Searched for: person:rosena23
Reply to "Retracted Publications Within Journals: Further Causes for Concern" [Letter]
Rosenkrantz, Andrew B
PMID: 27337376
ISSN: 1546-3141
CID: 2159242
Associations Between NIH Funding and Advanced Bibliometric Indices Among Radiological Investigators
Rosenkrantz, Andrew B; Jiang, Anthony
RATIONALE AND OBJECTIVES: Whereas data support the h index (reflecting both publications and citations) as an indicator of academic productivity, other advanced bibliometric indices aiming to address shortcomings of the h index remain poorly studied. Our objective was to compare the associations between bibliometric indices and total National Institutes of Health (NIH) grant funding among investigators within U.S. academic radiology departments. MATERIALS AND METHODS: NIH grant funding amounts for 400 NIH-funded investigators within radiology departments were obtained from Blue Ridge Institute for Medical Research. Investigators' publications and associated citations were identified using Scopus. Indices computed for each investigator included: publication count, citation count, h index, i-10 index, hc index (h index adjusted for recency of publications), m quotient (h index adjusted for career duration), and e index and g index (both account for highly cited articles). Spearman correlations were performed between indices and funding. Multivariable linear regression was performed to identify significant independent predictors of funding. RESULTS: For MD investigators: the indices exhibited no-to-weak correlations with funding (r = 0.173-0.387); m quotient exhibited the largest correlation and was the only significant (albeit weak) independent predictor of funding (P = 0.011). For PhD investigators: correlation with funding was weak for m quotient (r = 0.323), although moderate for other indices (r = 0.518-0.568); publication count exhibited highest correlation; publication count (P < 0.001) and hc index (P = 0.024) were significant independent predictors of funding. CONCLUSIONS: Bibliometric indices were more strongly associated with grant funding for PhD than for MD radiology investigators, with publication count exhibiting the strongest association in the latter group. Time-weighted adjustments, as reflected by the m quotient and hc index, may improve efforts to predict funding using bibliometrics.
PMID: 27040181
ISSN: 1878-4046
CID: 2065942
Performance of Simultaneous High Temporal Resolution Quantitative Perfusion Imaging of Bladder Tumors and Conventional Multi-phase Urography Using a Novel Free-Breathing Continuously Acquired Radial Compressed-Sensing MRI Sequence
Parikh, Nainesh; Ream, Justin M; Zhang, Hoi Cheung; Block, Kai Tobias; Chandarana, Hersh; Rosenkrantz, Andrew B
PURPOSE: To investigate the feasibility of high temporal resolution quantitative perfusion imaging of bladder tumors performed simultaneously with conventional multi-phase MR urography (MRU) using a novel free-breathing continuously acquired radial MRI sequence with compressed-sensing reconstruction. METHODS: 22 patients with bladder lesions underwent MRU using GRASP (Golden-angle RAdial Sparse Parallel) acquisition. Multi-phase contrast-enhanced abdominopelvic GRASP was performed during free-breathing (1.4x1.4x3.0mm3 voxel size; 3:44min acquisition). Two dynamic datasets were retrospectively reconstructed by combining different numbers of sequentially acquired spokes into each dynamic frame: 110 spokes per frame for 25-second temporal resolution (serving as conventional MRU for clinical interpretation) and 8 spokes per frame for 1.7-second resolution. Using 1.7-second resolution images, ROIs were placed within bladder lesions and normal bladder wall, a femoral artery arterial input function was generated, and the Generalized Kinetic Model was applied. RESULTS: Biopsy/cystectomy demonstrated 16 bladder tumors (13 stage>/=T2, 3 stage=T1) and 6 benign lesions. All lesions were well visualized using 25-second clinical multi-phase images. Using 1.7-second resolution images, Ktrans was significantly higher in tumors (0.38+/-0.24) than normal bladder (0.12+/-0.02=8, p<0.001) or benign lesions (0.15+/-0.04, p=0.033). Ratio between Ktrans of lesions and normal bladder was nearly double for tumors than benign lesions (4.3+/-3.4 vs. 2.2+/-1.6), and Ktrans was nearly double in stage>/=T2 than stage=T1 tumors (0.44+/-0.24 vs. 0.24+/-0.24), although these did not approach significance (p=0.180-0.209), possibly related to small sample size. CONCLUSION: GRASP allows simultaneous quantitative high temporal resolution perfusion of bladder lesions during clinical MRU examinations using only one contrast injection and without additional scan time.
PMCID:4896486
PMID: 26740058
ISSN: 1873-5894
CID: 1901182
The Impact Factor of Radiological Journals: Associations with Journal Content and Other Characteristics Over a Recent 12-Year Period
Rosenkrantz, Andrew B; Ayoola, Abimbola
RATIONALE AND OBJECTIVES: The aim of this study was to evaluate the trends in the impact factor (IF) of radiological journals over a recent 12-year period, including associations between IF and journal topic. MATERIALS AND METHODS: Journal Citation Reports (JCR) was used to identify all biomedical journals and all radiological journals (assigned a JCR category of "Radiology, Nuclear Medicine, & Medical Imaging"), along with journal IF, in 2003 and 2014. Radiological journals were manually classified by topic. Trends in median IF (mIF) were assessed. RESULTS: The number of radiological journals increased from 83 (2003) to 125 (2014) (all biomedical journals: 5907 to 8718, respectively). mIF of radiological journals increased from 1.42 (2003) to 1.75 (2014) (all biomedical journals: 0.93 to 1.46, respectively). The most common topic among new radiological journals was general (nonspecialized) radiology (8). Five new radiological journals in 2014 were in topics (cancer imaging and molecular imaging) having no journals in 2003. mIF of general radiological journals was 1.49. Topics having highest mIF were cardiac imaging (2.94), optics (2.86), molecular imaging (2.77), radiation oncology (2.60), and neuroradiology (2.25). Topics with lowest mIF were ultrasound (1.19) and interventional radiology (1.44). Topics with the largest increase in mIF were cardiac imaging (from 1.17 to 2.94) and neuroradiology (from 1.07 to 2.25). CONCLUSIONS: Radiological journals exhibited higher mIF than biomedical journals overall. Among radiological journals, subspecialty journals had highest mIF. While a considerable number of new radiological journals since 2003 were general radiology journals having relatively low IF, there were also new journal topics representing emerging areas of subspecialized radiological research.
PMID: 26992739
ISSN: 1878-4046
CID: 2032232
Prostate Cancer Detection Using Computed Very High b-value Diffusion-weighted Imaging: How High Should We Go?
Rosenkrantz, Andrew B; Parikh, Nainesh; Kierans, Andrea S; Kong, Max Xiangtian; Babb, James S; Taneja, Samir S; Ream, Justin M
RATIONALE AND OBJECTIVES: The aim of this study was to assess prostate cancer detection using a broad range of computed b-values up to 5000 s/mm2. MATERIALS AND METHODS: This retrospective Health Insurance Portability and Accountability Act-compliant study was approved by an institutional review board with consent waiver. Forty-nine patients (63 +/- 8 years) underwent 3T prostate magnetic resonance imaging before prostatectomy. Examinations included diffusion-weighted imaging (DWI) with b-values of 50 and 1000 s/mm2. Seven computed DWI image sets (b-values: 1000, 1500, 2000, 2500, 3000, 4000, and 5000 s/mm2) were generated by mono-exponential fit. Two blinded radiologists (R1 [attending], R2 [fellow]) independently evaluated diffusion weighted image sets for image quality and dominant lesion location. A separate unblinded radiologist placed regions of interest to measure tumor-to-peripheral zone (PZ) contrast. Pathologic findings from prostatectomy served as reference standard. Measures were compared between b-values using the Jonckheere-Terpstra trend test, Spearman correlation coefficient, and generalized estimating equations based on logistic regression for correlated data. RESULTS: As b-value increased, tumor-to-PZ contrast and benign prostate suppression for both readers increased (r = +0.65 to +0.71, P = 0.001), whereas anatomic clarity, visualization of the capsule, and visualization of peripheral-transition zone edge decreased (r = -0.69 to -0.75, P = 0.003). Sensitivity for tumor was highest for R1 at b1500-3000 (84%-88%) and for R2 at b1500-2500 (70%-76%). Sensitivities for both pathologic outcomes were lower for both readers at both b1000 and the highest computed b-values. Sensitivity for Gleason >6 tumor was highest for R1 at b1500-3000 (90%-93%) and for R2 at 1500-2500 (78%-80%). The positive predictive value for tumor for R1 was similar from b1000 to 4000 (93%-98%) and for R2 was similar from b1500 to 4000 (88%-94%). CONCLUSIONS: Computed b-values in the range of 1500-2500 s/mm2 (but not higher) were optimal for prostate cancer detection; b-values of 1000 or 3000-5000 exhibited overall lower performance.
PMID: 26992738
ISSN: 1878-4046
CID: 2032222
Application of anatomically accurate, patient-specific 3D printed models from MRI data in urological oncology
Wake, N; Chandarana, H; Huang, W C; Taneja, S S; Rosenkrantz, A B
PMID: 26983650
ISSN: 1365-229x
CID: 2032012
Prostate Imaging Reporting and Data System (PI-RADS), Version 2: A Critical Look
Rosenkrantz, Andrew B; Oto, Aytekin; Turkbey, Baris; Westphalen, Antonio C
OBJECTIVE: The purpose of this article is to highlight the potential challenges associated with the Prostate Imaging Reporting and Data System, version 2 (PI-RADS v2), and to offer, when possible, suggestions and ideas for improvement. CONCLUSION: PI-RADS v2 offers clear improvements to its earlier version and will greatly benefit the prostate MRI community. Nonetheless, caution remains on the basis of early user experience, and potential ambiguities and gaps of PI-RADS v2 are noted. Continued data-driven clarification and refinement of the guidelines will be invaluable for PI-RADS v2 to achieve its goal of improving patient care.
PMID: 26913638
ISSN: 1546-3141
CID: 1965462
Evaluation for suspected acute appendicitis in the emergency department setting: a comparison of outcomes among three imaging pathways
Rosenkrantz, Andrew B; Labib, Anthony; Ginocchio, Luke A; Babb, James S
PURPOSE: To compare outcomes of imaging pathways in suspected acute appendicitis. METHODS: Computerized tomography (CT) alone, ultrasound alone, and ultrasound followed by CT were compared in 570 emergency department (ED) patients with suspected acute appendicitis. RESULTS: After initial ultrasound, 9.3% of men and 41.0% of women underwent CT. Body mass index (BMI) (P=.036): 25.3+/-5.7kg/m(2) (CT), 19.1+/-3.3kg/m(2) (ultrasound), and 22.4+/-3.2kg/m(2) (ultrasound then CT). Age (P<.001): 35.9+/-14.5 years (CT), 12.8+/-6.2y (ultrasound), and 21.2+/-9.0 years (ultrasound then CT). ED length-of-stay: 7.0+/-2.8h (CT), 5.9+/-2.8h (ultrasound), and 8.4+/-3.5h (ultrasound then CT). Admission, same-day discharge, appendectomy, pathology positive for appendicitis or complicated appendicitis, 30-day repeat ED visit/hospitalization: no difference between pathways (P=.062-1.00). CONCLUSION: Ultrasound, selected in patients with lowest age/BMI, had shortest length-of-stay but otherwise similar outcomes.
PMID: 27317225
ISSN: 1873-4499
CID: 2145372
Radial T1-weighted magnetic resonance imaging: Background, clinical applications, and future directions
Kierans, Andrea S.; Rosenkrantz, Andrew B.
ISI:000375233400006
ISSN: 0160-9963
CID: 2975402
Comparison of MRI features of pathologically proven hepatocellular carcinoma between patients with hepatitis B and hepatitis C infection
Dunst, Diane; Ream, Justin M; Khalef, Victoria; Hajdu, Cristina H; Rosenkrantz, Andrew B
PURPOSE: To compare MRI features of pathologically-proven hepatocellular carcinoma (HCC) between patients with hepatitis B (HBV) and hepatitis C (HCV) infection. METHODS: Two radiologists assessed 51 confirmed HCCs on MRI in HBV (n=18) or HCV (n=33) patients; a third, more experienced, radiologist resolved discrepancies. RESULTS: Arterial hyperenhancement occurred more frequently in HCV (90.9% vs. 66.7%; P=.032), DWI/T2WI hyperintensity more frequently in HBV [(DWI: 78.6% vs. 45.8%, T2WI: 77.8% vs. 48.5%; P=.073-0.088)]. Tumors were larger in HBV (P=.016). Washout, pseudocapsule, homogeneity, circumscribed margins, lipid, iron, and visually low ADC were not different. CONCLUSION: Larger studies are required to confirm these preliminary findings.
PMID: 27133666
ISSN: 1873-4499
CID: 2100762