Faculty Bibliography

BACKGROUND: The purpose of this study was to see if 3-dimensional (3D) magnetic resonance imaging (MRI) could improve our understanding of rotator cuff tendon tear shapes. We believed that 3D MRI would be more accurate than two-dimensional (2D) MRI for classifying tear shapes. METHODS: We performed a retrospective review of MRI studies of patients with arthroscopically proven full-thickness rotator cuff tears. Two orthopedic surgeons reviewed the information for each case, including scope images, and characterized the shape of the cuff tear into crescent, longitudinal, U- or L-shaped longitudinal, and massive type. Two musculoskeletal radiologists reviewed the corresponding MRI studies independently and blind to the arthroscopic findings and characterized the shape on the basis of the tear's retraction and size using 2D MRI. The 3D reconstructions of each cuff tear were reviewed by each radiologist to characterize the shape. Statistical analysis included 95% confidence intervals and intraclass correlation coefficients. RESULTS: The study reviewed 34 patients. The accuracy for differentiating between crescent-shaped, longitudinal, and massive tears using measurements on 2D MRI was 70.6% for reader 1 and 67.6% for reader 2. The accuracy for tear shape characterization into crescent and longitudinal U- or L-shaped using 3D MRI was 97.1% for reader 1 and 82.4% for reader 2. When further characterizing the longitudinal tears as massive or not using 3D MRI, both readers had an accuracy of 76.9% (10 of 13). The overall accuracy of 3D MRI was 82.4% (56 of 68), significantly different (P = .021) from 2D MRI accuracy (64.7%). CONCLUSION: Our study has demonstrated that 3D MR reconstructions of the rotator cuff improve the accuracy of characterizing rotator cuff tear shapes compared with current 2D MRI-based techniques.

INTRODUCTION: There is increasing interest in using imaging in the detection and localization of prostate cancer (PCa). Both multiparametric magnetic resonance imaging (mpMRI) and HistoScanning (HS) have been independently evaluated in the detection and localization of PCa. We undertook a prospective, blinded comparison of mpMRI and HS for cancer localization among men undergoing radical prostatectomy. METHODS: Following approval by the institutional review board, men scheduled to undergo radical prostatectomy, who had previously undergone mpMRI at our institution, were offered inclusion in the study. Those consenting underwent preoperative HS following induction of anesthesia; mpMRI, HS, and surgical step-section pathology were independently read by a single radiologist, urologist, and pathologist, respectively, in a blinded fashion. Disease maps created by each independent reader were compared and evaluated for concordance by a 5 persons committee consisting of 2 urologists, 2 pathologists, and 1 radiologist. Logistic regression for correlated data was used to assess and compare mpMRI and HS in terms of diagnostic accuracy for cancer detection. Generalized estimating equations based on binary logistic regression were used to model concordance between reader opinion and the reference standard assessment of the same lesion site or region as a function of imaging modality. RESULTS: Data from 31/35 men enrolled in the trial were deemed to be evaluable. On evaluation of cancer localization, HS identified cancer in 36/78 (46.2%) regions of interest, as compared with 41/78 (52.6%) on mpMRI (P = 0.3968). The overall accuracy, positive predictive value, negative predictive value, and specificity for detection of disease within a region of interest were significantly better with mpMRI as compared with HS. HS detected 36/84 (42.9%) cancer foci as compared with 42/84 (50%) detected by mpMRI (P = 0.3678). Among tumors with Gleason score>6, mpMRI detected 19/22 (86.4%) whereas HS detected only 11/22 (50%, P = 0.0078). Similarly, among tumors>10mm in maximal diameter, mpMRI detected 28/34 (82.4%) whereas HS detected only 19/34 (55.9%, P = 0.0352). CONCLUSION: In our institution, the diagnostic accuracy of HS was inferior to that of mpMRI in PCa for PCa detection and localization. Although our study warrants validation from larger cohorts, it would suggest that the HS protocol requires further refinement before clinical implementation.

BACKGROUND: To assess associations between whole-lesion apparent diffusion coefficient (ADC) metrics and pathologic findings of Likert score 3 prostate lesions at MRI/ultrasound fusion targeted biopsy. METHODS: This retrospective Institutional Review Board-approved study received a waiver of consent. We identified patients receiving a highest lesion score of 3 on 3 Tesla multiparametric MRI reviewed by a single experienced radiologist using a 5-point Likert scale and who underwent fusion biopsy. A total of 188 score 3 lesions in 158 patients were included. Three-dimensional volumes-of-interest encompassing each lesion were traced on ADC maps. Logistic regression was used to predict biopsy results based on whole-lesion ADC metrics and patient biopsy history. Biopsy yield was compared between metrics. RESULTS: By lesion, targeted biopsy identified tumor in 22.3% and Gleason score (GS) > 6 tumor in 8.5%, although results varied by biopsy history: biopsy-naive (n = 80), 20.0%/8.8%; prior negative biopsy (n = 53), 9.4%/1.9%; prior positive biopsy (n = 55): 40.0%/14.5%. Biopsy history, whole-lesion mean ADC, whole-lesion ADC10-25 , and whole-lesion ADC25-50 were each significantly associated with tumor or GS > 6 tumor at fusion biopsy (P 6 tumor, which was significantly higher (P < 0.001) than specificity of PSA (17.5%) at identical sensitivity. CONCLUSION: For score 3 lesions in patients without prior negative biopsy, whole-lesion ADC metrics help detect GS > 6 cancer while avoiding negative biopsies. However, deferral of fusion biopsy may be considered for score 3 lesions in patients with prior negative biopsy (without applying whole-lesion ADC metrics) given exceedingly low ( approximately 2%) frequency of GS > 6 tumor in this group. J. Magn. Reson. Imaging 2015.