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In the last decades, an increasing interest has developed towards non-invasive breast lesion treatments, which offer advantages such as the lack of surgery-related complications, better cosmetic outcomes, and less psychological distress. In addition, these treatments could be an option for patients with poor health who are not candidates for surgery. Non-surgical ablation can be performed under magnetic resonance (MR) or ultrasound (US) guidance. US is cheaper and easily available, while contrast-enhanced MR is more accurate, ensuring better safety and efficacy for the patient. Overall results of studies about MRI-guided tumor ablation reported complete ablation rates ranging between 20% and 100%. High-intensity focused ultrasound (HIFU or FUS) is the most studied ablative technique and it is already established as a valid technique for ablation of benign and malignant tumors in various organs. Ultrasound-guided FUS is very useful for young patients who refuse surgery or with multiple nodules; however, MR-guided FUS is more sensitive and allows a better evaluation of thermal accumulation within the ablated tissue or the adjacent structures. Most MR-guided FUS studies used a dedicated high-field MR scanner and complete tumor ablation was reported in 17-90% of cases. Other techniques using thermal tissue destruction are radiofrequency ablation (RFA) and laser interstitial thermal therapy (LITT). Only a few studies assessed the efficacy of these treatments, all were performed with open MR devices. RFA showed complete tumor ablation in 30-96% of patients, while LITT in 10-71%, but all the studies had a small number of patients. Cryoablation obtains tissue ablation by a rapid decrease of temperature, with a complete tumor removal reported in 18-52% of cases with MR guidance. No serious complications were reported with these techniques. Currently, breast conservative surgery replaced radical surgery when possible. Therefore, future research should focus on these treatments to shift towards an even less invasive approach to breast neoplasms. Level of Evidence: 5 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2018;48:1479-1488.

Women who were previously treated for breast cancer (BC) are an important particular subgroup of women at intermediate BC risk. Their breast follow-up should be planned taking in consideration a 1.0-1.5 % annual rate of loco-regional recurrences and new ipsilateral or contralateral BCs during 15-20 years, and be based on a regional/district invitation system. This activity should be carried out by a Department of Radiology integrating screening and diagnostics in the context of a Breast Unit. We recommend the adoption of protocols dedicated to women previously treated for BC, with a clear definition of responsibilities, methods for invitation, site(s) of visits, methods for clinical and radiological evaluation, follow-up duration, role and function of family doctors and specialists. These women will be invited to get a mammogram in dedicated sessions starting from the year after the end of treatment. The planned follow-up duration will be at least 10 years and will be defined on the basis of patient's age and preferences, taking into consideration organizational matters. Special agreements can be defined in the case of women who have their follow-up planned at other qualified centers. Dedicated screening sessions should include: evaluation of familial/personal history (if previously not done) for identifying high-risk conditions which could indicate a different screening strategy; immediate evaluation of mammograms by one or, when possible, two breast radiologists with possible addition of supplemental mammographic views, digital breast tomosynthesis, clinical breast examination, breast ultrasound; and prompt planning of possible further workup. Results of these screening sessions should be set apart from those of general female population screening and presented in dedicated reports. The following research issues are suggested: further risk stratification and effectiveness of follow-up protocols differentiated also for BC pathologic subtype and molecular classification, and evaluation of different models of survivorship care, also in terms of cost-effectiveness.

Background The goals of neoadjuvant chemotherapy (NAC) are to reduce tumor volume and to offer a prognostic indicator in assessing treatment response. Contrast-enhanced magnetic resonance imaging (CE-MRI) is an established method for evaluating response to NAC in patients with breast cancer. Purpose To validate the role of unenhanced MRI (ue-MRI) compared to CE-MRI for assessing response to NAC in women with breast cancer. Material and Methods Seventy-one patients with ongoing NAC for breast cancer underwent MRI before, during, and at the end of NAC. Ue-MRI was performed with T2-weighted sequences with iterative decomposition of water and fat and diffusion-weighted sequences. CE-MRI was performed using three-dimensional T1-weighted sequences before and after administration of gadobenate dimeglumine. Two blinded observers rated ue-MRI and CE-MRI for the evaluation of tumor response. Statistical analysis was performed to compare lesion size and ADC values changes during therapy, as well as inter-observer agreement. Results There were no statistically significant differences between ue-MRI and CE-MRI sequences for evaluation of lesion size at baseline and after every cycle of treatment ( P > 0.05). The mean tumor ADC values at baseline and across the cycles of NAC were significantly different for the responder group. Conclusion Ue-MRI can achieve similar results to CE-MRI for the assessment of tumor response to NAC. ADC values can differentiate responders from non-responders.

This position paper, issued by ICBR/SIRM and GISMa, summarizes the evidence on DBT and provides recommendations for its use. In the screening setting, DBT in adjunct to digital mammography (DM) increased detection rate by 0.5-2.7‰ and decreased false positives by 0.8-3.6% compared to DM alone in observational and double-testing experimental studies. The reduction in recall rate could be less prominent in those screening programs which already have low recall rates with DM. The increase in radiation exposure associated with DM/DBT protocols has been solved by the introduction of synthetic mammograms (sDM) reconstructed from DBT datasets. Thus, whenever possible, sDM/DBT should be preferred to DM/DBT. However, before introducing DBT as a routine screening tool for average-risk women, we should wait for the results of randomized controlled trials and for a statistically significant and clinically relevant reduction in the interval cancer rate, hopefully associated with a reduction in the advanced cancer rate. Otherwise, a potential for overdiagnosis and overtreatment cannot be excluded. Studies exploring this issue are ongoing. Screening of women at intermediate risk should follow the same recommendations, with particular protocols for women with previous BC history. In high-risk women, if mammography is performed as an adjunct to MRI or in the case of MRI contraindications, sDM/DBT protocols are suggested. Evidence exists in favor of DBT usage in women with clinical symptoms/signs and asymptomatic women with screen-detected findings recalled for work-up. The possibility to perform needle biopsy or localization under DBT guidance should be offered when DBT-only findings need characterization or surgery.

This study was designed to evaluate preliminarily the feasibility and safety of magnetic resonance-guided focused ultrasound (MRgFUS) for treatment of solid tumors in the upper abdomen. We enrolled one patient with hepatocellular carcinoma and two patients with pancreatic adenocarcinoma for MRgFUS ablation. Treatments were performed on a 3T scanner under controlled respiration. Treatment response was evaluated at 1, 3, and 6 months by assessing the nonperfused volume (NPV) of ablated tissue at MR and the degree of pain severity and pain interference. In the patient with HCC, NPV was 100 % after treatment and 85 % at 3 and 6 months follow-up. Histological analysis after liver transplantation showed fibrosis in the ablated area with minimal local tumor recurrence. In the two patients with pancreatic adenocarcinoma, NPV was 80 and 85 % after treatment and 70 and 80 % at 3 and 6 months follow-up. Pain severity and pain interference respectively decreased from a mean of 7 and 6.7 points, respectively, to a mean of 3 and 2 points after treatment. MRgFUS can be feasible and safe in selected patients with solid tumors in abdominal moving organs. However, this technique has several limitations due to the interposition of the rib cage or intestinal loops into the path of the ultrasonic beam, as well as to organ motion. Future technical developments are needed to implement advanced motion detection within the system to control organ and lesion position in real-time and keep the focus of the ultrasound beam on the targeted lesion.

BACKGROUND AND PURPOSE Multiple sclerosis (MS) has been associated with chronic cerebrospinal venous insufficiency. We aim to evaluate the correlation between extracranial veins stenosis evaluated with MR venography (MRV) and clinical/MR parameters of MS. METHODS In 29 consecutive MS patients we performed a standard brain MRI protocol, completed by the evaluation of extra-cerebral venous system using a phase-contrast and a Volumetric Interpolated Breath Hold Examination (VIBE) sequence before and after gadolinium. The T2-proton density images were used to calculate the lesion volume. The jugular veins were evaluated qualitatively (in terms of presence and severity of stenoses) and quantitatively (degree of stenosis). The phase-contrast images were analyzed to calculate the average and peak velocity in the internal jugular veins. RESULTS Postcontrast VIBE successfully showed the jugular veins in all the subjects. T2-lesion-volume was 8.2 [4.6] cm3. A stenosis of the internal jugular veins > of 50% was observed in 10/29(33%) patients. No significant correlation was observed between T2-lesion-volume and degree-of-stenosis (r = .362, P = .302). No different flow parameters were found in the subgroups of patients with and without stenosis (P = .54). CONCLUSIONS In MS the presence/severity of jugular vein stenosis identified with 3T-MRV is not related to MR-visible tissue damage. Moreover no abnormal flow parameters were found in stenosed veins.

Purpose: To determine the preliminary feasibility, safety, and clinical efficacy of magnetic resonance (MR)-guided focused ultrasound for the treatment of painful osteoid osteoma. Materials and Methods: This prospective institutional review board-approved study involved six consecutive patients (five males and one female; mean age, 21 years) with a diagnosis of osteoid osteoma based on clinical and imaging findings. All patients underwent MR-guided focused ultrasound ablation after providing informed consent. Lesions located in the vertebral body were excluded. The number of sonications and the energy deposition were recorded. Treatment success was determined at 1, 3, and±months after treatment. A visual analog scale (VAS) score for pain was used to assess changes in symptoms. MR imaging features of osteoid osteoma (edema, hyperemia, and nidus vascularization) were considered at baseline and at imaging follow-up. Results: Treatment was performed with a mean of 4 sonications±1.8 (standard deviation), with a mean energy deposition of 866 J±211. No treatment-or anesthesia-related complications occurred. The pre-and posttreatment mean VAS scores significantly differed (7.9±1.4 and 0.0±0.0, respectively). At imaging, the edema and hyperemia associated with osteoid osteoma gradually disappeared in all lesions. However, nidus vascularization still persisted after treatment in four of six patients. Conclusion: This limited series demonstrated that MR-guided focused ultrasound treatment of osteoid osteoma can be performed safely with a high rate of success and without apparent treatment-related morbidity. © RSNA, 2013.

The concept of ideal tumor surgery is to remove the neoplastic tissue without damaging adjacent normal structures. High-intensity focused ultrasound (HIFU) was developed in the 1940s as a viable thermal tissue ablation approach. In clinical practice, HIFU has been applied to treat a variety of solid benign and malig- nant lesions, including pancreas, liver, prostate, and breast carcinomas, soft tissue sarcomas, and uterine fibroids. More recently, magnetic resonance guidance has been applied for treatment monitoring during focused ultrasound procedures (magnetic resonance-guided focused ultra- sound, MRgFUS). Intraoperative magnetic resonance imaging provides the best possible tumor extension and dynamic control of energy deposition using real-time magnetic resonance imaging thermometry. We introduce the fundamental principles and clinical indications of the MRgFUS technique; we also report different treatment options and personal outcomes.

Women who underwent chest radiation therapy (CRT) during pediatric/young-adult age (typically, lymphoma survivors) have an increased breast cancer risk, in particular for high doses. The cumulative incidence from 40 to 45 years of age is 13–20 %, similar to that of BRCA mutation carriers for whom contrast-enhanced magnetic resonance imaging (MRI) is recommended. However, in women who underwent CRT, MRI sensitivity is lower (63–80 %) and that of mammography higher (67–70 %) than those observed in women with hereditary predisposition, due to a higher incidence of ductal carcinoma in situ with microcalcifications and low neoangiogenesis. A sensitivity close to 95 % can be obtained only using mammography as an adjunct to MRI. Considering the available evidence, women who underwent CRT before 30 receiving a cumulative dose ≥10 Gy should be invited after 25 (or, at least, 8 years after CRT) to attend the following program: 1. interview about individual risk profile and potential of breast imaging; 2. annual MRI using the same protocol recommended for women with hereditary predisposition; 3. annual bilateral two-view full-field digital mammography or digital breast tomosynthesis (DBT) with synthetic 2D reconstructions. Mammography and MRI can be performed at once or alternately every 6 months. In the case of MRI or contrast material contraindications, ultrasound will be performed instead of MRI. Reporting using BI-RADS is recommended. At the age for entering population screening, the individual risk profile will be discussed with the woman about opting for only mammography/DBT screening or for continuing the intensive protocol.

OBJECTIVE: The objectives of the study were to determine whether perfusion computed tomography (CT-p) and magnetic resonance diffusion-weighted imaging (MR-DWI) can allow evaluation of the effects of chemotherapy combined with antiangiogenetic treatment on liver metastases in patients with advanced colorectal cancer and to determine if changes in CT-p and MR-DWI correlate with the response to therapy as assessed by conventional Response Evaluation Criteria in Solid Tumors (RECIST). METHODS: Eighteen patients with liver metastases from colorectal cancer underwent CT-p and MR-DWI before and 6 months after chemotherapy and antiangiogenetic treatment. Lesions were classified according to RECIST criteria (complete response [CR], partial response [PR], stable disease [SD], and progressive disease) and calculations of CT-p parameters including blood flow (BF), blood volume (BV), capillary permeability (CP), and MR-DWI apparent diffusion coefficient (ADC) values were performed; RECIST, CT-p, and MR-DWI measurements at baseline and follow-up were tested for statistically significant differences using the paired-samples t test. Baseline and follow-up perfusion parameters of the lesions were also compared on the basis of therapy response assessed by RECIST criteria using independent-samples t test. P < 0.05 was considered indicative of a statistically significant difference for all statistical test. RESULTS: Six patients (6/18; 33.3%) were classified as PR (), and the remaining 12 (12/18; 66.7%) were classified as SD. On a per-lesion basis, 2 (2/32; 6.3%) cannot be identified at follow-up, 6 (6/32; 18.8%) showed a decrease in size of more than 30%, and 24 (24/32; 75%) were substantially stable in size. No cases of progressive disease were demonstrated at follow-up. No statistically significant differences were demonstrated between PR, CR, and SD lesions for BF (P = 0.19), BV (P = 0.14), and ADC (P = 0.68) measurements, whereas CP was significantly higher in CR and PR lesions (P = 0.038). Considering differences between baseline and follow-up values, no statistically significant differences were noted between PR and CR lesions versus SD lesions for CT-p values (BF: P = 0.77; BV: P = 0.15; CP: P = 0.64). A statistically significant difference between PR and CR lesions and SD lesions was noted for ADC values (P = 0.047). CONCLUSION: Both CT-p and MR-DWI can detect therapy-induced modifications in lesion vascularization before significant changes in size are evident. Copyright © 2011 by Lippincott Williams & Wilkins.

Atherosclerosis involving the carotid arteries has a high prevalence in the population worldwide. This condition is significant because accidents of the carotid artery plaque are associated with the development of cerebrovascular events. For this reason, carotid atherosclerotic disease needs to be diagnosed and those determinants that are associated to an increased risk of stroke need to be identified. The degree of stenosis typically has been considered the parameter of choice to determine the therapeutical approach, but several recently published investigations have demonstrated that the degree of luminal stenosis is only an indirect indicator of the atherosclerotic process and that direct assessment of the plaque structure and composition may be key to predict the development of future cerebrovascular ischemic events. The concept of "vulnerable plaque" was born, referring to those plaque's parameters that concur to the instability of the plaque making it more prone to the rupture and distal embolization. The purpose of this review is to describe the imaging characteristics of "vulnerable carotid plaques."

Magnetic resonance (MR) imaging-guided focused ultrasound is an alternative noninvasive method for reducing the pain in skeletal metastases. MR imaging-guided focused ultrasound ablation offers several key advantages over other noninvasive treatment modalities. This technology enables the performance of three-dimensional treatment planning with MR imaging and continuous temperature mapping of treated tissue by using MR thermometry, thereby enabling real-time monitoring of thermal damage in the target zone. The concentration of acoustic energy on the intact surface of cortical bone produces a rapid temperature increase that mediates critical thermal damage to the adjacent periosteum, the most innervated component of mature bone tissue. Such thermal ablation has been shown to be an extremely effective approach for pain management. Energy delivered during MR imaging-guided focused ultrasound ablation and accumulated inside the pathologic soft tissue of the metastases can create a variable amount of tissue necrosis. This technique has also a potential role in achieving local tumor control, allowing remineralization of trabecular bone or reduction in lesion size. The current report presents a detailed step-by-step guide for performing MR imaging-guided focused ultrasound ablation of bone metastases, including use of MR thermometry for monitoring treatment, protocol selection for simple palliation of pain or for local tumor control, and a description of imaging features of periosteal neurolysis or metastasis ablation. Two case studies are also presented: in the first, the technique provided palliation of pain in bone metastases, and in the second, the technique achieved tumor control as further proof of primary efficacy. MR imaging-guided focused ultrasound ablation is a promising method for successful palliation of bone metastasis pain and tumor control, because of the bony structure remodeling induced by thermo-related coagulative necrosis.

Objectives: The objectives of this study were to evaluate the efficacy in painmanagement of magnetic resonance (MR)Yguided focused ultrasound for theprimary treatment of painful bone metastases and to assess its potential for localcontrol of bone metastases.Materials and Methods: This was a prospective, single-arm research studywith approval from the institutional review board. Eighteen consecutive patients(female, 8; male, 10; mean [SD] age, 62.7 [11.5] years) with painful bone me-tastases were enrolled. The patients were examined clinically for pain severityand pain interference in accordance with the Brief Pain Inventory-Quality ofLife criteria before and at each follow-up visit. Computed tomography andMR imaging were performed before and at 1 and 3 months after the mag-netic resonanceYguided focused ultrasound treatment. The nonperfused volume(NPV) was calculated to correlate the extension of the ablated pathological tis-sue in the responder and nonresponder patients.Results: No treatment-related adverse events were recorded during the study.The evaluation of pain palliation revealed a statistically significant differencebetween baseline and follow-up values for pain severity and pain interference(P = 0.001, both evaluations). In the evaluation of local tumor control, we ob-served increased bone density with restoration of cortical borders in 5 of the18 patients (27.7%). In accordance with the MD Anderson criteria, completeand partial responses were obtained in 2 of the 18 patients (11.1%) and 4 of the18 patients (22.2%), respectively. Nonperfused volume values ranged between20% and 93%. Mean NPV values remained substantially stable after the treat-ment (P = 0.08). There was no difference in the NPV values between the re-sponder and nonresponder patients (46.7% [24.2%] [25%Y90%] versus 45%[24.9%] [20%Y93%]; P = 0.7).Conclusions: Magnetic resonanceYguided focused ultrasound can be safelyand effectively used as the primary treatment of pain palliation in patientswith bone metastases and has a potential role in local tumor control.Key Words: MRgFUS, high-intensity focused ultrasound, bone metastases,pain palliation, MR-guided interventional radiology, cancer, oncology(Invest Radiol 2013;48: 00Y00)

Purpose: To assess the feasibility of combined first-pass (FP) and steady-state (SS) contrast-enhanced magnetic resonance angiography (MRA) of the peripheral arteries with gadobenate dimeglumine (MultiHance) and to evaluate diagnostic performance relative to digital subtraction angiography (DSA). Materials and methods: A total of 35 patients with symptomatic peripheral arterial occlusive disease (PAOD) underwent FP MRA (repetition time [TR]/echo time [TE]/flip angle [FA]/acquisition time [TA] = 3.5/1.2/30°/14s) at 1.5T after intravenous injection of 10 mL of gadobenate dimeglumine. Thereafter, SS imaging of the calf (TR/TE/FA/TA = 7.5/2.3/20°/40-130s) and femoropopliteal (TR/TE/FA/TA = 7.5/2.3/18°/130-240s) regions was performed after a second injection of 5 mL of gadobenate dimeglumine. All patients underwent conventional DSA. Three readers reviewed separate FP and FP+SS MRA datasets for image quality and presence/absence of clinically relevant PAOD. A fourth independent observer evaluated DSA images. The diagnostic performance (sensitivity, specificity, positive and negative predictive values) achieved with each dataset was determined and compared. Inter-reader agreement was assessed using kappa statistics. Results: The image quality of 134 of 140 vascular regions was optimal or adequate on SS MRA. Inter-reader agreement was good to very good for assessments of FP (κ = 0.725) and combined FP+SS images (κ = 0.866). SS images improved diagnostic confidence in 34 (48.6%) femoropoliteal and 46 (65.7%) crural regions and altered final diagnosis in 8 (11.4%) and 10 (14.3%) regions, respectively. Global diagnostic accuracy increased from 92.9% on FP images to 95.9% on FP+SS images, with significant (P = 0.0384) improvement in the crural region. Conclusion: SS MRA of the peripheral arteries is feasible with gadobenate dimeglumine and potentially improves diagnostic performance in patients with symptomatic PAOD. © 2011 by Lippincott Williams & Wilkins.

Purpose: To evaluate the diagnostic performance and effect on therapeutic management of 64-section computed tomographic (CT) angiography in the assessment of steno-occlusive disease in patients with peripheral arterial disease (PAD), with conventional digital subtraction angiography (DSA) as the reference standard. Materials and Methods: The study protocol was approved by the institutional review board, and written informed consent was obtained from all patients. A total of 212 patients with symptomatic PAD underwent CT angiography and subsequent DSA. For stenosis analysis ( ≥70% stenosis), the arterial bed was divided into 35 segments and evaluated by three readers. Interobserver agreement was determined with generalized k statistics. Accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were calculated. In addition, according to the TransAtlantic Inter-Society Consensus (TASC) Document on Management of Peripheral Arterial Disease guidelines, treatment recommendations based on CT angiographic and DSA fi ndings were compared. McNemar test was used to prove signifi cant differences between CT angiographic and DSA fi ndings. Results: A total of 7420 arterial segments were evaluated, with excellent agreement between readers ( κ ≥ 0.928). On a segmental basis, both sensitivity and specifi city for stenosis of 70% or more were at least 96% (3072 of 3113 segments and 4141 of 4279 segments, respectively), with an accuracy of 98% (7213 of 7392 segments), a PPV of 96% (3072 of 3187 segments), an NPV of 99% (3141 of 3187 segments), a PLR of 36.7, and an NLR of 0.013. There was no significant difference between CT angiographic and DSA findings ( P = .62-.87 ). In accordance with TASC II guidelines, 49 patients were referred for conservative treatment, 87 underwent endovascular procedures, 38 underwent surgery, and 17 received hybrid treatment. Therapy recommendations based on CT angiographic fi ndings alone were identical to those based on DSA fi ndings in all but one patient. Conclusion: The diagnostic performance of 64-section CT angiography is excellent in patients with clinical symptoms of PAD. The results can be used to effectively guide therapeutic decision making in these patients. © RSNA, 2011.

PURPOSE:: To prospectively evaluate the potential of gadobenate dimeglumine for high-resolution steady-state (SS) contrast-enhanced magnetic resonance angiography (CE-MRA) of the carotid arteries as an adjunct to conventional first-pass (FP) MRA, with computed tomography angiography (CTA) and digital subtraction angiography (DSA) as reference. MATERIALS AND METHODS:: Institutional ethics committee approval and written informed consent were obtained. Forty consecutive patients underwent conventional FP MRA with 15 mL gadobenate dimeglumine, using a conventional 3D FLASH sequence (14 sec acquisition time). Immediately afterward, SS images were obtained using a high resolution coronal 3D FLASH sequence (240 sec acquisition time). All patients also underwent CTA and conventional DSA within 8 ± 3 days. Three experienced radiologists assessed FP and SS image quality and calculated sensitivity, specificity, accuracy, and predictive values for stenosis grade and length, plaque morphology, and tandem lesions using DSA as reference. Detected stenoses were quantified and compared (Spearman rank correlation coefficient, [R(s)]; McNemar test) with DSA and CTA findings. Inter-read variability was assessed using kappa (κ) statistics. The impact of SS acquisitions on diagnostic confidence and patient management was assessed. RESULTS:: MRA FP and SS image quality was excellent in 63 (78.8%) and 46 (57.5%) vessels, adequate in 11 (13.8%) and 20 (25.0%) vessels, and poor in 6 (7.5%) and 14 (17.5%) vessels, respectively. Area under the curve analysis revealed no significant differences between MRA FP, MRA FP + SS, and CTA for the grading of stenoses (P = 0.838; accuracy values of 97.4%, 97.4%, and 98.7%, respectively). Greater accuracy (P < 0.001) was noted for FP + SS images over FP images alone for the assessment of plaque morphology (96.1% for FP + SS images vs. 83.3% for FP). Increased diagnostic confidence was noted for 49 (61.3%) vessels because of additional SS images whereas an impact on final diagnosis was noted in 8 (10%) cases. Good correlation was noted between SS image quality and impact on final diagnosis (R(s) = 0.7; P < 0.0001). CONCLUSION:: SS imaging of the carotid arteries is feasible with gadobenate dimeglumine. The increased spatial resolution attainable allows improved evaluation of stenoses and plaque irregularity, yielding comparable diagnostic performance to that of CTA and DSA. © 2009 by Lippincott Williams & Wilkins.

Purpose: To evaluate the diagnostic accuracy of gadofosveset-enhanced magnetic resonance (MR) angiography in the assessment of carotid artery stenosis, with digital subtraction angiography (DSA) as the reference standard, and to determine the value of reading first-pass, steady-state, and "combined" (first-pass plus steady-state) MR angiograms. Materials and Methods: This study was approved by the local ethics committee, and all subjects gave written informed consent. MR angiography and DSA were performed in 84 patients (56 men, 28 women; age range, 61-76 years) with carotid artery stenosis at Doppler ultrasonography. Three readers reviewed the first-pass, steady-state, and combined MR data sets, and one independent observer evaluated the DSA images to assess stenosis degree, plaque morphology and ulceration, stenosis length, and tandem lesions. Interobserver agreement regarding MR angiographic findings was analyzed by using intraclass correlation and Cohen κ coefficients. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated by using the McNemar test to determine possible significant differences (P < .05). Results: Interobserver agreement regarding all MR angiogram readings was substantial. For grading stenosis, sensitivity, specificity, PPV, and NPV were, respectively, 90%, 92%, 91%, and 91% for first-pass imaging; 95% each for steady-state imaging; and 96%, 99%, 99%, and 97% for combined imaging. For evaluation of plaque morphology, respective values were 84%, 86%, 88%, and 82% for first-pass imaging; 98%, 97%, 98%, and 97% for steady-state imaging; and 98%, 100%, 100%, and 97% for combined imaging. Differences between the first-pass, steady-state, and combined image readings for assessment of stenosis degree and plaque morphology were significant (P < .001). Conclusion: Gadofosveset-enhanced MR angiography is a promising technique for imaging carotid artery stenosis. Steady-state image reading is superior to first-pass image reading, but the combined reading protocol is more accurate. © RSNA, 2009.

A comprehensive whole-body approach to noninvasive evaluation of coronary and extracoronary vasculature is currently not available. The objective of our study was to assess the potential of 64-slice computed tomography angiography (64-CTA) for whole-body evaluation of atherosclerosis burden. Seventy-eight patients referred for coronary imaging underwent whole-body 64-CTA using an adjusted strategy for the administration of contrast medium with dose-saving algorithms involving ECG modulation and reduced tube voltage. Arterial segments (15 coronary, 32 systemic) were evaluated for significant (or =50%) steno-occlusive disease while arterovenous density was evaluated at seven extracoronary locations. Homogeneous attenuation (mean 321 +/- 20 HU) was obtained throughout the systemic vasculature. Atherosclerosis was observed in 238/995 (24%) coronary and 368/2441 (15%) systemic segments. Significant stenoses/occlusions were present in 214 (21%)/24 (2.5%) coronary segments while asymptomatic clinically relevant stenoses were present in 49 systemic segments. Sensitivity, specificity, positive and negative predictive values of coronary 64-CTA among 52 patients who also underwent quantitative coronary angiography were 92%, 95%, 81% and 98%, respectively. ECG modulation decreased radiation exposure to 14.1-15.4 mSv per patient. Comprehensive, noninvasive assessment of atherosclerosis can be performed by whole-body 64-CTA and may have a positive impact on secondary prevention.

Materials and methods After giving their informed consent 5 patients with histologically proven unresectable pancreatic adenocarcinoma and 1 patient with unresectable right lobe HCC (4 males, 2 females; age range 58-72) underwent MRgFUS treatment on a dedicated 3T unit featuring the ExAblate 2100 system (InSightec). The system is composed by a 200-element transducer located within the MR table. The MR guidance allows a detailed depiction and visualization of the lesion; moreover, the use of the proton resonance frequency (PRF) shift method allows a real time monitoring of the temperature inside the target lesion and the adjacent anatomical structures, in order to ensure adequate tissue ablation and safe ablation margins. The treatment was performed in general anesthesia with breath control. After the procedure, gadolinium-enhanced gradient echo T1-weighted sequences were performed in order to evaluate the ablated area and the absence of possible local complications. Clinical and imaging follow-up was performed with both MR and CT at 3 and 6 months after treatment respectively for the patient with HCC and those with pancreatic cancer. Results Treatment was successfully performed in all patients without any adverse events during or after the procedure. MR images acquired immediately after treatment demonstrated necrosis of ablated area within the lesion in all cases; in particular the HCC was completely non-enhancing. At short term clinical follow-up, all the patients with pancreatic cancer referred reduction of pain symptoms due to infiltration of the celiac plexus. However follow-up imaging demonstrated recurrence of pathologic tissue within the ablated area, even if there was no local progression of the disease. Two patients with pancreatic cancer underwent radiotherapy after treatment, while the remaining one underwent another MRgFUS ablation.

Materials and method 110 leiomyomas in 98 women (average age 39,3 years) were treated with MRI-guided focused ultrasound (MRgFUS). The treatment is carried out using the ablative properties of the HIFU system under 3T MRI guide. Symptoms (e.g. menorrhagia, pelvic pain) were scored using Severity Score (SS) and quality of life was determined using the UFS-QOL score. Pre-treatment measurementes of leiomyoma volume were obtained by MR images. Immediately after treatment, Non-perfused Volume (NPV) was calculated from T1-w contrastenhanced MR sequences. The average volume of treated fibroids was 90.27 ± 90.4 mm3. Follow-up images were obtained at 3 and 12 months after treatment and served to determine leiomyoma shrinkage. Qualitative and quantitative relations between fibroid volume, NPV ratio at treatment, and 12-month shrinkage were measured.