony match between the pre and post treatment CBCTs. The patient intrafraction motion is represented by the difference between pre and post treatment bony matches. differences were measured for each CBCT. Results: Analysis was based on the first 28 patients, which produced 138 CBCT image sets. For each direction, the frequency distribution of setup shifts and a confidence interval was calculated.

Research paper thumbnail of MRI and CBCT for lymph node identification and registration in patients with NSCLC undergoing radical radiotherapy

Radiotherapy and Oncology

Research paper thumbnail of The impact of gadolinium‐based MR contrast on radiotherapy planning for oropharyngeal treatment on the MR Linac

Research paper thumbnail of IPEM topical report: guidance on the use of MRI for external beam radiotherapy treatment planning

Physics in Medicine & Biology

Research paper thumbnail of Comparison of radiographer interobserver image registration variability using cone beam CT and MR for cervix radiotherapy

The British Journal of Radiology

Objectives: The aim of this study was to assess the consistency of therapy radiographers performi... more Objectives: The aim of this study was to assess the consistency of therapy radiographers performing image registration using cone beam computed tomography (CBCT)-CT, magnetic resonance (MR)-CT, and MR-MR image guidance for cervix cancer radiotherapy and to assess that MR-based image guidance is not inferior to CBCT standard practice. Methods: 10 patients receiving cervix radiation therapy underwent daily CBCT guidance and magnetic resonance (MR) imaging weekly during treatment. Offline registration of each MR image, and corresponding CBCT, to planning CT was performed by five radiographers. MR images were also registered to the earliest MR interobserver variation was assessed using modified Bland–Altman analysis with clinically acceptable 95% limits of agreement (LoA) defined as ±5.0 mm. Results: 30 CBCT-CT, 30 MR-CT and 20 MR–MR registrations were performed by each observer. Registration variations between CBCT-CT and MR-CT were minor and both strategies resulted in 95% LoA over th...

Research paper thumbnail of Magnetic resonance‐guided radiation therapy: A review

Journal of Medical Imaging and Radiation Oncology

Research paper thumbnail of IPEM Topical Report: A 2018 IPEM survey of MRI use for external beam radiotherapy treatment planning in the UK

Physics in Medicine and Biology

Research paper thumbnail of Keeping Up with the Hybrid Magnetic Resonance Linear Accelerators: How Do Radiation Therapists Stay Current in the Era of Hybrid Technologies?

Journal of Medical Imaging and Radiation Sciences

The benefits of integrating magnetic resonance imaging (MRI) into radiotherapy planning have long... more The benefits of integrating magnetic resonance imaging (MRI) into radiotherapy planning have long been extolled, first appearing in the literature as early as 1986. Most often described as a tool to be used when registered to a planning computed tomography to improve target and organ at risk delineation, the use of MRI for on-board image guidance and as a sole imaging modality throughout the entire radiotherapy pathway is quickly becoming a reality for appropriately selected patient populations in academic centres throughout the world. With the commercialization of these integrated magnetic resonance-radiotherapy delivery systems, an MRI-only workflow will prove beneficial, with MRI being used for treatment planning, localization, and on-treatment plan adaptation. Despite these technological advancements, recent surveys indicate uptake of MRI in radiotherapy as a routine practice has proven challenging. Reasons cited for this slow uptake were primarily related to health economics and/or accessibility. Furthermore, these surveys, like much of the academic literature, shy away from focusing on safe, sustainable staffing models enabled by comprehensive and appropriate education and training. In stark contrast to conebeam computed tomography guided therapy, magnetic resonance-radiotherapy systems are currently being operated by teams of physicians, radiographers, and physicists because of the diverse and complex tasks required to deliver treatment. The pace of innovation in RT remains high and unfortunately the window of opportunity to implement appropriate education continues to narrow. It is vital that we establish a framework to future-proof our profession. In the era of magnetic resonanceguided radiotherapy, we have yet to address the question of how to devise a consensus on the requisite knowledge, skills, and competence for radiation therapists and therapy radiographers using and/ or operating MRI that provides guidance, without becoming prohibitively costly or time consuming.

Research paper thumbnail of Comparison of prostate delineation on multimodality imaging for MR-guided radiotherapy

The British Journal of Radiology

Research paper thumbnail of P-182 * Clinical outcomes of a phase II study of nelfinavir, a hypoxia-modifying agent, in combination with chemoradiotherapy in locally-advanced pancreatic cancer - functional imaging is prognostic and provides proof of mechanism

Research paper thumbnail of Intravenous contrast-enhanced cone beam computed tomography (IVCBCT) of intrahepatic tumors and vessels

Advances in Radiation Oncology, 2016

Liver tumors are challenging to visualize on cone beam computed tomography (CBCT) without intrave... more Liver tumors are challenging to visualize on cone beam computed tomography (CBCT) without intravenous (IV) contrast. Image guidance for liver cancer stereotactic body ablative radiation therapy (SABR) could be improved with the direct visualization of hepatic tumors and vasculature. This study investigated the feasibility of the use of IV contrast-enhanced CBCT (IV-CBCT) as a means to improve liver target visualization. Methods and Materials: Patients on a liver SABR protocol underwent IV-CBCT before 1 or more treatment fractions in addition to a noncontrast CBCT. Image acquisition was initiated 0 to 30 seconds following injection and acquired over 60 to 120 seconds. "Stop and go" exhale breath-hold CBCT scans were used whenever feasible. Changes in mean CT number in regions of interest within visible vasculature, tumor, and adjacent liver were quantified between CBCT and IV-CBCT. Results: Twelve pairs of contrast and noncontrast CBCTs were obtained in 7 patients. Intravenous-CBCT improved hepatic tumor visibility in breath-hold scans only for 3 patients (2 metastases, 1 hepatocellular carcinoma). Visible tumors ranged in volume from 124 to 564 mL. Small tumors in free-breathing patients did not show enhancement on IVCBT. Conclusions: Intravenous-CBCT may enhance the visibility of hepatic vessels and tumor in CBCT scans obtained during breath hold. Optimization of IV contrast timing and reduction of artifacts to improve tumor visualization warrant further investigation.