Hybrid PET/MRI of large vessel vasculitis : Radiation dose compared to PET/CT with view on cumulative effective dose.

BACKGROUND: The diagnosis of large vessel vasculitis (LVV) is often challenging due to the various clinical appearances and the low prevalence. Hybrid imaging by positron emission tomography and computed tomography (PET/CT) is a highly relevant imaging modality for diagnostics and disease surveillance but may be associated with a significant amount of radiation dose especially in patients with complications. OBJECTIVE: The aim of this retrospective analysis was to compare the image quality and impact of hybrid imaging methods PET/CT and PET/MRI on the potential for dose reduction. METHODS: This retrospective single-center study included a cohort of 32 patients who were referred to PET/MRI for the evaluation of LVV, including graft infections and fever of unknown origin. This cohort was compared to a similar cohort of 37 patients who were examined with PET/CT in the same period. Mean radiation dose as well as image quality to establish a diagnosis were compared between the groups. RESULTS: The mean radiation dose applied in PET/MRI was significantly lower when compared to PET/CT (mean 6.6 mSV vs. 31.7 mSV; p < 0.001). This effect was based on the partially multiphasic CT protocols. At the same time, diagnostic image quality using a 4-point scale showed similar results for both imaging modalities in the work-up of LVV. CONCLUSION: With PET/MRI, the radiation exposure can be significantly reduced with similar image quality and diagnostic impact. Patients with LVV have a higher risk of receiving a clinically relevant cumulative effective dose (CED) and PET/MRI should be made available to them.

Mammography in combination with breast ultrasonography versus mammography for breast cancer screening in women at average risk.

BACKGROUND: Screening mammography can detect breast cancer at an early stage. Supporters of adding ultrasonography to the screening regimen consider it a safe and inexpensive approach to reduce false-negative rates during screening. However, those opposed to it argue that performing supplemental ultrasonography will also increase the rate of false-positive findings and can lead to unnecessary biopsies and treatments. OBJECTIVES: To assess the comparative effectiveness and safety of mammography in combination with breast ultrasonography versus mammography alone for breast cancer screening for women at average risk of breast cancer. SEARCH METHODS: We searched the Cochrane Breast Cancer Group's Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), and ClinicalTrials.gov up until 3 May 2021. SELECTION CRITERIA: For efficacy and harms, we considered randomised controlled trials (RCTs) and controlled non-randomised studies enrolling at least 500 women at average risk for breast cancer between the ages of 40 and 75. We also included studies where 80% of the population met our age and breast cancer risk inclusion criteria. DATA COLLECTION AND ANALYSIS: Two review authors screened abstracts and full texts, assessed risk of bias, and applied the GRADE approach. We calculated the risk ratio (RR) with 95% confidence intervals (CI) based on available event rates. We conducted a random-effects meta-analysis. MAIN RESULTS: We included eight studies: one RCT, two prospective cohort studies, and five retrospective cohort studies, enrolling 209,207 women with a follow-up duration from one to three years. The proportion of women with dense breasts ranged from 48% to 100%. Five studies used digital mammography; one study used breast tomosynthesis; and two studies used automated breast ultrasonography (ABUS) in addition to mammography screening. One study used digital mammography alone or in combination with breast tomosynthesis and ABUS or handheld ultrasonography. Six of the eight studies evaluated the rate of cancer cases detected after one screening round, whilst two studies screened women once, twice, or more. None of the studies assessed whether mammography screening in combination with ultrasonography led to lower mortality from breast cancer or all-cause mortality. High certainty evidence from one trial showed that screening with a combination of mammography and ultrasonography detects more breast cancer than mammography alone. The J-START (Japan Strategic Anti-cancer Randomised Trial), enrolling 72,717 asymptomatic women, had a low risk of bias and found that two additional breast cancers per 1000 women were detected over two years with one additional ultrasonography than with mammography alone (5 versus 3 per 1000; RR 1.54, 95% CI 1.22 to 1.94). Low certainty evidence showed that the percentage of invasive tumours was similar, with no statistically significant difference between the two groups (69.6% (128 of 184) versus 73.5% (86 of 117); RR 0.95, 95% CI 0.82 to 1.09). However, positive lymph node status was detected less frequently in women with invasive cancer who underwent mammography screening in combination with ultrasonography than in women who underwent mammography alone (18% (23 of 128) versus 34% (29 of 86); RR 0.53, 95% CI 0.33 to 0.86; moderate certainty evidence). Further, interval carcinomas occurred less frequently in the group screened by mammography and ultrasonography compared with mammography alone (5 versus 10 in 10,000 women; RR 0.50, 95% CI 0.29 to 0.89; 72,717 participants; high certainty evidence). False-negative results were less common when ultrasonography was used in addition to mammography than with mammography alone: 9% (18 of 202) versus 23% (35 of 152; RR 0.39, 95% CI 0.23 to 0.66; moderate certainty evidence). However, the number of false-positive results and necessary biopsies were higher in the group with additional ultrasonography screening. Amongst 1000 women who do not have cancer, 37 more received a false-positive result when they participated in screening with a combination of mammography and ultrasonography than with mammography alone (RR 1.43, 95% CI 1.37 to 1.50; high certainty evidence). Compared to mammography alone, for every 1000 women participating in screening with a combination of mammography and ultrasonography, 27 more women will have a biopsy (RR 2.49, 95% CI 2.28 to 2.72; high certainty evidence). Results from cohort studies with methodological limitations confirmed these findings. A secondary analysis of the J-START provided results from 19,213 women with dense and non-dense breasts. In women with dense breasts, the combination of mammography and ultrasonography detected three more cancer cases (0 fewer to 7 more) per 1000 women screened than mammography alone (RR 1.65, 95% CI 1.0 to 2.72; 11,390 participants; high certainty evidence). A meta-analysis of three cohort studies with data from 50,327 women with dense breasts supported this finding, showing that mammography and ultrasonography combined led to statistically significantly more diagnosed cancer cases compared to mammography alone (RR 1.78, 95% CI 1.23 to 2.56; 50,327 participants; moderate certainty evidence). For women with non-dense breasts, the secondary analysis of the J-START study demonstrated that more cancer cases were detected when adding ultrasound to mammography screening compared to mammography alone (RR 1.93, 95% CI 1.01 to 3.68; 7823 participants; moderate certainty evidence), whilst two cohort studies with data from 40,636 women found no statistically significant difference between the two screening methods (RR 1.13, 95% CI 0.85 to 1.49; low certainty evidence). AUTHORS' CONCLUSIONS: Based on one study in women at average risk of breast cancer, ultrasonography in addition to mammography leads to more screening-detected breast cancer cases. For women with dense breasts, cohort studies more in line with real-life clinical practice confirmed this finding, whilst cohort studies for women with non-dense breasts showed no statistically significant difference between the two screening interventions. However, the number of false-positive results and biopsy rates were higher in women receiving additional ultrasonography for breast cancer screening. None of the included studies analysed whether the higher number of screen-detected cancers in the intervention group resulted in a lower mortality rate compared to mammography alone. Randomised controlled trials or prospective cohort studies with a longer observation period are needed to assess the effects of the two screening interventions on morbidity and mortality.

Whole-Body [18F]FDG-PET/MRI vs. [18F]FDG-PET/CT in Malignant Melanoma.

PURPOSE: To assess the diagnostic performance of simultaneous whole-body 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography (PET)/magnetic resonance imaging (MRI) compared to [18F]FDG PET/x-ray computed tomography (CT) for detection of distant metastatic disease in patients with malignant melanoma. PROCEDURES: We included patients with malignant melanoma who underwent a single injection [18F]FDG dual-imaging protocol that included whole-body PET/CT and subsequent whole-body PET/MRI for staging or restaging purposes in a prospective setting. Images from both modalities were analyzed by two rater teams for the presence of metastatic lesions. PET/CT-PET/MRI overall agreement as well as region-based accuracies, sensitivities (Se), and specificities (Sp) were computed. RESULTS: Between July 2014 and December 2018, 22 patients were enrolled. Interrater agreement and overall accuracy (consensus reading) were 78.8 % (95 % CI 71-84.9) and 96.1 % (95 % CI 92.3-98) for PET/MRI and 78 % (70.2-84.3) and 97.4 % (95 % CI 93.7-98.9) for PET/CT, respectively (P = 0.42). PET/MRI reached a region-based Se of 89.1 % (95 % CI 79.4-94.5) and a Sp of 100 %, whereas PET/CT showed a region-based Se of 92.7 % (95 % CI 84-96.9) and a Sp of 100 % for the detection of metastatic disease in malignant melanoma. CONCLUSIONS: Whole-body [18F]FDG-PET/MRI appears to be comparable to [18F]FDG-PET/CT for lesion detection in patients with malignant melanoma.

PET/MRI versus PET/CT in oncology: a prospective single-center study of 330 examinations focusing on implications for patient management and cost considerations.

PURPOSE: PET/MRI has recently been introduced into clinical practice. We prospectively investigated the clinical impact of PET/MRI compared with PET/CT, in a mixed population of cancer patients, and performed an economic evaluation of PET/MRI. METHODS: Cancer patients referred for routine staging or follow-up by PET/CT underwent consecutive PET/CT and PET/MRI, using single applications of [18F]FDG, [68Ga]Ga-DOTANOC, or [18F]FDOPA, depending on tumor histology. PET/MRI and PET/CT were rated separately, and lesions were assessed per anatomic region; based on regions, per-examination and per-patient accuracies were determined. A simulated, multidisciplinary team meeting served as reference standard and determined whether differences between PET/CT and PET/MRI affected patient management. The McNemar tests were used to compare accuracies, and incremental cost-effectiveness ratios (ICERs) for PET/MRI were calculated. RESULTS: Two hundred sixty-three patients (330 same-day PET/CT and PET/MRI examinations) were included. PET/MRI was accurate in 319/330 examinations and PET/CT in 277/330 examinations; the respective accuracies of 97.3% and 83.9% differed significantly (P < 0.001). The additional findings on PET/MRI-mainly liver and brain metastases-had implications for patient management in 21/263 patients (8.0%). The per-examination cost was 596.97 EUR for PET/MRI and 405.95 EUR for PET/CT. ICERs for PET/MRI were 14.26 EUR per percent of diagnostic accuracy and 23.88 EUR per percent of correctly managed patients. CONCLUSIONS: PET/MRI enables more appropriate management than PET/CT in a nonnegligible fraction of cancer patients. Since the per-examination cost is about 50% higher for PET/MRI than for PET/CT, a histology-based triage of patients to either PET/MRI or PET/CT may be meaningful.

MRI and PET/MRI in hematologic malignancies.

The role of MRI differs considerably between the three main groups of hematological malignancies: lymphoma, leukemia, and myeloma. In myeloma, whole-body MRI (WB-MRI) is recognized as a highly sensitive test for the assessment of myeloma, and is also endorsed by clinical guidelines, especially for detection and staging. In lymphoma, WB-MRI is presently not recommended, and merely serves as an alternative technique to the current standard imaging test, [18 F]FDG-PET/CT, especially in pediatric patients. Even for lymphomas with variable FDG avidity, such as extranodal mucosa-associated lymphoid tissue lymphoma (MALT), contrast-enhanced computed tomography (CT), but not WB-MRI, is presently recommended, despite the high sensitivity of diffusion-weighted MRI and its ability to capture treatment response that has been reported in the literature. In leukemia, neither MRI nor any other cross-sectional imaging test (including positron emission tomography [PET]) is currently recommended outside of clinical trials. This review article discusses current clinical applications as well as the main research topics for MRI, as well as PET/MRI, in the field of hematological malignancies, with a focus on functional MRI techniques such as diffusion-weighted imaging and dynamic contrast-enhanced MRI, on the one hand, and novel, non-FDG PET imaging probes such as the CXCR4 radiotracer [68 Ga]Ga-Pentixafor and the amino acid radiotracer [11 C]methionine, on the other hand. Level of Evidence: 5 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;51:1325-1335.

RECIL versus Lugano for Treatment Response Assessment in FDG-Avid Non-Hodgkin Lymphomas: A Head-to-Head Comparison in 54 Patients.

The response evaluation criteria in lymphoma (RECIL) classification for lymphoma treatment response assessment was introduced in 2017, but it has not yet been compared to the established Lugano classification. Also, the value of the provisional "minor response" (MiR) category of RECIL is unclear. In 54 patients with FDG-avid non-Hodgkin lymphomas (41 diffuse large B-cell lymphomas (DLBCL) and 13 follicular lymphomas), [18F]FDG-PET/CT-based response according to RECIL and Lugano was determined at interim and end-of-treatment (EOT) restaging. Rates of agreement and Cohen's kappa (κ) coefficients were calculated. The relationship between RECIL and Lugano responses and 2-year complete remission (CR) status of DLBCL patients was determined. At interim restaging, MiR was observed in 14.8%, and at EOT, in 5.6% of patients. When MiR was recoded as partial remission, agreement between RECIL and Lugano was 83.3% at interim restaging (κ = 0.69), and 90.7% at EOT (κ = 0.79). 85.4%, of DLBCL patients with responding disease at interim restaging according to both RECIL and Lugano achieved 2-year CR status; whereas, at EOT, 82.9% of patients with responding disease according to Lugano, and 85.4% of patients with responding disease according to RECIL, achieved 2-year CR status. Thus, RECIL and Lugano classifications show comparable performance for treatment response assessment, and a similar association with 2-year CR status in FDG-avid lymphomas.

Is there a reliable size cut-off for splenic involvement in lymphoma? A [18F]FDG-PET controlled study.

PURPOSE: Aim of present study was to determine whether the currently recommended 13-cm cranio-caudal diameter cut-off on CT for assessment of splenic involvement in lymphoma offers adequate sensitivity and specificity. MATERIALS AND METHODS: Patients with histologically proven lymphoma who had undergone [18F]FDG-PET/CT before therapy were included. Cranio-caudal diameters of the spleen were measured on the CT component of PET/CT, and ROC analyses with calculation of respective areas under the curve (AUC) were used to determine cut-off values of cranio-caudal measurements with their respective sensitivities and specificities, using [18F]FDG-PET as the reference standard. RESULTS: In 93 patients, we found a sensitivity of 74.1% and a specificity of 47% for the 13-cm splenic diameter cut-off. CONCLUSIONS: Our results show reasonable, though far from perfect sensitivities and specificities for the currently recommend 13-cm splenic diameter cut-off.

DWI-MRI vs CT in gastric MALT lymphoma-preliminary results in 19 patients.

OBJECTIVE: To assess the diagnostic performance of [F18] fluoro-2-desoxy-D-glucose positron emission tomography/CT [(18F) FDG-PET/CT] compared to diffusion-weighted imaging (DWI)-MRI of lesion detection in patients with non-FDG avid gastric mucosa-associated lymphoid tissue (MALT) lymphoma. METHODS: 19 patients with histologically proven gastric MALT lymphoma were included in this prospective Institutional Review Board-approved study. Patients underwent [18F]-FDG-PET/CT and consecutive MRI/DWI. Images were evaluated for the presence of gastric lesions in two anatomically defined groups (region 1: cardia, body, fundus; region 2: antrum, pyloric region) by two senior board-certified radiologists, in an observer-blinded manner. Overall accuracy relative to the reference standard (histology obtained by biopsy) was calculated for each reader and a consensus rating. RESULTS: We found a statistically significant higher accuracy of lesion detection for lesions in region 1 (p = 0.030) and 2 (p = 0.070) for DWI-MRI (100%/78.9%) than for CT (68.4%/42.1%). CONCLUSION: DWI-MRI seems to be superior accurate to CT for lesion detection in non-FDG avid gastric MALT lymphoma. Advances in knowledge: DWI-MRI seems to be an alternative reliable imaging method for locoregional disease evaluation of non-FDG avid gastric MALT lymphoma.

CT colonography: size reduction of submerged colorectal polyps due to electronic cleansing and CT-window settings.

OBJECTIVES: To assess whether electronic cleansing (EC) of tagged residue and different computed tomography (CT) windows influence the size of colorectal polyps in CT colonography (CTC). METHODS: A database of 894 colonoscopy-validated CTC datasets of a low-prevalence cohort was retrospectively reviewed to identify patients with polyps ≥6 mm that were entirely submerged in tagged residue. Ten radiologists independently measured the largest diameter of each polyp, two-dimensionally, before and after EC in colon, bone, and soft-tissue-windows, in randomised order. Differences in size and polyp count before and after EC were calculated for size categories ≥6 mm and ≥10 mm. Statistical testing involved 95% confidence interval, intraclass correlation and mixed-model ANOVA. RESULTS: Thirty-seven patients with 48 polyps were included. Mean polyp size before EC was 9.8 mm in colon, 9.9 mm in bone and 8.2 mm in soft-tissue windows. After EC, the mean polyp size decreased significantly to 9.4 mm in colon, 9.1 mm in bone and 7.1 mm in soft-tissue windows. Compared to unsubtracted colon windows, EC, performed in colon, bone and soft-tissue windows, led to a shift of 6 (12,5%), 10 (20.8%) and 25 (52.1%) polyps ≥6 mm into the next smaller size category, thus affecting patient risk stratification. CONCLUSIONS: EC and narrow CT windows significantly reduce the size of polyps submerged in tagged residue. Polyp measurements should be performed in unsubtracted colon windows. KEY POINTS: • EC significantly reduces the size of polyps submerged in tagged residue. • Abdominal CT-window settings significantly underestimate 2D sizes of submerged polyps. • Size reduction in EC is significantly greater in narrow than wide windows. • Underestimation of polyp size due to EC may lead to inadequate treatment. • Polyp measurements should be performed in unsubtracted images using a colon window.

Ultra-early response assessment in lymphoma treatment: [18F]FDG PET/MR captures changes in glucose metabolism and cell density within the first 72 hours of treatment.

PURPOSE: To determine whether, in patients with Hodgkin lymphoma (HL) or non-Hodgkin lymphoma (NHL), [18F]FDG PET/MR can capture treatment effects within the first week after treatment initiation, and whether changes in glucose metabolism and cell density occur simultaneously. METHODS: Patients with histologically proven HL or NHL were included in this prospective IRB-approved study. Patients underwent [18F]FDG PET/MR before, and then 48-72 h after (follow-up 1, FU-1) and 1 week after (FU-2) initiation of the first cycle of their respective standard chemotherapy (for HL) or immunochemotherapy (for NHL). Standardized [18F]FDG uptake values (SUVmax, SUVmean) and apparent diffusion coefficients (ADCmin, ADCmean) based on diffusion-weighted MRI, and metabolic and morphological tumour volumes (MTV, VOL) were assessed at each time-point. Multilevel analyses with an unstructured covariance matrix, and pair-wise post-hoc tests were used to test for significant changes in SUVs, ADCs, MTVs and VOLs between the three time-points. RESULTS: A total of 58 patients (11 with HL and 47 with NHL) with 166 lesions were analysed. Lesion-based mean rates of change in SUVmax, SUVmean, ADCmin, ADCmean, MTV and VOL between baseline and FU-1 were -46.8%, -33.3%, +20.3%, +14%, -46% and -12.8%, respectively, and between baseline and FU-2 were -65.1%, -49%, +50.7%, +32.4%, -61.1% and -24.2%, respectively. These changes were statistically significant (P < 0.01) except for the change in VOL between baseline and FU-1 (P = 0.079). CONCLUSION: In lymphoma patients, [18F]FDG PET/MR can capture treatment-induced changes in glucose metabolism and cell density as early as 48-72 h after treatment initiation.

Does elevated glucose metabolism correlate with higher cell density in Neurofibromatosis type 1 associated peripheral nerve sheath tumors?

PURPOSE: To investigate whether elevated glucose metabolism in neurofibroma, determined by [F18]-FDG-PET, is correlated with cell density in MRI, as expressed through the apparent diffusion coefficient. MATERIALS AND METHODS: Patients diagnosed with neurofibromatosis type 1 and peripheral nerve sheath tumors (PNST) were enrolled in this prospective, IRB-approved study. After a single [F18]-FDG injection, patients consecutively underwent [F18]-FDG-PET/CT and [F18]-FDG-PET/MRI on the same day. Maximum and mean standardized uptake values (SUVmax, SUVmean) on [F18]-FDG-PET/CT and [F18]-FDG-PET/MRI were compared, and correlated with minimum and mean apparent diffusion coefficients (ADCmean, ADCmin). RESULTS: A total of 12 (6 male/6 female, mean age was 16.2 ± 5.2 years) patients were prospectively included and analyzed on a per-lesion (n = 39) basis. The SUVmean of examined PNST showed a moderate negative correlation with the ADCmean (r = -.441) and ADCmin (r = -.477), which proved to be statistically significant (p = .005 and p = .002). The SUVmax of the respective lesions, however, showed a weaker negative correlation for ADCmean (r: -.311) and ADCmin (r: -.300) and did not reach statistical significance (p = .054 and p = .057). Lesion-based correlation between [F18]-FDG-PET/MRI and [F18]-FDG-PET/CT showed a moderate correlation for SUVmax (r = .353; p = .027) and a strong one for SUVmean (r = .879; p = .001)). Patient-based liver uptake (SUVmax and mean) of [F18]-FDG-PET/MRI and [F18]-FDG-PET/CT were strongly positively correlated (r = .827; p < .001 and r = .721; p < .001) but differed significantly (p < .001). CONCLUSIONS: We found a statistically significant, negative correlation between glucose metabolism and cell density in PNST. Thus, ADCmean and ADCmin could possibly add complimentary information to the SUVmax and SUVmean and may serve as a potential determinant of malignant transformation of PNST.

Whole-Body 68Ga-DOTANOC PET/MRI Versus 68Ga-DOTANOC PET/CT in Patients With Neuroendocrine Tumors: A Prospective Study in 28 Patients.

PURPOSE: The aim of this study was to assess the diagnostic performance of simultaneous whole-body Ga-DOTANOC PET/MRI compared with Ga-DOTANOC PET/CT for detection of distant metastatic disease in patients with well-differentiated neuroendocrine tumors (NETs). METHODS: Patients with histologically proven, well-differentiated NET (G1 or G2) were included in this prospective, institutional review board-approved study. Patients underwent Ga-DOTANOC PET/CT and subsequent Ga-DOTANOC PET/MRI after a single tracer injection on the same day for staging or restaging purposes. Images were evaluated for the presence of NET lesions by 2 rater teams, each consisting of a nuclear medicine physician and a radiologist, in an observer-blinded fashion. Overall agreement, accuracy, sensitivity, and specificity, relative to a composite reference standard (consensus review including follow-up data), were calculated. RESULTS: Between July 2014 and June 2016, 28 patients were enrolled. Overall agreement and accuracy between the 2 rater teams were 91.7% (95% confidence interval [CI], 87.5%-95.9%) and 97% (95% CI, 94.4%-99.6%) for PET/MRI and 92.3% (95% CI, 88.3%-96.3%) and 94.6% (95% CI, 91.2%-98.1%) for PET/CT, respectively (P = 1.00).Overall, PET/MRI reached 89.8% sensitivity (95% CI, 77.8%-96.6%) and 100% specificity (95% CI, 97%-100%); PET/CT showed 81.6% sensitivity (95% CI, 68%-91.2%) and 100% specificity (95% CI, 97%-100%) for the detection of metastatic disease in NETs. CONCLUSIONS: Whole-body Ga-DOTANOC PET/MRI appears to be comparable to Ga-DOTANOC PET/CT for lesion detection in patients with well-differentiated NETs.

MR neurography of ulnar nerve entrapment at the cubital tunnel: a diffusion tensor imaging study.

OBJECTIVES: MR neurography, diffusion tensor imaging (DTI) and tractography at 3 Tesla were evaluated for the assessment of patients with ulnar neuropathy at the elbow (UNE). METHODS: Axial T2-weighted and single-shot DTI sequences (16 gradient encoding directions) were acquired, covering the cubital tunnel of 46 patients with clinically and electrodiagnostically confirmed UNE and 20 healthy controls. Cross-sectional area (CSA) was measured at the retrocondylar sulcus and FA and ADC values on each section along the ulnar nerve. Three-dimensional nerve tractography and T2-weighted neurography results were independently assessed by two raters. RESULTS: Patients showed a significant reduction of ulnar nerve FA values at the retrocondylar sulcus (p = 0.002) and the deep flexor fascia (p = 0.005). At tractography, a complete or partial discontinuity of the ulnar nerve was found in 26/40 (65%) of patients. Assessment of T2 neurography was most sensitive in detecting UNE (sensitivity, 91%; specificity, 79%), followed by tractography (88%/69%). CSA and FA measurements were less effective in detecting UNE. CONCLUSION: T2-weighted neurography remains the most sensitive MR technique in the imaging evaluation of clinically manifest UNE. DTI-based neurography at 3 Tesla supports the MR imaging assessment of UNE patients by adding quantitative and 3D imaging data. KEY POINTS: • DTI and tractography support conventional MR neurography in the detection of UNE • Regionally reduced FA values and discontinuous tractography patterns indicate UNE • T2-weighted MR neurography remains the imaging gold standard in cases of UNE • DTI-based ulnar nerve tractography offers additional topographic information in 3D.

The role of imaging specialists as authors of systematic reviews on diagnostic and interventional imaging and its impact on scientific quality: report from the EuroAIM Evidence-based Radiology Working Group.

PURPOSE: To evaluate the inclusion of radiologists or nuclear medicine physicians (imaging specialists) as authors of systematic reviews (SRs) on imaging and imaging-guided diagnostic procedures and to determine the impact of imaging specialists' presence as authors on the overall quality of the reviews. MATERIALS AND METHODS: A MEDLINE and EMBASE search was performed for SRs of diagnostic and interventional image-guided procedures that were published from January 2001 to December 2010. SRs about procedures primarily performed by nonimaging specialists were excluded. The inclusion of imaging specialists among the SR authors and the frequency of publication in imaging journals were evaluated. The quality of a subset of 200 SRs (100 most recent SRs with imaging specialists as authors and 100 most recent SRs without imaging specialists as authors) was rated by using a 12-item modified assessment of multiple SRs (AMSTAR) evaluation tool. Spearman, χ(2), and Mann-Whitney statistics were used. RESULTS: From among 3258 retrieved citations, 867 SRs were included in the study. Neuroimaging had the largest number of SRs (28% [241 of 867]), 41% (354 of 867) of SRs concerned diagnostic performance, and 26% (228 of 867) of SRs were published in imaging journals. Imaging specialists were authors (in any position) in 330 (38%) of 867 SRs; they were first authors of 176 SRs and last authors of 161 SRs. SRs with imaging specialists as authors were more often published in imaging journals than in nonimaging journals (54% [179 of 330] vs 9% [49 of 537]; P < .001). The median number of modified AMSTAR quality indicators was nine in SRs with imaging specialists as authors, while that in SRs without imaging specialists as authors was seven (P = .003). CONCLUSION: Only 38% (330 of 867) of SRs on radiology or nuclear medicine-related imaging published from January 2001 to December 2010 included imaging specialists as authors. However, the inclusion of imaging specialists as authors was associated with a significant increase in the scientific quality (as judged by using a modified AMSTAR scale) of the SR.

Evaluation of diffusion-weighted MRI for pretherapeutic assessment and staging of lymphoma: results of a prospective study in 140 patients.

PURPOSE: To determine the value of diffusion-weighted MRI (DWI-MRI) for pretherapeutic imaging of fluorodeoxyglucose (FDG)-avid lymphoma and lymphoma with variable FDG avidity. EXPERIMENTAL DESIGN: Treatment-naïve patients with lymphoma who were referred for whole-body staging were included in this prospective study. Group A included patients with FDG-avid lymphoma (e.g., Hodgkin, diffuse large B-cell, and follicular lymphoma), whereas Group B included patients with lymphoma of variable FDG avidity [e.g., extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)]. All patients underwent DWI-MRI and 18F-FDG- positron emission tomography/computed tomography (PET/CT). Region-based sensitivity and agreement with Ann Arbor staging, relative to the reference standard, were calculated for DWI-MRI, and, in Group B, also 18F-FDG-PET/CT and contrast-enhanced (CE-) CT. RESULTS: In Group A (100 patients), DWI-MRI had a region-based sensitivity of 97%, and with regard to staging, agreed with the reference standard in 94 of 100 patients (κ, 0.92). In Group B (40 patients; 38 MALT lymphomas and 2 small lymphocytic lymphomas/chronic lymphocytic leukemias), DWI-MRI, 18F-FDG-PET/CT, and CE-CT had region-based sensitivities of 94.4%, 60.9%, and 70.7%, respectively. With regard to staging in Group B, DWI-MRI, 18F-FDG-PET/CT, and CE-CT agreed with the reference standard in 37 of 40, 26 of 40, and 24 of 40 patients, with κ values of 0.89, 0.52, and 0.43, respectively. CONCLUSIONS: In patients with FDG-avid lymphoma, DWI-MRI seems to be only slightly inferior to 18F-FDG-PET/CT with regard to pretherapeutic regional assessment and staging. In patients with lymphoma subtypes that show a variable FDG avidity (e.g., MALT lymphoma), DWI-MRI seems to be superior to both 18F-FDG-PET/CT and CE-CT.

Imaging of a case of benign carotidynia with ultrasound, MRI and PET-CT.

We present a case of carotidynia that we believe supports its classification as a distinct inflammatory disease entity. Doppler sonography and cervical magnetic resonance imaging are appropriate imaging modalities for diagnosing presumed carotidynia.

Adjunct ultrasonography for breast cancer screening in women at average risk: a systematic review.

BACKGROUND: Screening with mammography has the ability to detect breast cancer at an early stage but misses some cancers. Supporters of adjunct ultrasonography to the screening regimen argue that it might be a safe and inexpensive approach to reduce the false-negative rates of screening. Critics are concerned that adjunct ultrasonography will also increase the rate of false-positive findings and can lead to unnecessary biopsies and treatments in women at average risk. AIMS: The purpose of this review was to systematically assess the comparative benefits and harms of mammography with adjunct breast ultrasonography and mammography only in breast cancer screening. METHODS: We searched multiple electronic databases and the Cochrane Breast Cancer Group's Specialised Register (from 1995 to February 2012). To detect ongoing or unpublished studies, we searched trial registries and multiple sources of grey literature. Two researchers independently reviewed all abstracts and full-text articles against pre-defined eligibility criteria. We dually rated the risk of bias of studies and the strength of evidence based on established guidance. RESULTS: We did not detect any controlled studies that provide evidence for (or against) the use of adjunct ultrasonography for screening in women at average risk for breast cancer. Extrapolations of results from women at elevated risk for breast cancer indicate that the false-positive rates in women at average risk who were recalled because of positive ultrasonographies will exceed 98%. In women with dense or very dense breast tissue, the evidence regarding the use of adjunct ultrasonography is not conclusive. CONCLUSIONS: No methodologically sound evidence is available justifying the routine use of ultrasonography as an adjunct screening tool in women at average risk for breast cancer. IMPLICATIONS FOR PRACTICE: Clinicians should not use ultrasonography as a screening tool for breast cancer screening on a routine basis. The use should be limited to women with dense breasts for whom the accuracy of mammography is low, or for diagnostic purposes.

Common anatomical variation in patients with idiopathic meralgia paresthetica: a high resolution ultrasound case-control study.

BACKGROUND: Meralgia paresthetica (MP) is a mononeuropathy of the lateral femoral cutaneous nerve (LFCN) characterized by pain, numbness or paresthesia on the anterolateral aspect of the thigh. Though several contributing factors have been identified, the cause of its idiopathic form still remains unclear. Anatomic and clinical studies have demonstrated a variable course for the LFCN and have suggested a contribution to the pathogenesis of MP. OBJECTIVE: It was the aim of the present case-control study to assess the anatomical course and compression site of the LFCN using high resolution ultrasound (HRUS) in patients suffering from idiopathic MP, and compare the anatomical course in these patients to an asymptomatic control group. STUDY DESIGN: Case-control study. SETTING: Nerve imaging center at a large university hospital in Austria. METHODS: Twenty-eight patients with a diagnosis of MP were included in this study (20 men, 8 women; mean age 54 years). The diagnosis was established by clinical history, physical examination, and diagnostic anesthetic block. Fifteen age- and gender-matched healthy volunteers served as the control group. Standardized HRUS examinations were performed by one experienced radiologist from June 2004 through April 2012. Two experienced radiologists reviewed the patients' standardized HRUS examinations and performed examinations in the control group to measure the minimal distance between the LFCN and the anterior superior iliac spine (ASIS). OUTCOMES: The minimal distance between the ASIS and the LFCN was measured using HRUS. RESULTS: The LFCN could be seen in all patients and volunteers. In MP patients, the mean distance between the LFCN and the ASIS was 0.52 cm (SD 0.46 cm), compared to a mean distance of 1.79 cm (SD 1.48 cm) in the control group (P < 0.001). LIMITATIONS: Limited sample size, retrospective design. CONCLUSIONS: The results of this study demonstrate a significantly different course of the LFCN, closer to the ASIS in patients with idiopathic MP.

Mammography in combination with breast ultrasonography versus mammography for breast cancer screening in women at average risk.

BACKGROUND: Breast cancer is the most common malignant disease diagnosed in women worldwide. Screening with mammography has the ability to detect breast cancer at an early stage. The diagnostic accuracy of mammography screening largely depends on the radiographic density of the imaged breasts. In radiographically dense breasts, non-calcified breast cancers are more likely to be missed than in fatty breasts. As a consequence, some cancers are not detected by mammography screening. Supporters of adjunct ultrasonography to the screening regimen for breast cancer argue that it might be a safe and inexpensive approach to reduce the false negative rates of the screening process. Critics, however, are concerned that performing supplemental ultrasonography on women at average risk will also increase the rate of false positive findings and can lead to unnecessary biopsies and treatments. OBJECTIVES: To assess the comparative effectiveness and safety of mammography in combination with breast ultrasonography versus mammography for breast cancer screening for women at average risk of breast cancer. SEARCH METHODS: We searched the Cochrane Breast Cancer Group's Specialised Register, MEDLINE (via OvidSP) and EMBASE up until February 2012.To detect ongoing or unpublished studies, we searched the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov and the National Cancer Institute's clinical trial database until June 2012. In addition, we conducted grey literature searches using the following sources: OpenGrey; National Institute of Health RePORTER; Health Services Research Projects in Progress (HSRPROJ); Hayes, Inc. Health Technology Assessment; The New York Academy of Medicine's Grey Literature Index and Conference Papers Index. SELECTION CRITERIA: For efficacy, we considered randomised controlled trials (RCTs), with either individual or cluster randomisation, and prospective, controlled non-randomised studies with a low risk of bias and a sample size of at least 500 participants.In addition to studies eligible for efficacy, we considered any controlled, non-randomised study with a low risk of bias and a study size of at least 500 participants for the assessment of harms.Our population of interest were women between the ages of 40 and 75 years who were at average risk for breast cancer. DATA COLLECTION AND ANALYSIS: Two review authors screened abstracts and full-text publications against the inclusion criteria. None of the studies met our inclusion criteria. MAIN RESULTS: Our review did not detect any controlled studies on the use of adjunct ultrasonography for screening in women at average risk for breast cancer. One ongoing randomised controlled trial was identified (J-START, Japan). AUTHORS' CONCLUSIONS: Presently, there is no methodologically sound evidence available justifying the routine use of ultrasonography as an adjunct screening tool in women at average risk for breast cancer.

Fotemustine chemoembolization of hepatic metastases from uveal melanoma: a retrospective single-center analysis.

OBJECTIVE: The purpose of the current study was to retrospectively evaluate response and survival in patients with hepatic metastasis from uveal melanoma treated by palliative transarterial chemoembolization (TACE) with fotemustine. MATERIALS AND METHODS: During the study period, 21 patients with hepatic metastases from uveal melanoma were treated by TACE. A series of TACE interventions (mean number per patient, 3.29 interventions; range, 1-6 interventions) was performed on each patient with an emulsion of fotemustine dissolved in 10 mL of saline mixed with 10 mL of an oily contrast agent. Tumor response based on the Response Evaluation Criteria in Solid Tumors was evaluated using contrast-enhanced CT scans obtained 6-10 weeks after embolization. RESULTS: CT showed partial regression after TACE in three patients (14%). Six patients (29%) presented with stable disease but no significant change in tumor size after TACE, and 12 patients (57%) presented with progressive disease after TACE treatment. The overall response rate was 43%. The mean survival after diagnosis of hepatic metastasis was 28.7 months. CONCLUSION: TACE of hepatic metastasis from uveal melanoma with fotemustine is well tolerated, and the survival rates in this study (mean, 28.7 months) are among the longest reported.