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MRI of the normal anatomy of the cervix in a pre-menopausal 35-year-old patient with endometriosis. a Sagittal T2-weighted BLADE sequence. b Sagittal T2-weighted conventional TSE sequence. The cervical mucosa and stroma are more sharpely delineated on the BLADE image (a); however, SNR and CNR are higher on the conventional TSE image in b
Source publication
Objectives:
To prospectively compare the diagnostic performance of a non-Cartesian k-space sampling T2-weighted TSE BLADE sequence with a conventional T2-weighted TSE sequence in female pelvic organs.
Methods:
Forty-seven patients with sonographically indeterminate adnexal masses or uterine lesions underwent sagittal BLADE and conventional TSE a...
Citations
... The collected data is subjected to motion correction, rotation correction, and displacement correction for image reconstruction, which has a weakening effect on respiratory motion artifacts during abdominal scanning. Due to its unique K-space sampling method, the presence of radial artifacts often interferes with the diagnosis of images [13] (Figure 2). ...
Objective
To compare the image quality of HASTE-GRE-Separated, HASTE-TSE-Separated, TSE-BLADE, and TSE sequences in gastric T2WI, and explore the optimal imaging scheme for gastric T2WI.
Method
25 patients with gastric cancer (17 males and 8 females) were included and scanned using HASTE-GRE-Separated, HASTE-TSE-Separated, TSE-BLADE, and TSE sequences on 3.0T magnetic resonance imaging. Calculate the SNR of the lesion, the signal intensity ratio of the lesion to water, and the CNR. Two abdominal diagnostic physicians (with 15 and 5 years of diagnostic experience, respectively) rated the image quality according to the 5-point method. The criteria were as follows: 5 = excellent (clear display of gastric wall and perigastric fat spaces, clear display of cancer margins, clear boundary between gastric blood vessels and lymph nodes), 4 = good (slight artifacts in gastric wall and perigastric fat spaces, and cancer lesion boundaries can be determined), 3 = Moderate (gastric wall display is fair, perigastric fat spaces are not clear, and cancer margins are blurry), 2 = Poor (gastric wall display is not clear, but cancer location is difficult to determine boundaries), and 1 = Poor (gastric wall and cancer location are not clear, making it difficult to determine cancer location and boundaries). All quantitative and qualitative parameters were analyzed using One way ANOVA and Kruskal Wallis one-way ANOVA, with Bonferroni correction used for pairwise comparisons between groups. Apply Kappa analysis to analyze the consistency of scores between two physicians.
Results
Objective quantitative parameter analysis showed that there were statistical differences in SNR and CNR among the four types of T2WI in the stomach (F = 4.709, P < 0.05; F = 4.164, P < 0.05). The SNR of the HASTE-TSE-Separated sequence was higher than that of the TSE sequence (P < 0.05). The CNR of the HASTE-GRE-Separated sequence was higher than that of the TSE sequence (P < 0.05). The signal strength ratio of the HASTE-GRE-Separated sequence is not as good as that of the TSE-BLADE sequence (P < 0.05). The signal intensity ratio of HASTE-GRE-Separated and HASTE-TSE-Separated sequences showed no significant difference (P > 0.05), but the HASTE-TSE-Separated sequence showed a slightly higher tissue CNR. The subjective evaluation scores of HASTE-GRE-Separated and HASTE-TSE-Separated sequences [(4.52 ± 0.59) and (4.64 ± 0.49) scores] were significantly higher than those of TSE-BLADE and TSE [(3.16 ± 0.80) and (3.04 ± 1.02) scores, (F = 32.47, P < 0.001)]. The HASTE-TSE-Separated sequence image has the highest score. The subjective scores of both physicians for the four sequences showed good consistency.
Conclusion
Although the signal strength of the HASTE sequence is not as strong as that of the TSE-BLADE and TSE sequences, the HASTE sequence has a faster imaging speed and fewer motion artifacts, especially the appearance of the HASTE-TSE-Separated imaging sequence, which further improves the imaging quality of traditional HASTE and has great potential for application in gastric MR T2WI imaging.
... The T2-PROPELLER technique uses a sampling trajectory oriented radially to the centre of k-space, producing a blade-like order of acquisition and can reduce sensitivity to motion, field inhomogeneity, and eddy current artefacts. 10,11 There is some early evidence of T2-PROPELLER imaging demonstrating equivalent image quality and lesion detection in prostate imaging, however, it is unclear whether the sequence can be used to replace FRFSE/TSE acquisitions routinely. 8,12 The aim of this study was therefore primarily to compare T2-PROPELLER image quality to that of T2-FRFSE sequences and, secondarily, to assess its ability to detect lesions on prostate MRI in the presence and absence of motion artefact. ...
... Previous studies with around half the number of patients to ours have also shown that FRFSE equivalent T2-weighted sequences demonstrate increased T2 contrast compared to the T2-PROPELLER equivalent sequences. 8,11,12 However, consistent with our results, in prostate studies, the lower contrast of T2-PROPELLER imaging was offset by a reduction in artefact and therefore no overall difference was found for prostate lesion detection. 8,12 For lesion detection, Meier-Schroers, et al 12 showed PROPELLER-sequences identified a slightly higher proportion of lesions at 98.2% versus 92.7% for T2-TSE, similar to our increased PPV for lesion detection with T2-PROPELLER at 97.7% compared to 93.2% with T2-FRFSE, conversely, Rosenkrantz, et al 8 demonstrated a slight increased lesion detection for standard T2 compared to BLADEsequences. ...
Purpose
The primary objective was to compare T2-FRFSE and T2-PROPELLER sequences for image quality. The secondary objective was to compare the ability to detect prostate lesions at MRI in the presence and absence of motion artefact using the 2 sequences.
Methods
99 patients underwent 3 T MRI examination of the prostate, including T2-FRFSE and T2-PROPELLER sequences. All patients underwent prostate biopsy. Two independent readers rated overall image quality, presence of motion artefact, and blurring for both sequences using a 5-point Likert scale. Scores were compared for the whole group and for subgroups with and without significant motion artefact. Outcome for lesion detection at an MRI threshold of PI-RADS score ≥3 was compared between T2-FRFSE and T2-PROPELLER.
Results
The overall image quality was not significantly different between T2-FRFSE and T2-PROPELLER sequences (3.74 vs. 3.93, p = 0.275). T2-PROPELLER recorded a lesser degree of motion artefact (score 4.53 vs. 3.78, p <0.0001), but demonstrated greater image blurring (score 3.29 vs. 3.73, p <0.001). However, in a subgroup of patients with significant motion artefact on T2-FRFSE, the T2-PROPELLER sequence demonstrated significantly higher image quality (3.46 vs. 2.49, p <0.001). T2-FRFSE and T2-PROPELLER showed comparable positive predictive values for lesion detection at 93.2% and 97.7%, respectively.
Conclusions
T2-PROPELLER provides higher quality imaging in the presence of motion artefact, but T2-FRFSE is preferred in the absence of motion. T2-PROPELLER is therefore recommended as a secondary T2 sequence when imaging requires repeat acquisition due to motion artefact.
... In patients with large amounts of ascites or in pregnant patients with amniotic fluid, flow-related artefacts may also cause additional image degradation [6]. These movement or ghosting artefacts can result in poorly defined organ contours and blurred anatomic structures, thus reducing detection of pathological lesions [7]. ...
Objectives
To assess whether with recent MR technology current patient preparation literature recommendations for female pelvic MRI are still valid and how they are influencing the position of the female pelvic organs, image quality, and diagnostic confidence.Methods
This prospective study was performed in two centres. The effects of bladder filling (empty, moderate, full; n = 26), fasting, saturation band (n = 25), and menstrual cycle (n = 25) were assessed in healthy subjects in centre 1, while the effect of intravenous glucagon application was evaluated in 20 patients with benign conditions in centre 2. Images of the pelvis were acquired using 1.5-T MRI with T2-weighted turbo spin echo imaging in sagittal and (angulated) transaxial planes. The analysis was conducted hierarchically using paired Wilcoxon tests with an alpha significance level of 0.05.ResultsUrinary bladder filling influenced the cervix-to-uterine angle (p < 0.001) but had no clear effect on image quality (p > 0.05). A moderately full bladder provided the best delineation of fat between the bladder and uterus (p = 0.0009). A full bladder resulted in highest ovarian displacement (p = 0.0059). Timing within the menstrual cycle did not influence the depiction of zonal anatomy (p > 0.05). Fasting (p < 0.02) and saturation bands (p < 0.001) had a positive effect on image quality. Glucagon was associated with decreased MRI artefacts (p = 0.002).Conclusion
Fasting, antispasmodic agents, and saturation bands improved MR image quality and are recommended for female pelvic MRI. Urinary bladder filling influenced the cervix-to-uterine angle, but had no clear effect on image quality.Key Points
• Fasting, saturation band, and glucagon injection significantly reduced bowel movement artefacts.
• Depiction of the anatomical details of the uterus was not influenced by the timing of MRI within the menstrual cycle.
• Although bladder filling did not impact diagnostic capabilities in healthy volunteers, in clinical practice, it may be useful to examine patients with a moderately full bladder, to reduce diagnostic inaccuracies.
... One approach to overcoming this is to use non-Cartesian sampling [1,5]. As opposed to standard Cartesian sampling, non-Cartesian sampling confers better motion immunity and compensates for signal non-uniformity [4][5][6]. In particular, the Periodically Rotated Overlapping Parallel Lines with Enhanced Reconstruction (PROPELLER) technique has shown to be highly valuable. ...
Objective: To evaluate T2-weighted BLADE tecnique for evaluating intra-abdominal organs and lesions, especially the gastrointestinal wall and pathologies, and to compare the findings with HASTE.
Material and Methods: Sixty patients (mean age: 47.2 years, range 19-88) (32 males, 28 females) referred to our institution for upper abdominal Magnetic Resonance Imaging (MRI) examinations with various indications between January 2015 and May 2015 were included in our study. All examinations were performed on a 1.5 Tesla MR device and no anti-peristaltic drug was administered. Images were retrospectively and independently evaluated by two radiologists. A qualitative evaluation was performed to assess images regarding the presence of artifacts and diagnostic quality, the anatomical detail of the upper abdominal organs and structures (contour sharpness, contrast of tissue, parenchyma and internal wall structure) and any present pathologies and lesions in the organs (lesion contour sharpness and size, internal structure properties, morphological characteristics). A quantitative evaluation was performed to calculate the contrast-to-muscle ratios (CMR) of the internal organs and lesions. The distribution of the variables was statistically checked by Kolmogorov Smirnov test. Paired-samples t- test was used for quantitative data.
Results: BLADE was significantly associated with reduced artifacts (p <0.0001) and increased image quality compared with HASTE. The highest agreement between both observers was that motion artifacts were reduced (Gwet's AC2 = 0.94). In addition, observers agreed that the parenchymal structure of the upper abdominal solid organs and the anatomic details of the stomach wall structure were better with BLADE (Gwet's AC2 = 0.87). In most cases, both observers preferred BLADE (p <0.0001) for evaluating images and lesion morphology.
Conclusion: In upper abdominal MRI examination, artifacts, especially movement artifacts, were significantly reduced by BLADE, yielding more valuable data for the evaluation of the gastrointestinal system wall structure and its pathologies, especially considering the organs near to the diaphragm and retroperitoneal organs as well as vascular structures.
... Previous studies utilizing PROPELLER imaging in the pelvis are limited, but its use has been shown to be effective in diminishing motion correction in anatomical regions outside of the prostate, including the male and female pelvis [16,20]. A similar feasibility study performed by Deng et al. in the abdomen was able to show that PRO-PELLER-DWI acquisition improved image quality, decreased artefact and reduced geometric distortion, but study was based on a small patient group, and partly on phantoms [10]. ...
... Pelvic imaging in these patients is often non-diagnostic in current clinical practice using EP-DWI, whilst the use of PROPEL-LER-DWI has been shown to increase image quality and decrease artefact and distortion. As noted in previous studies by Froehlich et al. and Rosenkrantz et al. this may be of importance for tumour diagnosis, as previous studies have shown a significant decrease in contrast [20]. In this study, we did not assess lesion conspicuity but this could be examined in future work. ...
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 tesla 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 9.2ng/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.
... Previous studies utilizing PROPELLER imaging in the pelvis are limited, but its use has been shown to be effective in diminishing motion correction in anatomical regions outside of the prostate, including the male and female pelvis [16,20]. A similar feasibility study performed by Deng et al. in the abdomen was able to show that PRO-PELLER-DWI acquisition improved image quality, decreased artefact and reduced geometric distortion, but study was based on a small patient group, and partly on phantoms [10]. ...
... Pelvic imaging in these patients is often non-diagnostic in current clinical practice using EP-DWI, whilst the use of PROPEL-LER-DWI has been shown to increase image quality and decrease artefact and distortion. As noted in previous studies by Froehlich et al. and Rosenkrantz et al. this may be of importance for tumour diagnosis, as previous studies have shown a significant decrease in contrast [20]. In this study, we did not assess lesion conspicuity but this could be examined in future work. ...
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.
... The Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction (PROPELLER) technique was first presented by Pipe et al. in 1999 as a new method to reduce motion artefacts in magnetic resonance imaging (MRI) of the brain and the heart using radial k-space sampling [1]. In the past 15 years, several studies have confirmed this improvement for different body regions, e.g. the brain, neck, thorax, abdomen, and pelvis [2][3][4][5][6][7][8][9]. In 2014, Pipe et al. advanced the PROPELLER technique to further reduce noise and artefacts allowing for very robust motion corrected images [10]; this revised PROPELLER technique is called MultiVane XD (MVXD, Philips Healthcare, Best, The Netherlands). ...
... Furthermore, the signal-to-noise ratio can be increased because of the redundancy in data sampling [1][2][3][4]10]. Advanced methods of radial kspace sampling have been shown to reduce motion artefacts in different body regions [1][2][3][4][5][6][7][8][9]. ...
... The drawback of a lower T2-contrast has also been described in studies on T2-weighted imaging (T2WI) of the pelvis, both using a PROPELLER equivalent [8,9]. According to an experimental preclinical study, the lower T2-contrast of MR sequences using radial sampling might be explained by a non-uniform weighting of k-space data in the phase-encode direction [18]. ...
Purpose:
To evaluate revised PROPELLER (RevPROP) for T2-weighted imaging (T2WI) of the prostate as a substitute for turbo spin echo (TSE).
Materials and methods:
Three-Tesla MR images of 50 patients with 55 cancer-suspicious lesions were prospectively evaluated. Findings were correlated with histopathology after MRI-guided biopsy. T2 RevPROP, T2 TSE, diffusion-weighted imaging, dynamic contrast enhancement, and MR-spectroscopy were acquired. RevPROP was compared to TSE concerning PI-RADS scores, lesion size, lesion signal-intensity, lesion contrast, artefacts, and image quality.
Results:
There were 41 carcinomas in 55 cancer-suspicious lesions. RevPROP detected 41 of 41 carcinomas (100%) and 54 of 55 lesions (98.2%). TSE detected 39 of 41 carcinomas (95.1%) and 51 of 55 lesions (92.7%). RevPROP showed fewer artefacts and higher image quality (each p < 0.001). No differences were observed between single and overall PI-RADS scores based on RevPROP or TSE (p = 0.106 and p = 0.107). Lesion size was not different (p = 0.105). T2-signal intensity of lesions was higher and T2-contrast of lesions was lower on RevPROP (each p < 0.001).
Conclusion:
For prostate cancer detection RevPROP is superior to TSE with respect to motion robustness, image quality and detection rates of lesions. Therefore, RevPROP might be used as a substitute for T2WI.
Key points:
• Revised PROPELLER can be used as a substitute for T2-weighted prostate imaging. • Revised PROPELLER detected more carcinomas and more suspicious lesions than TSE. • Revised PROPELLER showed fewer artefacts and better image quality compared to TSE. • There were no significant differences in PI-RADS scores between revised PROPELLER and TSE. • The lower T2-contrast of revised PROPELLER did not impair its diagnostic quality.
... To our knowledge, there is only one study which reports on the application of BLADE in breast MRI (17) . Prior studies evaluating BLADE in non-breast applications have reported a reduction of motion artifacts and improvement in qualitative analysis of T2-weighted sequences (8)(9)(10)(11)(13)(14)(15)(16)(17) . ...
Objective:
The purpose of this study was to compare two short-tau inversion recovery (STIR) sequences, Cartesian and radial (BLADE) acquisitions, for breast magnetic resonance imaging (MRI) examinations.
Materials and Methods:
Ninety-six women underwent 1.5 T breast MRI exam (48 Cartesian and 48 BLADE). Qualitative analysis including image artifacts, image quality, fat-suppression, chest-wall depiction, lesion detection, lymph node depiction and overall impression were evaluated by three blinded readers. Signal to noise ratios (SNRs) were calculated. Cronbach's alpha test was used to assess inter-observer agreement. Subanalyses of image quality, chest-wall depiction and overall impression in 15 patients with implants and image quality in 31 patients with clips were correlated using Pearson test. Wilcoxon rank sum test and t-test were performed.
Results:
Motion artifacts were present in 100% and in 0% of the Cartesian and the BLADE exams, respectively. Chemical-shift artifacts were present in 8% of the Cartesian exams. Flow artifacts were more frequent on BLADE. BLADE sequence was statistically superior to Cartesian for all qualitative features (p < 0.05) except for fat-suppression (p = 0.054). In the subanalysis, BLADE was superior for implants and clips (p < 0.05). SNR was statistically greater for BLADE (48.35 vs. 16.17). Cronbach ranged from 0.502 to 0.813.
Conclusion:
BLADE appears to be superior to Cartesian acquisition of STIR imaging as measured by improved image quality, fewer artifacts, and improved chest wall and lymph node depiction.
... www.impactjournals.com/oncotarget [67,68]. Recent technological developments in MRI, including new sequences (echo-planar imaging sequence, multichannel coils and parallel imaging), the high-field magnet and volumetric acquisition of T1-weighted images, allow the acquisition of DWI that is largely free of motion artifacts and provide excellent anatomical detail [23,69,70]. ...
The diagnostic values of diffusion weighted imaging (DWI) and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) for N-staging of gastric cancer (GC) were identified and compared. After a systematic search to identify relevant articles, meta-analysis was used to summarize the sensitivities, specificities, and areas under curves (AUCs) for DWI and PET/CT. To better understand the diagnostic utility of DWI and PET/CT for N-staging, the performance of multi-detector computed tomography (MDCT) was used as a reference. Fifteen studies were analyzed. The pooled sensitivity, specificity, and AUC with 95% confidence intervals of DWI were 0.79 (0.73–0.85), 0.69 (0.61–0.77), and 0.81 (0.77–0.84), respectively. For PET/CT, the corresponding values were 0.52 (0.39–0.64), 0.88 (0.61–0.97), and 0.66 (0.62–0.70), respectively. Comparison of the two techniques revealed DWI had higher sensitivity and AUC, but no difference in specificity. DWI exhibited higher sensitivity but lower specificity than MDCT, and ¹⁸F-FDG PET/CT had lower sensitivity and equivalent specificity. Overall, DWI performed better than ¹⁸F-FDG PET/CT for preoperative N-staging in GC. When the efficacy of MDCT was taken as a reference, DWI represented a complementary imaging technique, while ¹⁸F-FDG PET/CT had limited utility for preoperative N-staging.
... T2W imaging is typically performed using turbo/fast spin-echo techniques [39]. Motion correction with radial acquisition (BLADE, Siemens Healthcare, Malvern, PA, USA; PROPELLER, General Electric Healthcare, Milwaukee, WI, USA) sequences are popular for pelvic imaging because they correct for in-plane rotation and translational artefacts and have been shown to result in improved overall image quality when compared to conventional spin echo [59,60]. A disadvantage of these sequences is decreased image contrast compared to conventional spin echo [59]. ...
... Motion correction with radial acquisition (BLADE, Siemens Healthcare, Malvern, PA, USA; PROPELLER, General Electric Healthcare, Milwaukee, WI, USA) sequences are popular for pelvic imaging because they correct for in-plane rotation and translational artefacts and have been shown to result in improved overall image quality when compared to conventional spin echo [59,60]. A disadvantage of these sequences is decreased image contrast compared to conventional spin echo [59]. Recently, Rosenkrantz et al. demonstrated that a minority of PCa foci may be obscured at T2W MRI when BLADE/PROPELLER is used compared to conventional spin echo [61] (Fig. 12). ...
MP-MRI is a critical component in active surveillance (AS) of prostate cancer (PCa) because of a high negative predictive value for clinically significant tumours. This review illustrates pitfalls of MP-MRI and how to recognise and avoid them. The anterior fibromuscular stroma and central zone are low signal on T2W-MRI/apparent diffusion coefficient (ADC), resembling PCa. Location, progressive enhancement and low signal on b ≥1000 mm²/s echo-planar images (EPI) are differentiating features. BPH can mimic PCa. Glandular BPH shows increased T2W/ADC signal, cystic change and progressive enhancement; however, stromal BPH resembles transition zone (TZ) PCa. A rounded morphology, low T2 signal capsule and posterior/superior location favour stromal BPH. Acute/chronic prostatitis mimics PCa at MP-MRI, with differentiation mainly on clinical grounds. Visual analysis of diffusion-weighted MRI must include EPI and appropriate windowing of ADC. Quantitative ADC analysis is limited by lack of standardization; the ADC ratio and ADC histogram analysis are alternatives to mean values. DCE lacks standardisation and has limited utility in the TZ, where T2W/DWI are favoured. Targeted TRUS-guided biopsies of MR-detected lesions are challenging. Lesions detected on MP-MRI may not be perfectly targeted with TRUS and this must be considered when faced with a suspicious lesion on MP-MRI and a negative targeted TRUS biopsy histopathological result.
• Multi-parametric MRI plays a critical role in prostate cancer active surveillance. • Low T2W signal intensity structures appear dark on ADC, potentially simulating cancer. • Stromal BPH mimics cancer at DWI and DCE. • Long b value trace EPI should be reviewed • Targeted biopsy of MR-detected lesions using TRUS guidance may be challenging.
