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  • ItemOpen AccessPublished version Peer-reviewed
    UK quantitative WB-DWI technical workgroup: consensus meeting recommendations on optimisation, quality control, processing and analysis of quantitative whole-body diffusion-weighted imaging for cancer.
    (British Institute of Radiology, 2018-01) Barnes, Anna; Alonzi, Roberto; Blackledge, Matthew; Charles-Edwards, Geoff; Collins, David J; Cook, Gary; Coutts, Glynn; Goh, Vicky; Graves, Martin; Kelly, Charles; Koh, Dow-Mu; McCallum, Hazel; Miquel, Marc E; O'Connor, James; Padhani, Anwar; Pearson, Rachel; Priest, Andrew; Rockall, Andrea; Stirling, James; Taylor, Stuart; Tunariu, Nina; van der Meulen, Jan; Walls, Darren; Winfield, Jessica; Punwani, Shonit; Graves, Martin [0000-0003-4327-3052]
    OBJECTIVE: Application of whole body diffusion-weighted MRI (WB-DWI) for oncology are rapidly increasing within both research and routine clinical domains. However, WB-DWI as a quantitative imaging biomarker (QIB) has significantly slower adoption. To date, challenges relating to accuracy and reproducibility, essential criteria for a good QIB, have limited widespread clinical translation. In recognition, a UK workgroup was established in 2016 to provide technical consensus guidelines (to maximise accuracy and reproducibility of WB-MRI QIBs) and accelerate the clinical translation of quantitative WB-DWI applications for oncology. METHODS: A panel of experts convened from cancer centres around the UK with subspecialty expertise in quantitative imaging and/or the use of WB-MRI with DWI. A formal consensus method was used to obtain consensus agreement regarding best practice. Questions were asked about the appropriateness or otherwise on scanner hardware and software, sequence optimisation, acquisition protocols, reporting, and ongoing quality control programs to monitor precision and accuracy and agreement on quality control. RESULTS: The consensus panel was able to reach consensus on 73% (255/351) items and based on consensus areas made recommendations to maximise accuracy and reproducibly of quantitative WB-DWI studies performed at 1.5T. The panel were unable to reach consensus on the majority of items related to quantitative WB-DWI performed at 3T. CONCLUSION: This UK Quantitative WB-DWI Technical Workgroup consensus provides guidance on maximising accuracy and reproducibly of quantitative WB-DWI for oncology. The consensus guidance can be used by researchers and clinicians to harmonise WB-DWI protocols which will accelerate clinical translation of WB-DWI-derived QIBs.
  • ItemOpen AccessAccepted version Peer-reviewed
    Multicentre evaluation of Magnetic Resonance Imaging sup-ported transperineal prostate biopsy in biopsy-naïve men with suspicion of prostate cancer.
    (Wiley-Blackwell, 2018-06-11) Barrett, T; Barrett, Tristan [0000-0002-1180-1474]
    Objectives: To analyse the detection rates of primary MRI-fusion transperineal prostate biopsy using combined targeted and systematic core distribution in three tertiary referral centres. Patients and Methods: Multicentre, prospective outcome study of 807 consecutive biopsy-naïve patients having undergone MRI-guided transperineal prostate biopsy as the first diagnostic intervention between 10/2012 and 05/2016. MRI was reported following PI-RADS criteria. 236 patients had 18-24 systematic transperineal biopsies only, and 571 patients underwent additional targeted biopsies either by MRI-fusion or cognitive targeting if PI-RADS ≥3 lesions were present. Detection rates for any and Gleason score (GS) 7-10 cancer in targeted and overall biopsy. Predictive values were calculated for different PI-RADS and PSA density (PSA-D) groups. Results: Cancer was detected in 68% and GS 7-10 in 49% of patients. Negative predictive value of 236 PI-RADS 1-2 MRI in combination with PSA-D ≤0.1 ng/ml/cm3 for GS7-10 was 0.91 (±0.07, 8% of study population). In 418 patients with PI-RADS 4-5 lesions using targeted plus systematic biopsies, the cancer detection rate of GS 7-10 was significantly higher at 71% versus 59% and 61% with either approach alone (p=0.000). For 153 PI-RADS 3 lesions, the detection rate was 31% with no significant difference to systematic biopsies with 27% (p>0.05). Limitations include variability of mpMRI reading and Gleason grading. Conclusion: MRI-based transperineal biopsy performed at high volume, tertiary care centres with a significant experience of prostate mpMRI and image-guided targeted biopsies yielded high detection rates of GS 7-10 cancer. Prostate biopsies may not be needed for men with low PSA-D and a non-suspicious MRI. In patients with high probability lesions, combined targeted and systematic biopsies are recommended.
  • ItemOpen AccessAccepted version Peer-reviewed
    Can unenhanced MRI of the breast replace contrast-enhanced MRI in assessing response to neoadjuvant chemotherapy?
    (SAGE Publications, 2019-01) Cavallo Marincola, Beatrice; Telesca, Marianna; Zaccagna, Fulvio; Riemer, Frank; Anzidei, Michele; Catalano, Carlo; Pediconi, Federica; Zaccagna, Fulvio [0000-0001-6838-9532]; Riemer, Frank [0000-0002-3805-5221]
    BACKGROUND: The goals of neoadjuvant chemotherapy (NAC) are to reduce tumor volume and to offer a prognostic indicator in assessing treatment response. Contrast-enhanced magnetic resonance imaging (CE-MRI) is an established method for evaluating response to NAC in patients with breast cancer. PURPOSE: To validate the role of unenhanced MRI (ue-MRI) compared to CE-MRI for assessing response to NAC in women with breast cancer. MATERIAL AND METHODS: Seventy-one patients with ongoing NAC for breast cancer underwent MRI before, during, and at the end of NAC. Ue-MRI was performed with T2-weighted sequences with iterative decomposition of water and fat and diffusion-weighted sequences. CE-MRI was performed using three-dimensional T1-weighted sequences before and after administration of gadobenate dimeglumine. Two blinded observers rated ue-MRI and CE-MRI for the evaluation of tumor response. Statistical analysis was performed to compare lesion size and ADC values changes during therapy, as well as inter-observer agreement. RESULTS: There were no statistically significant differences between ue-MRI and CE-MRI sequences for evaluation of lesion size at baseline and after every cycle of treatment ( P > 0.05). The mean tumor ADC values at baseline and across the cycles of NAC were significantly different for the responder group. CONCLUSION: Ue-MRI can achieve similar results to CE-MRI for the assessment of tumor response to NAC. ADC values can differentiate responders from non-responders.
  • ItemOpen AccessAccepted version Peer-reviewed
    Imaging techniques in ALS.
    (Pisa University Press, 2017-12-01) Zaccagna, Fulvio; Lucignani, Giulia; Raz, Eytan; Colonnese, Claudio; Zaccagna, Fulvio [0000-0001-6838-9532]
    Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease characterized by degeneration of both upper and lower motor neuron located in the spinal cord and brainstem. Diagnosis of ALS is predominantly clinical, nevertheless, electromyography and Magnetic Resonance Imaging (MRI) may provide support. Several advanced MRI techniques have been proven useful for ALS diagnosis and, indeed, the combination of different MRI techniques demonstrated an improvement in sensitivity and specificity as far as 90%. This review focus on the imaging techniques currently used in the diagnosis and management of ALS with brief considerations on future applications.
  • ItemOpen AccessAccepted version Peer-reviewed
    Resting-state functional connectivity MRI analysis in Human Immunodeficiency Virus and Hepatitis C Virus co-infected subjects. A pilot study.
    (Elsevier BV, 2018-05) Corgiolu, Simone; Barberini, Luigi; Suri, Jasjit S; Mandas, Antonella; Costaggiu, Diego; Piano, Paola; Zaccagna, Fulvio; Lucatelli, Pierleone; Balestrieri, Antonella; Saba, Luca; Zaccagna, Fulvio [0000-0001-6838-9532]
    BACKGROUND AND PURPOSE: Hepatitis C virus (HCV) co-infection's role on cognitive impairment of human immunodeficiency virus (HIV) positive patients is still debated and functional neuroimaging evaluation on this matter is lacking. To provide further insight about HCV's neuro-effects on HIV associated neurocognitive disorder (HAND), we performed a pilot resting state (RS) functional connectivity magnetic resonance imaging (fcMRI) study to find eventual functional connectivity alteration that could reflect HCV related cognitive performance degradation. METHODS: Eighteen patients (8 HIV, 10 HIV + HCV), either impaired or not impaired, were assessed with RS fcMRI. A statistic model including cognitive testing results was elaborated during data processing to evaluate brain networks alteration related to actual cognitive status in patients. RESULTS: Statistically significant different patterns of connectivity were found: HCV co-infection modified 17 ROIs' connectivity with 45 supra-threshold connections (p-FDR min 0.0022, max 0.0497). ROIs most involved were right pallidum, brainstem, vermian lobules 1-2 and right cerebellar lobule 10. Graph theory analysis did not demonstrate significant difference between networks, but HCV related modifications at ROI's local level were found, with particular involvement of ROIs of frontal lobe, basal ganglia and cerebellum. Increased fronto-striatal dysfunctions have been already reported as consequences of HCV infection and could reflect an additive effect. Cerebellar alterations are associated with HIV and HAND, but not with HCV infection, suggesting a synergic effect of HCV. CONCLUSION: Our study demonstrates RS fcMRI can help to understand the interactions between HIV and HCV co-infection, and our preliminary results suggest synergic effects of HCV in HIV-related brain functional modification.
  • ItemOpen AccessAccepted version Peer-reviewed
    Automated Textural Classification of Osteoarthritis Magnetic Resonance Images
    (International Society for Magnetic Resonance in Medicine, 2018-06-21) Kaggie, JD; Tovey, rob; MacKay, james; Gilbert, fiona; Gallagher, ferdia; McCaskie, andrew; Graves, martin; Kaggie, Joshua [0000-0001-6706-3442]; Tovey, Robert [0000-0001-5411-2268]; MacKay, James [0000-0001-7558-3800]; Gilbert, Fiona [0000-0002-0124-9962]; Gallagher, Ferdia [0000-0003-4784-5230]; McCaskie, Andrew [0000-0001-6476-0832]; Graves, Martin [0000-0003-4327-3052]
    Osteoarthritis (OA) is the most common cause of disability in the United Kingdom and United States. Identifying the rate of OA progression remains an important clinical and research challenge for early disease monitoring. Texture analysis of tibial subchondral bone using magnetic resonance imaging (MRI) has demonstrated the ability to discriminate between different stages of OA. This work combines texture analysis with machine learning methods (Lasso, Decision Tree, and Neural Network) to predict radiographic disease progression over 3 years, trained using data from the Osteoarthritis Initiative. We achieved high sensitivity (86%), specificity (64%) and accuracy (74%) for predictions of OA progression.
  • ItemOpen Access
    Mammographic image quality in relation to positioning of the breast: A multicentre international evaluation of the assessment systems currently used, to provide an evidence base for establishing a standardised method of assessment
    (Elsevier, 2017-11-01) Taylor, K; Parashar, D; Bouverat, G; Poulos, A; Gullien, R; Stewart, E; Aarre, R; Crystal, P; Wallis, M
    Introduction Optimum mammography positioning technique is necessary to maximise cancer detection. Current criteria for mammography appraisal lack reliability and validity with a need to develop a more objective system. We aimed to establish current international practice in assessing image quality (IQ), of screening mammograms then develop and validate a reproducible assessment tool. Methods A questionnaire sent to centres in countries undertaking population screening identified practice, participants for an expert panel (EP) of radiologists/radiographers and a testing panel (TP) of radiographers. The EP developed category criteria and descriptors using a modified Delphi process to agree definitions. The EP scored 12 screening mammograms to test agreement then a main set of 178 cases. Weighted scores were derived for each descriptor enabling calculation of numerical parameters for each new category. The TP then scored the main set. Statistical analysis included ANOVA, t-tests and Kendall's coefficient. Results 11 centres in 8 countries responded forming an EP of 7 members and TP of 44 members. The EP showed moderate agreement when the scoring the mini test set W = 0.50 p < 0.001 and the main set W = 0.55 p < 0.001, ‘posterior nipple line’ being the most difficult descriptor. The weighted total scores differentiated the 4 new categories Perfect, Good, Adequate and Inadequate (p < 0.001). Conclusion We have developed an assessment tool by Delphi consensus and weighted consensus criteria. We have successfully tabulated a range of numerical scores for each new category providing the first validated and reproducible mammography IQ scoring system.
  • ItemOpen AccessAccepted version Peer-reviewed
    Free-breathing black-blood CINE fast-spin echo imaging for measuring abdominal aortic wall distensibility: a feasibility study.
    (IOP Publishing, 2017-05-21) Lin, Jyh-Miin; Patterson, Andrew J; Chao, Tzu-Cheng; Zhu, Chengcheng; Chang, Hing-Chiu; Mendes, Jason; Chung, Hsiao-Wen; Gillard, Jonathan H; Graves, Martin J; Gillard, Jonathan [0000-0003-4787-8091]; Graves, Martin [0000-0003-4327-3052]
    The paper reports a free-breathing black-blood CINE fast-spin echo (FSE) technique for measuring abdominal aortic wall motion. The free-breathing CINE FSE includes the following MR techniques: (1) variable-density sampling with fast iterative reconstruction; (2) inner-volume imaging; and (3) a blood-suppression preparation pulse. The proposed technique was evaluated in eight healthy subjects. The inner-volume imaging significantly reduced the intraluminal artifacts of respiratory motion (p  =  0.015). The quantitative measurements were a diameter of 16.3  ±  2.8 mm and wall distensibility of 2.0  ±  0.4 mm (12.5  ±  3.4%) and 0.7  ±  0.3 mm (4.1  ±  1.0%) for the anterior and posterior walls, respectively. The cyclic cross-sectional distensibility was 35  ±  15% greater in the systolic phase than in the diastolic phase. In conclusion, we developed a feasible CINE FSE method to measure the motion of the abdominal aortic wall, which will enable clinical scientists to study the elasticity of the abdominal aorta.
  • ItemOpen AccessAccepted version Peer-reviewed
    Characterizing the distinct structural changes associated with self-reported knee injury among individuals with incident knee osteoarthritis: Data from the osteoarthritis initiative
    (Wiley-Blackwell, 2018-04) Davis, Julie E; Harkey, Matthew S; Ward, Robert J; Mackay, James W; Lu, Bing; Price, Lori Lyn; Eaton, Charles B; Barbe, Mary F; Lo, Grace H; McAlindon, Timothy E; Driban, Jeffrey B; MacKay, James [0000-0001-7558-3800]
    We aimed to characterize the agreement between distinct structural changes on magnetic resonance (MR) imaging and self-reported injury in the 12 months leading to incident common or accelerated knee osteoarthritis (KOA). We conducted a descriptive study using data from baseline and the first 4 annual visits of the Osteoarthritis Initiative. Knees had no radiographic KOA at baseline (Kellgren-Lawrence [KL]<2). We classified two groups: (1) accelerated KOA: a knee developed advanced-stage KOA (KL = 3 or 4) within 48 months and (2) common KOA: a knee increased in radiographic severity (excluding those with accelerated KOA). Adults were 1:1 matched based on sex. The index visit was when a person met the accelerated or common KOA criteria. We limited our sample to people with MR images and self-reported injury data at index visit and year prior. Among 226 people, we found fair agreement between self-reported injuries and distinct structural changes (kappa = 0.24 to 0.31). Most distinct structural changes were medial meniscal pathology. No distinct structural changes (e.g., root or radial tears) appeared to differ between adults who reported or did not report an injury; except, all subchondral fractures occurred in adults who developed accelerated KOA and reported an injury. While there is fair agreement between self-reported knee injuries and distinct structural changes, there is some discordance. Self-reported injury may represent a different construct from distinct structural changes that occur after joint trauma. Clin. Anat. 31:330-334, 2018. © 2018 Wiley Periodicals, Inc.
  • ItemOpen AccessPublished version Peer-reviewed
    Structured reporting of pelvic MRI leads to better treatment planning of uterine leiomyomas.
    (Springer Science and Business Media LLC, 2018-07) Sala, Evis; Freeman, Susan; Sala, Evis [0000-0002-5518-9360]
    Over the years, the role of the radiologist within the multidisciplinary team has evolved remarkably, with imaging providing crucial information for patient management. Through close collaboration with referring clinicians, most radiology practices now strive for their radiology reports to provide the maximum value for individualized patient care [1]. Therefore, the development of structured radiology reports has gained impetus as an essential tool towards delivering personalized medicine. In fact, structured report templates provide a platform for potentially providing clear, concise, consistent and actionable reports that can assist the referring clinician in triaging the patient to appropriate treatment [1]. The key to adding value to radiology reporting lies in the disease-specific structured reports that are developed by radiologists in collaboration with the clinical management team. However, in the era of increasing workload, the balance between a succinct, generic structured report and a time-consuming disease-specific report is important.
  • ItemOpen AccessAccepted version Peer-reviewed
    Role of PROPELLER-DWI of the prostate in reducing distortion and artefact from total hip replacement metalwork.
    (Elsevier BV, 2018-05) Czarniecki, Marcin; Caglic, Iztok; Grist, James T; Gill, Andrew B; Lorenc, Kamil; Slough, Rhys A; Priest, Andrew N; Barrett, Tristan; Grist, James [0000-0001-7223-4031]; Gill, Andrew [0000-0002-9287-9563]; Barrett, Tristan [0000-0002-1180-1474]
    OBJECTIVE: To compare image quality, artefact, and distortion in standard echo-planar imaging (EPI) with periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) for prostate magnetic resonance imaging (MRI) diffusion-weighted imaging (DWI) in patients with previous total hip replacement (THR). METHODS: 21 male subjects with a clinical suspicion for, or known prostate cancer and previous THR were scanned at 1.5 T using a phased-array body coil. DWI was obtained using single-shot EPI and PROPELLER techniques using fat saturation (PROPELLER-DWI-FS), and without (PROPELLER-DWI-NFS). Image quality (the overall impression of diagnostic quality) was compared to T2-weighted (T2WI) imaging using a 5-point Likert scale, with diffusion sequences additionally scored for artefact and distortion according to a 4-point scale, with artefact defined as the amount of prostate affected and distortion as the degree of warping of the organ. The T2W and DW image volumes were compared to produce quantitative distortion maps. A two-sample Wilcoxon test compared the qualitative scores, with inter-reader variability calculated using Cohen's kappa. RESULTS: 21 patients were included in the study, with an average age of 70.4 years and PSA 9.2 ng/ml. Hip metalwork was present bilaterally in 3 patients, left-sided in 9, and right-sided in 9. PROPELLER-DWI-FS significantly improved image quality (p < 0.01) and reduced distortion (p < 0.01) when compared to standard EP-DWI. Artefact was not shown to be significantly improved. The last 5 patients in the study were additionally imaged with PROPELLER-DWI-NFS, which resulted in a significant reduction in artefact compared to EP-DWI (p < 0.05). Quantitative distortion was significantly lower compared to EP-DWI for both PROPELLER with fat saturation (p < 0.01) and without fat saturation (p < 0.01). CONCLUSION: PROPELLER-DWI demonstrates better image quality and decreases both artefact and distortion compared to conventional echo planar sequences in patients with hip metalwork.
  • ItemOpen AccessPublished version Peer-reviewed
    Diagnostic evaluation of magnetization transfer and diffusion kurtosis imaging for prostate cancer detection in a re-biopsy population.
    (Springer Science and Business Media LLC, 2018-08) Barrett, Tristan; McLean, Mary; Priest, Andrew N; Lawrence, Edward M; Patterson, Andrew J; Koo, Brendan C; Patterson, Ilse; Warren, Anne Y; Doble, Andrew; Gnanapragasam, Vincent J; Kastner, Christof; Gallagher, Ferdia A; Barrett, Tristan [0000-0002-1180-1474]; McLean, Mary [0000-0002-3752-0179]; Warren, Anne [0000-0002-1170-7867]; Gnanapragasam, Vincent [0000-0003-4722-4207]; Gallagher, Ferdia [0000-0003-4784-5230]
    OBJECTIVE: To evaluate diffusion kurtosis imaging (DKI) and magnetisation transfer imaging (MTI) compared to standard MRI for prostate cancer assessment in a re-biopsy population. METHODS: Thirty-patients were imaged at 3 T including DKI (Kapp and Dapp) with b-values 150/450/800/1150/1500 s/mm2 and MTI performed with and without MT saturation. Patients underwent transperineal biopsy based on prospectively defined MRI targets. Receiver-operating characteristic (ROC) analyses assessed the parameters and Wilcoxon-signed ranked test assessed relationships between metrics. RESULTS: Twenty patients had ≥ 1 core positive for cancer in a total of 26 MRI targets (Gleason 3+3 in 8, 3+4 in 12, ≥ 4+3 in 6): 13 peripheral (PZ) and 13 transition zone (TZ). The apparent diffusion coefficient (ADC) and Dapp were significantly lower and the Kapp and MT ratio (MTR) significantly higher in tumour versus benign tissue (all p ≤ 0.005); ROC values 0.767-1.000. Normal TZ had: lower ADC and Dapp and higher Kapp and MTR compared to normal PZ. MTR showed a moderate correlation to Kapp (r = 0.570) and Dapp (r = -0.537) in normal tissue but a poor correlation in tumours. No parameter separated low-grade (Gleason 3+3) from high-grade (≥ 3+4) disease for either PZ (p = 0.414-0.825) or TZ (p = 0.148-0.825). CONCLUSION: ADC, Dapp, Kapp and MTR all distinguished benign tissue from tumour, but none reliably differentiated low- from high-grade disease. KEY POINTS: • MTR was significantly higher in PZ and TZ tumours versus normal tissue • K app was significantly lower and D app higher for PZ and TZ tumours • There was no incremental value for DKI/MTI over mono-exponential ADC parameters • No parameter could consistently differentiate low-grade (Gleason 3+3) from high-grade (≥ 3+4) disease • Divergent MTR/DKI values in TZ tumours suggests they offer different functional information.
  • ItemOpen AccessAccepted version Peer-reviewed
  • ItemOpen AccessPublished version Peer-reviewed
    A Comparison of Black-blood T2 Mapping Sequences for Carotid Vessel Wall Imaging at 3T: An Assessment of Accuracy and Repeatability.
    (Japanese Society for Magnetic Resonance in Medicine, 2019-01-10) Yuan, Jianmin; Patterson, Andrew J; Ruetten, Pascal PR; Reid, Scott A; Gillard, Jonathan H; Graves, Martin J; Ruetten, Pascal [0000-0001-7326-4590]; Gillard, Jonathan [0000-0003-4787-8091]; Graves, Martin [0000-0003-4327-3052]
    PURPOSE: This study is to compare the accuracy of four different black-blood T2 mapping sequences in carotid vessel wall. METHODS: Four different black-blood T2 mapping sequences were developed and tested through phantom experiments and 17 healthy volunteers. The four sequences were: 1) double inversion-recovery (DIR) prepared 2D multi-echo spin-echo (MESE); 2) DIR-prepared 2D multi-echo fast spin-echo (MEFSE); 3) improved motion-sensitized driven-equilibrium (iMSDE) prepared 3D FSE and 4) iMSDE prepared 3D fast spoiled gradient echo (FSPGR). The concordance correlation coefficient and Bland-Altman statistics were used to compare the sequences with a gold-standard 2D MESE, without blood suppression in phantom studies. The volunteers were scanned twice to test the repeatability. Mean and standard deviation of vessel wall T2, signal-to-noise (SNR), the coefficient of variance and interclass coefficient (ICC) of the two scans were compared. RESULTS: The phantom study demonstrated that T2 measurements had high concordance with respect to the gold-standard (all r values >0.9). In the volunteer study, the DIR 2D MEFSE had significantly higher T2 values than the other three sequences (P < 0.01). There was no difference in T2 measurements obtained using the other three sequences (P > 0.05). iMSDE 3D FSE had the highest SNR (P < 0.05) compared with the other three sequences. The 2D DIR MESE has the highest repeatability (ICC: 0.96, [95% CI: 0.88-0.99]). CONCLUSION: Although accurate T2 measurements can be achieved in phantom by the four sequences, in vivo vessel wall T2 quantification shows significant differences. The in vivo images can be influenced by multiple factors including black-blood preparation and acquisition method. Therefore, a careful choice of acquisition methods and analysis of the confounding factors are required for accurate in vivo carotid vessel wall T2 measurements. From the settings in this study, the iMSDE prepared 3D FSE is preferred for the future volunteer/patient scans.
  • ItemOpen AccessAccepted version Peer-reviewed
    Digital breast tomosynthesis (DBT): a review of the evidence for use as a screening tool.
    (Elsevier BV, 2016-02) Gilbert, Fiona J; Tucker, Lorraine; Young, Ken C; Gilbert, Fiona J [0000-0002-0124-9962]
    Breast screening with full-field digital mammography (FFDM) fails to detect 15-30% of cancers. This figure is higher for women with dense breasts. A new tomographic technique in mammography has been developed--digital breast tomosynthesis (DBT)--which allows images to be viewed in sections through the breast and has the potential to improve cancer detection rates. Results from retrospective reading studies comparing DBT with FFDM have been largely favourable with improvement in sensitivity and specificity. Increases in diagnostic accuracy have been reported as being independent of breast density; however there are mixed reports regarding the detection of microcalcification. Prospective screening studies using DBT with FFDM have demonstrated increased rates in cancer detection compared with FFDM alone. A reduction in false-positive recall rates has also been shown. Screening with the addition of DBT would approximately double radiation dose; however a simulated FFDM image can be generated from a DBT scan. The combination of simulated FFDM images and DBT is being evaluated within several studies and some positive results have been published. Interval cancer rates for the UK National Health Service Breast Screening Programme (NHSBSP) demonstrate the limited sensitivity of FFDM in cancer detection. DBT has the potential to increase sensitivity and decrease false-positive recall rates. It has approval for screening and diagnostics in several countries; however, there are issues with DBT as a screening tool including additional reading time, IT storage and connectivity, over-diagnosis, and cost effectiveness. Feasibility and cost-effectiveness trials are needed before the implementation of DBT in NHSBSP can be considered.
  • ItemOpen AccessAccepted version Peer-reviewed
    The evolving role of multiparametric MRI in prostate cancer work-up
    Barrett, T; Barrett, Tristan [0000-0002-1180-1474]
    Prostate cancer is the leading cause of cancer death in men after skin cancer, with an incidence expected to double by 2030 mainly due to the ageing population. However, many more men die with prostate cancer rather than from the disease, highlighting the indolent nature of many tumours. Recently, multiparametric MRI has revolutionised the work-up of prostate cancer, becoming a routine part of clinical practice and migrating earlier in the diagnostic pathway. However, the technique remains challenging, with patient-related factors, intrinsic insensitivity of MRI, protocol differences, and radiologist experienced all combining to limit its overall accuracy. Anatomical T2-weighted imaging is limited by the non-specific nature of its findings and improvements have mainly been driven by the addition of functional sequences such as diffusion-weighted imaging, dynamic contrast-enhanced MRI and spectroscopy. In the absence of validated circulating biomarkers, only functional imaging currently offers the potential for further improvements in lesion detection and characterisation, with the additional advantages of providing whole gland coverage of the prostate and being non-invasive. An overview of the evolving role of prostate multiparametric MRI is provided, along with its strengths and weaknesses and an exploration of how it can help overcome limitations in the traditional work-up of patients.
  • ItemOpen AccessPublished version Peer-reviewed
    Lesion Targeted CT-Guided Transgluteal Prostate Biopsy in Combination With Prebiopsy MRI in Patients Without Rectal Access.
    (Elsevier BV, 2017-01) Caglic, Iztok; Breznik, S; Matela, J; Barrett, T; Barrett, Tristan [0000-0002-1180-1474]
    With prostate and colorectal malignancies being the most common cancers in men, elevated prostate specific antigen (PSA) in patients without rectal access due to prior surgery poses a diagnostic dilemma. We report the first use of CT-guided biopsy in combination with prebiopsy MRI in 2 patients with a clinical suspicion of prostate cancer and no rectal access. In both cases, a diagnostic multiparametric MRI of the prostate was performed to detect and to localize a potential suspicious lesion. The localization served as a cognitive map for guiding needle placement using a CT-guided transgluteal approach.
  • ItemOpen AccessAccepted version Peer-reviewed
    Personalised screening: is this the way forward?
    (Elsevier BV, 2018-04) Gilbert, FJ; Selamoglu, A; Gilbert, Fiona [0000-0002-0124-9962]
    Screening with mammography has been implemented in many countries across the world with most offering 2-yearly examinations between the ages of 50-69 years. Robust modelling tools that include breast density and single nucleotide polymorphisms (SNPs) have been developed to predict which women are most likely to develop breast cancer. Mammographic sensitivity is poor in women with the densest category of breast tissue, and even women with heterogeneously dense tissue may benefit from additional supplemental imaging. Digital breast tomosynthesis (DBT), automated breast ultrasound (ABUS), contrast-enhanced mammography (CESM) or abbreviated (ABB) magnetic resonance imaging (MRI) all offer the opportunity to increase cancer detection, especially in women with dense breasts at increased risk of cancer. DBT increases cancer detection by around 15% with a corresponding reduction in recall rates; ABUS has been shown to increase cancer detection by between 2-4/1,000 depending on the cohort being examined and results in increased recalls, which tend to fall in subsequent screening rounds; CESM has very high sensitivity almost matching MRI with slightly improved specificity; ABB-MRI has been shown to be virtually equivalent to standard protocol MRI examinations, making this a technique that could be considered as a screening tool in high-risk women. This article reviews the literature to establish the current status of these techniques. The cost-effectiveness of these techniques requires further investigation and screening trials should report the nature of any additional tumours that are found.
  • ItemOpen AccessPublished version Peer-reviewed
    A method for mapping and quantifying whole organ diffusion-weighted image distortion in MR imaging of the prostate.
    (Springer Science and Business Media LLC, 2017-10-05) Gill, Andrew B; Czarniecki, Marcin; Gallagher, Ferdia A; Barrett, Tristan; Gill, Andrew [0000-0002-9287-9563]; Gallagher, Ferdia [0000-0003-4784-5230]; Barrett, Tristan [0000-0002-1180-1474]
    A computational algorithm was designed to produce a measure of DW image distortion across the prostate. This algorithm was tested and validated on virtual phantoms incorporating known degrees and distributions of distortion. A study was then carried out on DW image volumes from three sets of 10 patients who had been imaged previously. These volumes had been radiologically assessed to have, respectively, 'no distortion' or 'significant distortion' or the potential for 'significant distortion' due to susceptibility effects from hip prostheses. Prostate outlines were drawn on a T2-weighted (T2W) image 'gold-standard' volume and on an ADC image volume derived from DW images acquired over the same region. The algorithm was then applied to these outlines to quantify and map image distortion. The proposed method correctly reproduced known distortion values and distributions in virtual phantoms. It also successfully distinguished between the three groups of patients: mean distortion in 'non-distorted' image volumes, 1.942 ± 0.582 mm; 'distorted', 4.402 ± 1.098 mm; and 'hip patients' 8.083 ± 4.653 mm; P < 0.001. This work has demonstrated and validated a means of quantifying and mapping image distortion in clinical prostate MRI cases.
  • ItemOpen AccessPublished version Peer-reviewed
    Age-related changes in the effects of strength training on lower leg muscles in healthy individuals measured using MRI
    (BMJ Journals, 2017-07-20) Psatha, M; Wu, Z; Gammie, F; Ratkevicius, A; Wackerhage, H; Redpath, TW; Gilbert, FJ; Meakin, JR; Aspden, RM; Gilbert, Fiona [0000-0002-0124-9962]
    BACKGROUND: We previously measured the rate of regaining muscle strength during rehabilitation of lower leg muscles in patients following lower leg casting. Our primary aim in this study was to measure the rate of gain of strength in healthy individuals undergoing a similar training regime. Our secondary aim was to test the ability of MRI to provide a biomarker for muscle function. METHODS: Men and women were recruited in three age groups: 20-30, 50-65 and over 70 years. Their response to resistance training of the right lower leg twice a week for 8 weeks was monitored using a dynamometer and MRI of tibialis anterior, soleus and gastrocnemius muscles at 2 weekly intervals to measure muscle size (anatomical cross-sectional area (ACSA)) and quality (T2 relaxation). Forty-four volunteers completed the study. RESULTS: Baseline strength declined with age. Training had no effect in middle-aged females or in elderly men in dorsiflexion. Other groups significantly increased both plantarflexion and dorsiflexion strength at rates up to 5.5 N m week(-1) in young females in plantarflexion and 1.25 N m week(-1) in young males in dorsiflexion. No changes were observed in ACSA or T2 in any age group in any muscle. CONCLUSION: Exercise training improves muscle strength in males at all ages except the elderly in dorsiflexion. Responses in females were less clear with variation across age and muscle groups. These results were not reflected in simple MRI measures that do not, therefore, provide a good biomarker for muscle atrophy or the efficacy of rehabilitation.