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Aim: To investigate the role of contrast enhanced ultrasound (CEUS) in evaluating patients with renal function impairment (RFI) showing: (1) acute renal failure (ARF) of suspicious vascular origin; or (2) suspicious renal lesions., Methods: We retrospectively evaluated patients addressed to CEUS over an eight years period to rule-out vascular causes of ARF (first group of 50 subjects) or assess previously found suspicious renal lesions (second group of 41 subjects with acute or chronic RFI). After preliminary grey-scale and color Doppler investigation, each kidney was investigated individually with CEUS, using 1.2-2.4 mL of a sulfur hexafluoride-filled microbubble contrast agent. Image analysis was performed in consensus by two readers who reviewed digital clips of CEUS. We calculated the detection rate of vascular abnormalities in the first group and performed descriptive statistics of imaging findings for the second group., Results: In the first group, CEUS detected renal infarction or cortical ischemia in 18/50 patients (36%; 95%CI: 23.3-50.9) and 1/50 patients (2%; 95%CI: 0.1-12), respectively. The detection rate of infarction was significantly higher ( P = 0.0002; McNemar test) compared to color Doppler ultrasonography (10%). No vascular causes of ARF were identified in the remaining 31/50 patients (62%). In the second group, CEUS detected 41 lesions on 39 patients, allowing differentiation between solid lesions (21/41; 51.2%) vs complex cysts (20/41; 48.8%), and properly addressing 15/39 patients to intervention when feasible based on clinical conditions (surgery and cryoablation in 13 and 2 cases, respectively). Cysts were categorized Bosniak II, IIF, III and IV in 8, 5, 4 and 3 cases, respectively. In the remaining two patients, CEUS found 1 pseudolesion and 1 subcapsular hematoma., Conclusion: CEUS showed high detection rate of renal perfusion abnormalities in patients with ARF, influencing the management of patients with acute or chronic RFI and renal masses throughout their proper characterization., Competing Interests: Conflict-of-interest statement: Nothing to disclose.

Purpose: To investigate the agreement between Roach equations (RE) and multiparametric magnetic resonance imaging (mpMRI) in assessing the T-stage of prostate cancer (PCa)., Materials and Methods: Seventy-three patients with biopsy-proven PCa and previous RE assessment prospectively underwent mpMRI on a 3.0T magnet before external beam radiation therapy (EBRT). Using Cohen's kappa statistic, we assessed the agreement between RE and mpMRI in defining the T-stage (≥T3 vs.T≤2) and risk category according to the National comprehensive cancer network criteria (≤intermediate vs. ≥high). We also calculated sensitivity and specificity for ≥T3 stage in an additional group of thirty-seven patients with post-prostatectomy histological examination (mpMRI validation group)., Results: The agreement between RE and mpMRI in assessing the T stage and risk category was moderate (k=0.53 and 0.56, respectively). mpMRI changed the T stage and risk category in 21.9% (95%C.I. 13.4-33-4) and 20.5% (95%C.I. 12.3-31.9), respectively, prevalently downstaging PCa compared to RE. Sensitivity and specificity for ≥T3 stage in the mpMRI validation group were 81.8% (95%C.I. 65.1-91.9) and 88.5% (72.8-96.1)., Conclusion: RE and mpMRI show moderate agreement only in assessing the T-stage of PCa, translating into an mpMRI-induced change in risk assessment in about one fifth of patients. As supported by high sensitivity/specificity for ≥T3 stage in the validation group, the discrepancy we found is in favour of mpMRI as a tool to stage PCa before ERBT., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Aim: To investigate the type and timing of evolution of incidentally found branch-duct intraductal papillary mucinous neoplasms (bd-IPMN) of the pancreas addressed to magnetic resonance imaging cholangiopancreatography (MRCP) follow-up., Methods: We retrospectively evaluated 72 patients who underwent, over the period 2006-2016, a total of 318 MRCPs (mean 4.4) to follow-up incidental, presumed bd-IPMN without signs of malignancy, found or confirmed at a baseline MRCP examination. Median follow-up time was 48.5 mo (range 13-95 mo). MRCPs were acquired on 1.5T and/or 3.0T systems using 2D and/or 3D technique. Image analysis assessed the rates of occurrence over the follow-up of the following outcomes: (1) imaging evolution, defined as any change in cysts number and/or size and/or appearance; and (2) alert findings, defined as worrisome features and/or high risk stigmata ( e.g ., thick septa, parietal thickening, mural nodules and involvement of the main pancreatic duct). Time to outcomes was described with the Kaplan-Meir approach. Cox regression model was used to investigate clinical or initial MRCP findings predicting cysts changes., Results: We found a total of 343 cysts (per-patient mean 5.1) with average size of 8.5 mm (range 5-25 mm). Imaging evolution was observed in 32/72 patients (44.4%; 95%CI: 32-9-56.6), involving 47/343 cysts (13.7%). There was a main trend towards small (< 10 mm) increase and/or decrease of cysts size at a median time of 22.5 mo. Alert findings developed in 6/72 patients (8.3%; 95%CI: 3.4-17.9) over a wide interval of time (13-63 mo). No malignancy was found on endoscopic ultrasound with fine-needle aspiration (5/6 cases) or surgery (1/6 cases). No clinical or initial MRCP features were significantly associated with changes in bd-IPMN appearance ( P > 0.01)., Conclusion: Changes in MRCP appearance of incidental bd-IPNM were frequent over the follow-up (44.4%), with relatively rare (8.3%) occurrence of non-malignant alert findings that prompted further diagnostic steps. Changes occurred at a wide interval of time and were unpredictable, suggesting that imaging follow-up should be not discontinued, though MRCPs might be considerably delayed without a significant risk of missing malignancy., Competing Interests: Conflict-of-interest statement: Nothing to disclose.

Purpose: To investigate the impact of multiparametric magnetic resonance imaging (mpMRI) on risk group assessment of patients with prostate cancer (PCa) initially addressed to external beam radiation therapy (EBRT)., Materials and Methods: We prospectively performed mpMRI (3.0Tsystem) in 44 patients addressed to EBRT, using a multiparametric protocol (high-resolution multiplanar T2-weighted, diffusion-weighted and dynamic contrast-enhanced imaging). Risk group was assessed in accordance with the National comprehensive cancer network (NCCN) categories, by combining prostate-specific-antigen level, Gleason score and the T-stage as established by digital rectal examination (clinical risk assessment; c-RA) versus mpMRI (mpMRI-risk assessment; mpMRI-RA). The agreement between c-RA and mpMRI-RA was investigated using Cohen's kappa., Results: Patients were included in very low/low risk, intermediate risk, high risk, very high risk and metastatic NCCN categories in 10 (22.7%), 18 (40.9%), 15 (34.1%), 1 (2.3%) and 0 cases using c-RA vs. 8 (18.2%), 14 (31.8%), 14 (31.8%), 4 (9.1%) and 4 (9.1%) cases using mpMRI-RA, respectively, with only moderate agreement (k=0.43). mpMRI-RA determined risk downgrading in 2/44 patients (4.5%), and risk upgrading in 16/44 patients (36.3%). After mpMRI, EBRT remained indicated in all patients., Conclusion: mpMRI changed clinical risk stratification in about 41% of patients with PCa, with potential impact on EBRT planning., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Objectives: To estimate the impact on recall rate (RR) of digital breast tomosynthesis (DBT) associated with digital mammography (DM+DBT), compared to DM alone, evaluate the impact of double reading (DR) and review the literature., Methods: Ethics committees approved this multicenter study. Patients gave informed consent. Women recalled from population-based screening reading were included. Reference standard was histology and/or ≥ 1 year follow up. Negative multiple assessment was considered for patients lost at follow up. Two blinded readers (R1, R2) evaluated first DM and subsequently DM+DBT. RR, sensitivity, specificity, accuracy, positive and negative predictive values (PPV, NPV), were calculated for R1, R2, and DR. Cohen κ and χ(2) were used for R1-R2 agreement and RR related to breast density., Results: We included 280 cases (41 malignancies, 66 benign lesions, and 173 negative examinations). The RR reduction was 43% (R1), 58% (R2), 43% (DR). Sensitivity, specificity, accuracy, PPV and NPV were: 93%, 67%, 71%, 33%, 98% for R1; 88%, 73%, 75%, 36%, 97% for R2; 98%, 55%, 61%, 27%, 99% for DR. The agreement was higher for DM+DBT (κ=0.459 versus κ=0.234). Reduction in RR was independent from breast density (p=0.992)., Conclusion: DBT was confirmed to reduce RR, as shown by 13 of 15 previous studies (reported reduction 6-82%, median 31%). This reduction is confirmed when using DR. DBT allows an increased inter-reader agreement., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Objectives: To evaluate second-look digital breast tomosynthesis (SL-DBT) for additional findings (AFs) at preoperative MRI compared with second-look ultrasound (SL-US)., Methods: We included 135 patients with breast cancer who underwent digital mammography (DM), DBT, US, and MRI at two centres. MR images were retrospectively evaluated to find AFs, described as focus, mass, or non-mass; ≤10 mm or >10 mm in size; BI-RADS 3, 4, or 5. DM and DBT exams were reviewed looking for MRI AFs; data on SL-US were collected. Reference standard was histopathology or ≥12-month negative follow-up. Fisher exact test and McNemar test were used., Results: Eighty-four AFs were detected in 53/135 patients (39%, 95%CI 31-48%). A correlate was found for 44/84 (52%, 95%CI 41-63%) at SL-US, for 20/84 (24%, 95%CI 11-28%) at SL-DM, for 42/84 (50%, 95%CI 39-61%) at SL-DBT, for 63/84 (75%, 95%CI 64-84%) at SL-DBT, and/or SL-US, the last rate being higher than for SL-US only, overall (p < 0.001), for mass or non-mass, ≤ or >10 mm, BI-RADS 4 or 5, or malignant lesions (p < 0.031). Of 21 AFs occult at both SLs, 17 were malignant (81%, 95%CI 58-94%)., Conclusions: When adding SL-DBT to SL-US, AFs detection increased from 52% to 75%. MR-guided biopsy is needed for the remaining 25%., Key Points: • Detection rate of MRI AFs using SL-US was 52% • Adding SL-DBT, the detection rate of MRI AFs significantly increased to 75%. • Over 80% of the remaining 25% MRI AFs were malignant. • MR-guided biopsy should be used when SL-US and SL-DBT are inconclusive.

Objective: To present our technique of ureteral replacement with an appendicovesicostomy for the treatment of extended ureteral stricture after kidney transplantation. Ureteral stricture represents a urologic complication that may cause progressive function impairment and graft loss. Symptomatic ureteral stenosis is generally treated with a percutaneous nephrostomy and ureteral stenting. This approach may be initially effective, but often does not offer a long-term solution., Methods: A 48-year-old Caucasian man underwent kidney transplantation from a heart-beating deceased donor. The graft was transplanted to the right iliac fossa. Ureterovesical anastomosis was performed following the Lich-Gregoir technique. The postoperative period and follow-up were uneventful. Six months later the patient experienced an episode of acute pyelonephritis with hydronephrosis. A percutaneous nephrostomy was inserted, and an anterograde pyelography confirmed proximal dilatation with severe distal stenosis involving the entire ureter including the ureterovesical anastomosis. A 9 French Double-J stent was inserted antegradely and the patient was prepared for surgery., Results: We decided therefore to use the appendix as a conduit between the proximal transplant ureter and the bladder It was interposed with an isoperistaltic orientation and anastomosed to the ureter proximally and to the bladder distally (Lich-Gregoir reimplantation) using interrupted absorbable 5/0 sutures over a 10-Fr Double-J stent. The urethral catheter was removed on day 9 postoperatively and the patient was discharged with normal parameters. At 1 year follow-up the patient remains well., Conclusion: The positive outcome confirms how the use of appendix as ureteral replacement is feasible and effective, allowing the salvage of the renal allograft., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Purpose: To evaluate whether the variation of the apparent diffusion coefficient (ADC) values obtained with DWI can predict elevated levels of Ki67 proliferation index and aggressive subtypes in patients with breast cancer., Materials and Methods: Breast MRI studies of 115 patients (mean age 57.3 years, range 36-81 years) with a biopsy-proven breast cancers were evaluated in this retrospective IRB-approved study. Examinations were performed on a 1.5 T magnet and included a Single-Shot Echoplanar DWI sequence with b values of 0 and 1000 s/mm(2). For each target lesion, ADC was measured. ADC values were compared considering Ki67 status (≥20 % or <20 %), histology, grade (G1, G2 or G3) and clinical-pathological classification (Luminal A, Luminal B HER2-positive, Luminal B HER-2 negative, HER-2 enriched and Triple Negative). Mann-Whitney U test and Kruskal-Wallis test were used for comparisons and receiver operating characteristic (ROC) curves were obtained. Inter- and intra-reader variability was evaluated in a subset of 40 patients, using interclass correlation coefficient (ICC) and Bland-Altman plots., Results: Of 115 lesions, 53 (46.1 %) were assessed as Ki67 positive and 62 (53.9 %) as Ki67 negative. ADC values were significantly (p < 0.0001) lower in Ki67-positive patients (median 0.86 × 10(-3) mm(2)/s; interquartile range 0.75-0.92) compared to Ki67-negative (median 1.03 × 10(-3) mm(2)/s; interquartile range 0.92-1.13). Median ADC was also lower in G2 and G3 cancer and in the Luminal B Her2-negative subtype (p = 0.0015). No differences were found when evaluating histology. ROC curve showed a sensitivity and specificity of 83.0 and 66.1 %, respectively, when using a cutoff of 0.95 s/mm(2) to differentiate Ki67-positive from Ki67-negative cancers. Inter- and intra-reader variability was moderate (ICC = 0.623; ICC = 0.548, respectively). No systematic differences were identified with Bland-Altman plots., Conclusions: Lower ADC values are associated with elevated Ki67 proliferation index and more aggressive pathologic features. Moderate agreement in ADC measurement could be a limitation.

Background: Macrocystic serous cystadenomas (MaSCA) are rare benign tumor of the pancreas which represent an atypical macroscopic morphologic variant of serous cystadenomas (SCA). They are characterized by a limited number of cysts with a diameter of >2 cm and share imaging features overlapping those of mucinous cystic neoplasm (MCN) and branch-duct intraductal papillary mucinous neoplasm (BD-IPMN), thus frequently making the pre-operative radiologic diagnosis difficult., Materials and Methods: Four cases of MaSCA, which were surgically treated in our structure, are reported., Results: Two women (62 and 39 year-old) presented with upper abdominal pain and palpable mass underwent CT with evidence of a lobulated cystic neoformation (98 × 70 and 94 × 75 mm respectively) originating from the body and the tail of the pancreas respectively. They underwent distal pancreatectomy for suspected MCN. A 38 year-old woman underwent laparoscopic distal pancreatectomy because of the incidental finding of an unilocular cystic lesion in the pancreatic tail (23 mm) of indeterminate origin (MCN, SCA or metastasis). In a 40 year-old woman, admitted for acalculous acute pancreatitis, an unilocular cystic lesion in the body of the pancreas (62 mm) was detected and confirmed after 2 months at CT, therefore she underwent distal pancreatectomy for suspected pseudocyst or SCA. In all of the 4 patients the histological examination of the specimens revealed a MaSCA., Conclusion: Imaging techniques have a low diagnostic power in terms of differentiation of MaSCA from malignant lesions (as MCNs and BD-IPMN). In the clinical practise of MaSCA, surgery appears to gain indications that are wider than those correlated to the pathologic outcome, because of the necessity of a correct differential diagnosis from potentially malignant cystic tumors and the frequent symptoms requiring treatment., (Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.)

Diagnostic test accuracy, based on sensitivity, specificity, positive/negative predictive values (dichotomous case), and on ROC analysis (continuous case), should be expressed with a single, coherent index. We propose to modelize the diagnostic test as a flow of information between the disease, that is, a hidden state of the patient, and the physicians. We assume that (1) sensitivity, specificity, and false-positive/false-negative rates are the probabilities of a binary asymmetric channel; (2) the diagnostic channel information is measured by mutual information. We introduce two summary measures of accuracy, namely the information ratio (IR) for the dichotomous case, and the global information ratio (GIR) for the continuous case. We apply our model to a study by Pisano et al. (N Engl J Med 353(17):1773-1783, 2005), who compared digital versus film mammography, in diagnosing breast cancer in a screening population of 42,760 women. In film mammography, the maximum IR (0.178) corresponds to the standard cutoff of sensitivity and specificity provided by the ROC analysis (GIR 0.200). Maximum IR and GIR for digital mammography are higher (0.201 and 0.229, respectively), but IR corresponds to a cutoff with higher sensitivity but lower specificity, thus suggesting that larger information provided by digital mammography carries the risk of more false-positive cases.

An ever-increasing number of 3.0 Tesla (T) magnets are installed worldwide. Moving from the standard of 1.5 T to higher field strength implies a number of potential advantage and drawbacks, requiring careful optimization of imaging protocols or implementation of novel hardware components. Clinical practice and literature review suggest that state-of-the-art 3.0 T is equivalent to 1.5 T in the assessment of focal liver lesions and diffuse liver disease. Therefore, further technical improvements are needed in order to fully exploit the potential of higher field strength.

Purpose: This study was done to evaluate test-retest reliability of liver diffusion tensor imaging (LDTI)., Materials and Methods: Ten healthy volunteers (median age 23 years) underwent two LDTI scans on a 3.0 T magnet during two imaging sessions separated by 2 weeks (session-1/-2, respectively). Fifteen gradient directions and b values of 0-1,000 s/mm(2) were used. Two radiologists in consensus assessed liver apparent diffusion coefficient (ADC) and fraction of anisotropy (FA) values on ADC and FA maps at four reference levels, namely: right upper level (RUL), right lower level (RLL), left upper level (LUL) and left lower level (LLL). We then assessed (a) whether ADC and FA values overlapped when measured on different levels within the same imaging session or between different imaging sessions; (b) the degree of variability on an intra-session and inter-session basis, respectively, using the coefficient of variation (CV)., Results: In sessions 1 and 2, the ADC/FA values were significantly larger in the left liver lobe (LUL/LLL) compared to right liver lobe (RUL/RLL) (p < 0.05/6). Intra-session CVs were 9.51 % (session 1) and 9.73 % (session 2) for ADC, and 12.93 % (session 1) and 11.82 % (session 2) for FA, respectively. When comparing RUL, RLL, LUL and LLL on an inter-session basis, CVs were 6.52, 8.20, 6.52 and 11.06 % for ADC, and 15.42, 15.80, 15.42 and 6.80 % for FA, respectively., Conclusion: LDTI provides consistent and repeatable measurements. However, since larger left lobe ADC/FA values can be attributed to artefacts, right lobe values should be considered the most reliable measurements of water diffusivity within the liver.

Despite advances in patient and graft management, biliary complications (BC) still represent a challenge both in the early and delayed period after orthotopic liver transplantation (OLT). Because of unspecific clinical presentation, imaging is often mandatory in order to diagnose BC. Among imaging modalities, magnetic resonance cholangiography (MRC) has gained widespread acceptance as a tool to represent the reconstructed biliary tree noninvasively, using both the conventional technique (based on heavily T2-weighted sequences) and contrast-enhanced MRC (based on the acquisition of T1-weighted sequences after the administration of hepatobiliary contrast agents). On this basis, MRC is generally indicated to: (1) avoid unnecessary procedures of direct cholangiography in patients with a negative examination and/or identify alternative complications; and (2) provide a road map for interventional procedures or surgery. As illustrated in the review, MRC is accurate in the diagnosis of different types of biliary complications, including anastomotic strictures, non-anastomotic strictures, leakage and stones.

Purpose: This study was undertaken to evaluate whether magnetic resonance (MR) imaging is able to rule out malignancy in the case of BI-RADS 3 microcalcifications, providing a sufficient negative predictive value (NPV) for early work-up, and to reduce unnecessary stereotactically guided vacuum-assisted biopsy (SVAB) procedures., Materials and Methods: We prospectively enrolled consecutive women with BI-RADS 3 microcalcifications, who subsequently underwent MR imaging and SVAB. The MR studies were reviewed according to the MR-BI-RADS classification system; lesions assessed as MR-BI-RADS 1 and 2 were considered negative for malignancy, categories MR-BI-RADS 3, 4 and 5 indicated malignant lesions. The presence of additional findings was recorded. Histologic analysis and follow-up were the reference standard. MR sensitivity, specificity, positive predictive value (PPV) and NPV were calculated., Results: The final population consisted of 71 lesions. Histologic analysis showed malignancy in six cases (malignancy rate 8%). At MR analysis, 60 (85%) lesions were considered negative for malignancy and 11 (15%) malignant. Additional MR imaging findings were identified in 19 (27%) patients, all corresponding to nonmalignant lesions. MR sensitivity was 33%, specificity 86%, PPV 18% and NPV 93%., Conclusions: Because of its relatively low NPV, MR imaging is not able to safely exclude malignancy in the case of BI-RADS 3 microcalcifications. The relatively high malignancy rate found in this study might support SVAB in the case of BI-RADS 3 microcalcifications.

Orthotopic liver transplantation (OLT) represents a major treatment for end-stage chronic liver disease, as well as selected cases of hepatocellular carcinoma and acute liver failure. The ever-increasing development of imaging modalities significantly contributed, over the last decades, to the management of recipients both in the pre-operative and post-operative period, thus impacting on graft and patients survival. When properly used, imaging modalities such as ultrasound, multidetector computed tomography, magnetic resonance imaging (MRI) and procedures of direct cholangiography are capable to provide rapid and reliable recognition and treatment of vascular and biliary complications occurring after OLT. Less defined is the role for imaging in assessing primary graft dysfunction (including rejection) or chronic allograft disease after OLT, e.g., hepatitis C virus (HCV) recurrence. This paper: (1) describes specific characteristic of the above imaging modalities and the rationale for their use in clinical practice; (2) illustrates main imaging findings related to post-OLT complications in adult patients; and (3) reviews future perspectives emerging in the surveillance of recipients with HCV recurrence, with special emphasis on MRI.

Purpose: This study was done to assess the feasibility of three-dimensional ultrasonography (3D-US) for volume calculation of solid breast lesions., Materials and Methods: The volumes of 36 malignant lesions were measured using conventional 2D-US, 3D-US and magnetic resonance imaging (MRI) and compared with that obtained with histology (standard of reference). With 2D Ultrasouns, volume was estimated by measuring three diameters and calculating volume with the mathematical formula for spheres. With 3D-US, stored images were retrieved and boundaries of masses were manually outlined; volume calculation was performed with VOCAL software. For MRI, volume measurements were obtained with special software for 3D reconstructions, after each lesion had been manually outlined. Histology measured the three main diameters and the volume was estimated using the mathematical formula for spheres. Interclass correlation coefficient (ICC) and Bland-Altman plots were used to assess agreement between the volumes measured., Results: ICC indicated that a good level of concordance was identified between 3D-US and histology (0.79). According to the Bland-Altman analysis, limits of agreement of mean differences of the volumes measured with the three imaging modalities were comparable with histology: -2 ÷ 1.5 cm(3) for 3D-US; -2.3 ÷ 1.3 cm(3) for 2D-US and -2.2 ÷ 1.6 cm(3) for MRI., Conclusions: 3D-US is a reliable method for the volumetric assessment of breast lesions. 3D-US is able to provide valuable information for the preoperative evaluation of lesions.

We investigated whether diffusion-weighted Imaging (DWI) adds diagnostic confidence in assessing focal liver lesions (FLLs). By reviewing FLLs without and with DWI at 1.5 T, two radiologists scored the confidence in diagnosing benignancy/malignancy (confidence score), and DWI usefulness (usefulness score). We showed that adding DWI significantly decreased the confidence score of the most experienced radiologist and increased his confidence in false-negative diagnoses showing atypical features on conventional magnetic resonance imaging., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose: To quantify the impact of diagnostic confidence on radiological diagnosis with a fuzzy logic-based method., Materials and Methods: Twenty-two oncologic patients with 20 cysts and 30 metastases ≤1 cm in size found at 64-row computed tomography were included. Two readers (R1/R2) expressed diagnoses as a subjective level of confidence P(d) in malignancy within the interval [0,1] rather than on a "crisp" basis (malignant/benign); confidence in benignancy was 1 - p(d). When cross-tabulating data according to the standard of reference, 2 × 2 table cells resulted from the aggregation between p(d)/1 - p(d) and final diagnosis. We then assessed (i) readers diagnostic performance on a fuzzy and crisp basis; (ii) the "divergence" δ(F, C) (%) as a measure of how confidence impacted on crisp diagnosis., Results: Diagnoses expressed with lower confidence increased fuzzy false positives compared to crisp ones (from 0 to 0.2 for R1; from 1 to 2.4 for R2). Crisp/fuzzy accuracy was 94.0%/93.6% (R1) and 94.0/91.6% (R2). δ(F, C) (%) was larger in the case of the less experienced reader (R2) (up to +7.95% for specificity). According to simulations, δ(F, C) (%) was negative/positive depending on the level of confidence in incorrect diagnoses., Conclusion: Fuzzy evaluation shows a measurable effect of uncertainty on radiological diagnoses.

Purpose: The authors compared the accuracy of diffusion-weighted imaging (DWI) visual analysis (VA) vs. apparent diffusion coefficient quantification (ADC-Q) in assessing malignancy of solid focal liver lesions (FLLs)., Materials and Methods: Using a 1.5-T system, two radiologists retrospectively assessed as benign or malignant 50 solid FLLs: (a) by VA of signal intensity on DWI images at b=800 s/mm(2) and ADC map; (b) by quantifying lesion ADC. Reference standard included histology or follow-up confirmation of diagnosis by a consensus panel. Receiver operating characteristic (ROC) curve analysis was performed., Results: because of 20 false-negative hepatocellular carcinomas, VA showed lower accuracy than ADC-Q (52.0% VS. 68.0%). however, stratified accuracy for metastases was higher with VA (75.0 VS. 66%). ADC and signal features of malignant and benign FLLs were found to largely overlap., Conclusions: VA performed worse than ADC-Q for hepatocellular carcinoma and better for metastases. Overall, the accuracy of both methods was limited because of the overlap in visual appearance and ADC values between solid benign and malignant FLLs.

We retrospectively compared the accuracy of two computer-aided detection (CAD) systems for the detection of malignant breast lesions on full-field digital mammograms. Mammograms of 326 patients were analyzed (117 patients with breast cancer, 209 negative cases), and each set of cases was read by two CAD systems (Second Look versus AccuDetect Galileo). True-positive fractions per image and case for soft densities, microcalcifications, and total cancers were assessed. Study results showed better overall performance of AccuDetect Galileo (when compared to Second Look) in detecting masses, microcalcifications, and all cancer types, especially in extremely dense breast parenchyma., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: To identify magnetic resonance (MR) imaging (MRI) features of radial sclerosing lesions (RSLs) of the breast., Methods and Materials: The radiologic and pathologic records for 4629 consecutive patients undergoing MR examinations of the breast were retrospectively reviewed. Patients who received a pathologic diagnosis of RSL without atypia or carcinoma at surgical excision were identified. The MR images were evaluated according to the BI-RADS-MRI lexicon by two experienced breast radiologists. The frequency of morphologic and kinetic patterns and of BI-RADS-MRI assessment categories was calculated., Results: Twenty-nine patients with 29 surgically excised RSL were identified. Nine (31%) RSL were MR-occult; the remaining 20 (69%) RSL presented as masses (10/20, 50%), architectural distortions (5/20, 25%), non-mass lesions (4/20, 20%), and focus (1/20, 5%). Kinetic analysis was performed in 18 RSL: enhancement features were benign in 9 (50%) cases, suspicious in 7 (39%) cases and indeterminate in 2 (11%) cases. Twelve (41%) MR examinations were assessed as suspicious (BI-RADS-MRI 4 and 5), and 17 (59%) as negative (BI-RADS-MRI 1) or benign (BI-RADS-MRI 2 and 3)., Conclusion: RSLs are often visualized on MR imaging. Just as in mammography and sonography, RSL can have variable morphologic and kinetic features, and not infrequently they can mimic invasive carcinoma of the breast., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To investigate the negative predictive value (NPV) for malignancy of 3.0 Tesla (T) MRI in patients with "gray zone" PSA level and prior negative biopsies., Materials and Methods: We enrolled 26 patients with PSA level between 2.5 and 10 ng/mL and no cancer at previous biopsies. Examinations were performed on a 3.0T system using T2-weighted imaging, diffusion-weighted imaging, spectroscopy, and postcontrast dynamic study. A regional scheme was used to record MRI findings and to perform subsequent transrectal-ultrasonography-guided biopsy. Based on the matching between imaging and biopsy findings we estimated MRI predictive values, sensitivity, specificity and accuracy on a per-patient and per-region basis., Results: On a per patient basis, MRI had five true-positive (5/26; 19.2%), eight true-negative (8/26; 30.8%) and no false-negative cases, corresponding to a NPV and sensitivity of 100% each. Thirteen patients were assessed as false-positive cases (13/26; 50.0%) (specificity of 38.1%). Five of them (5/26; 19.2%) showed high-grade prostatic intraepithelial neoplasia (HGPIN) and atypical small-acinar proliferation (ASAP) at biopsy. T2-weighted imaging alone showed per-region NPV (96.8%)., Conclusion: Because of the high NPV, MRI had the potential to avoid unnecessary biopsy in approximately one-third of "gray-zone" patients with a negative examination. Additionally, MRI was useful to address to biopsy more than one-third of patients with cancer or high-risk lesions as HGPIN and ASAP., (Copyright © 2012 Wiley Periodicals, Inc.)

Purpose: This study assessed whether the degree of bile-duct dilatation in liver-transplanted patients is correlated with the time from intervention and the type of underlying biliary stricture., Methods and Materials: Fifty-seven 3D magnetic resonance cholangiograms (MRCs) performed on 42 liver-transplanted patients were retrospectively evaluated. Diameter was measured at the level of the extrahepatic bile duct (EBD), right hepatic duct (RHD), left hepatic duct (LHD), anterior and posterior right hepatic ducts (aRHD, pRHD) and left lateral and medial ducts (LLD, LMD). Data were stratified according to the type of biliary stricture (all types, anastomotic, ischaemic-like, mixed) and compared, on a per-examination basis: (a) between two groups based on time from transplantation using a 1-year threshold (nonlongitudinal analysis); (b) among 26 repeated examinations on 11 patients (longitudinal analysis); (c) among different stricture groups., Results: The biliary tree was slightly dilated within 1 year from transplantation (2.9±1.3 to 6.1±3.2 mm). In general, nonlongitudinal analysis showed minimally larger duct size after 1 year (mean +1.4±0.5 mm) despite significant differences at most sites of measurement considering all types of strictures (p<0.01; Mann-Whitney U test). Longitudinal analysis showed diameter increase over time, although without statistically significant differences (p>0.01; Kruskal-Wallis test). No significant difference in bile-duct size was observed when comparing types of stricture (p>0.01; Kruskal-Wallis test)., Conclusions: Biliary dilatation after liver transplantation is mild and develops slowly regardless of the underlying type of stricture, possibly in relation to graft properties. MRC has a potential role as first-line imaging modality for a reliable assessment of biliary dilatation and the presence of a stricture.

Objective: The purpose of this study is to evaluate the role of MRI for characterization of high-risk breast lesions diagnosed at imaging-guided needle biopsy., Materials and Methods: In this retrospective analysis of 220 patients, 227 high-risk lesions (94 papillomas, 64 radial sclerosing lesions, 46 lobular neoplasias, and 23 atypical ductal hyperplasias) found at 11-gauge vacuum-assisted or 14-gauge needle biopsy were studied with dynamic MRI (time resolution, 84 or 88 seconds; gadopentetate dimeglumine or gadobenate dimeglumine, 0.1 mmol/kg). When lesions showed contrast enhancement on subtracted images, they were considered suspicious for malignancy. The reference standard was histopathologic examination after surgical excision in 190 of 227 (84%) lesions and negative follow-up (≥ 24 months) in 37 of 227 (16%) lesions. Predictive values and likelihood ratios were calculated., Results: Of 227 lesions, 155 (68%) were contrast enhancing and 72 (32%) were not. Of 155 contrast-enhancing lesions, 28 (18%) were upgraded to malignancy after surgical excision (nine papillomas, one radial sclerosing lesion, 11 lobular neoplasias, and seven atypical ductal hyperplasias); there were 11 invasive carcinomas and 17 ductal carcinomas in situ, four of the latter being G3. Of 72 non-contrast-enhancing lesions, two (3%) were upgraded to malignancy after surgical excision (one radial sclerosing lesion and one lobular neoplasia), both of which were G1 ductal carcinoma in situ. Cancer probability was significantly higher for contrast-enhancing (18%) than for non-contrast-enhancing (3%) lesions (p = 0.001) and for nonmasslike (43%) than for masslike (14%) lesions (p = 0.005). The positive predictive value was 18% (28/155; 95% CI, 13-24%), the negative predictive value was 97% (70/72; 95% CI, 94-99%), the positive likelihood ratio was 1.448 (95% CI, 1.172-1.788), and the negative likelihood ratio was 0.188 (95% CI, 0.152-0.232)., Conclusion: The absence of enhancement at dynamic MRI allowed reliable exclusion of invasive cancers among high-risk lesions diagnosed at needle biopsy.

Objective: The purpose of this study was to investigate whether breast MRI can be used to rule out malignancy in patients with high-risk lesions diagnosed at imaging-guided core needle biopsy., Subjects and Methods: The subjects were women consecutively registered between October 2004 and April 2010 who had high-risk lesions diagnosed at mammographically or sonographically guided core needle biopsy and subsequently underwent MRI and surgical excision. MR images were reviewed by two experienced breast radiologists. Lesions assessed as BI-RADS category 1-3 were considered negative for malignancy, and BI-RADS 4 and 5 lesions were considered malignant. Histologic findings at surgical excision were the reference standard. The sensitivity, specificity, and positive and negative predictive values of MRI in the detection of associated malignancy were calculated for the entire set of lesions and for each histologic subtype., Results: The final sample consisted of 169 high-risk lesions in 166 patients. At MRI analysis, 116 (68.6%) lesions were considered negative for malignancy, and the other 53 (31.4%) malignant. At surgical excision, 22 malignant lesions were found. The overall sensitivity, specificity, and positive and negative predictive values of MRI were 72.7% (16/22), 74.8% (110/147), 30.2% (16/53), and 94.8% (110/116). The negative predictive values for papilloma, radial scar, lobular neoplasia, and atypical ductal hyperplasia were 97.4% (38/39), 97.6% (41/42), 88.0% (22/25), and 90.0% (9/10)., Conclusion: Patients with high-risk lesions associated with the lowest likelihood of malignancy (papilloma and radial scar) and without suspicious MRI findings can safely undergo follow-up instead of surgery. Because of the low negative predictive value, however, MRI is not helpful in cases of lobular neoplasia and atypical ductal hyperplasia, and all these lesions should be excised.

Rationale and Objectives: Water molecule motion has been shown to be isotropic in healthy liver as assessed by diffusion-weighted imaging (DWI). The purpose of this study was to investigate whether this assumption is still valid in the cirrhotic liver., Materials and Methods: Twelve cirrhotic patients and 12 controls underwent DWI on a 3.0T-system. We used an echo-planar sequence independently applying unidirectional motion-probing gradients along read-(x), phase-(y), and slice-(z) directions, respectively. Liver apparent diffusion coefficient (ADC) and perfusion fraction (f) were calculated along each gradient direction, based on two b-values sets (0-400 and 0-800 seconds/mm(2)). Measurement was repeated at two different axial slices of the liver., Results: No significant difference among x, y, and z- ADC (and f) of the liver was found within controls and cirrhotic patients (P > .01), regardless of the set of b-values or the slice of measurement. ADC was lower in cirrhotic patients than in controls (difference of 0.24-0.39 × 10(-3) mm(2)/seconds at b = 800 seconds/mm(2); P = .000-.0139). Perfusion fraction f was lower in cirrhotics than in controls, irrespective of the b-values set or the slice of measurement (difference of 0.05-0.15; P < .0001-.0885)., Conclusion: The liver shows isotropic water diffusion in cirrhotics, despite fibrotic distortion leading to decreased ADC as compared to controls. Our results emphasize that the correlation between parenchymal changes in liver fibrosis and the ADC estimate remains an elusive goal based on the state-of-the-art DWI technique., (Copyright © 2012 AUR. Published by Elsevier Inc. All rights reserved.)

Purpose: This study was performed to assess the role of magnetic resonance cholangiography (MRC) in the clinical decision-making process of referring physicians when managing liver-transplanted patients., Materials and Methods: Over a 6-month period, 21 liver-transplanted patients with a suspected biliary complication were referred for MRC. Referring physicians were asked to prospectively state, before and after MRC, the leading diagnosis; the level of confidence (on a 0-100% scale); the most appropriate diagnostic/therapeutic plan. Data analysis assessed was the diagnostic yield of MRC; the proportion of change in the leading diagnosis; the therapeutic efficacy (i.e. proportion of change in the initial diagnostic/therapeutic plan); the diagnostic thinking efficacy (i.e., gain in diagnostic confidence). Statistical significance was assessed with the Mann-Whitney U test. MRC accuracy was also calculated., Results: Data analysis showed a diagnostic yield of 85.7%; a proportion of change in leading diagnosis of 19.0%; a therapeutic efficacy of 42.8%; a diagnostic thinking efficacy for concordant and discordant leading diagnoses of 18.8% and 78.7%, respectively (p<0.01). MRC accuracy was 92.3%., Conclusions: MRC significantly increased the diagnostic confidence, irrespective of the concordance between pre- and posttest diagnoses. Moreover, MRC determined a change in patient management in a significant proportion of cases, leading to clinical benefits.

Objectives: Comparing the sensitivity of Contrast-Enhanced Magnetic Resonance Imaging (CEMRI), mammography and ultrasonography in patients with nipple discharge (ND)., Methods: We retrospectively evaluated 38 women with ND who underwent mammography, ultrasound and 1.5 T CEMRI between March 2007 and July 2009. Imaging findings, pathological diagnosis and follow-up data (mean follow-up: 20 months) were compared. Sensitivity and specificity values were reckoned. Statistical differences in sensitivity were assessed., Results: 5/38 malignancies (13.2%; 3 invasive, 2 intraductal; 4 ipsilateral, 1 contralateral to ND), and 14/38 High-Risk Lesion (HRL--36.8%; 11 intraductal papillomas, 1 papilloma with LCIS, 1 sclerosing papilloma and 1 atypical intraductal hyperplasia, all ipsilateral) were found. CEMRI identified 5/5 cancers and 13/14 HRL (Overall Sensitivity-OSS = 94.7%; Overall Specificity-OSP = 78.9%). 3/5 cancers (1 invasive, 1 in-situ; 1 invasive contralateral) and 2/14 HRL were detected by CEMRI only. Mammography found 2/5 cancer and 3/14 HRL (OSS = 26.3%; OSP = 94.7%). Ultrasound identified 1/5 cancer and 11/14 HRL (OSS = 63.2%; OSP = 84.2). 1/14 HRL was detected by ultrasound only. Compared with mammography and ultrasound, CEMRI showed statistically significantly higher OSS values (p < 0.0001, p = 0.042 respectively)., Conclusion: In women with ND, CEMRI should be recommended when conventional imaging is negative. Unexplained ND could be considered an indication for CEMRI.

Objective: The purposes of our study were, first, to evaluate the frequency, clinical presentation, and associated imaging findings of malignant breast lesions presenting as hyperechoic nodules in a large series of consecutive sonographically guided core needle biopsies (CNBs) and, second, to investigate sonographic features that are able to predict malignancy in hyperechoic breast lesions., Materials and Methods: The radiologic and pathologic records for 4511 consecutive sonographically guided CNBs were retrospectively reviewed. Hyperechoic lesions were identified, and clinical notes and related mammography or MRI reports were reviewed. The sonographic images were evaluated according to the BI-RADS lexicon by two experienced breast radiologists. Surgical pathology results and follow-up served as the reference standard for lesions diagnosed as malignant or high-risk and benign at CNB, respectively. The frequency of hyperechoic carcinomas among all carcinomas was calculated. Differences in sonographic appearance between hyperechoic benign and malignant lesions were evaluated using the chi-square test or the Fisher exact test., Results: Of all biopsied lesions, 25 (0.6%) were hyperechoic. Among the 1849 malignant lesions, nine (0.4%) were hyperechoic. The remaining 16 were benign. None of the hyperechoic malignancies was a "purely" sonographic lesion, because all were palpable, mammographically visible, or detectable on breast MRI. Malignant lesions were more likely than benign lesions to have noncircumscribed margins (9/9 vs 7/16; p = 0.008) and nonparallel orientation (6/9 vs 1/16; p = 0.003)., Conclusion: When encountering a hyperechoic nodule, malignant nature cannot be excluded. Suspicious sonographic signs and correlation with other imaging techniques may help avoid misdiagnosis.

Purpose: To estimate the prevalence of incidental pancreatic cysts (IPCs) in asymptomatic patients addressed to magnetic resonance cholangiopancreatography (MRCP), and to correlate it with clinical and imaging features., Materials and Methods: Magnetic resonance cholangiopancreatography performed over 26-months on 152 patients with unsuspected/unknown pancreatic disease were reviewed to assess IPCs' features of presentation. Multivariate analysis was performed to evaluate the correlation of IPCs with clinical information and type of pancreaticobiliary findings at MRCP., Results: Prevalence of IPCs was 44.7%. Cysts sized 3-24 mm (mean, 6.08 mm), and were ≤4 in number in 83.8% of patients. Based on number, dimensions and relation with the main pancreatic duct, IPCs presented with intraductal-papillary-mucinous neoplasm (IPMN)-like or indeterminate patterns in 31.7% and 13.1% of patients, respectively. At follow-up on 24 patients, no evolution was found, except in one patient with proven IPMN showing increase in cysts number and dimensions (evolution rate of 4.1%). Features correlating with IPCs were age ≥60 years old, and history of autoimmune hepatobiliary disease, showing odds ratios of 5.95 (95% CI 2.77-12.79) and 0.13 (95% CI 0.04-0.44), respectively., Conclusions: Incidental pancreatic cysts represent a frequent finding at MRCP, correlating positively with increasing age, and negatively with biliary autoimmune disease. Cysts more frequently present with IPMN-like pattern.

Purpose: The authors evaluated the diagnostic yield of chest multidetector computed tomography (MDCT) in acute pulmonary embolism (PE) and the proportion of other clinically relevant findings in a large cohort of consecutive inpatients and patients referred from the emergency department (outpatients)., Materials and Methods: A total of 327 radiological reports of chest MDCT scans performed for suspected acute PE in 327 patients (158 men, 169 women; mean age 69 years, standard deviation 17.33 years; 233 inpatients, 94 outpatients) were retrospectively evaluated and classified into four categories: 1, positive for PE; 2, negative for PE but positive for other findings requiring specific and immediate intervention; 3, completely negative or positive for findings with a potential for significant morbidity requiring specific action on follow-up; 4, indeterminate. The distribution of findings by categories among the entire population and inpatients and outpatients separately was calculated (chi-square test, α=0.05)., Results: In the entire population, the diagnostic yield (i.e. proportion of cases classified as category 1) was 20.2% (66/327). Proportions of cases classified as categories 2, 3 and 4 were 27.5% (90/327), 44.3% (145/327) and 7.9% (26/327), respectively. No statistically significant difference was found between inpatients and outpatients (p=0.193)., Conclusions: In patients with suspected acute PE, chest MDCT provides evidence of conditions requiring immediate and specific intervention (i.e. categories 1 and 2) in nearly 50% of cases, without differences between inpatients and outpatients.

Purpose: To evaluate the accuracy of surgical specimen ultrasound in the assessment of the status of resection margins after breast-conserving surgery., Methods and Materials: Sonographic examination of 46 surgical specimens of US-detectable malignant tumors was performed. Distance of the lesion from the specimen margins in four radial directions was measured and compared with distances measured on pathologic examination. Positive pathologic margins were defined when invasive or intraductal carcinoma was found within 2 mm of the specimen margin. Sensitivity, specificity, positive(PPV) and negative predictive values(NPV) of US in predicting surgical margins were calculated, considering both a 10-mm and a 4-mm sonographic threshold., Results: Of 184 margins(4 per lesion), pathology demonstrated 28 positive and 156 negative margins. Considering the 10-mm cut-off, US identified 32 positive and 152 negative margins, showing the following sensitivity, specificity, PPV and NPV: 28.5%, 84.6%, 25% and 86.8%, respectively. Considering the 4-mm cut-off, US identified 7 positive and 177 negative margins, with a sensitivity of 7.1%, a specificity of 96.8%, a PPV of 28.2% and a NPV of 85.3%. False-negative results were more frequent in case of invasive lobular carcinoma (20%) and presence of intraductal component (60%)., Conclusion: Sonography demonstrated a poor performance in the evaluation of the status of resection margins in breast specimens; however, because of the high NPV -both with 10-mm and 4-mm thresholds- it might be helpful in confirming complete excision of a US-detected neoplasm and in ruling out the presence of macroscopic invasive ductal carcinoma at surgical margins., (Copyright © 2010. Published by Elsevier Ltd.)

Objective: To retrospectively compare portal venous phase (PVP) and delayed phase (DP) for the detection of tumor washout at gadobenate dimeglumine-enhanced liver magnetic resonance imaging (MRI) in cirrhotic patients with hypervascular hepatocellular carcinoma (HCC)., Methods: Thirty-three patients with 55 HCCs underwent 1.5-T MRI by means of fat-suppressed T1-weighted sequence obtained before and after gadobenate dimeglumine administration, during early and late arterial phases, PVP (70 seconds), and DP (180 seconds). Detection rates of contrast washout of hypervascular HCCs and tumor-to-liver contrast on PVP and DP were measured and compared., Results: Among 54 hypervascular HCCs, washout was present in 24 (44%) of 54 tumors on PVP and in 44 (82%) of 54 on DP (P < 0.001). In 20 (37%) of 54 tumors, washout was deemed present only on DP. Delayed phase images yielded significantly higher mean tumor-to-liver contrast absolute values compared with PVP images (-24.5 [56.1] vs -9.3 [52.6], P = 0.001)., Conclusions: Delayed phase is superior to PVP for the washout detection of hypervascular HCC at gadobenate dimeglumine-enhanced MRI of cirrhotic liver.

Unusual malignant breast tumors are well-differentiated subtypes of invasive ductal carcinoma, including mucinous, tubular, medullary and papillary carcinomas, and account for about 10% of malignant breast tumors. They are increasingly being encountered during magnetic resonance imaging (MRI) examinations of the breast. Therefore, breast radiologists should be aware of their appearance on MRI. This review provides an overview of MRI characteristics of a range of unusual tumors (mucinous carcinoma, medullary carcinoma, tubular carcinoma, intraductal papillary carcinoma, intracystic papillary carcinoma and invasive papillary carcinoma), highlighting specific clues for diagnosis and correlating MRI and pathologic features. Many unusual breast tumors exhibit MRI features similar to those of benign or low suspicious lesions (oval shape, well-defined margins, high signal intensity on T2-weighted images, continuous increase kinetics, i.e. type I dynamic curve), leading to a possible misdiagnosis. Nevertheless, an understanding of pathologic features of these tumors, especially tissue content (mucinous, fibrous) and growth pattern, can help to define some specific clues for their diagnosis., (Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.)

Objective: The purposes of our study were to evaluate the surgical outcome of cases of radial scar without atypia diagnosed at imaging-guided percutaneous needle biopsy and to determine whether the mammographic and sonographic features are able to predict which lesions will be upgraded to malignancy at surgical excision., Materials and Methods: The records of 4,458 consecutive imaging-guided biopsies were retrospectively reviewed. Surgical excision results were available in 62 cases in which radial scar was the highest-risk lesion at stereotactically guided or sonographically guided biopsy. The mammographic and sonographic images and surgical findings were reviewed. The underestimation rate of malignancy of percutaneous biopsy was calculated. Differences in mammographic and sonographic appearances between radial scars with and without associated malignancy were evaluated using the Fisher's exact test., Results: The percutaneous malignancy underestimation rate was 8% (5/62): 9% (4/43) for sonography guided 14-gauge biopsies and 5% (1/19) for stereotactically guided 11-gauge vacuum-assisted biopsies (p = 1.000). Mammographic and sonographic appearances were not significantly different between radial scars with and those without associated malignancy., Conclusion: A percutaneous diagnosis of a radial scar does not exclude associated malignancy at surgical excision. Mammographic and sonographic features of a lesion diagnosed as a radial scar at percutaneous imaging-guided biopsy do not predict which lesions will have associated malignancy at surgery. Therefore, all patients with percutaneous diagnosis of a radial scar should undergo surgical excision regardless of mammographic and sonographic appearances, until further criteria can be determined.

Post-cholecystectomy syndrome (PCS) is defined as a complex of heterogeneous symptoms, consisting of upper abdominal pain and dyspepsia, which recur and/or persist after cholecystectomy. Nevertheless, this term is inaccurate, as it encompasses biliary and non-biliary disorders, possibly unrelated to cholecystectomy. Biliary manifestations of PCS may occur early in the post-operative period, usually because of incomplete surgery (retained calculi in the cystic duct remnant or in the common bile duct) or operative complications, such as bile duct injury and/or bile leakage. A later onset is commonly caused by inflammatory scarring strictures involving the sphincter of Oddi or the common bile duct, recurrent calculi or biliary dyskinesia. The traditional imaging approach for PCS has involved ultrasound and/or CT followed by direct cholangiography, whereas manometry of the sphincter of Oddi and biliary scintigraphy have been reserved for cases of biliary dyskinesia. Because of its capability to provide non-invasive high-quality visualisation of the biliary tract, magnetic resonance cholangiopancreatography (MRCP) has been advocated as a reliable imaging tool for assessing patients with suspected PCS and for guiding management decisions. This paper illustrates the rationale for using MRCP, together with the main MRCP biliary findings and diagnostic pitfalls.

Purpose: Chest radiography (CXR) of immunocompromised patients has low sensitivity in the early evaluation of pulmonary abnormalities suspected to be infectious. The purpose of the study was to evaluate whether the knowledge of clinical data improves the diagnostic sensitivity of CXR in the particular setting of immunocompromised patients after hematopoietic stem cell transplantation (HSCT)., Materials and Methods: Sixty-four CXRs of immunocompromised patients with clinically suspected pneumonia were retrospectively and independently evaluated by two radiologists to assess the presence of radiological signs of pneumonia, before (first reading) and after (second reading) the knowledge of clinical data. A chest computed tomography (CT) performed within 3 days was assumed as the standard of reference. For each reading, sensitivity of both radiologists was calculated., Results: Readers showed a sensitivity of 39% and 58.5% for the first reading, and 43.9% and 41.5% for the second reading, respectively. For both readers, these values were not significantly different from those obtained at first reading (McNemar's test, p>0.05). Interobserver agreement at second reading was fair (Cohen test, k=0.33)., Conclusions: The sensitivity of CXR is too low to consider it a stand-alone technique for the evaluation of immunocompromised patients after HSCT with suspected pneumonia, even if the radiologist knows detailed clinical data. For these patients, an early chest CT evaluation is therefore recommended.

Context: The increasing frequency of incidental pancreatic cysts at imaging is a challenging topic due to the uncertainty of the aggressiveness of these lesions, especially small ones. To date, no data exist about their prevalence in a population of liver-transplanted patients., Objective: To determine the prevalence of incidental pancreatic cysts in liver-transplanted patients using magnetic resonance cholangiopancreatography., Design: A retrospective, single center case series., Setting: A tertiary referral centre. Interventions and patients Seventy-two examinations were performed over a two-year period in 47 liver-transplanted patients suspected for biliary complications., Main Outcome Measures: Prevalence of incidental pancreatic cysts; proportion of cyst evolution over time; association of cysts with clinical and imaging features., Results: The prevalence of pancreatic cysts was 59.6%. Analysis showed a mean diameter of 5.4 mm and the presence of 1-3 cysts in 78.6% of patients (22/28). Communication with the main pancreatic duct was identified for 28 relatively larger cysts (up to 14 mm) in 14 subjects. An "intraductal papillary mucinous neoplasia-like pattern" was observed in 12 patients with cysts, based on the number of cysts, dimensions, and distribution. Out of the 15 patients who underwent additional MRCPs to monitor biliary findings, only one patient with proven intraductal papillary mucinous neoplasia showed modification of the cysts at follow-up. Among the evaluated pre- or post-transplantation factors (sex, age, etiology of cirrhosis, pre-transplant hepatocarcinoma, pancreatic abnormalities other than cysts, type of pancreaticobiliary channel/biliary anastomosis, presence of biliary complications, lithiasic biliary complications, transplant-examination interval), only the alcoholic etiology of cirrhosis was associated with the prevalence of pancreatic cysts (P=0.006)., Conclusions: Incidental pancreatic cysts are frequent in liver-transplanted patients. Clinical significance, relation to transplant, impact on patient management before and after transplant are still under debate and a matter for further investigation.

Crohn's disease often leads to stricture formation, occlusion and surgery. Unfortunately the disease tends to recur often. Traditional medications seem very little effective for recurrence prevention. By contrast, biologics appear extremely promising and potentially capable of changing radically the management of this disease.

The clinical use of breast magnetic resonance (MR) imaging is increasing, especially for applications requiring paramagnetic contrast-agent injection. This document presents a synthetic list of acceptable indications with potential advantages for women according to evidence from the literature and the expert opinion of the panel that developed this statement. We generally recommend that breast MR imaging be performed in centres with experience in conventional breast imaging [mammography and ultrasonography (US)] and needle-biopsy procedures (under stereotactic or US guidance) as well as in breast MR imaging and second-look US for findings not revealed by conventional imaging performed before MR imaging. In our opinion, there is no evidence in favour of breast MR imaging as a diagnostic tool to characterise equivocal findings at conventional imaging when needle-biopsy procedures can be performed, nor for the study of asymptomatic, non-high-risk women with negative conventional imaging. After a description of technical and methodological requirements, we define the indications and limitations of breast MR imaging for surveillance of high-risk women, local staging before surgery, evaluation of the effect of neoadjuvant chemotherapy, breast previously treated for carcinoma, carcinoma of unknown primary syndrome, nipple discharge and breast implants.

Orthotopic liver transplantation is a widely accepted treatment for end-stage liver disease and selected cases of hepatocellular carcinoma. Despite surgical progresses, biliary complications after transplantation remain a serious cause of morbidity, mortality, and graft dysfunction or failure in recipients. Early complications occur within a few weeks after transplantation and are mainly represented by bile leakage. Late complications, which become evident from 3 months to years, include strictures, stones, intraductal debris or sludge formation, kinking and ampullary dysfunction. Donor-to-recipient common bile duct disproportion has been reported as a borderline condition. Diagnosis is challenging because of the low specificity of clinical and biologic findings. Sonography does not provide projectional images of the biliary tract or direct evaluation of the anastomoses. Moreover, direct cholangiographic procedures have an unacceptable rate of complications to be used in patients with low clinical suspicion. Magnetic resonance cholangiography is a safe and accurate tool, playing an increasing role in the diagnosis and management of biliary complications. Heavily T2-weighted images provide panoramic, detailed evaluation of the biliary tract, showing biliary complications as a variable combination of bile duct dilatation, strictures, filling defects, fluid collections and peculiar morphologic changes, as described in this paper.

Purpose: To investigate the relevance of increasing b-values in evaluating liver fibrosis through the agreement of two diffusion-weighted (DW) sequences., Materials and Methods: A total of 29 cirrhotic patients and 29 healthy volunteers were studied on a 1.5T system. Two single-shot spin-echo echo-planar sequences were acquired using sets of increasing b-values: 0, 150, 250, and 400 seconds/mm(2) (first sequence: DW1a) and 0, 150, 250, 400, 600, and 800 seconds/mm(2) (second sequence: DW2a). Apparent diffusion coefficients (ADCs) of the hepatic parenchyma were calculated on ADC maps. Noise-scaled single-point ADCs were calculated for each sequence from b = 400 seconds/mm(2)., Results: ADCs resulted significantly lower in cirrhotic patients compared to controls using both DW1a (mean 1.14 +/- 0.20 x 10(-3)mm(2)/second vs. 1.54 +/- 0.12 x 10(-3)mm(2)/second; P < 0.0001) and DW2a (mean 0.91 +/- 0.18 x 10(-3)mm(2)/second vs. 1.04 +/- 0.18 x 10(-3)mm(2)/second; P = 0.0089). DW1 and DW2, respectively significantly differed in diagnostic performance at receiver operating characteristic (ROC) curve analysis (P = 0.003), showing AUCs of 0.93 (sensitivity 89.7%, specificity 100%) and 0.73 (sensitivity 62.1%, specificity 79.3%), respectively. Noise-scaled single-point ADCs showed a progressive convergence to similar values in cirrhotic and healthy livers at b = 800 seconds/mm(2) (1.12 +/- 0.27 x 10(-3)mm(2)/second vs. 1.13 +/- 0.17 x 10(-3)mm(2)/second)., Conclusion: A DW sequence is accurate in assessing liver fibrosis using intermediate (400 seconds/mm(2)) rather than high (800 seconds/mm(2)) maximum b-values, but after proper recalculation of ADCs the effects of perfusion rather than diffusion should be considered responsible for the higher accuracy at lower b-values., ((c) 2008 Wiley-Liss, Inc.)

Rationale and Objectives: We sought to investigate the value of a MRI scoring system including dynamic motility evaluation in the assessment of small bowel Crohn's disease activity., Materials and Methods: From March 2005 to December 2006, 52 patients with suspected Crohn's disease onset or relapse underwent MRI on a 1.5-T magnet. Bowel distention was achieved orally assuming a mean of 1.6 L of a polyethyleneglycol (PEG) preparation. Per-patient assessment of disease activity was based on a scoring system including evaluation of morphology and motility of the small bowel and perivisceral structures (true-FISP, cine-true-FISP, and HASTE T2W sequences) and dynamic assessment of parietal contrast enhancement (FLASH T1W sequence). Patients were included in three categories, using endoscopic biopsy as the standard reference: no activity/quiescent disease, mild activity, or moderate-to-severe activity. Patients without terminal ileum involvement were excluded from data analysis., Results: MRI allowed a detailed and panoramic evaluation of the small bowel in all subjects examined. MRI properly assessed 14 of 16 (87.5%) cases of no activity/quiescent disease, 12 of 14 (85.7%) cases of mild activity, and 15 of 15 (100%) cases of severe activity. Overall, activity score led to a per-patient misdiagnosis of disease activity in a nonsignificant proportion of subjects (4 of 45; 8.8%) (P > .05), determining two false-positive and two false-negative results of mild disease activity. Sensitivity, specificity, PPV, NPV, and overall accuracy in assessing disease activity were 93.1%, 87.5%, 93.1%, 87.5%, and 91.1%, respectively., Conclusion: Accurate assessment of Crohn's disease activity is achieved by using an activity score providing an overall interpretation of MRI findings.

Purpose: This study was designed to establish whether the measurement of apparent diffusion coefficients (ADCs) is clinically accurate in diagnosing liver fibrosis in a selected series of cirrhotic patients., Materials and Methods: Twenty-eight cirrhotic patients (mean age 58.1 years) with histologically proven liver fibrosis and 29 healthy controls (mean age 43.8 years) underwent liver diffusion-weighted magnetic resonance (MR) using a 1.5-Tesla (T) magnet equipped with a phased-array coil. Diffusion studies with parallel imaging [generalized autocalibrating partially parallel acquisitions (GRAPPA)] were performed within a single breath-hold using a single-shot spin-echo echo-planar sequence (TE 74 ms) using four b values: b=0, 150, 250 and 400 s/mm(2). A unidirectional diffusion gradient was applied. ADCs were measured on ADC maps., Results: Mean ADC was significantly lower in cirrhotic livers than in controls (1.11+/-0.16 vs. 1.54+/-0.12.10(-3)mm(2)/s) (p<0.0001). Receiver operating characteristic (ROC) analysis showed an area under the curve (AUC) of 0.96 [confidence interval (CI) 95%:(0.87; 0.94)], demonstrating higher sensitivity and specificity (92.9% and 100%, respectively) for an ADC cutoff of 1.31.10(-3)mm(2)/s. Positive predictive value (PPV), negative predictive value (NPV) and overall accuracy were 100%, 99.9% and 96.4%, respectively., Conclusions: Diffusion-weighted MRI is an accurate tool in evaluating advanced liver fibrosis if an optimised single-shot spin-echo echo-planar sequence with maximum intermediate b value is used. The ADC threshold for liver fibrosis was 1.31.10(-3)mm(2)/s.

The introduction of systems for automated reading in mammography has been proposed to improve the sensitivity [computer-aided detection (CADe) systems] and, more recently, the specificity [computer-aided diagnosis (CADi) systems] of the test. Only CADe systems have been approved by the U.S. Food and Drug Administration (FDA) and are used in current practice. These systems are still under discussion. Several studies have demonstrated that they are beneficial to inexperienced readers and that, through comparison with the computer, radiologists are led to improve their performance. However, there is still considerable variation among different studies in the level of benefit deriving from CAD. Therefore the role of these systems in clinical practice is still debated, and their real contribution to the overall management of the diagnostic process is not yet clear.