Search

Purpose: To explore the variation of the discriminative power of CT (Computed Tomography) radiomic features (RF) against image discretization/interpolation in predicting early distant relapses (EDR) after upfront surgery., Materials and Methods: Data of 144 patients with pre-surgical high contrast CT were processed consistently with IBSI (Image Biomarker Standardization Initiative) guidelines. Image interpolation/discretization parameters were intentionally changed, including cubic voxel size (0.21-27 mm 3 ) and binning (32-128 grey levels) in a 15 parameter's sets. After excluding RF with poor inter-observer delineation agreement (ICC < 0.80) and not negligible inter-scanner variability, the variation of 80 RF against discretization/interpolation was first quantified. Then, their ability in classifying patients with early distant relapses (EDR, < 10 months, previously assessed at the first quartile value of time-to-relapse) was investigated in terms of AUC (Area Under Curve) variation for those RF significantly associated to EDR., Results: Despite RF variability against discretization/interpolation parameters was large and only 30/80 RF showed %COV < 20 (%COV = 100*STDEV/MEAN), AUC changes were relatively limited: for 30 RF significantly associated with EDR (AUC values around 0.60-0.70), the mean values of SD of AUC variability and AUC range were 0.02 and 0.05 respectively. AUC ranges were between 0.00 and 0.11, with values ≤ 0.05 in 16/30 RF. These variations were further reduced when excluding the extreme values of 32 and 128 for grey levels (Average AUC range 0.04, with values between 0.00 and 0.08)., Conclusions: The discriminative power of CT RF in the prediction of EDR after upfront surgery for pancreatic cancer is relatively invariant against image interpolation/discretization within a large range of voxel sizes and binning., (© 2023. Italian Society of Medical Radiology.)

Purpose: To determine the clinical, pathological, and radiological features, including the Vesical Imaging-Reporting and Data System (VI-RADS) score, independently correlating with muscle-invasive bladder cancer (BCa), in a multicentric national setting., Method and Materials: Patients with BCa suspicion were offered magnetic resonance imaging (MRI) before trans-urethral resection of bladder tumor (TURBT). According to VI-RADS, a cutoff of ≥ 3 or ≥ 4 was assumed to define muscle-invasive bladder cancer (MIBC). Trans-urethral resection of the tumor (TURBT) and/or cystectomy reports were compared with preoperative VI-RADS scores to assess accuracy of MRI for discriminating between non-muscle-invasive versus MIBC. Performance was assessed by ROC curve analysis. Two univariable and multivariable logistic regression models were implemented including clinical, pathological, radiological data, and VI-RADS categories to determine the variables with an independent effect on MIBC., Results: A final cohort of 139 patients was enrolled (median age 70 [IQR: 64, 76.5]). MRI showed sensitivity, specificity, PPV, NPV, and accuracy for MIBC diagnosis ranging from 83-93%, 80-92%, 67-81%, 93-96%, and 84-89% for the more experienced readers. The area under the curve (AUC) was 0.95 (0.91-0.99). In the multivariable logistic regression model, the VI-RADS score, using both a cutoff of 3 and 4 (P < .0001), hematuria (P = .007), tumor size (P = .013), and concomitant hydronephrosis (P = .027) were the variables correlating with a bladder cancer staged as ≥ T2. The inter-reader agreement was substantial (k = 0.814)., Conclusions: VI-RADS assessment scoring proved to be an independent predictor of muscle-invasiveness, which might implicate a shift toward a more aggressive selection approach of patients' at high risk of MIBC, according to a novel proposed predictive pathway., (© 2022. The Author(s).)

Purpose: To assess the ability of radiomic features (RF) extracted from contrast-enhanced CT images (ceCT) and non-contrast-enhanced (non-ceCT) in discriminating histopathologic characteristics of pancreatic neuroendocrine tumors (panNET)., Methods: panNET contours were delineated on pre-surgical ceCT and non-ceCT. First- second- and higher-order RF (adjusted to eliminate redundancy) were extracted and correlated with histological panNET grade (G1 vs G2/G3), metastasis, lymph node invasion, microscopic vascular infiltration. Mann-Whitney with Bonferroni corrected p values assessed differences. Discriminative power of significant RF was calculated for each of the end-points. The performance of conventional-imaged-based-parameters was also compared to RF., Results: Thirty-nine patients were included (mean age 55-years-old; 24 male). Mean diameters of the lesions were 24 × 27 mm. Sixty-nine RF were considered. Sphericity could discriminate high grade tumors (AUC = 0.79, p = 0.002). Tumor volume (AUC = 0.79, p = 0.003) and several non-ceCT and ceCT RF were able to identify microscopic vascular infiltration: voxel-alignment, neighborhood intensity-difference and intensity-size-zone families (AUC ≥ 0.75, p < 0.001); voxel-alignment, intensity-size-zone and co-occurrence families (AUC ≥ 0.78, p ≤ 0.002), respectively). Non-ceCT neighborhood-intensity-difference (AUC = 0.75, p = 0.009) and ceCT intensity-size-zone (AUC = 0.73, p = 0.014) identified lymph nodal invasion; several non-ceCT and ceCT voxel-alignment family features were discriminative for metastasis (p < 0.01, AUC = 0.80-0.85). Conventional CT 'necrosis' could discriminate for microscopic vascular invasion (AUC = 0.76, p = 0.004) and 'arterial vascular invasion' for microscopic metastasis (AUC = 0.86, p = 0.001). No conventional-imaged-based-parameter was significantly associated with grade and lymph node invasion., Conclusions: Radiomic features can discriminate histopathology of panNET, suggesting a role of radiomics as a non-invasive tool for tumor characterization., Trial Registration Number: NCT03967951, 30/05/2019.

Purpose: In overwhelmed emergency departments (EDs) facing COVID-19 outbreak, a swift diagnosis is imperative. CT role was widely debated for its limited specificity. Here we report the diagnostic role of CT in two EDs in Lombardy, epicenter of Italian outbreak., Material and Methods: Admitting chest CT from 142 consecutive patients with suspected COVID-19 were retrospectively analyzed. CT scans were classified in "highly likely," "likely," and "unlikely" COVID-19 pneumonia according to the presence of typical, indeterminate, and atypical findings, or "negative" in the absence of findings, or "alternative diagnosis" when a different diagnosis was found. Nasopharyngeal swab results, turnaround time, and time to positive results were collected. CT diagnostic performances were assessed considering RT-PCR as reference standard., Results: Most of cases (96/142, 68%) were classified as "highly likely" COVID-19 pneumonia. Ten (7%) and seven (5%) patients were classified as "likely" and "unlikely" COVID-19 pneumonia, respectively. In 21 (15%) patients a differential diagnosis was provided, including typical pneumonia, pulmonary edema, neoplasia, and pulmonary embolism. CT was negative in 8/142 (6%) patients. Mean turnaround time for the first COVID-19 RT-PCR was 30 ± 13 h. CT diagnostic accuracy in respect of the first test swab was 79% and increased to 91.5% after repeated swabs and/or BAL, for 18 false-negative first swab. CT performance was good with 76% specificity, 99% sensitivity, 90% positive predictive value and 97% negative predictive value., Conclusion: Chest CT was useful to streamline patients' triage while waiting for RT-PCR in the ED, supporting the clinical suspicion of COVID-19 or providing alternative diagnosis.

Cardiac magnetic resonance (CMR) has emerged as new mainstream technique for the evaluation of patients with cardiac diseases, providing unique information to support clinical decision-making. This document has been developed by a joined group of experts of the Italian Society of Cardiology and Italian society of Radiology and aims to produce an updated consensus statement about the current state of technology and clinical applications of CMR. The writing committee consisted of members and experts of both societies who worked jointly to develop a more integrated approach in the field of cardiac radiology. Part 1 of the document will cover ischemic heart disease, congenital heart disease, cardio-oncology, cardiac masses and heart transplant.

Cardiovascular diseases are still among the first causes of death worldwide with a huge impact on healthcare systems. Within these conditions, the correct diagnosis of coronary artery disease with the most appropriate imaging-based evaluations is of utmost importance. The sustainability of the healthcare systems, considering the high economic burden of modern cardiac imaging equipments, makes cost-effective analysis an important tool, currently used for weighing different costs and health outcomes, when policy makers have to allocate funds and to prioritize interventions, getting the most out of their financial resources. This review aims at evaluating cost-effective analysis in the more recent literature, focused on the role of Calcium Score, coronary computed tomography angiography and cardiac magnetic resonance.

Background: Cardiac CT with late iodine enhancement (LIE-CT) may characterize the scarred myocardium, but the role of readers' experience and scar pattern on LIE-CT diagnostic performance is unknown. Aim was to assess the diagnostic performance of LIE-CT according to readers' experience, scar pattern and contrast-to-noise ratio (CNR) using late gadolinium enhancement MRI (LGE-MRI) as reference., Methods: LIE-CT and LGE-MRI images of 40 consecutive patients were analyzed. Two readers with different experience (8 and 2 years) independently analyzed LIE-CT images defining the presence/absence of scar and scar CNR, segmental involvement, transmural pattern and scar etiology. The same parameters were extracted from LGE-MRI by two expert readers in consensus, blinded to the LIE-CT results., Results: Scars were identified at LGE-MRI in 29/40 patients and 141/680 segments. Scar burden at LIE-CT versus LGE-MRI correlated better for the most experienced reader than for the least experienced one (ρ = 0.954 and ρ = 0.797, p < 0.001). The most experienced reader missed scars in 2 patients and in 21/141 segments; the least experienced in 5 patients and 53/141 segments. The most experienced reader showed higher accuracy and sensitivity compared to the least experienced in per-patient (accuracy: 95% vs. 88%; sensitivity: 93% vs. 83%) and per-segment analysis (accuracy: 96% vs. 92%; sensitivity: 85% vs. 62%). Specificity was excellent (100% per-patient, 99% per-segment,) regardless of readers' experience. Missed scars had non-ischemic pattern, low scar burden (< 6%) and lower CNR compared to ischemic scars (2.33 vs. 3.54, p = 0.005)., Conclusion: LIE-CT represents an alternative to LGE-MRI, although the impact of readers' experience on sensitivity for small non-ischemic scars should be considered.

Interventional radiology provides local management of bone metastases (BM) with a palliative intent in most cases, or with a curative intent in selected patients. Its role has rapidly expanded in the last decade, offering new treatment solutions often in combination with surgery, radiation therapy and medical treatments. The aim of the present paper is to increase awareness, acceptance and adoption of interventional radiology procedures for the treatment of BM; and to present the joint position of the Italian College of Musculoskeletal Radiology and the Italian College of Interventional Radiology.

Purpose: To investigate the role of orbital color Doppler ultrasound (OCDUS) in the diagnosis of carotid-cavernous fistula (CCF) with anterior drainage and particularly whether a negative OCDUS could avoid an invasive diagnostic cerebral angiography (DSA)., Materials and Methods: Twenty-two consecutive patients with ophthalmic signs suspecting CCF were submitted to ophthalmologic examination, OCDUS and DSA. CCF diagnosis with OCDUS was based on the finding of a reversed, arterialized and low-resistive-index (RI <0.5) blood flow in the superior ophthalmic vein (SOV). Sensibility, specificity, PPV, NPV, and accuracy of OCDUS were calculated considering both patients and eyes, using DSA as gold standard., Results: DSA demonstrated 20 CCFs in 18 patients. Considering the patients, in 18/22 CCF diagnosis was positive at OCDUS and DSA while 4/22 were negative at both. Considering the eyes, in 24/43 CCF diagnosis was positive at both DSA and OCDUS (total eyes = 43, due to one case of SOV thrombosis). In 19/43 eyes diagnosis was negative at both OCDUS and DSA. So sensitivity, specificity, PPV, NPV, and accuracy of OCDUS in the patients and eyes analysis were all 100 %., Conclusions: OCDUS is a reliable, noninvasive tool in the diagnosis of CCF; a negative OCDUS could avoid an invasive DSA in patients suspected for anterior-draining CCF.

Purpose: To investigate the role of the apparent diffusion coefficient (ADC) as a potential prognostic biomarker in the evaluation of the aggressiveness of oesophageal cancer., Materials and Methods: Between November 2009 and December 2013, 43 patients with evidence of oesophageal or oesophago-gastric junction cancer were referred to our institution and prospectively entered in our database. The final study population consisted of 23 patients (18 men; 5 women; mean age, 64.62 ± 10.91 years) who underwent diffusion-weighted Magnetic Resonance before surgical intervention. Specifically, 14 were directly treated with surgery and 9 were addressed to chemo/radiotherapy beforehand. Two radiologists independently measured mean tumour ADC and inter-observer agreement (Spearman's and intraclass correlation coefficient [ICC]) was assessed. In the univariate analysis, overall survival curves related to pathological ADC, pT, pN, tumour location and histotype were fitted using the Kaplan-Meier method. Survival curves were then compared using the log-rank test., Results: Inter-observer reproducibility was very good (Spearman's rho = 0.95; ICC = 0.94). At a total median follow-up of 19 months (2-49 months), 4 patients had died. The median follow-up was 18.50 months (5-49 months) for the surgery-only group (1/4 events, 25 %) and 24 months (2-34 months) for the chemo/radiotherapy group (3/4 events, 75 %). Survival time at 48 months for the overall population was 59 % (±0.11), while for the surgery-only group and the chemo/radiotherapy group was 90 % (±0.09) and 61 % (±0.34), respectively. In the univariate analysis, ADC values below or equal to 1.4 × 10(-3) mm(2)/s were associated with a negative prognosis both in the total population (P = 0.016) and in the surgery-only group (P < 0.001)., Conclusion: Despite the biggest limitation of our study (i.e. the small study population), we were able to show that pathological ADC could be considered a prognostic factor for oesophageal cancer. DWI might be introduced into clinical practice as a promising and reliable technique in the diagnostic pathway of this tumour.

Purpose: To establish the appropriate number of Cardiac-CT and Cardio-MR examinations, to determine an economically justified and sustainable investment in these two technologies, for an exclusive cardiologic use., Materials and Methods: From July 2013 to July 2014, through a survey in four different Italian Departments of Radiology, data on the costs of Cardiac-CT and Cardiac-MR examinations were collected. For the evaluation of the costs of examinations, it was used an analytical accounting system, considering only the direct costs (consumables, health personnel work time, equipment amortization/maintenance) and other costs (utilities, services, etc.). Indirect costs (general costs) were not assessed. It was made a simulation, assuming an exclusive use of the CT and MR equipments for Cardiac-CT and Cardiac-MR examinations, calculating the annual number necessary to arrive at the Break Even Point (BEP: the point at which cost or expenses and revenue are equal)., Results: On the basis of the CT costs, in order to reach the BEP, performing only Cardiac-CT examinations, an average of 2641-2752 examinations/year is needed. The annual time commitment of the Medical Professional to ensure the number of examinations to reach the BEP is 2625-2750 h/year, equivalent to two Medical Doctors in a Cardiology Department. The recent Cardiac-CT Italian Registry, in the period January-June 2011, reports a number of examinations of 3455 patients in 47 different Centers, distributed throughout the whole national territory. With regard to MR, in order to reach the BEP, performing only Cardiac-MR examinations, an average of 2435-3123 examinations/year is needed. The annual time commitment of the Medical Professional to ensure the number of examinations to reach the BEP is 2437-3125 h/year, equivalent to two Medical Doctors in a Cardiology Department. The recent Cardiac-MR Italian Registry reports a number of examinations of 3776 patients in 40 Centers, distributed throughout the whole national territory., Conclusion: This research has shown that, only on the basis of costs, currently in Italy is anti-economic an exclusive use of CT or MR equipment for cardiac exams, unless it's not decided, regardless of the recent guidelines and clinical indications, to submit all patients with cardiac diseases (diseases of the coronary arteries and cardiomyopathies) to Cardiac-CT and Cardiac-MR examinations. This might likely to increase both the inappropriate examinations and either health spending and in the case of CT with important repercussions, in terms of radio-exposure, subject to forensic procedures.

Purpose: The authors prospectively compared single dose (0.1 mmol/kg bodyweight) gadobenate dimeglumine with double dose (0.2 mmol/kg bodyweight) gadopentetate dimeglumine for contrast-enhanced magnetic resonance angiography (CE-MRA) in patients with suspected or known steno-occlusive disease of the carotid, renal or peripheral vasculature using an intra-individual crossover study design., Materials and Methods: Twenty-eight patients with suspected or known steno-occlusive disease of the carotid (n = 16), renal (n = 5) or peripheral arteries (n = 7) were randomised to receive either 0.1 mmol/kg gadobenate dimeglumine or 0.2 mmol/kg gadopentetate dimeglumine for a first CE-MRA procedure. After 3-5 days all patients underwent a second identical CE-MRA procedure with the other contrast agent. Three blinded readers assessed images for vessel anatomical delineation, disease detection/exclusion, and global preference. Diagnostic performance for detection of ≥51 % stenosis was determined for 20/28 patients who also underwent digital subtraction angiography (DSA). Non-inferiority was assessed using the Wilcoxon signed rank, McNemar and Wald tests. Quantitative (signal-to-noise and contrast-to-noise ratio) enhancement based on 3D maximum intensity projection reconstructions was compared., Results: No differences were noted for any qualitative parameter. Equivalence was reported for all diagnostic preference end-points. Superiority for gadobenate dimeglumine was reported by all readers for sensitivity for disease detection (80.8-86.5 vs. 75.0-82.7 %). Quantitative enhancement was similar for single dose gadobenate dimeglumine and double dose gadopentetate dimeglumine., Conclusions: Under identical examination conditions a single 0.1 mmol/kg body weight dose of gadobenate dimeglumine can fully replace a double 0.2 mmol/kg body weight dose of gadopentetate dimeglumine for routine CE-MRA procedures.

Purpose: This study investigated the clinical application of a magnetic-resonance (MR)-guided breast biopsy (MRBB) system consisting of a nonmagnetic coaxial needle and a ferromagnetic core biopsy needle., Materials and Methods: MRBB was performed on 70 breast lesions. The biopsy device consisted of a nonmagnetic 14- to 16-gauge coaxial needle and a ferromagnetic 16- to 18-gauge biopsy needle., Results: Of the 70 lesions, 29 were malignant and 41 nonmalignant. All 29 malignant lesions underwent surgery and were confirmed as malignant at final histology. Of the 41 nonmalignant lesions, 35 underwent follow-up breast MR imaging (mean, 26 ± 19 months), which demonstrated no lesions changes; six lesions underwent surgery because of poor radiological-pathological correlation; of these 6 lesions, 3 were nonmalignant, one was borderline (lobular carcinoma in situ) and two were malignant (well-differentiated tubular carcinoma and infiltrating ductal carcinoma). Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy were, respectively, 93.5%, 100%, 100%, 95.1% and 97.1% if the lobular carcinoma in situ was considered a nonmalignant histological result, and 90.6%, 100%, 100%, 92.7% and 95.7% if the lobular carcinoma in situ was considered malignant., Conclusions: MRBB with a ferromagnetic-nonmagnetic coaxial system represented an easy way to perform a biopsy procedure and was easily applicable in the routine clinical setting.

Aim: To assess the feasibility and accuracy of cytologic and microhistologic breast biopsy using a MR imaging-guided stereotactic system with MR-compatible non-magnetic needles., Materials and Methods: Between December 2001 and September 2002, cytologic and microhistologic sampling of 14 lesions (12 patients) was performed in our radiology department using a commercially available MR-guided stereotactic device. MR-compatible non-magnetic needles or mixed kit (non-magnetic coaxial needle + conventional ferromagnetic needle) were used. Of the 12 patients examined, 2 were undergoing MR examination because of genetic/familial risk, 4 during post-operative follow-up and the remaining 6 for contradictory mammographic and sonographic findings. Ten of the 14 lesions were visible on MR alone. The mean lesion diameter was 12 mm (range 5-30 mm)., Results: The procedure was relatively simple and feasible. The procedure took 45 minutes on average. The cytologic samples were adequate in 4/14 cases (29%). The diagnosis was absence of malignant cells in one case, ductal carcinoma in one case and suspected carcinoma in two cases. The cytologic diagnosis was confirmed by core biopsy, and by post-operative histology in the malignant lesions. The remaining 10/14 (71%) cytologic samples were inadequate for diagnosis. All the microhistologic samples (100%) were considered sufficient for diagnosis and yielded diagnosis of benignity in 9/14 (60%) lesions and malignancy in 5/14 (40%). Two patients with benign diagnosis underwent surgery, which confirmed the diagnosis. The remaining seven patients were evaluated by follow-up MRI; the first follow-up at 3 months showed no significant changes. Post-operative histology of the 5 lesions with malignant microhistologic diagnosis confirmed the nature of the lesions., Conclusions: MR-guided stereotactic biopsy is a simple, fast and safe procedure comparable to the interventional breast procedures performed under mammography and ultrasound guidance. The stereotactic device used ensures correct positioning of the needle into the lesion. The new dedicated non-magnetic needles and the mixed kit provide quantitatively and qualitatively adequate tissue for the histologic analysis. On the basis of our initial experience, we conclude that the procedure is feasible and accurate and can therefore be recommended for routine clinical use.

The aim of this work is to describe the characteristics of Magnetic Resonance contrast media available or experimental in evaluation of focal liver diseases: non specific extracellular contrast media, reticoloendothelial and hepatobiliary-specific contrast media. A rational use of these different categories is suggested by analysis of their molecular and pharmacokinetic features.

Introduction: Cardiovascular disease remains the leading cause of death in the world. Invasive coronary angiography is currently the only clinical method available to visualize the coronary arteries, with up to 20% of the procedures demonstrating no evidence of severe coronary artery stenoses. We investigated the role of two-dimensional (2D) coronary magnetic resonance angiography (MRA) in patients with suspected coronary arteries disease and to check the placement and the patency of previously placed coronary artery stents., Material and Methods: Eleven patients with suspected coronary artery disease who underwent elective cardiac catheterization with coronary angiography were examined with 2D coronary MRA to detect coronary artery stenoses. Other 11 patients with 13 stented coronary arteries (6 RCA, 5 LAD, 2 Lcx) were prospectively examined with MRA one day to 8 months after stent placement. Eighteen amagnetic stents were imaged. Imaging was performed with a 1.5 T MR unit (GE Signa Horizon Echo Speed) with a phased array multicoil. Segmented k-space fast GE sequences were acquired with and without fat suppression at several cardiac cycle phases within a single breath-hold. Correlation with coronary angiography was performed in all patients., Results: Thirteen significant stenoses were found at coronary angiography in 11 coronary arteries. The sensitivity and specificity of MR coronary angiography, as compared with conventional angiography, in correctly identifying the single vessels with > 50% angiographic stenoses were 73% and 94%, respectively. The corresponding positive and negative predictive values and accuracy were 88%; 84% and 86%, respectively. As far as the study of coronary artery stents is concerned, no MR-related adverse events were observed. The stents were visualized as signal loss areas. The length of the signal loss corresponded to the length of the stents in all 18 cases (r = 97). The patent blood flow distal to the stents appeared as a high-signal band distal to the signal void, corresponding to stent patency at coronary angiography., Conclusions: Although in an early stage of technical development, 2D coronary MRA can depict 73% of hemodynamically severe coronary artery stenoses. Moreover breath-hold coronary cine MRA is a safe technique to visualize coronary artery stents. Stent site and patency can be noninvasively studied with this technique.

The purpose of this study was to assess Magnetic Resonance Imaging (MRI) patterns of hepatocellular carcinoma (HCC) treated with percutaneous ethanol injection (PEI) or Transarterial Chemoembolization (TACE) and, consequently, the potential role of MR Imaging in the follow-up of these lesions. HCC treated with PEI. Thirty-one patients with a single small HCC lesion underwent MR Imaging at 0.5 T before and after PEI. In all cases before and after treatment contrast enhanced Computed Tomography (CT) and US-guided fine-needle biopsy were performed. Twenty-seven of 31 HCC lesions in which complete tumor necrosis was obtained with PEI showed homogeneous hypointensity on SE T2-weighted MR images. This feature corresponded to an unenhanced and low-attenuation area on follow-up contrast-enhanced CT scans. All these lesions were negative for malignant cells at fine-needle biopsy follow-up. In four HCCs, high-signal areas on SE T2-weighted images and high-attenuation areas on contrast-enhanced CT scans were observed, suggesting the presence of residual tumor tissue; these lesions were positive for malignant cells at 6-month fine-needle biopsy. In each case, incomplete tumor necrosis was confirmed at pathologic examination of the surgical specimen. HCC treated with TACE. Twenty-one patients with a total of 36 HCC lesions underwent plain and Gadolinium-enhanced MR Imaging before and after TACE. 10 HCC lesions were later surgically resected; 26/36 lesions underwent MR, CT and angiographic follow-up. At short-term follow-up exams (15-30 days), hypointensity was present on enhanced SE T1 weighted sequences in those lesions (5/10) in which complete tumor necrosis was histologically confirmed. In the remaining 5/10 HCC lesions, persistent viable tumor portions were found at pathology. These areas corresponded to areas on hyperintensity of Gadolinium-enhanced SE T1-weighted images. Hypointensity on both SE T2-weighted and enhanced SE T1-weighted images was a characteristic pattern on long-term follow-up MR images in 21/26 unresected lesions; this finding was correlated with devascularization at angiography; the presence of hyperintense areas on SE T2 weighted and enhanced SE T1-weighted images corresponded to the persistence of hypervascular (viable) areas at angiography.

Intra-arterial CT of the liver is a valuable method to evaluate hepatocellular carcinoma (HCC). It consists of an infusion of contrast medium into the hepatic artery during CT scanning. Twelve patients with suspected resectable HCCs were evaluated with CT arteriography before surgery. The results of CT arteriography were compared with those of US, of CT with intravenous contrast medium and of angiography; on the rule, all exams had been performed some days earlier. The diagnosis of HCC was confirmed by US-guided fine-needle biopsy. CT arteriography demonstrated liver lesions in 11 patients. The lesions were hyperdense in 3/11 patients (27.3%) and hypodense and surrounded by a hyperdense ring in 8/11 patients (72.7%). In 4 of 11 patients (36.4%) CT arteriography identified additional tumor nodules and thus surgery was excluded. In the latter cases, on the basis of CT arteriographic findings, US, CT with i.v. contrast medium and angiography were repeated but failed to demonstrate the additional nodules, either because they were too small or because of cirrhotic changes in liver parenchyma. Therefore, CT arteriography is recommended in the evaluation of selected patients, especially when detailed information on liver parenchyma is needed--e.g., before surgery. In these patients CT arteriography can be performed together with preoperative angiography.

The correct staging of renal neoplasms is critical for both prognosis and subsequent treatment planning. This study was aimed at evaluating the accuracy of contrast-enhanced CT, of plain MR and of contrast-enhanced MR in the staging of renal cell carcinomas (RCC). Forty-four consecutive patients with renal masses were evaluated. All of them underwent plain and enhanced CT and 0.5 T plain and Gadolinium-enhanced MR. T1, T2 and Gd-DTPA T1-weighted MR sequences were acquired (500/20; 2000/100). The diagnostic studies were prospectively and separately interpreted by three radiologists. Imaging findings were then correlated with pathologic findings in all cases. The Robson Staging System was used for pathologic classification. The anatomical staging was correctly performed by CT and MR in 36/44 patients (82%) and by Gd-MR in 39/44 (89%). Seven stage-I and 1 stage-IIIC patients were overstaged by enhanced CT and by plain MR (3 patients to stage II and 5 to stage IV A); 5 stage-I patients were over-staged by Gd-MR (4 patients to stage II and 1 to stage IV A). In four cases, in which CT and MR misdiagnosed stage IV A, Gd-MR correctly identified the lack of adjacent organ infiltration. Perinephric spread, venous invasion, metastatic lymphadenopathy and distant metastases were correctly evaluated by the three imaging modalities. Our results suggest that Gd-DTPA could be useful in identifying direct tumor spread to adjacent organs, because of the different enhancement between the cancer and the other tissues.