Faculty Bibliography

Purpose To test the impact of existing Prostate Imaging Reporting and Data System (PI-RADS) version 2 (V2) decision rules, as well as of proposed adjustments to these decision rules, on detection of Gleason score (GS) 7 or greater (GS >/=7) prostate cancer. Materials and Methods Two radiologists independently provided PI-RADS V2 scores for the dominant lesion on 343 prostate magnetic resonance (MR) examinations. Diagnostic performance for GS >/=7 tumor was assessed by using MR imaging-ultrasonography fusion-targeted biopsy as the reference. The impact of existing PI-RADS V2 decision rules, as well as a series of exploratory proposed adjustments, on the frequency of GS >/=7 tumor detection, was evaluated. Results A total of 210 lesions were benign, 43 were GS 6, and 90 were GS >/=7. Lesions were GS >/=7 in 0%-4.1% of PI-RADS categories 1 and 2, 11.4%-27.1% of PI-RADS category 3, 44.4%-49.3% of PI-RADS category 4, and 72.1%-73.7% of PI-RADS category 5 lesions. PI-RADS category 4 or greater had sensitivity of 78.9%-87.8% and specificity of 75.5%-79.1 for detecting GS >/=7 tumor. The frequency of GS >/=7 tumor for existing PI-RADS V2 decision rules was 30.0%-33.3% in peripheral zone (PZ) lesions upgraded from category 3 to 4 based on dynamic contrast enhancement (DCE) score of positive; 50.0%-66.7% in transition zone (TZ) lesions upgraded from category 3 to 4 based on diffusion-weighted imaging (DWI) score of 5; and 71.7%-72.7% of lesions in both zones upgraded from category 4 to 5 based on size of 15 mm or greater. The frequency of GS >/=7 tumor for proposed adjustments to the decision rules was 30.0%-60.0% for TZ lesions upgraded from category 3 to 4 based on DWI score of 4; 33.3%-57.1% for TZ lesions upgraded from category 3 to 4 based on DCE score of positive when incorporating new criteria (unencapsulated sheetlike enhancement) for DCE score of positive in TZ; and 56.4%-61.9% for lesions in both zones upgraded from category 4 to 5 based on size of 10-14 mm. Other proposed adjustments yielded GS >/=7 tumor in less than 15% of cases for one or more readers. Conclusion Existing PI-RADS V2 decision rules exhibited reasonable performance in detecting GS >/=7 tumor. Several proposed adjustments to the criteria (in TZ, upgrading category 3 to 4 based on DWI score of 4 or modified DCE score of positive; in PZ or TZ, upgrading category 4 to 5 based on size of 10-14 mm) may also have value for this purpose. (c) RSNA, 2016 Online supplemental material is available for this article.

PURPOSE: The aim of this study was to evaluate the feasibility of using Twitter polls to assess public opinion regarding session content at a national specialty society meeting. METHODS: Twitter polls allow users to embed multiple-choice questions within tweets and automatically aggregate responses. Two radiologists attending the 2016 annual meeting of the ACR posted a Twitter poll containing the hashtag #ACR2016 during 10 meeting sessions addressing socioeconomics/advocacy, patient experience, and social media/informatics (20 polls total). Each poll contained a question asking for an opinion regarding the session's content. Polls were open for responses for 24 hours. RESULTS: The average number of responses per poll was significantly higher for the user with the larger number of Twitter followers (24.3 +/- 14.4 versus 11.2 +/- 9.8, P = .015). A total of 57% of respondents agreed that radiologists' payments should shift to value-based payments, and 86% agreed that radiologists should routinely survey their patients to monitor quality; however, 83% disagreed with basing physician payments on patient satisfaction scores. A total of 85% disagreed that the artificial intelligence supercomputer Watson will entirely replace radiologists. A total of 76% agreed that social media can drive business at less cost than standard marketing. A total of 56% agreed with the direction of the ACR's advocacy and regulatory efforts, whereas 74% considered the ACR's advocacy efforts to be moderately or very useful for their practice. A total of 50% planned to change their practice on the basis of keynote remarks by Dr Ezekiel Emanuel. CONCLUSIONS: Twitter polls provide a free and easy infrastructure to potentially capture global public sentiment during the course of a medical society meeting. Their use may enrich and promote discussions of key session content.

OBJECTIVE: The purpose of this article is to compare radiologists', referring physicians', and patients' interpretations of expressions within radiology reports to describe findings of likely low clinical significance. SUBJECTS AND METHODS: Surveys were completed by abdominal radiologists (n = 13), physicians referring patients for abdominal CT (n = 59), and outpatients awaiting imaging (n = 51) at a large urban academic medical center. Surveys presented 10 expressions for describing an incidental 5-mm liver lesion and asked respondents to select from a list of choices their perceived likelihood that the lesion represented malignancy. Radiologists and referrers were asked supplemental questions. RESULTS: Compared with radiologists' concern, referrers' and patients' concerns were higher for four and seven of the 10 expressions. Only the expression "benign cyst" was associated with no concern in all groups; "most likely a cyst" and "too small to characterize" were associated with median levels of concern of 0% for radiologists, > 0% to 1% for referrers, and > 2% to 5% for patients. Expressions containing the phrase "not excluded" had the highest concern in all groups. Referrers' likelihood of ordering follow-up imaging varied widely for the expressions (e.g., "benign cyst," 2%; "cyst," 22%; "most likely a cyst," 46%; "most likely a cyst, although tumor not excluded," 75%). Overall, the preferred phrase for a 5-mm liver lesion with benign features in normal-risk patients was "cyst" among radiologists and "benign cyst" among referrers. Seventy-six percent of referring physicians thought that radiology reports should indicate whether follow-up imaging is recommended for such lesions. CONCLUSION: Ambiguity in radiologists' language for incidental low-risk findings may contribute to increased patient anxiety and follow-up testing, warranting greater radiologist attention and potentially new practice or reporting strategies.

PURPOSE: To assess the effects of temporal resolution (RT ) in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) on qualitative tumor detection and quantitative pharmacokinetic parameters in prostate cancer. MATERIALS AND METHODS: This retrospective Institutional Review Board (IRB)-approved study included 58 men (64 +/- 7 years). They underwent 3T prostate MRI showing dominant peripheral zone (PZ) tumors (24 with Gleason >/= 4 + 3), prior to prostatectomy. Continuously acquired DCE utilizing GRASP (Golden-angle RAdial Sparse Parallel) was retrospectively reconstructed at RT of 1.4 sec, 3.7 sec, 6.0 sec, 9.7 sec, and 14.9 sec. A reader placed volumes-of-interest on dominant tumors and benign PZ, generating quantitative pharmacokinetic parameters (ktrans , ve ) at each RT . Two blinded readers assessed each RT for lesion presence, location, conspicuity, and reader confidence on a 5-point scale. Data were assessed by mixed-model analysis of variance (ANOVA), generalized estimating equation (GEE), and receiver operating characteristic (ROC) analysis. RESULTS: RT did not affect sensitivity (R1all : 69.0%-72.4%, all Padj = 1.000; R1GS>/=4 + 3 : 83.3-91.7%, all Padj = 1.000; R2all : 60.3-69.0%, all Padj = 1.000; R2GS>/=4 + 3 : 58.3%-79.2%, all Padj = 1.000). R1 reported greater conspicuity of GS >/= 4 + 3 tumors at RT of 1.4 sec vs. 14.9 sec (4.29 +/- 1.23 vs. 3.46 +/- 1.44; Padj = 0.029). No other tumor conspicuity pairwise comparison reached significance (R1all : 2.98-3.43, all Padj >/= 0.205; R2all : 2.57-3.19, all Padj >/= 0.059; R1GS>/=4 + 3 : 3.46-4.29, all other Padj >/= 0.156; R2GS>/=4 + 3 : 2.92-3.71, all Padj >/= 0.439). There was no effect of RT on reader confidence (R1all : 3.17-3.34, all Padj = 1.000; R2all : 2.83-3.19, all Padj >/= 0.801; R1GS>/=4 + 3 : 3.79-4.21, all Padj = 1.000; R2GS>/=4 + 3 : 3.13-3.79, all Padj = 1.000). ktrans and ve of tumor and benign tissue did not differ across RT (all adjusted P values [Padj ] = 1.000). RT did not significantly affect area under the curve (AUC) of Ktrans or ve for differentiating tumor from benign (all Padj = 1.000). CONCLUSION: Current PI-RADS recommendations for RT of 10 seconds may be sufficient, with further reduction to the stated PI-RADS preference of RT