The Transatlantic Recommendations for Prostate Gland Evaluation with Magnetic Resonance Imaging After Focal Therapy (TARGET): A Systematic Review and International Consensus Recommendations.

BACKGROUND AND OBJECTIVE: Magnetic resonance imaging (MRI) can detect recurrences after focal therapy for prostate cancer but there is no robust guidance regarding its use. Our objective was to produce consensus recommendations on MRI acquisition, interpretation, and reporting after focal therapy. METHODS: A systematic review was performed in July 2022 to develop consensus statements. A two-round consensus exercise was then performed, with a consensus meeting in January 2023, during which 329 statements were scored by 23 panellists from Europe and North America spanning urology, radiology, and pathology with experience across eight focal therapy modalities. Using RAND Corporation/University of California-Los Angeles methodology, the Transatlantic Recommendations for Prostate Gland Evaluation with MRI after Focal Therapy (TARGET) were based on consensus for statements scored with agreement or disagreement. KEY FINDINGS AND LIMITATIONS: In total, 73 studies were included in the review. All 20 studies (100%) reporting suspicious imaging features cited focal contrast enhancement as suspicious for cancer recurrence. Of 31 studies reporting MRI assessment criteria, the Prostate Imaging-Reporting and Data System (PI-RADS) score was the scheme used most often (20 studies; 65%), followed by a 5-point Likert score (six studies; 19%). For the consensus exercise, consensus for statements scored with agreement or disagreement increased from 227 of 295 statements (76.9%) in round one to 270 of 329 statements (82.1%) in round two. Key recommendations include performing routine MRI at 12 mo using a multiparametric protocol compliant with PI-RADS version 2.1 standards. PI-RADS category scores for assessing recurrence within the ablation zone should be avoided. An alternative 5-point scoring system is presented that includes a major dynamic contrast enhancement (DCE) sequence and joint minor diffusion-weighted imaging and T2-weighted sequences. For the DCE sequence, focal nodular strong early enhancement was the most suspicious imaging finding. A structured minimum reporting data set and minimum reporting standards for studies detailing MRI data after focal therapy are presented. CONCLUSIONS AND CLINICAL IMPLICATIONS: The TARGET consensus recommendations may improve MRI acquisition, interpretation, and reporting after focal therapy for prostate cancer and provide minimum standards for study reporting. PATIENT SUMMARY: Magnetic resonance imaging (MRI) scans can detect recurrent of prostate cancer after focal treatments, but there is a lack of guidance on MRI use for this purpose. We report new expert recommendations that may improve practice.

Severe emphysematous pyelonephritis as a complication of klebsiella pneumonia and uncontrolled diabetes mellitus.

A female in her 40s, with poorly controlled Type I diabetes mellitus, was brought to our tertiary hospital by ambulance after being found drowsy. Six days prior, she had self-discharged from the Intensive Care Unit whilst being treated for a Klebsiella pneumonia. At re-admission, she had an acute kidney injury with abdominal pain and clinical features of sepsis. Her presentation was attributed to ongoing Klebsiella pneumoniae infection; however, a chest radiograph showed marked improvement of pulmonary consolidations and an unusual subdiaphragmatic gas pattern. A CT scan demonstrated severe bilateral emphysematous pyelonephritis. The patient was unfit for bilateral nephrectomy and was medically managed in the Intensive Care Unit for 41 days, before transfer to a specialist renal unit for life-long haemodialysis. This case highlights the importance of considering emphysematous pyelonephritis in patients presenting with uncontrolled diabetes mellitus and acute kidney injury and/or infection, the role of imaging in its diagnosis, and the challenges of complex social circumstances in health management.

Magnetic Resonance Imaging Follow-up of Targeted Biopsy-negative Prostate Lesions.

BACKGROUND: The optimal radiological follow-up of prostate lesions negative on magnetic resonance imaging (MRI)-targeted biopsy (MRI-TB) is yet to be optimised. OBJECTIVE: To present medium-term radiological and clinical follow-up of biopsy-negative lesions. DESIGN, SETTING, AND PARTICIPANTS: The records for men who underwent multiparametric MRI at the UCLH one-stop clinic for suspected prostate cancer between September 2017 and March 2020 were reviewed (n = 1199). Patients with Likert 4 or 5 lesions were considered (n = 495), and those with a subsequent negative MRI-TB comprised the final study population (n = 91). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Baseline and follow-up MRI and biopsy data (including prostate-specific antigen [PSA], prostate volume, radiological scores, and presence of any noncancerous pathology) were extracted from reports. The last follow-up date was the date of the last test or review in clinic. RESULTS AND LIMITATIONS: Median follow-up was 1.8 yr (656 d, interquartile range [IQR] 359-1008). At baseline, the median age was 65.4 yr (IQR 60.7-70.0), median PSA was 7.1 ng/ml (IQR 4.7-10.0), median prostate volume was 54 ml (IQR 39.5-75.0), and median PSA density (PSAD) was 0.13 ng/ml2 (IQR 0.09-0.18). Eighty-six men (95%) had Likert 4 lesions, while the remaining five (5%) had Likert 5 lesions. Only 21 men (23%) had a single lesion; most had at least two. Atrophy was the most prevalent pathology on MRI-TB, present in 64 men (74%), and followed by acute inflammation in 42 (46%), prostatic intraepithelial neoplasia in 33 (36%), chronic inflammation in 18 (20%), atypia in 13 (14%), and granulomatous inflammation in three (3%). Fifty-eight men had a second MRI study (median 376 d, IQR 361-412). At the second MRI, median PSAD decreased to 0.11 ng/ml2 (IQR 0.08-0.18). A Likert 4 or 5 score persisted only in five men (9%); 40 men (69%) were scored Likert 3, while the remaining 13 (22%) were scored Likert 2 (no lesion). Of 45 men with a Likert ≥3 score, most only had one lesion at the second MRI (28 men; 62%). Of six men with repeat MRI-TB during the study period, two were subsequently diagnosed with prostate cancer and both had persistent Likert 4 scores (at baseline and at least one follow-up MRI). CONCLUSIONS: Most biopsy-negative MRI lesions in the prostate resolve over time, but any persistent lesions should be closely monitored. PATIENT SUMMARY: Lesions in the prostate detected via magnetic resonance imaging (MRI) scans that are negative for cancer on biopsy usually resolve. Repeat MRI can indicate persistent lesions that might need a second biopsy.

MRI in the Management of Prostate Cancer.

Multiparametric MRI has a changing role in prostate cancer diagnosis. Internationally recognized consensus documents such as prostate imaging reporting and data system version have been developed and adapted to standardize the acquisition and reporting of prostate MRI. The improvement in scanning techniques and development of highly sensitive functional sequences have improved the detection of clinically significant prostate cancer as well as treatment planning and follow up. This has led to a recent NICE recommendation to use prostate MRI as the initial investigation in men with clinically suspected localized disease. The results of several recent international MRI prostate trials are influencing the way imaging is used to stratify which patients require a prostate biopsy as well as how MRI guidance is used to target biopsies.

Comparison of MRI Activity Scoring Systems and Features for the Terminal Ileum in Patients With Crohn Disease.

OBJECTIVE: The purpose of this study was to evaluate four previously validated MRI activity scoring systems for diagnosis and grading of Crohn disease (CD) in the terminal ileum against an endoscopic and histopathologic reference standard. SUBJECTS AND METHODS: Ethics approval and written informed consent were obtained. Subjects with known or suspected CD were prospectively recruited between December 2011 and August 2014. Each patient underwent MRI and ileocolonoscopy with terminal ileum biopsies. Four MRI scoring systems (Magnetic Resonance Index of Activity [MaRIA], Clermont score, London score, and Crohn disease MRI Index) and component features were applied by two observers and correlated to the Crohn disease endoscopic index of severity (CDEIS, 0-44) and histopathologic endoscopic acute inflammation score (0-6). Interobserver agreement (weighted kappa and intraclass correlation coefficient [ICC]) and diagnostic accuracy for active and ulcerating endoscopic or histopathologic disease were evaluated. RESULTS: Ninety-eight patients (median age, 32 years old; 55 women, 43 men) were included. All four scoring systems showed good interobserver agreement (ICC = 0.70-0.78), moderate-to-strong correlation to CDEIS (r = 0.57-0.67) and weak-to-moderate correlation to endoscopic acute inflammation score (r = 0.38-0.49). Scoring systems' diagnostic accuracy for active and ulcerating endoscopic disease ranged from 73% to 78% and 71% to 76%, respectively, whereas for active histopathologic disease accuracy ranged from 65% to 72%. Between the scoring systems, no significant differences were found for both observers regarding interobserver agreement, correlation coefficients, and diagnostic accuracy. CONCLUSION: All scoring systems were comparable in terms of interobserver agreement, correlation to the endoscopic and histopathologic reference standard, and diagnostic accuracy. The London score, MaRIA, and Clermont score have the additional benefit of having validated cutoff values for both active and ulcerating endoscopic disease.

Arterial spin labelling MRI to measure renal perfusion: a systematic review and statement paper.

Renal perfusion provides the driving pressure for glomerular filtration and delivers the oxygen and nutrients to fuel solute reabsorption. Renal ischaemia is a major mechanism in acute kidney injury and may promote the progression of chronic kidney disease. Thus, quantifying renal tissue perfusion is critically important for both clinicians and physiologists. Current reference techniques for assessing renal tissue perfusion have significant limitations. Arterial spin labelling (ASL) is a magnetic resonance imaging (MRI) technique that uses magnetic labelling of water in arterial blood as an endogenous tracer to generate maps of absolute regional perfusion without requiring exogenous contrast. The technique holds enormous potential for clinical use but remains restricted to research settings. This statement paper from the PARENCHIMA network briefly outlines the ASL technique and reviews renal perfusion data in 53 studies published in English through January 2018. Renal perfusion by ASL has been validated against reference methods and has good reproducibility. Renal perfusion by ASL reduces with age and excretory function. Technical advancements mean that a renal ASL study can acquire a whole kidney perfusion measurement in less than 5-10 min. The short acquisition time permits combination with other MRI techniques that might inform drug mechanisms and renal physiology. The flexibility of renal ASL has yielded several variants of the technique, but there are limited data comparing these approaches. We make recommendations for acquiring and reporting renal ASL data and outline the knowledge gaps that future research should address.

Semiautomatic Assessment of the Terminal Ileum and Colon in Patients with Crohn Disease Using MRI (the VIGOR++ Project).

RATIONALE AND OBJECTIVES: The objective of this study was to develop and validate a predictive magnetic resonance imaging (MRI) activity score for ileocolonic Crohn disease activity based on both subjective and semiautomatic MRI features. MATERIALS AND METHODS: An MRI activity score (the "virtual gastrointestinal tract [VIGOR]" score) was developed from 27 validated magnetic resonance enterography datasets, including subjective radiologist observation of mural T2 signal and semiautomatic measurements of bowel wall thickness, excess volume, and dynamic contrast enhancement (initial slope of increase). A second subjective score was developed based on only radiologist observations. For validation, two observers applied both scores and three existing scores to a prospective dataset of 106 patients (59 women, median age 33) with known Crohn disease, using the endoscopic Crohn's Disease Endoscopic Index of Severity (CDEIS) as a reference standard. RESULTS: The VIGOR score (17.1 × initial slope of increase + 0.2 × excess volume + 2.3 × mural T2) and other activity scores all had comparable correlation to the CDEIS scores (observer 1: r = 0.58 and 0.59, and observer 2: r = 0.34-0.40 and 0.43-0.51, respectively). The VIGOR score, however, improved interobserver agreement compared to the other activity scores (intraclass correlation coefficient = 0.81 vs 0.44-0.59). A diagnostic accuracy of 80%-81% was seen for the VIGOR score, similar to the other scores. CONCLUSIONS: The VIGOR score achieves comparable accuracy to conventional MRI activity scores, but with significantly improved reproducibility, favoring its use for disease monitoring and therapy evaluation.

Investigating Low-Velocity Fluid Flow in Tumors with Convection-MRI.

Several distinct fluid flow phenomena occur in solid tumors, including intravascular blood flow and interstitial convection. Interstitial fluid pressure is often raised in solid tumors, which can limit drug delivery. To probe low-velocity flow in tumors resulting from raised interstitial fluid pressure, we developed a novel MRI technique named convection-MRI, which uses a phase-contrast acquisition with a dual-inversion vascular nulling preparation to separate intra- and extravascular flow. Here, we report the results of experiments in flow phantoms, numerical simulations, and tumor xenograft models to investigate the technical feasibility of convection-MRI. We observed a significant correlation between estimates of effective fluid pressure from convection-MRI with gold-standard, invasive measurements of interstitial fluid pressure in mouse models of human colorectal carcinoma. Our results show how convection-MRI can provide insights into the growth and responsiveness to vascular-targeting therapy in colorectal cancers.Significance: A noninvasive method for measuring low-velocity fluid flow caused by raised fluid pressure can be used to assess changes caused by therapy. Cancer Res; 78(7); 1859-72. ©2018 AACR.

Lymphoid nodular hyperplasia of the terminal ileum can mimic active crohn disease on MR enterography.

OBJECTIVE: The purpose of this article is to describe the MRI findings associated with lymphoid nodular hyperplasia at MR enterography and test the ability of radiologists to differentiate healthy control subjects from patients with Crohn disease (CD). MATERIALS AND METHODS: Ethical approval was granted for this retrospective study. Thirty-five subjects (nine with lymphoid nodular hyperplasia, 13 with CD, and 13 control subjects) who had undergone MR enterography and ileocolonoscopy were identified from the hospital database. Two abdominal radiologists, working in consensus and blinded to diagnosis, scored enteric MR images for T2 signal, contrast enhancement, mural thickness, and diffusion-weighted imaging (DWI) signal and measured the apparent diffusion coefficient (ADC) in all three groups. Scores were compared using the Kruskal-Wallis test. RESULTS: T2 signal and contrast enhancement were judged subjectively to be greater in patients with lymphoid nodular hyperplasia and CD than control subjects (p < 0.001). Mural thickness was greater for patients with lymphoid nodular hyperplasia (median, 6.0 mm) and CD (median, 7.3 mm) than control subjects (median, 2.3 mm) (p < 0.001). Lymphoid nodular hyperplasia and CD increased subjective DWI signal and reduced ADC in comparison with normal control subjects; median ADC was 1.34 × 10(-3) mm(2)/s for lymphoid nodular hyperplasia, 1.36 × 10(-3) mm(2)/s for CD, and 1.86 × 10(-3) mm(2)/s for control subjects (p < 0.001). None of T2 signal, contrast enhancement, wall thickness, DWI signal, or ADC value significantly differed between lymphoid nodular hyperplasia and CD. Lymphoid nodular hyperplasia was erroneously diagnosed as CD in blinded assessment in four of nine cases (44%), whereas all cases of CD and healthy control subjects were correctly classified. CONCLUSION: Lymphoid nodular hyperplasia alters both subjective and quantitative MRI parameters, including T2 signal, contrast enhancement, mural thickness, and ADC. In a subset of patients, lymphoid nodular hyperplasia may be indistinguishable from CD on MR enterography.

Sensitivity and specificity of CT colonography for the detection of colonic neoplasia after positive faecal occult blood testing: systematic review and meta-analysis.

OBJECTIVE: CT colonography (CTC) is recommended after positive faecal occult blood testing (FOBt) when colonoscopy is incomplete or infeasible. We aimed to estimate the sensitivity and specificity of CTC for colorectal cancer and adenomatous polyps following positive FOBt via systematic review. METHODS: The MEDLINE, EMBASE, AMED and Cochrane Library databases were searched for CTC studies reporting sensitivity and specificity for colorectal cancer and adenomatous polyps. Included subjects had tested FOBt-positive by guaiac or immunochemical methods. Per-patient detection rates were summarized via forest plots. Meta-analysis of sensitivity and specificity was conducted using a bivariate random effects model and the average operating point calculated. RESULTS: Of 538 articles considered, 5 met inclusion criteria, describing results from 622 patients. Research study quality was good. CTC had a high per-patient average sensitivity of 88.8 % (95 % CI 83.6 to 92.5 %) for ≥6 mm adenomas or colorectal cancer, with low between-study heterogeneity. Specificity was both more heterogeneous and lower, at an average of 75.4 % (95 % CI 58.6 to 86.8 %). CONCLUSION: Few studies have investigated CTC in FOBt-positive individuals. CTC is sensitive at a ≥6 mm threshold but specificity is lower and variable. Despite the limited data, these results suggest that CTC may adequately substitute for colonoscopy when the latter is undesirable. KEY POINTS: • FOBt is the most common mass screening test for colorectal cancer. • Few studies evaluate CT colonography after positive FOBt. • CTC is approximately 89 % sensitive for ≥6 mm adenomas/cancer in this setting. • Specificity is lower, at approximately 75 %, and more variable. • CT colonography is a good alternative when colonoscopy is undesirable.