Ultra-low-dose CT versus chest X-ray for patients suspected of pulmonary disease at the emergency department: a multicentre randomised clinical trial.

BACKGROUND: Chest CT displays chest pathology better than chest X-ray (CXR). We evaluated the effects on health outcomes of replacing CXR by ultra-low-dose chest-CT (ULDCT) in the diagnostic work-up of patients suspected of non-traumatic pulmonary disease at the emergency department. METHODS: Pragmatic, multicentre, non-inferiority randomised clinical trial in patients suspected of non-traumatic pulmonary disease at the emergency department. Between 31 January 2017 and 31 May 2018, every month, participating centres were randomly allocated to using ULDCT or CXR. Primary outcome was functional health at 28 days, measured by the Short Form (SF)-12 physical component summary scale score (PCS score), non-inferiority margin was set at 1 point. Secondary outcomes included hospital admission, hospital length of stay (LOS) and patients in follow-up because of incidental findings. RESULTS: 2418 consecutive patients (ULDCT: 1208 and CXR: 1210) were included. Mean SF-12 PCS score at 28 days was 37.0 for ULDCT and 35.9 for CXR (difference 1.1; 95% lower CI: 0.003). After ULDCT, 638/1208 (52.7%) patients were admitted (median LOS of 4.8 days; IQR 2.1-8.8) compared with 659/1210 (54.5%) patients after CXR (median LOS 4.6 days; IQR 2.1-8.8). More ULDCT patients were in follow-up because of incidental findings: 26 (2.2%) versus 4 (0.3%). CONCLUSIONS: Short-term functional health was comparable between ULDCT and CXR, as were hospital admissions and LOS, but more incidental findings were found in the ULDCT group. Our trial does not support routine use of ULDCT in the work-up of patients suspected of non-traumatic pulmonary disease at the emergency department. TRIAL REGISTRATION NUMBER: NTR6163.

The yield of chest X-ray or ultra-low-dose chest-CT in emergency department patients suspected of pulmonary infection without respiratory symptoms or signs.

OBJECTIVE: The yield of pulmonary imaging in patients with suspected infection but no respiratory symptoms or signs is probably limited, ultra-low-dose CT (ULDCT) is known to have a higher sensitivity than Chest X-ray (CXR). Our objective was to describe the yield of ULDCT and CXR in patients clinically suspected of infection, but without respiratory symptoms or signs, and to compare the diagnostic accuracy of ULDCT and CXR. METHODS: In the OPTIMACT trial, patients suspected of non-traumatic pulmonary disease at the emergency department (ED) were randomly allocated to undergo CXR (1210 patients) or ULDCT (1208 patients). We identified 227 patients in the study group with fever, hypothermia, and/or elevated C-reactive protein (CRP) but no respiratory symptoms or signs, and estimated ULDCT and CXR sensitivity and specificity in detecting pneumonia. The final day-28 diagnosis served as the clinical reference standard. RESULTS: In the ULDCT group, 14/116 (12%) received a final diagnosis of pneumonia, versus 8/111 (7%) in the CXR group. ULDCT sensitivity was significantly higher than that of CXR: 13/14 (93%) versus 4/8 (50%), a difference of 43% (95% CI: 6 to 80%). ULDCT specificity was 91/102 (89%) versus 97/103 (94%) for CXR, a difference of - 5% (95% CI: - 12 to 3%). PPV was 54% (13/24) for ULDCT versus 40% (4/10) for CXR, NPV 99% (91/92) versus 96% (97/101). CONCLUSION: Pneumonia can be present in ED patients without respiratory symptoms or signs who have a fever, hypothermia, and/or elevated CRP. ULDCT's sensitivity is a significant advantage over CXR when pneumonia has to be excluded. CLINICAL RELEVANCE STATEMENT: Pulmonary imaging in patients with suspected infection but no respiratory symptoms or signs can result in the detection of clinically significant pneumonia. The increased sensitivity of ultra-low-dose chest CT compared to CXR is of added value in vulnerable and immunocompromised patients. KEY POINTS: • Clinical significant pneumonia does occur in patients who have a fever, low core body temperature, or elevated CRP without respiratory symptoms or signs. • Pulmonary imaging should be considered in patients with unexplained symptoms or signs of infections. • To exclude pneumonia in this patient group, ULDCT's improved sensitivity is a significant advantage over CXR.

[18F]FDG-PET or PET/CT in the evaluation of pelvic and para-aortic lymph nodes in patients with locally advanced cervical cancer: A systematic review of the literature.

PURPOSE: Imaging is essential in detecting lymph node metastases for radiotherapy treatment planning in locally advanced cervical cancer (LACC). There are not many data on the performance of [18F]FDG-PET(CT) in showing lymph node metastases in LACC. We pooled sensitivity and specificity of [18F]FDG-PET(CT) for detecting pelvic and/or para-aortic lymph node metastases in patients with LACC. Also, the positive and negative posttest probabilities at high and low levels of prevalence were determined. METHODS: MEDLINE and EMBASE searches were performed and quality characteristics assessed. Logit-sensitivity and logit-specificity estimates with corresponding standard errors were calculated. Summary estimates of sensitivity and specificity with corresponding 95% confidence intervals (CIs) were calculated by anti-logit transformation. Positive and negative likelihood ratios (LRs) were calculated from the mean logit-sensitivity and mean logit-specificity and the corresponding standard errors. The posttest probabilities were determined by Bayesian approach. RESULTS: Twelve studies were included with a total of 778 patients aged 10-85 years. For pelvic nodes, summary estimates of sensitivity, specificity, LR+ and LR- were: 0.88 (95%CI: 0.40-0.99), 0.93 (95%CI: 0.85-0.97), 11.90 (95%CI: 5.32-26.62) and 0.13 (95%CI: 0.01-1.08). At the lowest prevalence of 0.15 the positive predictive value (PPV) and negative predictive value (NPV) were 0.68 and 0.98, at the highest prevalence of 0.65, 0.96 and 0.81. For the para-aortic nodes, the summary estimates of sensitivity, specificity LR+ and LR- were: 0.40 (95%CI: 0.18-0.66), 0.93 (95%CI: 0.91-0.95), 6.08 (95%CI: 2.90-12.78) and 0.64 (95%CI: 0.42-0.99), respectively. At the lowest prevalence of 0.17 the PPV and NPV were 0.55 and 0.88, at the highest prevalence of 0.50, 0.86 and 0.61. CONCLUSION: The PPV and NPV of [18F]FDG-PET(CT) showing lymph node metastases in patients with LACC improves with higher prevalence. Prevalence and predictive values should be taken into account when determining therapeutic strategies based on [18F]FDG-PET(CT).

The Prevalence of Sexual Abuse in Adolescence in Suriname.

Studies conducted to ascertain the prevalence of child sexual abuse (CSA) in the Caribbean are poorly synthesized. Present study reports on the lifetime and year prevalence of unwanted sexual experiences, the risk of CSA at different ages within adolescence, and differences between the three largest ethnic groups in Suriname. One thousand one hundred and twenty (1,120) adolescents completed a questionnaire on child maltreatment, including CSA. The study's stratified sample consisted of students (ages 12 to 17) from five districts in Suriname. More than 16% of all boys and 15% of all girls indicated that they had been exposed to some form of CSA in the past 12 months. Girls reported significantly more intrafamilial CSA by a minor than boys. Boys reported significantly more experiences of being touched or forced by a minor outside the family to look at/touch the abuser's private parts than girls. Besides, 16 and 17-year olds were the most vulnerable. An increased risk of CSA (year prevalence) was found as adolescence progresses. A significant portion of CSA constituted peer-to-peer sexual victimization. Afro Surinamese adolescents were found to report the highest rates of CSA. Appropriate legislation, policies, and services for prevention and recovery are needed in Suriname.

Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting.

OBJECTIVES: To update the 2012 ESGAR consensus guidelines on the acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for clinical staging and restaging of rectal cancer. METHODS: Fourteen abdominal imaging experts from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) participated in a consensus meeting, organised according to an adaptation of the RAND-UCLA Appropriateness Method. Two independent (non-voting) Chairs facilitated the meeting. 246 items were scored (comprising 229 items from the previous 2012 consensus and 17 additional items) and classified as 'appropriate' or 'inappropriate' (defined by ≥ 80 % consensus) or uncertain (defined by < 80 % consensus). RESULTS: Consensus was reached for 226 (92 %) of items. From these recommendations regarding hardware, patient preparation, imaging sequences and acquisition, criteria for MR imaging evaluation and reporting structure were constructed. The main additions to the 2012 consensus include recommendations regarding use of diffusion-weighted imaging, criteria for nodal staging and a recommended structured report template. CONCLUSIONS: These updated expert consensus recommendations should be used as clinical guidelines for primary staging and restaging of rectal cancer using MRI. KEY POINTS: • These guidelines present recommendations for staging and reporting of rectal cancer. • The guidelines were constructed through consensus amongst 14 pelvic imaging experts. • Consensus was reached by the experts for 92 % of the 246 items discussed. • Practical guidelines for nodal staging are proposed. • A structured reporting template is presented.

Correction to: Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting.

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Contrast-enhanced CT in determining resectability in patients with pancreatic carcinoma: a meta-analysis of the positive predictive values of CT.

OBJECTIVE: To obtain a summary positive predictive value (sPPV) of contrast-enhanced CT in determining resectability. METHODS: The MEDLINE and EMBASE databases from JAN2005 to DEC2015 were searched and checked for inclusion criteria. Data on study design, patient characteristics, imaging techniques, image evaluation, reference standard, time interval between CT and reference standard, and data on resectability/unresectablity were extracted by two reviewers. We used a fixed-effects or random-effects approach to obtain sPPV for resectability. Several subgroups were defined: 1) bolus-triggering versus fixed-timing; 2) pancreatic and portal phases versus portal phase alone; 3) all criteria (liver metastases/lymphnode involvement/local advanced/vascular invasion) versus only vascular invasion as criteria for unresectability. RESULTS: Twenty-nine articles were included (2171 patients). Most studies were performed in multicentre settings, initiated by the department of radiology and retrospectively performed. The I2-value was 68%, indicating heterogeneity of data. The sPPV was 81% (95%CI: 75-86%). False positives were mostly liver, peritoneal, or lymphnode metastases. Bolus-triggering had a slightly higher sPPV compared to fixed-timing, 87% (95%CI: 81-91%) versus 78% (95%CI: 66-86%) (p = 0.077). No differences were observed in other subgroups. CONCLUSIONS: This meta-analysis showed a sPPV of 81% for predicting resectability by CT, meaning that 19% of patients falsely undergo surgical exploration. KEY POINTS: • Predicting resectability of pancreatic cancer by CT is 81% (95%CI: 75-86%). • The percentage of patients falsely undergoing surgical exploration is 19%. • The false positives are liver metastases, peritoneal metastases, or lymph node metastases.

Prediction of presence of kidney disease in patients undergoing intravenous iodinated contrast enhanced computed tomography: a validation study.

OBJECTIVES: To validate two previously presented models containing risk factors to identify patients with estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2 or eGFR <45 ml/min/1.73 m2. METHODS: In random patients undergoing intravenous contrast-enhanced computed tomography (CECT) the following risk factors were assessed: history of urological/nephrological disease, hypertension, diabetes mellitus, anaemia, congestive heart failure, other cardiovascular disease or multiple myeloma or Waldenström disease. Data on kidney function, age, gender and type and indication of CECT were also registered. We studied two models: model A-diabetes mellitus, history of urological/nephrological disease, cardiovascular disease, hypertension; model B-diabetes mellitus, history of urological/nephrological disease, age >75 years and congestive heart failure. For each model, associations with eGFR <60 ml/min/1.73 m2 or eGFR <45 ml/min/1.73 m2 was studied. RESULTS: A total of 1,001 patients, mean age 60.36 years were included. In total, 92 (9.2 %) patients had an eGFR <60 ml/min/1.73 m2 and 11 (1.1 %) patients an eGFR <45 ml/min/1.73 m2. Model A detected 543 patients: 81 with eGFR <60 ml/min/1.73 m2 (missing 11) and all 11 with eGFR <45 ml/min/1.73 m2. Model B detected 420 patients: 70 (missing 22) with eGFR <60 ml/min/1.73 m2 and all 11 with eGFR <45 ml/min/1.73 m2. Associations were significant (p < 0.05). CONCLUSIONS: Model B resulted in the lowest superfluous eGFR measurements while detecting all patients with eGFR <45 ml/min/1.73 m2 and nearly all with eGFR <60 ml/min/1.73 m2. KEY POINTS: • Less than 10% of patients undergoing contrast-enhanced CT have an eGFR of <60ml/min/1.73m 2 • Four risk factors can be used to detect pre-existent kidney disease • It is safe to reduce eGFR measurements using a four-risk-factor model.

Diffusion-weighted MRI to assess response to chemoradiotherapy in rectal cancer: main interpretation pitfalls and their use for teaching.

OBJECTIVES: To establish the most common image interpretation pitfalls for non-expert readers using diffusion-weighted imaging (DWI) to assess response to chemoradiotherapy in patients with rectal cancer and to explore the use of these pitfalls in an expert teaching setting. METHODS: Two independent non-expert readers (R1 and R2) scored the restaging DW MRI scans (b1,000 DWI, in conjunction with ADC maps and T2-W MRI scans for anatomical reference) in 100 patients for the likelihood of a complete response versus residual tumour using a five-point confidence score. The readers received expert feedback and the final response outcome for each case. The supervising expert documented any potential interpretation errors/pitfalls discussed for each case to identify the most common pitfalls. RESULTS: The most common pitfalls were the interpretation of low signal on the ADC map, small susceptibility artefacts, T2 shine-through effects, suboptimal sequence angulation and collapsed rectal wall. Diagnostic performance (area under the ROC curve) was 0.78 (R1) and 0.77 (R2) in the first 50 patients and 0.85 (R1) and 0.85 (R2) in the final 50 patients. CONCLUSIONS: Five main image interpretation pitfalls were identified and used for teaching and feedback. Both readers achieved a good diagnostic performance with an AUC of 0.85. KEY POINTS: • Fibrosis appears hypointense on an ADC map and should not be mistaken for tumour. • Susceptibility artefacts on rectal DWI are an important potential pitfall. • T2 shine-through on rectal DWI is an important potential pitfall. • These pitfalls are useful to teach non-experts how to interpret rectal DWI.

Lowering iodinated contrast concentration in infrainguinal endovascular interventions: a three-armed randomized controlled non-inferiority trial.

OBJECTIVES: To determine the influence of lowering iodinated contrast concentration on confidence of interventional radiologists in diagnosing and treating lesions during endovascular interventions in patients with symptomatic peripheral arterial disease (PAD). METHODS: A randomized controlled non-inferiority trial was performed in 60 patients. Intervention was performed with contrast concentrations (in mg of iodine per mL, mgI/mL) of 300 (standard), 240, or 140 mgI/mL. Primary outcome was confidence (score 0-100 %) of radiologists in diagnosing and treating arterial lesions. Secondary outcomes were procedural iodine load and image quality (i.e. non-diagnostic, limited, diagnostic, exemplary). RESULTS: Median confidence scores in diagnosing lesions were 100 % (range 81-100 %) for the 300 group (n = 21), 100 % (range 82-100 %) for the 240 group (n = 19), and 100 % (range 91-100 %) for the 140 group (n = 20) (both p = 1.00 compared to the 300 group). Median scores for treating lesions in the 240 and 140 groups, 100 % (range 79-100 %, p = 0.40), and 100 % (range 63-100 %, p = 0.25), respectively, were not lower compared to the 300 group (median 100 %, range 78-100 %). Procedural iodine load was lower in the 240 (24.3 ± 7.6 g, p = 0.022) and 140 groups (17.8 ± 5.6 g, p < 0.001) compared to the 300 group (29.7 ± 6.3 g). Image quality was diagnostic for all groups. CONCLUSION: Using iodine contrast of 140 mgI/mL for diagnosis and interventions in PAD patients significantly reduces administered iodine load without compromising image quality. Future use of lower iodine dose is recommended. KEY POINTS: • Lower iodinated contrast concentration during endovascular intervention does not decrease radiologist's confidence. • Image quality of standardized angiographies remains diagnostic using 140 mgI/mL iodinated contrast concentration. • Iodine load during intervention can be decreased by >40 % when using 140 mgI/mL. • Implementing the use of a lower iodinated contrast concentration will reduce the costs of the procedure.

Burden of waiting for surveillance CT colonography in patients with screen-detected 6-9 mm polyps.

PURPOSE: We assessed the burden of waiting for surveillance CT colonography (CTC) performed in patients having 6-9 mm colorectal polyps on primary screening CTC. Additionally, we compared the burden of primary and surveillance CTC. MATERIALS AND METHODS: In an invitational population-based CTC screening trial, 101 persons were diagnosed with <3 polyps 6-9 mm, for which surveillance CTC after 3 years was advised. Validated questionnaires regarding expected and perceived burden (5-point Likert scales) were completed before and after index and surveillance CTC, also including items on burden of waiting for surveillance CTC. McNemar's test was used for comparison after dichotomization. RESULTS: Seventy-eight (77 %) of 101 invitees underwent surveillance CTC, of which 66 (85 %) completed the expected and 62 (79 %) the perceived burden questionnaire. The majority of participants (73 %) reported the experience of waiting for surveillance CTC as 'never' or 'only sometimes' burdensome. There was almost no difference in expected and perceived burden between surveillance and index CTC. Waiting for the results after the procedure was significantly more burdensome for surveillance CTC than for index CTC (23 vs. 8 %; p = 0.012). CONCLUSION: Waiting for surveillance CTC after primary CTC screening caused little or no burden for surveillance participants. In general, the burden of surveillance and index CTC were comparable. KEY POINTS: • Waiting for surveillance CTC within a CRC screening caused little burden • The vast majority never or only sometimes thought about their polyp(s) • In general, the burden of index and surveillance CTC were comparable • Awaiting results was more burdensome for surveillance than for index CTC.

Computer tomography colonography participation and yield in patients under surveillance for 6-9 mm polyps in a population-based screening trial.

PURPOSE: Surveillance CT colonography (CTC) is a viable option for 6-9 mm polyps at CTC screening for colorectal cancer. We established participation and diagnostic yield of surveillance and determined overall yield of CTC screening. MATERIAL AND METHODS: In an invitational CTC screening trial 82 of 982 participants harboured 6-9 mm polyps as the largest lesion(s) for which surveillance CTC was advised. Only participants with one or more lesion(s) ≥6 mm at surveillance CTC were offered colonoscopy (OC); 13 had undergone preliminary OC. The surveillance CTC yield was defined as the number of participants with advanced neoplasia in the 82 surveillance participants, and was added to the primary screening yield. RESULTS: Sixty-five of 82 participants were eligible for surveillance CTC of which 56 (86.2 %) participated. Advanced neoplasia was diagnosed in 15/56 participants (26.8 %) and 9/13 (69.2 %) with preliminary OC. Total surveillance yield was 24/82 (29.3 %). No carcinomas were detected. Adding surveillance results to initial screening CTC yield significantly increased the advanced neoplasia yield per 100 CTC participants (6.1 to 8.6; p < 0.001) and per 100 invitees (2.1 to 2.9; p < 0.001). CONCLUSION: Surveillance CTC for 6-9 mm polyps has a substantial yield of advanced adenomas and significantly increased the CTC yield in population screening. KEY POINTS: • The participation rate in surveillance CT colonography (CTC) is 86 %. • Advanced adenoma prevalence in a 6-9 mm CTC surveillance population is high. • Surveillance CTC significantly increases the yield of population screening by CTC. • Surveillance CTC for 6-9 mm polyps is a safe strategy. • Surveillance CTC is unlikely to yield new important extracolonic findings.

Evolution of Screen-Detected Small (6-9 mm) Polyps After a 3-Year Surveillance Interval: Assessment of Growth With CT Colonography Compared With Histopathology.

OBJECTIVES: Volumetric growth assessment has been proposed for predicting advanced histology at surveillance computed tomography (CT) colonography (CTC). We examined whether is it possible to predict which small (6-9 mm) polyps are likely to become advanced adenomas at surveillance by assessing volumetric growth. METHODS: In an invitational population-based CTC screening trial, 93 participants were diagnosed with one or two 6-9 mm polyps as the largest lesion(s). They were offered a 3-year surveillance CTC. Participants in whom surveillance CTC showed lesion(s) of ≥6 mm were offered colonoscopy. Volumetric measurements were performed on index and surveillance CTC, and polyps were classified into growth categories according to ±30% volumetric change (>30% growth as progression, 30% growth to 30% decrease as stable, and >30% decrease as regression). Polyp growth was related to histopathology. RESULTS: Between July 2012 and May 2014, 70 patients underwent surveillance CTC after a mean surveillance interval of 3.3 years (s.d. 0.3; range 3.0-4.6 years). In all, 33 (35%) of 95 polyps progressed, 36 (38%) remained stable, and 26 (27%) regressed, including an apparent resolution in 13 (14%) polyps. In 68 (83%) of the 82 polyps at surveillance, histopathology was obtained; 15 (47%) of 32 progressing polyps were advanced adenomas, 6 (21%) of 28 stable polyps, and none of the regressing polyps. CONCLUSIONS: The majority of 6-9 mm polyps will not progress to advanced neoplasia within 3 years. Those that do progress to advanced status can in particular be found among the lesions that increased in size on surveillance CTC.

Monitoring treatment response in patients undergoing chemoradiotherapy for locally advanced uterine cervical cancer by additional diffusion-weighted imaging: A systematic review.

PURPOSE: To determine the role of diffusion-weighted imaging (DWI) in evaluating response to chemoradiotherapy in patients with uterine cervical cancer. MATERIALS AND METHODS: A search was performed in MEDLINE and EMBASE from January 2005 to April 2014 using search terms related to uterine cervical cancer and magnetic resonance imaging. Two reviewers independently checked the studies for inclusion criteria, patient population, magnetic resonance imaging (MRI) parameters and analysis, follow-up for treatment response, apparent diffusion coefficient (ADC) values, and quality assessment. RESULTS: Nine studies with 231 patients were included. International Federation of Gynecology and Obstetrics (FIGO) staging varied from Ib1 to IVb and mean age from 42 to 67 years. When baseline and after treatment pooled mean ADC values were compared, complete responders showed higher increase (0.88 × 10(-3) mm(2) /s to 1.50 × 10(-3) mm(2) /s; Δ0.62 × 10(-3) mm(2) /s) compared to partial responders (1.03 × 10(-3) mm(2) /s to 1.42 × 10(-3) mm(2) /s; Δ0.39 × 10(-3) mm(2) /s) and to nonresponders (0.87 × 10(-3) mm(2) /s to 1.18 × 10(-3) mm(2) /s; Δ0.31 × 10(-3) mm(2) /s). Individual studies also showed that an ADC of ≤0.31 was only seen in nonresponders and an increase of ADC of ≥0.62 was only seen in complete responders. The number of datasets for monitoring early response (at 2 or 4 weeks of therapy) were low and comparable increases in pooled mean ADC values between complete responders, partial responders, and nonresponders were seen. Data on quality assessment showed high risk of bias concerning patient selection, DWI evaluation, and flow and timing. CONCLUSION: DWI can be used for monitoring treatment response after treatment, but not for the early response monitoring.

Training readers to improve their accuracy in grading Crohn's disease activity on MRI.

OBJECTIVES: To prospectively evaluate if training with direct feedback improves grading accuracy of inexperienced readers for Crohn's disease activity on magnetic resonance imaging (MRI). METHODS: Thirty-one inexperienced readers assessed 25 cases as a baseline set. Subsequently, all readers received training and assessed 100 cases with direct feedback per case, randomly assigned to four sets of 25 cases. The cases in set 4 were identical to the baseline set. Grading accuracy, understaging, overstaging, mean reading times and confidence scores (scale 0-10) were compared between baseline and set 4, and between the four consecutive sets with feedback. Proportions of grading accuracy, understaging and overstaging per set were compared using logistic regression analyses. Mean reading times and confidence scores were compared by t-tests. RESULTS: Grading accuracy increased from 66 % (95 % CI, 56-74 %) at baseline to 75 % (95 % CI, 66-81 %) in set 4 (P = 0.003). Understaging decreased from 15 % (95 % CI, 9-23 %) to 7 % (95 % CI, 3-14 %) (P < 0.001). Overstaging did not change significantly (20 % vs 19 %). Mean reading time decreased from 6 min 37 s to 4 min 35 s (P < 0.001). Mean confidence increased from 6.90 to 7.65 (P < 0.001). During training, overall grading accuracy, understaging, mean reading times and confidence scores improved gradually. CONCLUSIONS: Inexperienced readers need training with at least 100 cases to achieve the literature reported grading accuracy of 75 %. KEY POINTS: • Most radiologists have limited experience of grading Crohn's disease activity on MRI. • Inexperienced readers need training in the MRI assessment of Crohn's disease. • Grading accuracy, understaging, reading time and confidence scores improved during training. • Radiologists and residents show similar accuracy in grading Crohn's disease. • After 100 cases, grading accuracy can be reached as reported in the literature.

Prediction of presence of kidney disease in a general patient population undergoing intravenous iodinated contrast enhanced computed tomography.

OBJECTIVE: To assess which risk factors can be used to reduce superfluous estimated glomerular filtration rate (eGFR) measurements before intravenous contrast medium administration. METHODS: In consecutive patients, all decreased eGFR risk factors were assessed: diabetes mellitus (DM), history of urologic/nephrologic disease (HUND), nephrotoxic medication, cardiovascular disease, hypertension, age > 60 years, anaemia, malignancy and multiple myeloma/M. Waldenström. We studied four models: (1) all risk factors, (2) DM, HUND, hypertension, age > 60 years; (3) DM, HUND, cardiovascular disease, hypertension; (4) DM, HUND, age > 75 years and congestive heart failure. For each model, association with eGFR < 60 ml/min/1.73 m(2) or eGFR < 45 ml/min/1.73 m(2) was studied. RESULTS: A total of 998 patients, mean age 59.94 years were included; 112 with eGFR < 60 ml/min/1.73 m(2) and 30 with eGFR < 45 ml/min/1.73 m(2). Model 1 detected 816 patients: 108 with eGFR < 60 ml/min/1.73 m(2) and all 30 with eGFR < 45 ml/min/1.73 m(2). Model 2 detected 745 patients: 108 with eGFR < 60 ml/min/1.73 m(2) and all 30 with eGFR < 45 ml/min/1.73 m(2). Model 3 detected 622 patients: 100 with eGFR < 60 ml/min/1.73 m(2) and all 30 with eGFR < 45 ml/min/1.73 m(2). Model 4 detected 440 patients: 86 with eGFR < 60 ml/min/1.73 m(2) and all 30 with eGFR < 45 ml/min/1.73 m(2). Associations were significant (p < 0.001). CONCLUSION: Model 4 is most effective, resulting in the lowest proportion of superfluous eGFR measurements while detecting all patients with eGFR < 45 ml/min/1.73 m(2) and most with eGFR < 60 ml/min/1.73 m(2). KEY POINTS: A major risk factor for contrast-induced nephropathy (CIN) is kidney disease. Risk factors are used to identify patients with pre-existent kidney disease. Evidence for risk factors to identify patients with kidney disease is limited. The number of eGFR measurements to detect kidney disease can be reduced.

Evaluation of conventional, dynamic contrast enhanced and diffusion weighted MRI for quantitative Crohn's disease assessment with histopathology of surgical specimens.

OBJECTIVES: To prospectively compare conventional MRI sequences, dynamic contrast enhanced (DCE) MRI and diffusion weighted imaging (DWI) with histopathology of surgical specimens in Crohn's disease. METHODS: 3-T MR enterography was performed in consecutive Crohn's disease patients scheduled for surgery within 4 weeks. One to four sections of interest per patient were chosen for analysis. Evaluated parameters included mural thickness, T1 ratio, T2 ratio; on DCE-MRI maximum enhancement (ME), initial slope of increase (ISI), time-to-peak (TTP); and on DWI apparent diffusion coefficient (ADC). These were compared with location-matched histopathological grading of inflammation (AIS) and fibrosis (FS) using Spearman correlation, Kruskal-Wallis and Chi-squared tests. RESULTS: Twenty patients (mean age 38 years, 12 female) were included and 50 sections (35 terminal ileum, 11 ascending colon, 2 transverse colon, 2 descending colon) were matched to AIS and FS. Mural thickness, T1 ratio, T2 ratio, ME and ISI correlated significantly with AIS, with moderate correlation (r = 0.634, 0.392, 0.485, 0.509, 0.525, respectively; all P < 0.05). Mural thickness, T1 ratio, T2 ratio, ME, ISI and ADC correlated significantly with FS (all P < 0.05). CONCLUSIONS: Quantitative parameters from conventional, DCE-MRI and DWI sequences correlate with histopathological scores of surgical specimens. DCE-MRI and DWI parameters provide additional information. KEY POINTS: • Conventional MR enterography can be used to assess Crohn's disease activity. • Several MRI parameters correlate with inflammation and fibrosis scores from histopathology. • Dynamic contrast enhanced imaging and diffusion weighted imaging give additional information. • Quantitative MRI parameters can be used as biomarkers to evaluate Crohn's disease activity.

Non-invasive evaluation of liver fibrosis: a comparison of ultrasound-based transient elastography and MR elastography in patients with viral hepatitis B and C.

OBJECTIVE: To compare the diagnostic accuracy of TE and MRE and establish cutoff levels and diagnostic strategies for both techniques, enabling selection of patients for liver biopsy. METHODS: One hundred three patients with chronic hepatitis B or C and liver biopsy were prospectively included. Areas under curves (AUROC) were compared for TE and MRE for METAVIR fibrosis grade ≥ F2 and ≥F3. We defined cutoff values for selection of patients with F0-F1 (sensitivity >95%) and for significant fibrosis F2-F4 (specificity >95%). RESULTS: Following exclusions, 85 patients were analysed (65 CHB, 19 CHC, 1 co-infected). Fibrosis stages were F0 (n = 3), F1 (n = 53), F2 (n = 15), F3 (n = 8) and F4 (n = 6). TE and MRE accuracy were comparable [AUROCTE ≥ F2: 0.914 (95% CI: 0.857-0.972) vs. AUROCMRE ≥ F2: 0.909 (0.840-0.977), P = 0.89; AUROCTE ≥ F3: 0.895 (0.816-0.974) vs. AUROCMRE ≥ F3: 0.928 (0.874-0.982), P = 0.42]. Cutoff values of <5.2 and ≥8.9 kPa (TE) and <1.66 and ≥2.18 kPa (MRE) diagnosed 64% and 66% of patients correctly as F0-F1 or F2-F4. A conditional strategy in inconclusive test results increased diagnostic yield to 80%. CONCLUSION: TE and MRE have comparable accuracy for detecting significant fibrosis, which was reliably detected or excluded in two-thirds of patients. A conditional strategy further increased diagnostic yield to 80%. KEY POINTS: • Both ultrasound-based transient elastography and magnetic resonance elastography can assess hepatic fibrosis. • Both have comparable accuracy for detecting liver fibrosis in viral hepatitis. • The individual techniques reliably detect or exclude significant liver fibrosis in 66 %. • A conditional strategy for inconclusive findings increases the number of correct diagnoses.

Accuracy of abdominal ultrasound and MRI for detection of Crohn disease and ulcerative colitis in children.

BACKGROUND: Endoscopy is currently the primary diagnostic technique for inflammatory bowel disease (IBD) in children. OBJECTIVE: To assess the accuracy of US and dynamic contrast-enhanced MRI for diagnosing inflammatory bowel disease and for distinguishing Crohn disease and ulcerative colitis in comparison to a reference standard. MATERIALS AND METHODS: Consecutive children with suspected IBD underwent diagnostic workup including ileocolonoscopy and upper gastrointestinal endoscopy as the reference standard, abdominal US, and MR enterography and colonography at 3 T. The protocol included a dynamic contrast-enhanced 3-D sequence. Sensitivity, specificity and kappa values were calculated for one ultrasonographer and two MRI observers. RESULTS: We included 28 children (15 boys) with mean age 14 years (range 10-17 years). The diagnosis was IBD in 23 children (72%), including 12 with Crohn disease, 10 with ulcerative colitis and 1 with indeterminate colitis. For the diagnosis of inflammatory bowel disease the sensitivity was 55% for US and 57% (both observers) for MR entero- and colonography, and the specificity was 100% for US and 100% (observer 1) and 75% (observer 2) for MR entero- and colonography. Combined MRI and US had sensitivity and specificity of 70% and 100% (observer 1) and 74% and 80% (observer 2), respectively. With the addition of a dynamic contrast-enhanced MR sequence, the sensitivity increased to 83% and 87%. US and MRI could only distinguish between Crohn disease and ulcerative colitis when terminal ileum lesions were present. CONCLUSION: US and MR entero- and colonography have a high accuracy for diagnosing inflammatory bowel disease in children but cannot be used to distinguish Crohn disease and ulcerative colitis.

Added Value of Liver MRI in Patients Eligible for Surgical Resection or Ablation of Colorectal Liver Metastases Based on CT: A Systematic Review and Meta-Analysis.

Background: Abdominal computed tomography (CT) is the standard imaging modality for detection and staging in patients with colorectal liver metastases (CRLM). Although liver magnetic resonance imaging (MRI) is superior to CT in detecting small lesions, guidelines are ambiguous regarding the added value of an additional liver MRI in the surgical workup of patients with CRLM. Therefore, this systematic review and meta-analysis aimed to evaluate the clinical added value of liver MRI in patients eligible for resection or ablation of CRLM based on CT. Methods: A systematic search was performed in the PubMed, Embase, and Cochrane Library databases through June 23, 2023. Studies investigating the impact of additional MRI on local treatment plan following CT in patients with CRLM were included. Risk of bias was assessed using the QUADAS-2 tool. The pooled weighted proportions for the primary outcome were calculated using random effect meta-analysis. Results: Overall, 11 studies with 1440 patients were included, of whom 468 patients (32.5%) were assessed for change in local treatment plan. Contrast-enhanced liver MRI was used in 10 studies, including gadoxetic acid in 9 studies. Liver MRI with diffusion-weighted imaging was used in 8 studies. Pooling of data found a 24.12% (95% confidence interval, 15.58%-32.65%) change in the local treatment plan based on the added findings of liver MRI following CT. Sensitivity analysis including 5 studies (268 patients) focusing on monophasic portal venous CT followed by gadoxetic acid-enhanced liver MRI with diffusion-weighted imaging showed a change of local treatment plan of 17.88% (95% confidence interval, 5.14%-30.62%). Conclusions: This systematic review and meta-analysis found that liver MRI changed the preinterventional local treatment plan in approximately one-fifth of patients eligible for surgical resection or ablation of CRLM based on CT. These findings suggest a clinically relevant added value of routine liver MRI in the preinterventional workup of CRLM, which should be confirmed by large prospective studies.