Intradermal Testing With Radiocontrast Media to Prevent Recurrent Adverse Reactions.

OBJECTIVE. Adverse drug reactions (ADRs) to radiocontrast media are a significant social and economic burden and are difficult to predict. Because some ADRs to radiocontrast media may be immunologically induced, a skin test with diluted 1:10 radiocontrast media has been used to predict ADRs. However, using this test in clinical practice is difficult because of its low sensitivity. SUBJECTS AND METHODS. This study enrolled 36 patients with a history of immediate ADR to radiocontrast media who visited the Allergy and Asthma Clinic of Severance Hospital from 2017 to 2018. Patients underwent intradermal testing (IDT) with five types of diluted (1:10) and undiluted radiocontrast media (iohexol, iobitridol, iopamidol, iopromide, and iodixanol). The IDT result was regarded as positive if at least one radiocontrast medium elicited a positive reaction. Positivity of IDT and sensitivity to the culprit radiocontrast medium were calculated and compared. For subsequent CT examinations with a radiocontrast medium, the contrast agent eliciting a negative skin reaction in IDT was selected, excluding the previous culprit radiocontrast medium. RESULTS. IDT positivity and sensitivity for the culprit radiocontrast medium at 1:10 dilution were 47.2% and 47.2%, respectively, whereas the positivity and sensitivity for the undiluted radiocontrast medium were 86.1% and 75.0%, respectively. The positivity and sensitivity were higher with frequent radiocontrast medium use or with severe reaction. Of 22 patients who underwent another CT examination with the contrast medium selected on the basis of IDT results, 21 (95.5%) did not experience an ADR. CONCLUSION. IDT to prevent ADR should be performed with undiluted radiocontrast medium. Selecting an alternative radiocontrast agent on the basis of IDT results can be clinically useful to prevent recurrent ADRs to radiocontrast media.

Focal Liver Lesions: Computer-aided Diagnosis by Using Contrast-enhanced US Cine Recordings.

Purpose To assess the performance of computer-aided diagnosis (CAD) systems and to determine the dominant ultrasonographic (US) features when classifying benign versus malignant focal liver lesions (FLLs) by using contrast material-enhanced US cine clips. Materials and Methods One hundred six US data sets in all subjects enrolled by three centers from a multicenter trial that included 54 malignant, 51 benign, and one indeterminate FLL were retrospectively analyzed. The 105 benign or malignant lesions were confirmed at histologic examination, contrast-enhanced computed tomography (CT), dynamic contrast-enhanced magnetic resonance (MR) imaging, and/or 6 or more months of clinical follow-up. Data sets included 3-minute cine clips that were automatically corrected for in-plane motion and automatically filtered out frames acquired off plane. B-mode and contrast-specific features were automatically extracted on a pixel-by-pixel basis and analyzed by using an artificial neural network (ANN) and a support vector machine (SVM). Areas under the receiver operating characteristic curve (AUCs) for CAD were compared with those for one experienced and one inexperienced blinded reader. A third observer graded cine quality to assess its effects on CAD performance. Results CAD, the inexperienced observer, and the experienced observer were able to analyze 95, 100, and 102 cine clips, respectively. The AUCs for the SVM, ANN, and experienced and inexperienced observers were 0.883 (95% confidence interval [CI]: 0.793, 0.940), 0.829 (95% CI: 0.724, 0.901), 0.843 (95% CI: 0.756, 0.903), and 0.702 (95% CI: 0.586, 0.782), respectively; only the difference between SVM and the inexperienced observer was statistically significant. Accuracy improved from 71.3% (67 of 94; 95% CI: 60.6%, 79.8%) to 87.7% (57 of 65; 95% CI: 78.5%, 93.8%) and from 80.9% (76 of 94; 95% CI: 72.3%, 88.3%) to 90.3% (65 of 72; 95% CI: 80.6%, 95.8%) when CAD was in agreement with the inexperienced reader and when it was in agreement with the experienced reader, respectively. B-mode heterogeneity and contrast material washout were the most discriminating features selected by CAD for all iterations. CAD selected time-based time-intensity curve (TIC) features 99.0% (207 of 209) of the time to classify FLLs, versus 1.0% (two of 209) of the time for intensity-based features. None of the 15 video-quality criteria had a statistically significant effect on CAD accuracy-all P values were greater than the Holm-Sidak α-level correction for multiple comparisons. Conclusion CAD systems classified benign and malignant FLLs with an accuracy similar to that of an expert reader. CAD improved the accuracy of both readers. Time-based features of TIC were more discriminating than intensity-based features. © RSNA, 2017 Online supplemental material is available for this article.

Combined Analysis of Biparametric MRI and Prostate-Specific Antigen Density: Role in the Prebiopsy Diagnosis of Gleason Score 7 or Greater Prostate Cancer.

OBJECTIVE: The objective of our study was to investigate the diagnostic performance of prebiopsy biparametric MRI (bpMRI) and prostate-specific antigen density (PSAD) for Gleason score (GS) 7 or greater prostate cancer (PCa). MATERIALS AND METHODS: Sixty-eight consecutive patients who underwent prebiopsy bpMRI and biopsy were included. Pathologic results of systemic and targeted biopsies were the reference standard. Qualitative analyses comprised Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) and modified PI-RADSv2 (mPI-RADSv2). Quantitative analyses comprised mean apparent diffusion coefficient (ADC) of tumor, 10th percentile ADC of tumor, mean ADC ratio (ADCR) between benign tissues and PCa, and 10th percentile ADCR between benign tissues and PCa. The AUCs of the following combined models for GS 7 or greater PCa were investigated: model 1, PSAD and PI-RADSv2; model 2, PSAD and mPI-RADSv2; model 3, PSAD and mean ADC; model 4, PSAD and 10th percentile ADC; model 5, PSAD and mean ADCR; and model 6, PSAD and 10th percentile ADCR. RESULTS: The rate of GS 7 or greater PCa was 45.6% (31/68). AUCs of bpMRI parameters were 0.816 for PI-RADSv2, 0.838 for mPI-RADSv2, 0.820 for mean ADC, 0.823 for 10th percentile ADC, 0.780 for mean ADCR, and 0.763 for 10th percentile ADCR (p > 0.05 in all comparisons), whereas AUCs of prostate-specific antigen (PSA)-based parameters were 0.650 for PSA and 0.745 for PSAD (PSA vs PSAD, p = 0.017). AUCs of the combined models from 1 to 6 were 0.860, 0.880, 0.837, 0.844, 0.811, and 0.806, respectively, for biopsy GS 7 or greater PCa (p > 0.05 in all comparisons). CONCLUSION: Combined analysis of prebiopsy bpMRI and PSAD is useful for identifying GS 7 or greater PCa.

Solid Small Renal Mass Without Gross Fat: CT Criteria for Achieving Excellent Positive Predictive Value for Renal Cell Carcinoma.

OBJECTIVE: The purpose of this study was to evaluate CT criteria for achieving high positive predictive value (PPV) for renal cell carcinoma (RCC) in patients with solid small renal masses (SRMs) less than 4 cm without macroscopic fat. MATERIALS AND METHODS: One hundred fifty consecutive patients with a solid SRM without macroscopic fat (mean size ± SD, 2.5 ± 0.8 cm) who underwent CT including unenhanced, corticomedullary (CMP), and nephrographic phases (NP) were evaluated. Pathologically proven solid SRMs without macroscopic fat were classified into RCC (n = 131) and not RCC (n = 19). A "persistent low" sign was defined as a focal area or areas of low attenuation seen at the same location within the lesion on both CMP and NP imaging. Calcification, shape, and lesion attenuation on unenhanced CT were analyzed by two independent readers. RESULTS: PPV of CT criteria (calcification [criterion 1] or spherical shape, lower or equal attenuation, and persistent low sign [criterion 2]) for RCC was 98.3% (58/59) for reader 1 and 100% (53/53) for reader 2. Weighted kappa of interreader agreement was 1.000 for calcification, 0.966 of lower or equal attenuation, 0.834 for spherical shape, 0.823 for persistent low sign, and 0.829 for CT criteria. CONCLUSION: Interpretation of CT allowed reproducible and excellent PPV for RCC. Current CT criteria may effectively shorten the management process for solid SRMs without macroscopic fat by reducing unnecessary biopsy for a substantial number of RCCs showing typical CT findings.

Diffusion-weighted imaging predicts upgrading of Gleason score in biopsy-proven low grade prostate cancers.

OBJECTIVE: To analyse whether diffusion-weighted imaging (DWI) predicts Gleason score (GS) upgrading in biopsy-proven low grade prostate cancer (PCa). PATIENTS AND METHODS: A total of 132 patients who had biopsy-proven low grade (GS < 7) PCa, 3T DWI results, and surgical confirmation were retrospectively included in the study. Clinical variables (prostate-specific antigen, greatest percentage of cancer in a biopsy core and percentage of positive cores) and DWI variables (minimum apparent diffusion coefficient [ADCmin ] and mean ADC [ADCmean ]) were evaluated. ADCmin was measured, by two independent, blinded readers, using a region of interest (ROI) of 5-10 mm2 at the area of lowest ADC value within a cancer, while ADCmean was measured using an ROI covering more than half of a cancer. Logistic regression and receiver-operating characteristic curve analyses were performed. RESULTS: The rate of GS upgrading was 46.1% (61/132). In both univariate and multivariate analyses, ADCmin and ADCmean were persistently significant for predicting GS upgrading (P < 0.05), whereas clinical variables were not (P > 0.05). In both readers' results, the area under the curve (AUC) of ADCmin was significantly greater than that of ADCmean (reader 1: AUC 0.760 vs 0.711; P < 0.001; reader 2: AUC 0.752 vs 0.714; P = 0.003). CONCLUSION: Our results showed that DWI may predict GS upgrading of biopsy-proven low grade PCa. The variable ADCmin in PCa may perform better than ADCmean .

Non-contrast magnetic resonance imaging for bladder cancer: fused high b value diffusion-weighted imaging and T2-weighted imaging helps evaluate depth of invasion.

OBJECTS: To investigate the utility of fused high b value diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) for evaluating depth of invasion in bladder cancer. METHODS: We included 62 patients with magnetic resonance imaging (MRI) and surgically confirmed urothelial carcinoma in the urinary bladder. An experienced genitourinary radiologist analysed the depth of invasion (T stage <2 or ≥2) using T2WI, DWI, T2WI plus DWI, and fused DWI and T2WI (fusion MRI). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were investigated. Area under the curve (AUC) was analysed to identify T stage ≥2. RESULTS: The rate of patients with surgically confirmed T stage ≥2 was 41.9% (26/62). Sensitivity, specificity, PPV, NPV and accuracy were 50.0%, 55.6%, 44.8%, 60.6% and 53.2%, respectively, with T2WI; 57.7%, 77.8%, 65.2%, 71.8% and 69.4%, respectively, with DWI; 65.4%, 80.6%, 70.8%, 76.3% and 74.2%, respectively, with T2WI plus DWI and 80.8%, 77.8%, 72.4%, 84.9% and 79.0%, respectively, with fusion MRI. AUC was 0.528 with T2WI, 0.677 with DWI, 0.730 with T2WI plus DWI and 0.793 with fusion MRI for T stage ≥2. CONCLUSION: Fused high b value DWI and T2WI may be a promising non-contrast MRI technique for assessing depth of invasion in bladder cancer. KEY POINTS: • Accuracy of fusion MRI was 79.0% for T stage ≥2 in bladder cancer. • AUC of fusion MRI was 0.793 for T stage ≥2 in bladder cancer. • Diagnostic performance of fusion MRI was comparable with T2WI plus DWI. • As a non-contrast MRI technique, fusion MRI is useful for bladder cancer.

PI-RADS version 2: quantitative analysis aids reliable interpretation of diffusion-weighted imaging for prostate cancer.

OBJECTIVES: To determine whether apparent diffusion coefficient (ADC) ratio aids reliable interpretation of diffusion-weighted imaging (DWI) for prostate cancer (PCa). METHODS: Seventy-six consecutive patients with PCa who underwent DWI and surgery were included. Based on pathologic tumour location, two readers independently performed DWI scoring according to the revised Prostate Imaging Reporting and Data System (PI-RADSv2). ADC ratios of benign to cancerous prostatic tissue were then measured independently and compared between cases showing concordant and discordant DWI scores ≥4. Area under the curve (AUC) and threshold of ADC ratio were analyzed for DWI scores ≥4. RESULTS: The rate of inter-reader disagreement for DWI score ≥4 was 11.8% (9/76). ADC ratios were higher in concordant vs. discordant DWI scores ≥4 (median, 1.7 vs. 1.1-1.2; p < 0.001). For DWI scores ≥4, the AUCs of ADC ratios were 0.970 for reader 1 and 0.959 for reader 2. In patients with an ADC ratio >1.3, the rate of inter-reader disagreement for DWI score ≥4 decreased to 5.9-6.0%. An ADC ratio >1.3 yielded 100% (reader 1, 54/54; reader 2, 51/51) positive predictive value for clinically significant cancer. CONCLUSION: ADC ratios may be useful for reliable interpretation of DWI score ≥4 in PI-RADSv2. KEY POINTS: • The ADC ratio correlated positively with DWI score of PI-RADSv2. • ADC ratio >1.3 was associated with concordant interpretation of DWI score ≥4. • ADC ratio >1.3 was associated with high PPV for clinically significant cancer. • ADC ratio is useful for reliable interpretation of DWI scoring in PI-RADSv2.

Usefulness of Multiparametric Ultrasound for Evaluating Structural Abnormality of Transplanted Kidney: Can We Predict Histologic Abnormality on Renal Biopsy in Advance?

OBJECTIVE: The purpose of this study was to investigate the associations between microscopic abnormalities of transplanted kidneys and sonography-based imaging biomarkers, including elasticity, venous impedance index, arterial resistive index, and size. MATERIALS AND METHODS: Between 2011 and 2015, 159 recipients underwent sonography and biopsy of a transplanted kidney at our institution; 104 adult patients were included in this study. The maximal longitudinal length on gray-scale images, arterial resistive index, and venous impedance index on Doppler images and shear wave velocity on acoustic radiation force impulse imaging or Young modulus on supersonic shear imaging were measured before biopsy. The Banff criteria (2009 update), an international standardized classification and scoring system for renal allograft pathology, were used to evaluate the biopsy samples. Sonography parameters and clinical variables were analyzed with individual and summed Banff scores. RESULTS: Spearman rank correlation coefficients and ordinal logistic regression showed no association between sonography parameters and summed Banff scores. Only the interval between transplant and biopsy was significantly associated with summed Banff scores (p < 0.05). Univariate logistic regression analysis with individual Banff scores showed associations of one Banff feature with arterial resistive index, three with venous impedance index, and six with interval between transplant and biopsy (p < 0.05). Sonoelastography parameters were not associated with any individual Banff score. CONCLUSION: Neither sonoelastography parameter was associated with any histopathologic change of renal allografts. Although arterial resistive index and venous impedance index were related to a few individual Banff scores, length of time between transplant and biopsy showed stronger correlation than any imaging biomarkers with renal allograft deterioration.

Prostate Cancer: PI-RADS Version 2 Helps Preoperatively Predict Clinically Significant Cancers.

Purpose To retrospectively analyze whether Prostate Imaging Reporting and Data System (PI-RADS) version 2 is helpful for the detection of clinically significant prostate cancer. Materials and Methods Institutional review board approved this retrospective study. A total of 425 patients with prostate cancer who had undergone magnetic resonance (MR) imaging and radical prostatectomy were included. Preoperative parameters such as prostate-specific antigen, biopsy Gleason score, greatest percentage of the core, percentage of the positive core number, and score at PI-RADS version 2 with MR imaging were investigated. Two independent readers performed PI-RADS scoring. Clinically significant prostate cancer was defined as follows: (a) Gleason score of 7 or greater, (b) tumor volume of 0.5 cm(3) or greater, or a (c) positive extracapsular extension or seminal vesicle invasion. The reference standard was based on review of surgical specimen. Logistic regression was conducted to determine which parameters are associated with the presence of clinically significant cancer. Interreader agreement (ie, score ≥4 or not) was investigated by using κ statistics. Results At univariate analysis, all of the preoperative parameters were significant for clinically significant prostate cancer (P < .05). However, multivariate analysis revealed that PI-RADS score was the only significant parameter for both readers (reader 1: odds ratio = 28.170, P = .002; reader 2: odds ratio = 5.474, P = .007). The interreader agreement was excellent for PI-RADS score of 4 or greater (weighted κ = 0.801; 95% confidence interval: 0.737, 0.865). Conclusion The use of PI-RADS version 2 may help preoperatively diagnose clinically significant prostate cancer. (©) RSNA, 2016.

Prediction of biochemical recurrence after radical prostatectomy with PI-RADS version 2 in prostate cancers: initial results.

OBJECTIVES: To determine whether the Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) helps predict biochemical recurrence (BCR) after radical prostatectomy for prostate cancer (PCa). METHODS: We included 158 patients with PCa who underwent magnetic resonance imaging (MRI) and radical prostatectomy (RP). Clinical (prostate-specific antigen, greatest percentage of core, and percentage of positive core number), PI-RADSv2 score on MRI, and surgical parameters (Gleason score, extracapsular extension, seminal vesicle invasion, and tumour volume) were investigated. Univariate and multivariate analyses using Cox's proportional hazards model were performed to assess parameters predictive of BCR (two consecutive prostate specific antigens ≥0.2 ng/ml). Kaplan-Meier survival curves were analyzed. RESULTS: The rate of BCR was 13.3 % (21/158) after surgery (median follow-up, 25 months; range, 12-36). No subject with a PI-RADS score <4 had BCR. In univariate analysis, all parameters were significant for BCR (p < 0.05), except seminal vesicle invasion (p = 0.254). Meanwhile, PI-RADS score was the only independent parameter for BCR in multivariate analysis (p < 0.05). Two-year, BCR-free survival post-RP was significantly lower for PI-RADS ≥4 (84.7-85.5 %) than for PI-RADS <4 (100 %; p < 0.05). CONCLUSION: As a preoperative imaging tool, PI-RADSv2 may be useful to predict BCR after radical prostatectomy for PCa. KEY POINTS: • No subject with PI-RADS <4 had BCR after RP • PI-RADSv2 was the only predictor of BCR in multivariate analysis • Two-year, BCR-free survival following RP was lower for PI-RADS≥4 than for PI-RADS<4 • Inter-rater agreement was good for PI-RADS ≥4 or not.

Differentiation between borderline and benign ovarian tumors: combined analysis of MRI with tumor markers for large cystic masses (≥5 cm).

BACKGROUND: There is overlap in imaging features between borderline and benign ovarian tumors. PURPOSE: To analyze diagnostic performance of magnetic resonance imaging (MRI) combined with tumor markers for differentiating borderline from benign ovarian tumor. MATERIAL AND METHODS: Ninety-nine patient with MRI and surgically confirmed ovarian tumors 5 cm or larger (borderline, n = 37; benign, n = 62) were included. On MRI, tumor size, septal number (0; 1-4; 5 or more), and presence of solid portion such as papillary projection or septal thickening 0.5 cm or larger were investigated. Serum tumor markers (carbohydrate antigen 125 [CA 125] and CA 19-9) were recorded. Multivariate analysis was conducted for assessing whether combined MRI with tumor markers could differentiate borderline from benign tumor. The diagnostic performance was also analyzed. RESULTS: Incidence of solid portion was 67.6% (25/37) in borderline and 3.2% (2/62) in benign tumors (P < 0.05). In all patients, without combined analysis of MRI with tumor markers, multivariate analysis revealed solid portion (P < 0.001) and CA 125 (P = 0.039) were significant for predicting borderline tumors. When combined analysis of MRI with CA 125 ((i) the presence of solid portion or (ii) CA 125 > 44.1 U/mL with septal number ≥5 for borderline tumor) is incorporated to multivariate analysis, it was only significant (P = 0.001). The sensitivity, specificity, PPV, NPV, and accuracy of combined analysis of MRI with CA 125 were 89.1%, 91.9%, 86.8%, 93.4, and 90.9%, respectively. CONCLUSION: Combined analysis of MRI with CA 125 may allow better differentiation between borderline and benign ovarian tumor compared with MRI alone.

Prediction of Micrometastasis (< 1 cm) to Pelvic Lymph Nodes in Prostate Cancer: Role of Preoperative MRI.

OBJECTIVE: The purpose of this study was to retrospectively investigate whether preoperative MRI plays a key role in clinical prediction of micrometastasis (< 1 cm) to pelvic lymph nodes in prostate cancer. MATERIALS AND METHODS: One hundred one patients with prostate cancer who underwent preoperative MRI and radical prostatectomy with pelvic lymph node dissection were included. None of the patients had a pelvic lymph node with a short-axis diameter of 1 cm or larger on MRI. Both clinical (prostate-specific antigen, biopsy Gleason score, greatest percentage of biopsy core, and percentage of positive cores) and MRI parameters (tumor apparent diffusion coefficient and tumor staging) were assessed. The univariate, multivariate, and ROC curve analyses were conducted. RESULTS: Of 101 patients, nine (8.9%) had pelvic lymph node metastases. In univariate analysis, all of the clinical and MRI parameters were related to micrometastasis to pelvic lymph nodes (p < 0.05). However, multivariate analysis revealed that only preoperative MRI stage was significant (p = 0.044). AUC of preoperative MRI stage was 0.954 (odds ratio, 21.7). Respective sensitivity and specificity of preoperative tumor staging by MRI were 100% and 65.2% with cutoff of T3a or more, and 88.9% and 94.6% with cutoff of T3b for predicting micrometastasis to pelvic lymph nodes. CONCLUSION: Preoperative MRI staging may play a role in prediction of micrometastasis (< 1 cm) to pelvic lymph nodes in prostate cancer.

Prediction of Adrenal Adenomas With Hypercortisolism by Using Adrenal Computed Tomography: Emphasis on Contralateral Adrenal Thinning.

PURPOSE: To analyze computed tomography (CT) characteristics of adrenal adenomas with hypercortisolism on adrenal CT compared to adenomas with hyperaldosteronism. MATERIALS AND METHODS: Thirty-two adrenal adenomas, consisting of group A (hypercortisolism, n = 16) and group B (hyperaldosteronism, n = 16), were evaluated with adrenal CT. Thirty-four patients without adrenal nodule on CT and hormonal abnormality (group C) were selected for comparison. In adenomas, lesion size, attenuation value, and absolute and relative washout were compared between groups A and B. The mean adrenal thickness was compared quantitatively and qualitatively between groups. RESULTS: All of adenomas satisfied absolute (≥60%) or relative (≥40%) washout criteria of adrenal CT. The mean adrenal thickness was 1.6 ± 0.3 mm in group A, 2.9 ± 0.5 mm in group B, and 3.0 ± 0.4 mm in group C (group A versus B or C, P < 0.001; group B versus C, P = 0.775). For differentiating group A from B, the area under the curve of quantitative and qualitative analyses for contralateral adrenal thickness was 0.982 and 0.934, respectively. Both sensitivity and specificity with cutoff of 2.0 mm or less in thickness and probably thin or more in visual score were 93.7% and 93.7%, and 87.5% and 93.7%, respectively, for predicting group A. CONCLUSIONS: Contralateral adrenal thinning on CT helps predict adrenal adenomas with hypercortisolism.

Peripheral zone thickness in preoperative MRI is predictive of Trifecta achievement after Holmium laser enucleation of the prostate (HoLEP).

PURPOSE: To investigate various anatomical features of the prostate using preoperative MRI and patients' clinical factors to identify predictors of successful Holmium:YAG laser enucleation of the prostate (HoLEP). METHODS: 71 patients who had received HoLEP and undergone a 3.0-T prostate MRI scan within 6 months before surgery were retrospectively enrolled. MRI features (e.g., total prostate and transitional zone volume, peripheral zone thickness [PZT], BPH patterns, prostatic urethral angle, intravesical prostatic protrusion, etc.) and clinical data (e.g., age, body mass index, surgical technique, etc.) were analyzed using univariable and multivariable logistic regression to identify predictors of successful HoLEP. Successful HoLEP was defined as achieving the Trifecta, characterized by the contemporary absence of postoperative complications within 3 months, a 3-month postoperative maximum flow rate (Qmax) > 15 mL/s, and no urinary incontinence at 3 months postoperatively. RESULTS: Trifecta achievement at 3 months post-surgery was observed in 37 (52%) patients. Patients with Trifecta achievement exhibited a lower preoperative IPSS-quality of life score (QoL) (4.1 vs. 4.5, P = 0.016) and a thinner preoperative peripheral zone thickness (PZT) on MRI (7.9 vs.10.3 mm, P < 0.001). In the multivariable regression analysis, a preoperative IPSS-QoL score < 5 (OR 3.98; 95% CI, 1.21-13.07; P = 0.017) and PZT < 9 mm (OR 11.51; 95% CI, 3.51-37.74; P < 0.001) were significant predictors of Trifecta achievement after HoLEP. CONCLUSIONS: Alongside the preoperative QoL score, PZT measurement in prostate MRI can serve as an objective predictor of successful HoLEP. Our results underscore an additional utility of prostate MRI beyond its role in excluding concurrent prostate cancer.

Discrepancy between preoperative imaging and surgical findings in patients with advanced ovarian cancer: a study of initial false-negative lesions.

OBJECTIVE: The objective of this study was to determine the patterns of erroneous interpretation of preoperative computed tomography (CT) for detection of peritoneal lesions in advanced ovarian cancer. METHODS: Between 2007 and 2011, 148 patients with International Federation of Gynecology and Obstetrics stage IIIC-IV ovarian cancer, who underwent multi-detector-row CT before primary cytoreduction, were enrolled. We reviewed the preoperative CT and compared the findings with the surgical findings. For the discrepant cases, false-negative cases were reevaluated after revealing of surgical findings and were categorized as either absence or presence of lesion (missed case). We performed region-based comparisons according to predefined peritoneal lesion locations. RESULTS: Sixty-eight false-negative cases were identified, of which 43 were revealed to be initially missed cases. The most common locations were found to be the small-bowel mesentery (21%), subdiaphragmatic space (19%), and porta hepatis (16%). CONCLUSIONS: The missed peritoneal implants commonly resided in the same sites of preoperative imaging criteria that could predict suboptimal primary cytoreduction.

Use of Imaging and Biopsy in Prostate Cancer Diagnosis: A Survey From the Asian Prostate Imaging Working Group.

OBJECTIVE: To elucidate the use of radiological studies, including nuclear medicine, and biopsy for the diagnosis and staging of prostate cancer (PCA) in clinical practice and understand the current status of PCA in Asian countries via an international survey. MATERIALS AND METHODS: The Asian Prostate Imaging Working Group designed a survey questionnaire with four domains focused on prostate magnetic resonance imaging (MRI), other prostate imaging, prostate biopsy, and PCA backgrounds. The questionnaire was sent to 111 members of professional affiliations in Korea, Japan, Singapore, and Taiwan who were representatives of their working hospitals, and their responses were analyzed. RESULTS: This survey had a response rate of 97.3% (108/111). The rates of using 3T scanners, antispasmodic agents, laxative drugs, and prostate imaging-reporting and data system reporting for prostate MRI were 21.6%-78.9%, 22.2%-84.2%, 2.3%-26.3%, and 59.5%-100%, respectively. Respondents reported using the highest b-values of 800-2000 sec/mm² and fields of view of 9-30 cm. The prostate MRI examinations per month ranged from 1 to 600, and they were most commonly indicated for biopsy-naïve patients suspected of PCA in Japan and Singapore and staging of proven PCA in Korea and Taiwan. The most commonly used radiotracers for prostate positron emission tomography are prostate-specific membrane antigen in Singapore and fluorodeoxyglucose in three other countries. The most common timing for prostate MRI was before biopsy (29.9%). Prostate-targeted biopsies were performed in 63.8% of hospitals, usually by MRI-ultrasound fusion approach. The most common presentation was localized PCA in all four countries, and it was usually treated with radical prostatectomy. CONCLUSION: This survey showed the diverse technical details and the availability of imaging and biopsy in the evaluation of PCA. This suggests the need for an educational program for Asian radiologists to promote standardized evidence-based imaging approaches for the diagnosis and staging of PCA.

Prediction of early response to uterine arterial embolisation of adenomyosis: value of T2 signal intensity ratio of adenomyosis.

OBJECTIVES: To identify imaging predictors for complete necrosis after uterine artery embolisation (UAE) via quantitative measurement of the signal intensity obtained from magnetic resonance imaging (MRI) of a patient with adenomyosis. METHODS: The MRIs of 119 patients with uterine adenomyosis, who underwent UAE, were retrospectively evaluated. Each lesion was classified based on its location and morphology on MRI. Thickness and signal intensity were measured in each adenomyosis and in the rectus muscle on the T2-weighted sagittal plane, and the T2-weighted signal intensity ratio (T2SR) was calculated. MR parameters were then compared in patients showing complete response that achieved complete necrosis and incomplete response after UAE via univariate and multivariate analysis. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance of the predictor using MR parameters for differentiating the complete from the incomplete response. RESULTS: The complete necrosis rate was 66.4 % (79/119) after UAE for adenomyosis. Univariate and multivariate analysis results indicated that T2SR was associated significantly with complete necrosis (P = 0.012). Symptomatic adenomyosis with T2SR above 0.475 was associated with complete necrosis after UAE (sensitivity = 57.0, specificity = 70.0, area under the ROC curve [AUC] = 0.643). CONCLUSION: T2SR of adenomyosis on pre-procedural MRI can be utilised as a predictor for early therapeutic response of UAE in adenomyosis.

Usefulness of the virtual monochromatic image in dual-energy spectral CT for decreasing renal cyst pseudoenhancement: a phantom study.

OBJECTIVE: The purpose of this study was to determine the effect that dual-energy spectral CT has on renal cyst pseudoenhancement with a renal cyst phantom. MATERIALS AND METHODS: Two renal compartments within a CT phantom were filled with 40- and 240-HU solutions of diluted contrast material, mimicking the nonenhanced phase and nephrographic phase of MDCT, respectively. A saline-filled tapering cylindric cyst model was used, simulating cysts of varying diameters (range, 0.7-3.0 cm) suspended in the renal compartments. The phantom was scanned using dual-energy CT (DECT) (80 and 140 kVp) and conventional, single-energy CT (120 kVp) with the same 64-MDCT scanner. Attenuation increase was measured for a cyst model within 40- and 240-HU dilutions. We compared the attenuation increase obtained on virtual monochromatic images from DECT with conventional, single-energy MDCT images using a paired Student t test. RESULTS: Pseudoenhancement occurred in the conventional single-energy CT acquisitions, with water attenuation increase of 42.44 ± 4.03 HU measured at 120 kVp. In virtual monochromatic images of DECT, we observed less pseudoenhancement with water attenuation increase of 21.51 ± 6.18 HU at 70 keV. Both acquisitions yielded a p value less than 0.0001. CONCLUSION: We achieved less pseudoenhancement of renal cysts with virtual monochromatic images of DECT compared with conventional single-energy CT. This method may be useful when an accurate differentiation between small renal cysts and solid masses is critical.

Facile synthesis of multimeric micelles.

Bringing it all together: Synthesis of a dimeric micelle (see scheme) is shown to produce specifically linked Janus-like micelles. The reaction conditions for dimeric micelle formation were optimized and the resulting micelles characterized. Trimeric, tetrameric, and multimeric micelles were also synthesized using the same technique.