Diagnostic Yield and Complication Rate in Percutaneous Needle Biopsy of Renal Hilar Masses With Comparison With Renal Cortical Mass Biopsies in a Cohort of 195 Patients.

OBJECTIVE: The objective of this study was to compare diagnostic yield and complication rate in needle biopsy (NB) of renal hilar and cortical masses. MATERIALS AND METHODS: With institutional review board approval, we retrospectively studied 195 patients (120 men, 75 women; mean age ± SD, 67 ± 13 years old) who underwent ultrasound-guided renal mass NB between January 2013 and December 2017. Operator years of experience, biopsy technique (coaxial or successive), needle gauge (22-gauge fine-needle aspiration, 18-gauge core-needle, or both), number of passes, postprocedural complication, and histopathologic diagnoses were recorded. A radiologist who was blinded to histopathologic diagnoses recorded mass location (upper pole, interpolar region, lower pole) and percentage of hilar involvement. Comparisons were performed using independent t and chi-square tests. RESULTS: Of the masses biopsied, 5.6% (11/195) were 100% hilar (mean hilar involvement, 20.8% ± 29.8%; range, 0-100%). Mean lesion size was 44 ± 27 mm (range, 12-157 mm). NB diagnosis was established in 84.6% (165/195) of masses, and 15.4% (30/195) of biopsies were inconclusive, with no association with size (p = 0.55) or percentage of hilar involvement (p = 0.756). In the purely hilar masses, diagnosis was established in 72.7% (8/11) compared with 85.3% (157/184) with any cortical involvement (p = 0.265). There was no association between diagnosis and operator years of experience, biopsy technique, needle gauge, or number of passes (p > 0.05). Bleeding occurred after biopsy in 7.7% (15/195) of cases, was associated with percentage of hilar involvement (39.3% ± 44.9% vs 19.3% ± 27.8%; p = 0.012), and was more common in purely hilar masses (36.4% [4/11] vs 5.6% [11/195]; p < 0.001). Complications were not associated with any other feature (p > 0.05). CONCLUSION: Percutaneous biopsy of renal hilar masses is technically feasible with diagnostic yield similar to that of cortical masses but with postprocedural bleeding more often than what is seen with cortical masses.

Evaluation of MRI for diagnosis of extraprostatic extension in prostate cancer.

PURPOSE: To assess the ability of magnetic resonance imaging (MRI) to diagnose extraprostatic extension (EPE) in prostate cancer. MATERIALS AND METHODS: With Institutional Review Board (IRB) approval, 149 men with 170 ≥0.5 mL tumors underwent preoperative 3T MRI followed by radical prostatectomy (RP) between 2012-2015. Two blinded radiologists (R1/R2) assessed tumors using Prostate Imaging Reporting and Data System (PI-RADS) v2, subjectively evaluated for the presence of EPE, measured tumor size, and length of capsular contact (LCC). A third blinded radiologist, using MRI-RP-maps, measured whole-lesion: apparent diffusion coefficient (ADC) mean/centile and histogram features. Comparisons were performed using chi-square, logistic regression, and receiver operator characteristic (ROC) analysis. RESULTS: The subjective EPE assessment showed high specificity (SPEC = 75.4/91.3% [R1/R2]), low sensitivity (SENS = 43.3/43.6% [R1/R2]), and area-under (AU) ROC curve = 0.67 (confidence interval [CI] 0.61-0.73) R1 and 0.61 (CI 0.53-0.70) R2; (k = 0.33). PI-RADS v2 scores were strongly associated with EPE (P < 0.001 / P = 0.008; R1/R2) with AU-ROC curve = 0.72 (0.64-0.79) R1 and 0.61 (0.53-0.70) R2; (k = 0.44). Tumors with EPE were larger (18.8 ± 7.8 [median 17, range 6-51] vs. 18.8 ± 4.9 [12, 6-28] mm) and had greater LCC (21.1 ± 14.9 [16, 1-85] vs. 13.6 ± 6.1 [11.5, 4-30] mm); P < 0.001 and 0.002, respectively. AU-ROC for size was 0.73 (0.64-0.80) and LCC was 0.69 (0.60-0.76), respectively. Optimal SENS/SPEC for diagnosis of EPE were: size ≥15 mm = 67.7/66.7% and LCC ≥11 mm = 84.9/44.8%. 10th -centile ADC and ADC entropy were both associated with EPE (P = 0.02 and < 0.001), with AU-ROC = 0.56 (0.47-0.65) and 0.76 (0.69-0.83), respectively. Optimal SENS/SPEC for diagnosis of EPE with entropy ≥6.99 was 63.3/75.0%. 25th -centile ADC trended towards being significantly lower with EPE (P = 0.06) with no difference in other ADC metrics (P = 0.25-0.88). Size, LCC, and ADC entropy improved sensitivity but reduced specificity compared with subjective analysis with no difference in overall accuracy (P = 0.38). CONCLUSION: Measurements of tumor size, capsular contact, and ADC entropy improve sensitivity but reduce specificity for diagnosis of EPE compared to subjective assessment. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:176-185.

Diagnostic Accuracy of Qualitative and Quantitative Computed Tomography Analysis for Diagnosis of Pathological Grade and Stage in Upper Tract Urothelial Cell Carcinoma.

OBJECTIVE: The aim of this study was to compare grade and stage of upper tract urothelial cell carcinoma (UCC) using computed tomography. MATERIALS AND METHODS: With institutional review board approval, 48 patients with 49 UCC (44 high grade and 5 low grade, 26 ≤ T1 and 23 ≥ T2) underwent nephroureterectomy and preoperative computed tomography between 2013 and 2015. Two blinded radiologists assessed for tumor appearance (filling defect/mass or wall thickening/stricture), margin (smooth or spiculated/irregular), texture (homogeneous, heterogeneous), hydronephrosis, and calcification. A third blinded radiologist established consensus. A fourth blinded radiologist measured size and first-order histogram texture features. Comparisons were performed using χ test, multivariable logistic regression, and receiver operator characteristic analysis. RESULTS: There was no difference in size of tumors compared by grade or stage (P = 0.80 and 0.13, respectively).Among subjective variables, only tumor texture was significantly different between low- and high-grade UCC (P = 0.03; κ = 0.45). Tumors characterized as spiculated/irregular margin (P = 0.003; 0.30) and heterogeneous (P < 0.001; κ = 0.45) were associated with T2 disease or higher.Entropy was greater in higher grade (6.23 ± 0.46 vs 5.72 ± 0.28) and T2 disease or higher (6.40 ± 0.33 vs 5.95 ± 0.48), (P = 0.03 and 0.02, respectively) with no differences in Kurtosis or Skewness (P > 0.05). Area under the receiver operator characteristic curve for entropy to diagnose high-grade and T2 tumors or higher was 0.83 (confidence interval, 0.64-1.0) and 0.79 (confidence interval 0.59-0.98), respectively. CONCLUSIONS: Heterogeneity, assessed qualitatively and quantitatively, is accurate for diagnosis of higher grade and stage of disease in upper tract UCC. Spiculated/irregular margins are also associated with T2 disease or higher.

Prognostic value of Prostate Imaging and Data Reporting System (PI-RADS) v. 2 assessment categories 4 and 5 compared to histopathological outcomes after radical prostatectomy.

PURPOSE: To assess Prostate Imaging and Data Reporting System (PI-RADS) v. 2 score 4/5 lesions compared to Gleason score (GS) and stage after radical prostatectomy (RP) and to validate the proposed 15-mm size threshold that differentiates category 4 versus 5 lesions. MATERIALS AND METHODS: With Institutional Review Board (IRB) approval, 140 men underwent 3T magnetic resonance imaging (MRI) and RP between 2012-2015. Two blinded radiologists: 1) assigned PI-RADS v. 2 scores, 2) measured tumor size on axial T2 -weighted-MRI, and 3) assessed for extraprostatic extension (EPE). Interobserver agreement was calculated and consensus diagnoses achieved through reference standard (MRI-RP maps). PI-RADS v. 2 scores and tumor size were compared to GS and stage using chi-square, analysis of variance (ANOVA), and receiver operating characteristic (ROC) curve analysis. RESULTS: In all, 80.7% (113/140) of tumors were category 4 (n = 45) or 5 (n = 68) lesions (κ = 0.45). Overall tumor size was 18.2 ± 7.7 mm and category 5 lesions were larger (22.6 ± 6.8 versus 11.5 ± 1.9 mm, P < 0.001). High-risk (GS ≥8) tumors were larger than low- and intermediate-risk tumors (P = 0.016) and were more frequently, but not significantly so, category 5 lesions (78.9% [15/19] vs. 22.1% [4/10], P = 0.18). 67.3% (76/113) of patients had EPE. Category 5 lesions were strongly associated with EPE (P < 0.0001). Area under the ROC curve for diagnosis of EPE by size was 0.74 (confidence interval 0.64-0.83), with size ≥15 mm yielding a sensitivity/specificity of 72.4/64.9%. Size improved sensitivity for diagnosis of EPE compared to subjective assessment (sensitivity/specificity ranging from 46.1-48.7%/70.3-86.5%, κ = 0.29) (P = 0.028). CONCLUSION: PI-RADS v. 2 category 5 lesions are associated with higher Gleason scores and EPE. A 15-mm size threshold is reasonably accurate for diagnosis of EPE with increased sensitivity compared to subjective assessment. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:257-266.

Is Ultrasound Useful for Further Evaluation of Homogeneously Hyperattenuating Renal Lesions Detected on CT?

OBJECTIVE: The purpose of this study was to evaluate the ability of ultrasound (US) to characterize hyperattenuating cysts detected as indeterminate hyperattenuating renal lesions on unenhanced and single phase enhanced CT. MATERIALS AND METHODS: A total of 107 consecutive homogeneously hyperattenuating renal lesions underwent gray-scale and Doppler US at our institution between 2010 and 2013. Two radiologists who were unaware of the final diagnosis retrospectively evaluated US images for visibility and diagnosis (simple cyst, intermediate complexity cyst, cystic or solid mass showing internal flow on Doppler US, or indeterminate). A third radiologist assessed lesion size, location, and distance to skin on CT and US. US visibility was compared using chi-square and independent t tests. Consensus US interpretation was compared with reference standard diagnoses, and accuracy for diagnosis of hyperattenuating cysts was tabulated. RESULTS: Mean lesion size ± SD was 20 ± 16 mm (range, 6-96 mm) and mean distance to skin on CT was 62 ± 25 mm (range, 18-125 mm). In all, 89.7% (96/107) of the lesions were visible on US, including all lesions that were 15 mm or larger. Nonvisible lesions were smaller than visible ones (10.0 ± 3.6 mm vs 20.7 ± 16.3 mm, p = 0.03) regardless of location (p > 0.05). CT overestimated lesion distance to skin compared with US (46.6 ± 18.6 mm, p < 0.001). Final diagnoses for US visible lesions (n = 96) were hyperattenuating cyst (n = 66), Bosniak IIF cyst (n = 13), and cystic or solid neoplasm (n = 15); two patients were lost to follow-up. Of the 66 hyperattenuating cysts, 54 (81.8%) appeared as simple cysts on US with sensitivity and specificity for diagnosis of hyperattenuating cyst of 81.8% (95% CI, 75.6-84.3%) and 92.9% (95% CI, 78.1-98.7%), respectively. The other 12 (18.2%) hyperattenuating cysts appeared complex. Two of the 13 Bosniak IIF lesions were incorrectly classified as simple cysts with US. Including the 11 (10%) nonvisible lesions reduced sensitivity and specificity for diagnosis of hyperattenuating cyst to 73.0% (95% CI, 66.9-75.9%) and 89.7% (95% CI, 74.2-97.2%), respectively. CONCLUSION: US can further characterize hyperattenuating cysts presenting as indeterminate hyperattenuating renal lesions on CT in the majority of cases.

Evaluation of apparent diffusion coefficient and MR volumetry as independent associative factors for extra-prostatic extension (EPE) in prostatic carcinoma.

BACKGROUND: To assess mean apparent diffusion coefficient (ADC) and MR-derived tumor volume (Vt) as associative factors for extra-prostatic extension (EPE) in prostate cancer (PCa). METHODS: With institutional review board approval, 73 consecutive patients diagnosed with PCa at trans-rectal ultrasound biopsy underwent preoperative multi-parametric (T2W+DWI+DCE) 3 Tesla MRI before radical prostatectomy between 2012 and 2014; 52% (38/73) patients had EPE. Clinical parameters including: age, prostate serum antigen (PSA), digital rectal examination (DRE) and percentage positive cores (PPC) were recorded. Two blinded radiologists subjectively evaluated for EPE using PI-RADS with T2W-MRI. A third blinded radiologist recorded: mean ADC (mm(2) /s) of tumor and tumor volume on ADC and T2W (derived from planar volumetry). VtMAX (the largest volume on ADC or T2W) was documented. Multivariate and receiver operator characteristic analyses were performed. RESULTS: There were no significant differences in age, DRE, or Gleason score between groups (P = 0.52, 0.06, 0.61, 0.36). PSA approached significance being higher with EPE (12.9 ± 12.6 versus 8.2 ± 7.4; P = 0.06). PPC was higher with EPE (60.9 ± 21.9% versus 38.3 ± 21.6%; P < 0.01) with an area under the curve (AUC) of 0.78 and sensitivity/specificity = 75.7/75% when PPC ≥ 45%. AUC for T2W-MRI was 0.46-0.51 with sensitivity/specificity = 40.0-42.9/48.6-57.1% (R1, R2). Inter-observer agreement was fair, k = 0.39. There was no difference in mean ADC between groups (0.89 ± 0.25 versus 0.88 ± 0.19 [EPE] mm(2) /s), P = 0.70. T2W-Vt, ADC-Vt, and VtMAX were larger with EPE (5.1 ± 7.4, 5.8 ± 6.5, 6.3 ± 7.4 cm(3) versus 1.6 ± 1.8, 1.8 ± 1.3, 2.1 ± 1.8), P < 0.01. VtMAX AUC was 0.77 with sensitivity/specificity = 78.4/73.5% when VtMAX ≥ 2.1 cm(3) which outperformed all other parameters (P > 0.05) except PPC (P = 0.6) for the diagnosis EPE. CONCLUSION: MR volumetry and percentage of positive core biopsies are associated with EPE; whereas, in this study, other clinical and MR parameters including mean ADC and subjective T2W-MR analysis were not useful for assessment of EPE.

Intracellular lipid in clear cell renal cell carcinoma tumor thrombus and metastases detected by chemical shift (in and opposed phase) MRI: radiologic-pathologic correlation.

BACKGROUND: Clear cell renal cell carcinoma (RRC) characteristically contain intracellular lipid which is also detectable in tumor thrombus and metastases. PURPOSE: To assess the incidence of intracellular lipid in clear cell RCC metastases and tumor thrombus using chemical shift MRI. MATERIAL AND METHODS: With REB approval, 33 consecutive patients with clear cell RCC and tumor thrombus/metastatic disease underwent magnetic resonance imaging (MRI) over a 10-year period. Diagnosis was established by histopathology for tumor thrombi (n = 25) and metastases (n = 15) or growth for metastases (n = 14). Two blinded radiologists independently assessed for a signal intensity (SI) drop at chemical shift MRI (indicative of intracellular lipid) and a third radiologist established consensus. Chemical shift SI (CS-SI) index ([SItumorIP - SItumorOP]/SITumorIP x 100) was calculated. Inter-observer agreement was assessed using intra-class correlation (ICC) and tests of association were performed using the Chi-square test and Spearman correlation. RESULTS: Using CS-MRI, intracellular lipid was detected in 36.4% of clear cell RCC, with moderate agreement, (ICC = 0.5). Intracellular lipid was detected in 20% of tumor thrombi and 20% of metastases with strong agreement (ICC = 0.73). Intracellular lipid within tumor thrombi/metastases was not associated with lipid within the primary tumor (P = 0.09). There was a correlation in CS-SI index between primary tumor and thrombi/metastases when lipid was detected in both lesions (r = 0.91, P = 0.005); however, there was no correlation when lipid was not detected in both lesions (r = -0.09, P = 0.72). CONCLUSION: The presence of intracellular lipid in tumor thrombus and metastases from clear cell RCC is uncommon and, is not necessarily associated with lipid within the primary tumor at chemical shift MRI.

Multi-echo gradient recalled echo imaging of the pelvis for improved depiction of brachytherapy seeds and fiducial markers facilitating radiotherapy planning and treatment of prostatic carcinoma.

PURPOSE: MR localization of implanted devices for radiotherapy (RT) in prostatic carcinoma is critical for treatment planning. This clinical note studies the application of a multi-echo gradient recalled echo (GRE) pulse sequence with sum of squares echo combination (ME GRE) to enhance detection of seeds and fiducials. MATERIALS AND METHODS: Fifteen patients who underwent MRI using fast spin echo (FSE), single-echo and ME GRE over a 9-month period were retrospectively evaluated by two readers who assessed overall image quality, depiction of seeds/fiducials and image sharpness using a 5-point scale (1 = poor, 2 = suboptimal, 3 = adequate, 4 = above average, 5 = excellent). Image scores were compared using the Wilcoxon sign rank test. RESULTS: In all 15 patients, both readers rated the depiction of seeds/fiducials with ME GRE as excellent. In all 15 patients, overall image quality and image sharpness with ME GRE was rated as excellent by reader 1. In 12/15 patients, overall image quality and image sharpness with ME GRE was rated as excellent and in the other patients above average by reader 2. There was a difference in depiction of seeds/fiducials comparing GRE to FSE (P < 0.001) and ME to single echo GRE (P < 0.001). Overall image quality and sharpness was higher with ME compared with single echo GRE (P < 0.001) and similar to FSE (P = 0.26 and P = 0.16). CONCLUSION: Multi-echo GRE provides better detection of implanted seeds and fiducial markers when compared with both FSE and single-echo GRE potentially improving RT treatment planning for prostate carcinoma.

Does a cleansing enema improve image quality of 3T surface coil multiparametric prostate MRI?

PURPOSE: To assesses the utility of a preparatory enema in the interpretation of prostate multiparametric (MP) magnetic resonance imaging (MRI). MATERIALS AND METHODS: Under a waiver from the Institutional Review Board (IRB), 32 patients without bowel preparation and 28 patients who underwent a self-administered enema were imaged consecutively with 3T MP-MRI over 6 months. Two blinded radiologists independently assessed image quality on T2 -weighted (T2 W), trace b 1000 mm(2) /sec echo-planar (EPI) and apparent-diffusion coefficient (ADC) and assessed for motion/blur on T2 W and distortion/blur on EPI and ADC. Radiologists also quantified rectal stool and gas. A third blinded radiologist generated contrast curves from dynamic contrast-enhanced (DCE) data at six locations and measured the number of corrupted data points, defined as >10% aberrant signal intensity change. Subjective scores were compared using Wilcoxon sign rank test. Rectal contents were correlated to artifact using Spearman correlation. Contrast curves were evaluated with independent t-tests. RESULTS: There was no difference in image quality on T2 W (P = 0.66-0.74), EPI (P = 0.13-0.36) or ADC (P = 0.49-0.59). There was less rectal stool in the enema group (P = 0.004) and amount of stool correlated with motion artifact on T2 W (r = 0.23, P = 0.02); however, there was no difference in motion artifact between groups (P = 0.47-0.94). Only a minority of patients in the non-enema group had moderate or large amounts of stool (16%) and none of these patients had severe or extensive artifact on T2 . There was less rectal gas in the enema group (P = 0.002); however, amount of gas did not correlate with distortion artifact on EPI or ADC (P = 0.17-0.41) and there was no difference in blur (P = 0.41-0.91) or distortion (P = 0.31-0.99) on EPI or ADC between groups. There was no difference in corrupted data points on DCE (P = 0.46). CONCLUSION: In this study the use of a preparatory enema did not improve image quality or reduce artifact in prostate MP-MRI.

Solid Renal Cell Carcinoma Measuring Water Attenuation (-10 to 20 HU) on Unenhanced CT.

OBJECTIVE: The objectives of this study were to evaluate the incidence of solid renal cell carcinoma (RCC) with attenuation similar to that of water (-10 to 20 HU) on unenhanced CT and to examine imaging features that can allow RCC to be differentiated from simple cysts. MATERIALS AND METHODS: We performed an enriched quantitative and qualitative retrospective analysis of consecutive patients who underwent unenhanced CT before resection of solid (noncystic and nonnecrotic) renal masses measuring < 5 cm from 2008 to 2013. In all, 93 patients with 96 tumors (55 clear cell, 27 papillary, and 14 chromophobe) were evaluated with unenhanced CT. Attenuation was measured at three standardized levels and compared using the Kruskal-Wallis test. Two radiologists independently assessed calcification, margin (smooth or irregular), and heterogeneity (homogeneous or heterogeneous). Results were compared using the chi-square test with Bonferroni correction. RESULTS: Mean ± SD attenuation values were 31.8 ± 9.6 HU (range, 11-63 HU) overall, 29.9 ± 8.8 HU (range, 11.0-49.0 HU) for clear cell tumors, 34.6 ± 10.3 HU (range, 20.3-63.0 HU) for papillary tumors, and 35.5 ± 9.2 HU (range, 20.7-47 HU) for chromophobe tumors (p = 0.06). Eight clear cell RCCs had attenuation similar to that of water (15.7 ± 2.4 HU; range, 11-18.7 HU). There was no significant difference in calcification or margin among different types of tumors (p = 0.91 and p = 0.55, respectively). Chromophobe tumors were more likely to be homogeneous (p < 0.001). Interobserver agreement was moderate to very good (κ = 0.91 for calcification, κ = 0.55 for margin, and κ = 0.44 for heterogeneity). All eight clear cell RCCs with attenuation similar to that of water were considered heterogeneous by both readers. Irregular margins were identified in three of these eight tumors by reader 1 and four of eight tumors by reader 2. CONCLUSION: A minority of solid RCCs have attenuation similar to that of water on unenhanced CT. In this study, all such tumors were of the clear cell subtype and qualitatively heterogeneous, suggesting they can be distinguished from simple cysts on unenhanced CT.

Diagnosis of Sarcomatoid Renal Cell Carcinoma With CT: Evaluation by Qualitative Imaging Features and Texture Analysis.

OBJECTIVE: The objective of our study was to determine whether CT findings, including texture analysis, can differentiate sarcomatoid renal cell carcinoma (RCC) from clear cell RCC. MATERIALS AND METHODS: A retrospective case-control study was performed of consecutive patients with a histologic diagnosis of sarcomatoid RCC (n = 20) and clear cell RCC (n = 25) who underwent preoperative CT over a 3-year period. The CT images were independently reviewed by two blinded abdominal radiologists; they evaluated the following: tumor heterogeneity, tumor margin, calcification, intratumoral neovascularity, peritumoral neovascularity, renal sinus invasion, renal vein invasion, and adjacent organ invasion. Interobserver agreement was assessed using the Cohen kappa coefficient, and results were compared between groups using an independent Student t test and the chi-square test with a Bonferroni correction. For texture analysis, gray-level co-occurrence and run-length matrix features were extracted and compared using Mann-Whitney U tests. ROC curves for each tumor were constructed, and AUCs were calculated. RESULTS: Overall, sarcomatoid RCCs were larger than clear cell RCCs, measuring 77 ± 27 mm (mean ± SD) compared with 50 ± 29 mm (p = 0.003), respectively; however, there was no difference in tumor size between the tumors that were compared using texture analysis or subjective analysis (p = 0.06 and 0.03, respectively). From the subjective analysis, only peritumoral neovascularity (readers 1 and 2: 70% and 70% sarcomatoid RCCs vs 0% and 41.6% clear cell RCCs, respectively; p = 0.001) and the size of the peritumoral vessels (p < 0.001) differed between sarcomatoid RCCs and clear cell RCCs, and interobserver agreement was fair (κ = 0.38). Other subjective imaging features did not differ between the tumors (p > 0.005). There was greater run-length nonuniformity and greater gray-level nonuniformity in sarcomatoid RCCs than in clear cell RCCs (p = 0.03 and p = 0.04, respectively). The combined textural features identified sarcomatoid RCC with an AUC of 0.81 ± 0.08 (standard error) (p < 0.0001). CONCLUSION: Large tumor size, the presence of peritumoral neovascularity, and larger peritumoral vessels are features that are more commonly associated with sarcomatoid RCCs than with clear cell RCCs. Sarcomatoid RCCs are also more heterogeneous by texture analysis than clear cell RCCs.

Nephrogenic systemic fibrosis: a report of 29 cases.

OBJECTIVE: The purpose of this study was to determine the incidence of nephrogenic systemic fibrosis and its relation to renal failure and the administration of gadolinium-based contrast material at an academic medical center. MATERIALS AND METHODS: A dermatopathology database was searched to identify patients in whom nephrogenic systemic fibrosis was diagnosed. The medical records of these patients were reviewed. Renal function concurrent with any administration of gadolinium-based contrast material was assessed, as was patient outcome. A database of patients undergoing long-term dialysis was reviewed separately to determine how many had received gadolinium and the frequency of nephrogenic systemic fibrosis among these patients. RESULTS: Twenty-nine patients were found to have had nephrogenic systemic fibrosis between November 15, 1999, and December 31, 2006. It was known that gadolinium-based contrast material had been administered to 25 of these patients before diagnosis. All 29 patients had compromised renal function (27 had chronic renal failure, and two had acute renal failure). Determination of the temporal relation between gadolinium-based contrast administration and symptom onset often was difficult. Only eight patients had severe morbidity. Nephrogenic systemic fibrosis developed in 12 (2.9%) of 414 patients undergoing long-term dialysis who received gadolinium-based contrast material. CONCLUSION: We confirm the strong association between nephrogenic systemic fibrosis and gadolinium-based contrast administration. Although the use of high doses of gadolinium and the occurrence of chronic renal failure have been implicated in other reports, several of our patients received standard doses of gadolinium, and two had transient acute renal failure before diagnosis. Most patients had mild or moderate symptoms. Nephrogenic systemic fibrosis developed in 2.9% of patients undergoing long-term dialysis who received gadolinium-based contrast material but in none of the long-term dialysis patients who did not receive gadolinium-based contrast material.

Comparison of high-resolution T1W 3D GRE (LAVA) with 2-point Dixon fat/water separation (FLEX) to T1W fast spin echo (FSE) in prostate cancer (PCa).

PURPOSE: To compare T1-weighted (T1W) fast spin echo (FSE) to T1W 3-dimensional gradient recalled echo (LAVA) with fat water separation (FLEX) in prostate cancer (PCa). METHODOLOGY: With institutional review board waiver, 39 patients underwent 3-T magnetic resonance imaging including T1W LAVA FLEX (157s)/T1W FSE (316s). Two radiologists assessed (a) image quality/sharpness, (b) presence/severity of artifacts, and (c) skeletal (N=22)/nodal (N=9) metastases. Results were compared using Wilcoxon signed-rank test/receiver operator characteristic analysis. RESULTS: With T1W LAVA FLEX, image quality/sharpness improved (P<.001) with less motion (P=.002-.03) and no difference in phase-encoding artifact (P>.05). One patient had moderate fat/water swap. Detection of skeletal metastases was unchanged (P>.05) and nodal metastases either improved (P=.002) or were comparable (P=.16) using T1W LAVA FLEX. CONCLUSION: T1W LAVA FLEX improves image quality, lessens motion artifact, and is comparable or improves detection of metastases in PCa with reduction in acquisition time.

Efficacy and Accessibility of a Novel Liver Fibrosis Evaluation Program: Limited Abdominal Ultrasound with Concurrent Transient Elastography.

RATIONALE AND OBJECTIVES: To review sustainability and fair access related to setting up a centralized transient elastography (TE) program in the radiology department and to perform a quality assessment of a novel liver fibrosis evaluation program that combines TE with limited abdominal ultrasound (US). MATERIAL AND METHODS: As part of a quality assessment, a retrospective chart review was performed on 758 patients who underwent TE immediately after limited abdominal US of the liver over a 12-month period. The elastography results and sonographic findings were documented, including the number and type of lesions identified. In terms of fair access evaluation, the indication for TE and referring service was reviewed for each case. RESULTS: Most referrals were initiated by infectious disease (52.2% [396 of 758]) or gastroenterology (46.3% [351 of 758]) for patients with viral hepatitis (29.8% [226 of 758] for HBV and 52.2% [396 of 758] for HCV) and nonalcoholic steatohepatitis (11.9% [90 of 758]). Only 3.2% (24 of 758) of indications were outside the usual indications for which standardized values of TE were available. Most studies demonstrated minimal fibrosis (66.6% [510 of 766] ≤F1) or more advanced fibrosis (21.1% [162 of 766] ≥F3). Liver nodularity was observed in 63 cases, correlating to F2 fibrosis and above in 81.0% (51 of 63). US screening detected five new cases of hepatocellular carcinoma (HCC). CONCLUSIONS: This unique program allows fair access and ensures that referrals are requested for appropriate indications. Concurrent US confers many advantages including proper TE probe placement to optimize measurement success, characterization of sonographic features that correlate with advanced fibrosis, and provides an opportunity to screen for HCC, in a population which may not otherwise have access to standardized screening.

High-resolution T2-weighted (T2W) oblique plane turbo spin-echo (TSE) MRI for rectal adenocarcinoma staging.

PURPOSE: The purpose of this study was to determine the frequency/significance of incorrectly planned oblique T2-weighted (T2W) MRI of rectal adenocarcinoma. METHODS: Eighty-six consecutive patients underwent MRI for rectal cancer staging. Two radiologists evaluated oblique T2W imaging and tumor stage. RESULTS: A total of 71% of middle/high tumors had correctly planned oblique T2W-MRI. Thirteen of 14 low tumors (N=7) or tumors spanning at least two rectal segments (N=7) had incorrectly planned oblique T2W-MRI. The sensitivity/specificity of staging on correct compared to incorrect oblique T2W was: 88.9/50% (R1)/77.8/60% (R2) and 80/100% (R1)/60/80% (R2), (P=.54). Agreement was substantial, K=0.67. CONCLUSIONS: Oblique T2W-MRI is incorrectly performed in low tumors and those spanning multiple rectal segments. In this study, planning errors did not impact staging accuracy.

Use of a curved-array transducer to reduce interobserver variation in sonographic measurement of thyroid volume in healthy adults.

PURPOSE: Sonographic calculation of thyroid volume is used in the diagnosis and follow-up of thyroid diseases. Since the calculated volume of thyroid lobes is highly influenced by the longest (ie, craniocaudal) diameter, we examined whether using a curved-array transducer as opposed to a linear-array transducer to measure the craniocaudal diameter would reduce interobserver variation. METHODS: Three sonographers with different levels of expertise each used a 5-12-MHz linear-array transducer and a 2-5-MHz curved-array transducer to measure the craniocaudal diameter of both thyroid lobes of 25 healthy volunteers. On the basis of these measurements, thyroid lobe volumes were calculated. Single-factor analysis of variance was used to evaluate the interobserver variations between the measurements made by all 3 observers as well as between measurements taken by pairs of observers. A p value of less than 0.05 was considered significant. RESULTS: Using the linear-array transducer to measure the craniocaudal diameter resulted in significant interobserver variation in thyroid volume calculation (p = 0.02), whereas using the convex-array transducer did not. Using either transducer resulted in a highly significant interobserver variation in measurements of the craniocaudal diameter, although the variation was far more pronounced for measurements made with the linear-array transducer (p = 0.0005) than for those made with the curved-array transducer (p = 0.04). For both transducers, the interobserver variations were most pronounced between the most and the least experienced sonographers. CONCLUSIONS: To avoid significant interobserver variation in calculating thyroid lobe volume, we recommend using a curved-array transducer to measure the craniocaudal diameter of the thyroid lobes.