scholarly journals Prospective Image Quality and Lesion Assessment in the Setting of MR-Guided Radiation Therapy of Prostate Cancer on an MR-Linac at 1.5 T: A Comparison to a Standard 3 T MRI

Cancers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1533
Author(s):  
Haidara Almansour ◽  
Saif Afat ◽  
Victor Fritz ◽  
Fritz Schick ◽  
Marcel Nachbar ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Image Quality ◽  
Outcome Measures ◽  
Quality Criteria ◽  
Lesion Size ◽  
Geometric Distortion ◽  
Diagnostic Confidence ◽  
Prostate Imaging ◽  
Lesion Conspicuity

The objective of this study is to conduct a qualitative and a quantitative image quality and lesion evaluation in patients undergoing MR-guided radiation therapy (MRgRT) for prostate cancer on a hybrid magnetic resonance imaging and linear accelerator system (MR-Linac or MRL) at 1.5 Tesla. This prospective study was approved by the institutional review board. A total of 13 consecutive patients with biopsy-confirmed prostate cancer and an indication for MRgRT were included. Prior to radiation therapy, each patient underwent an MR-examination on an MRL and on a standard MRI scanner at 3 Tesla (MRI3T). Three readers (two radiologists and a radiation oncologist) conducted an independent qualitative and quantitative analysis of T2-weighted (T2w) and diffusion-weighted images (DWI). Qualitative outcome measures were as follows: zonal anatomy, capsule demarcation, resolution, visibility of the seminal vesicles, geometric distortion, artifacts, overall image quality, lesion conspicuity, and diagnostic confidence. All ratings were performed on an ordinal 4-point Likert scale. Lesion conspicuity and diagnostic confidence were firstly analyzed only on MRL. Afterwards, these outcome parameters were analyzed in consensus with the MRI3T. Quantitative outcome measures were as follows: anteroposterior and right left diameter of the prostate, lesion size, PI-RADS score (Prostate Imaging—Reporting and Data System) and apparent diffusion coefficient (ADC) of the lesions. Intergroup comparisons were computed using the Wilcoxon-sign rank test and t tests. A post-hoc regression analysis was computed for lesion evaluation. Finally, inter-/intra-reader agreement was analyzed using the Fleiss kappa and intraclass correlation coefficient. For T2w images, the MRL showed good results across all quality criteria (median 3 and 4). Furthermore, there were no significant differences between MRL and MRI3T regarding capsule demarcation or geometric distortion. For the DWI, the MRL performed significantly less than MRI3T across most image quality criteria with a median ranging between 2 and 3. However, there were no significant differences between MRL and MRI3T regarding geometric distortion. In terms of lesion conspicuity and diagnostic confidence, inter-reader agreement was fair for MRL alone (Kappa = 0.42) and good for MRL in consensus with MRI3T (Kappa = 0.708). Thus, lesion conspicuity and diagnostic confidence could be significantly improved when reading MRL images in consensus with MRI3T (Odds ratio: 9- to 11-fold for the T2w images and 5- to 8–fold for the DWI) (p < 0.001). For measures of lesion size, anterior-posterior and right-left prostate diameter, inter-reader and intersequence agreement were excellent (ICC > 0.90) and there were no significant differences between MRL and MRI3T among all three readers. In terms of Prostate Imaging Reporting and Data System (PIRADS) scoring, no significant differences were observed between MRL and MRI3T. Finally, there was a significant positive linear relationship between lesion ADC measurements (r = 0.76, p < 0.01) between the ADC values measured on both systems. In conclusion, image quality for T2w was comparable and diagnostic even without administration of spasmolytic- or contrast agents, while DWI images did not reach diagnostic level and need to be optimized for further exploitation in the setting of MRgRT. Diagnostic confidence and lesion conspicuity were significantly improved by reading MRL in consensus with MRI3T which would be advisable for a safe planning and treatment workflow. Finally, ADC measurements of lesions on both systems were comparable indicating that, lesion ADC as measured on the MRL could be used as a biomarker for evaluation of treatment response, similar to examinations using MRI3T.

scholarly journals Accelerated T2-Weighted TSE Imaging of the Prostate Using Deep Learning Image Reconstruction: A Prospective Comparison with Standard T2-Weighted TSE Imaging

Cancers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 3593
Author(s):  
Sebastian Gassenmaier ◽  
Saif Afat ◽  
Marcel Dominik Nickel ◽  
Mahmoud Mostapha ◽  
Judith Herrmann ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Deep Learning ◽  
Image Reconstruction ◽  
Image Quality ◽  
Acquisition Time ◽  
Noise Levels ◽  
Diagnostic Confidence ◽  
Prospective Comparison ◽  
The Impact ◽  
Lesion Conspicuity

Multiparametric MRI (mpMRI) of the prostate has become the standard of care in prostate cancer evaluation. Recently, deep learning image reconstruction (DLR) methods have been introduced with promising results regarding scan acceleration. Therefore, the aim of this study was to investigate the impact of deep learning image reconstruction (DLR) in a shortened acquisition process of T2-weighted TSE imaging, regarding the image quality and diagnostic confidence, as well as PI-RADS and T2 scoring, as compared to standard T2 TSE imaging. Sixty patients undergoing 3T mpMRI for the evaluation of prostate cancer were prospectively enrolled in this institutional review board-approved study between October 2020 and March 2021. After the acquisition of standard T2 TSE imaging (T2S), the novel T2 TSE sequence with DLR (T2DLR) was applied in three planes. Overall, the acquisition time for T2S resulted in 10:21 min versus 3:50 min for T2DLR. The image evaluation was performed by two radiologists independently using a Likert scale ranging from 1–4 (4 best) applying the following criteria: noise levels, artifacts, overall image quality, diagnostic confidence, and lesion conspicuity. Additionally, T2 and PI-RADS scoring were performed. The mean patient age was 69 ± 9 years (range, 49–85 years). The noise levels and the extent of the artifacts were evaluated to be significantly improved in T2DLR versus T2S by both readers (p < 0.05). Overall image quality was also evaluated to be superior in T2DLR versus T2S in all three acquisition planes (p = 0.005–<0.001). Both readers evaluated the item lesion conspicuity to be superior in T2DLR with a median of 4 versus a median of 3 in T2S (p = 0.001 and <0.001, respectively). T2-weighted TSE imaging of the prostate in three planes with an acquisition time reduction of more than 60% including DLR is feasible with a significant improvement of image quality.

PSA levels, PSA doubling time, Gleason score and prior therapy cannot predict measured uptake of [68Ga]PSMA-HBED-CC lesion uptake in recurrent/metastatic prostate cancer

2017 ◽  
Vol 56 (06) ◽  
pp. 225-232 ◽  
Author(s):  
David Pfister ◽  
Natascha Drude ◽  
Felix Mottaghy ◽  
Florian Behrendt ◽  
Frederik Verburg
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Lymph Node ◽  
Androgen Deprivation Therapy ◽  
Gleason Score ◽  
Doubling Time ◽  
Lesion Size ◽  
Tracer Uptake ◽  
Androgen Deprivation ◽  
Pet Ct

SummaryAim: To assess whether clinical prostate cancer (PCA) related factors and therapy status can predict the degree of tracer uptake on [68Ga]PSMA-HBED-CC PET/CT.Materials & methods: We retrospectively studied 124 patients with recurrent an/or metastatic PCA who underwent [68Ga]PSMAHBED-CC PET/CT. The maximum standardized uptake value (SUVmax) was determined in the prostate bed as well as in three size categories (≤ 5 mm, > 5–15 mm, > 15 mm) in pelvic lymph node, extrapelvic lymph node, bone and visceral metastases.Results: Significant positive correlations between lesion size and SUVmax were found in pelvic lymph node metastases > 5 -≤15 mm (Spearmans rho = 0.502, p = 0.002) as well as in extrapelvic lymph node metastases5 mm (rho = 0.314, p = 0.033) and > 5 ≤-15 mm (rho = 0.614, p < 0.001). SUVmax tended to be higher in the largest diameter category in each anatomic station than in the middle and lower categories. We were unable to find evidence for a relationship between SUVmax and PSA, PSAdt, Gleason score, androgen deprivation therapy, radiation therapy or chemotherapy status.Conclusion: Measured tracer uptake in [68Ga]PSMA-HBED-CC PET/CT in patients with recurrent/metastasized prostate cancer is significantly influenced by lesion size as a result of partial volume effects in the very small lesions. Clinical indicators of aggressive prostate cancer behaviour such as PSA levels, PSA doubling time or the Gleason score of the primary tumour, as well as the androgen deprivation therapy, radiation therapy or chemotherapy status are not related to measured tracer uptake.

scholarly journals Qualitative and quantitative comparison of image quality between single-shot echo-planar and interleaved multi-shot echo-planar diffusion-weighted imaging in female pelvis

2019 ◽  
Vol 30 (4) ◽  
pp. 1876-1884
Author(s):  
He An ◽  
Xiaodong Ma ◽  
Ziyi Pan ◽  
Hua Guo ◽  
Elaine Yuen Phin Lee
Keyword(s):  
Image Quality ◽  
Diffusion Weighted Imaging ◽  
Geometric Distortion ◽  
Single Shot ◽  
Post Processing ◽  
Female Pelvis ◽  
Diffusion Weighted ◽  
Noise Ratio ◽  
Echo Planar ◽  
Lesion Conspicuity

Abstract Objectives To qualitatively and quantitatively compare the image quality between single-shot echo-planar (SS-EPI) and multi-shot echo-planar (IMS-EPI) diffusion-weighted imaging (DWI) in female pelvis Methods This was a prospective study involving 80 females who underwent 3.0T pelvic magnetic resonance imaging (MRI). SS-EPI and IMS-EPI DWI were acquired with 3 b values (0, 400, 800 s/mm2). Two independent reviewers assessed the overall image quality, artifacts, sharpness, and lesion conspicuity based on a 5-point Likert scale. Regions of interest (ROI) were placed on the endometrium and the gluteus muscles to quantify the signal intensities and apparent diffusion coefficient (ADC). Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and geometric distortion were quantified on both sequences. Inter-rater agreement was assessed using κ statistics and Kendall test. Qualitative scores were compared using Wilcoxon signed-rank test and quantitative parameters were compared with paired t test and Bland-Altman analysis. Results IMS-EPI demonstrated better image quality than SS-EPI for all aspects evaluated (SS-EPI vs. IMS-EPI: overall quality 3.04 vs. 4.17, artifacts 3.09 vs. 3.99, sharpness 2.40 vs. 4.32, lesion conspicuity 3.20 vs. 4.25; p < 0.001). Good agreement and correlation were observed between two reviewers (SS-EPI κ 0.699, r 0.742; IMS-EPI κ 0.702, r 0.789). IMS-EPI showed lower geometric distortion, SNR, and CNR than SS-EPI (p < 0.050). There was no significant difference in the mean ADC between the two sequences. Conclusion IMS-EPI showed better image quality with lower geometric distortion without affecting the quantification of ADC, though the SNR and CNR decreased due to post-processing limitations. Key Points • IMS-EPI showed better image quality than SS-EPI. • IMS-EPI showed lower geometric distortion without affecting ADC compared with SS-EPI. • The SNR and CNR of IMS-EPI decreased due to post-processing limitations.

scholarly journals ESUR/ESUI consensus statements on multi-parametric MRI for the detection of clinically significant prostate cancer: quality requirements for image acquisition, interpretation and radiologists’ training

2020 ◽  
Vol 30 (10) ◽  
pp. 5404-5416 ◽  
Author(s):  
Maarten de Rooij ◽  
Bas Israël ◽  
Marcia Tummers ◽  
Hashim U. Ahmed ◽  
Tristan Barrett ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Image Quality ◽  
Image Quality Assessment ◽  
Image Acquisition ◽  
Quality Criteria ◽  
Performance Assessments ◽  
Delphi Consensus ◽  
Prostate Mri ◽  
Consensus Statements ◽  
Hands On

Abstract Objectives This study aims to define consensus-based criteria for acquiring and reporting prostate MRI and establishing prerequisites for image quality. Methods A total of 44 leading urologists and urogenital radiologists who are experts in prostate cancer imaging from the European Society of Urogenital Radiology (ESUR) and EAU Section of Urologic Imaging (ESUI) participated in a Delphi consensus process. Panellists completed two rounds of questionnaires with 55 items under three headings: image quality assessment, interpretation and reporting, and radiologists’ experience plus training centres. Of 55 questions, 31 were rated for agreement on a 9-point scale, and 24 were multiple-choice or open. For agreement items, there was consensus agreement with an agreement ≥ 70% (score 7–9) and disagreement of ≤ 15% of the panellists. For the other questions, a consensus was considered with ≥ 50% of votes. Results Twenty-four out of 31 of agreement items and 11/16 of other questions reached consensus. Agreement statements were (1) reporting of image quality should be performed and implemented into clinical practice; (2) for interpretation performance, radiologists should use self-performance tests with histopathology feedback, compare their interpretation with expert-reading and use external performance assessments; and (3) radiologists must attend theoretical and hands-on courses before interpreting prostate MRI. Limitations are that the results are expert opinions and not based on systematic reviews or meta-analyses. There was no consensus on outcomes statements of prostate MRI assessment as quality marker. Conclusions An ESUR and ESUI expert panel showed high agreement (74%) on issues improving prostate MRI quality. Checking and reporting of image quality are mandatory. Prostate radiologists should attend theoretical and hands-on courses, followed by supervised education, and must perform regular performance assessments. Key Points • Multi-parametric MRI in the diagnostic pathway of prostate cancer has a well-established upfront role in the recently updated European Association of Urology guideline and American Urological Association recommendations. • Suboptimal image acquisition and reporting at an individual level will result in clinicians losing confidence in the technique and returning to the (non-MRI) systematic biopsy pathway. Therefore, it is crucial to establish quality criteria for the acquisition and reporting of mpMRI. • To ensure high-quality prostate MRI, experts consider checking and reporting of image quality mandatory. Prostate radiologists must attend theoretical and hands-on courses, followed by supervised education, and must perform regular self- and external performance assessments.

scholarly journals Prostate MRI quality: a critical review of the last 5 years and the role of the PI-QUAL score

2021 ◽  
pp. 20210415
Author(s):  
Francesco Giganti ◽  
Veeru Kasivisvanathan ◽  
Alex Kirkham ◽  
Shonit Punwani ◽  
Mark Emberton ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Image Quality ◽  
Critical Review ◽  
Resonance Imaging ◽  
Technical Standards ◽  
Prostate Imaging ◽  
Technical Requirements ◽  
Patient Preparation ◽  
Clinically Significant

There is increasing interest in the use of multiparametric magnetic resonance imaging (mpMRI) in the prostate cancer pathway. The European Association of Urology (EAU) and the British Association of Urological Surgeons (BAUS) now advise mpMRI prior to biopsy, and the Prostate Imaging Reporting and Data System (PI-RADS) recommendations set out the minimal technical requirements for the acquisition of mpMRI of the prostate. The widespread and swift adoption of this technique has led to variability in image quality. Suboptimal image acquisition reduces the sensitivity and specificity of mpMRI for the detection and staging of clinically significant prostate cancer. This critical review outlines the studies aimed at improving prostate MR quality that have been published over the last 5 years. These span from the use of specific MR sequences, magnets and coils to patient preparation. The rates of adherence of prostate mpMRI to technical standards in different cohorts across the world are also discussed. Finally, we discuss the first standardised scoring system (i.e., Prostate Imaging Quality, PI-QUAL) that has been created to evaluate image quality, although further iterations of this score are expected in the future.

scholarly journals Exploration of Optimal Reconstruction Parameters for 18F-FDG Total-body PET/CT with Ultra-low Activity Injection

2021 ◽  
Author(s):  
Xiuli Sui ◽  
Hui Tan ◽  
Haojun Yu ◽  
Yiqiu Zhang ◽  
Pengcheng Hu ◽  
...  
Keyword(s):  
Image Quality ◽  
Expectation Maximization ◽  
Lesion Size ◽  
Pet Ct ◽  
Quality Image ◽  
Optimal Reconstruction ◽  
Total Body ◽  
Low Activity ◽  
Lesion Conspicuity ◽  
Reconstruction Time

Abstract PURPOSE To explorer the optimal reconstruction parameters in oncologic 18 F-FDG total-body PET/CT studies with ultra-low activity injection. METHODS A total of 204 reconstructed PET images of 34 patients with a total of 58 lesions were analyzed by two experienced nuclear medicine physicians. Images were reconstructed with ordered subset expectation maximization (OSEM) algorithm (2 and 3 iterations) including time-of-flight (TOF) and point spread function (PSF) corrections and regularization ordered subset expectation maximization (ROSEM) (b-values of 0.3, 0.4, 0.5, and 0.6). General image quality was assessed using the five-point method including overall image quality, image clarity, noise, and lesion conspicuity. Image noise, signal-to-noise ratio, lesion size, SUVmax, SUVpeak and T/N were quantitatively analyzed by the third reader who did not participate in subjective image assessment. RESULTS In objective image quality indicators, noise decreased and a continuous increase of SNR with incremental β-values (0.3,0.4, 0.5 and 0.6) compared with OSEM3. In subjective image quality, OSEM2, ROSEM0.5 and ROSEM0.6 scored higher (all P<0.001) in overall image quality, image contrast and noise. The scores of ROSEM reconstructions were all higher in lesion conspicuity compared with OSEM3 (all P<0.001). In lesion detectability, SUVmax, SUVpeak and T/N increase with β value of ROSEM increase. Compared with OSEM3, there was a negative correlation between lesion size and the percentage increase of SUVpeak in OSEM2 and ROSEM reconstructions (all P<0.01). CONCLUSION In clinical practice, we recommended OSEM reconstruction with 3 iterations with a relatively short reconstruction time and we recommend ROSEM algorithm with b of 0.5 when reconstruction time is not considered.

MRI-TRUS fusion-guided biopsy in obese patients: Does it reduce risk of prostate cancer upgrade on final pathology compared to systematic 12-core biopsy?

2019 ◽  
Vol 37 (7_suppl) ◽  
pp. 110-110
Author(s):  
Samuel A Gold ◽  
Jonathan Bloom ◽  
Amir H Lebastchi ◽  
Graham Hale ◽  
Sherif Mehralivand ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Clinical Stage ◽  
Lesion Size ◽  
Normal Weight ◽  
Lesion Location ◽  
Prostate Imaging ◽  
Prostate Biopsies ◽  
Increased Risk ◽  
Prostate Size ◽  
Reduce Risk

110 Background: Epidemiologic data suggests a link between obesity and increased risk of aggressive prostate cancer (PCa). Therefore, the accurate detection of prostate cancer is paramount in obese men. We sought to characterize the PCa lesions seen on multiparametric magnetic resonance imaging (mpMRI) in both obese (OB) and non-obese (nOB) patients. In addition, we examined whether obesity affects the accuracy of fusion biopsy (FBx) versus systematic biopsy (SBx). Methods: Data from patients who underwent FBx, SBx, or both, and subsequent prostatectomy at a single institution between 2007-2017 were reviewed. Men were stratified into three groups based on body mass index (BMI): normal weight (18.5-24.9), overweight (25.0-29.9), and obese (≥30.0). mpMRIs were analyzed to determine prostate size, lesion size, lesion location, and evidence of ≥T3 disease. FBx and SBx were compared to prostatectomy specimens. These variables were then analyzed between the OB and nOB groups. Results: 487 patients were included: 109 (19%) normal weight, 266 (48%) overweight, and 185 (33%) obese. No statistical differences were noted in age, PSA, or clinical stage. mpMRI showed similar prostate size, index and total lesion diameter, lesion location, and Prostate Imaging Reporting and Data System (PIRADS) score between BMI categories. In OB patients, FBx was better able to predict final Gleason score (GS) than SBx, 60% vs 47%, p = 0.0474, OR 1.67 (1.00-2.80). The rate of upgrading after SBx was higher for OB men versus nOB men, 44% vs 34%, p = 0.034, OR 1.52 (1.01-2.29). However, risk of upgrading returned to that of nOB men with FBx, 20% vs 17%, p = 0.538, OR 1.21 (0.658-2.23). Conclusions: FBx is a more accurate measure of the true GS in OB patients than SBx, and there is a significantly greater risk of underrepresenting PCa on SBx in OB patients. These findings were not associated with differences in prostate sizes and lesion characteristics on mpMRI. This suggests that obesity may cause technical challenges with prostate biopsies that may be overcome by improved visualization and targeting of FBx.

395: Nomogram Predicting 10 year Life Expectancy after Radical Prostatectomy or Radiation Therapy for Prostate Cancer

2007 ◽  
Vol 177 (4S) ◽  
pp. 131-132 ◽  
Author(s):  
Jochen Wafz ◽  
Andrea Gallina ◽  
Aldo M. Bocciardi ◽  
Sascha Ahyai ◽  
Paul Perrotta ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Radical Prostatectomy ◽  
Life Expectancy
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