Faculty Bibliography

OBJECTIVE: The purpose of this study was to compare the reproducibility and diagnostic performance of 2D and 3D ROIs for prostate apparent diffusion coefficient (ADC) measurements. MATERIALS AND METHODS: The study included 56 patients with prostate cancer undergoing 3-T MRI including DWI (b = 50 and 1000 s/mm2) before radical prostatectomy. Histologic findings from prostatectomy specimens were reviewed to denote each patient's dominant tumor and a benign region with visually decreased ADC. Three readers independently measured the ADCs of both areas using an ROI placed on a single slice through the lesion (2D) and an ROI encompassing all slices through the lesion (3D). Readers repeated measurements after 3 weeks. Assessment included Bland-Altman analysis (coefficient of repeatability [CR] in which lower values indicated higher reliability) and ROC analysis. RESULTS: For intrareader variability, the CRs across readers for all ROIs were 9.9% for 2D and 9.3% for 3D. For tumor ROIs the CRs were 10.6% for 2D and 9.6% for 3D. For interreader variability, the CRs across readers for all ROIs were 17.1% for 2D and 20.5% for 3D and for tumor ROIs were 17.9% for 2D and 22.2% for 3D. For combined reader data, the AUCs for benign and malignant findings were 0.77 for 2D and 0.78 for 3D (p = 0.146). For differentiating Gleason score (GS) 3 + 3 from GS > 3 + 3 tumors, the AUCs were 0.92 for 2D and 0.92 for 3D ROIs (p = 0.649). For differentiating GS /= 4 + 3 tumors, the AUCs were 0.70 for 2D and 0.67 for 3D ROIs (p = 0.004). CONCLUSION: Use of a 3D ROI did not improve intrareader or interreader reproducibility or diagnostic performance compared with use of a 2D ROI for prostate ADC measurements. Interreader reproducibility of 2D ROIs was suboptimal nonetheless.

OBJECTIVES: The aim of this study was to compare testicular metabolite concentrations between fertile control subjects and infertile men. MATERIALS AND METHODS: Single voxel proton magnetic resonance spectroscopy ((1)H-MRS) was performed in the testes with and without water suppression at 3 T in 9 fertile control subjects and 9 infertile patients (8 with azoospermia and 1 with oligospermia). In controls only, the T1 and T2 values of water and metabolites were also measured. Absolute metabolite concentrations were calculated using the unsuppressed water signal as a reference and correcting for the relative T1 and T2 weighting of the water and metabolite signals. RESULTS: Testicular T1 values of water, total choline, and total creatine were 2028 +/- 125 milliseconds, 1164 +/- 105 milliseconds, and 1421 +/- 314 milliseconds, respectively (mean +/- standard deviation). T2 values were 154 +/- 11 milliseconds, 342 +/- 53 milliseconds, and 285 +/- 167 milliseconds, respectively. Total choline concentration was lower in patients (mean, 1.5 mmol/L; range, 0.9-2.1 mmol/L) than controls (mean, 4.4 mmol/L; range, 3.2-5.7 mmol/L; P = 4 x 10(-)(5)). Total creatine concentration was likewise reduced in patients (mean, 1.1 mmol/L; range, undetectable -2.7 mmol/L) compared with controls (mean, 3.6 mmol/L; range, 2.5-4.7 mmol/L; P = 1.6 x 10(-)(4)). The myo-inositol signal normalized to the water reference was also lower in patients than controls (P = 4 x 10(-)(5)). CONCLUSIONS: Testicular metabolite concentrations, measured by proton spectroscopy at 3 T, may be valuable as noninvasive biomarkers of spermatogenesis.

PURPOSE: To characterize recent magnetic resonance imaging (MRI) technical development and innovation based on data regarding MRI-related patents awarded in 2016. METHODS: The US Patent and Trademark Office website was searched for patents awarded in 2016 and an abstract containing "magnetic resonance." Patent characteristics were summarized. An MRI physicist classified patents' themes. RESULTS: A total of 423 MRI-related patents were awarded in 2016. Among these, 29% had 1 inventor, 24% had 2 inventors, and 47% had >/=2 inventors. Mean interval between patents being filed and awarded was 1389 +/- 559 days (range: 167-4029). Most common countries of patents' first assignee were USA (40%), Germany (24%), Netherlands (10%), and Japan (10%). In all, 3% included assignees with different countries (most common collaborators USA and Germany). Patents' first assignee had an industry affiliation in 76% vs an academic affiliation in 21% (4% indeterminate); and 3% had industry-academia collaboration. Patents' most common themes were coils (n = 77), sequence design (n = 65), and noncoil scanner hardware (n = 41). These top themes were similar for USA, international, and industry-based patents; however, for academic-based patents, the most common themes were sequence design, reconstruction, and exogenous agents. Less common themes included image analysis, postprocessing, spectroscopy, relaxometry, diffusion, motion correction, radiation therapy, implants, wireless devices, and positron emission tomography-MRI. CONCLUSION: Most MRI-related patents were by non-US inventors. A large majority had industry affiliation; minimal industry-academic collaboration was observed. Patents from industry and academic inventors had distinct top focuses: hardware and software, respectively. Awareness of the most recent years' MRI patents may provide insights into forthcoming clinical translations and help guide ongoing research and entrepreneurism.

OBJECTIVE: To determine if multiparametric MRI (mpMRI) identifies significant apical disease, thereby informing decisions regarding preservation of the membranous urethra. MATERIALS AND METHODS: Men undergoing radical prostatectomy between January 2012 and June 2016 who underwent a 12-core transrectal-ultrasound guided systematic biopsy, preoperative 3-T MRI, and sectioning of the prostate specimen with tumor foci mapping were extracted from a single surgeon's prospective longitudinal outcomes database. Apical systematic biopsy vs. mpMRI lesion were compared for predicting aggressive tumor in the prostatic apex defined as Prostate Cancer Grade Group >1. RESULTS: Of the 100 men who met eligibility criteria, 43 (43%) exhibited aggressive prostate cancer in the distal 5mm of the apex. A Likert score > 2 in the apical one-third of the prostate was found to be more reliable than any cancer found on apical systematic biopsy at detecting aggressive cancer in the apex. On multivariate regression that included Likert score in the apex, age, PSA, prostate size, and presence of any cancer on apical biopsy, only Likert score (p=.005) and PSA (p=.025) were significant and independent predictors of aggressive cancer in the distal apex. CONCLUSION: MRI is superior to systematic biopsy at identifying aggressive prostate cancer within the distal prostatic apex and may be useful for planning the extent of apical preservation during prostatectomy.

This article reviews basic concepts of report documentation for abdominal imaging examinations, focusing on practical elements for ensuring appropriate physician reimbursement. Nuances of abdominal radiography, CT, MRI, and ultrasonography codes are highlighted. Special considerations for the coding of 3D-rendering and contrast administration are also described. Greater abdominal radiologist awareness of these codes and their reporting requirements can help ensure proper documentation within radiology reports, thereby optimizing legitimate reimbursement.