Hyperoxia-Induced ΔR1 : MRI Biomarker of Histological Infarction in Acute Cerebral Stroke

Objective@#To evaluate whether hyperoxia-induced ΔR1 (hyperO2ΔR1) can accurately identify histological infarction in an acute cerebral stroke model. @*Materials and Methods@#In 18 rats, MRI parameters, including hyperO2ΔR1, apparent diffusion coefficient (ADC), cerebral blood flow and volume, and 18F-fluorodeoxyglucose uptake on PET were measured 2.5, 4.5, and 6.5 hours after a 60-minutes occlusion of the right middle cerebral artery. Histological examination of the brain was performed immediately following the imaging studies. MRI and PET images were co-registered with digitized histological images. The ipsilateral hemisphere was divided into histological infarct (histological cell death), non-infarct ischemic (no cell death but ADC decrease), and nonischemic (no cell death or ADC decrease) areas for comparisons of imaging parameters. The levels of hyperO2ΔR1 and ADC were measured voxel-wise from the infarct core to the non-ischemic region. The correlation between areas of hyperO2ΔR1-derived infarction and histological cell death was evaluated. @*Results@#HyperO2ΔR1 increased only in the infarct area (p ≤ 0.046) compared to the other areas. ADC decreased stepwise from non-ischemic to infarct areas (p = 0.002 at all time points). The other parameters did not show consistent differences among the three areas across the three time points. HyperO2ΔR1 sharply declined from the core to the border of the infarct areas, whereas there was no change within the non-infarct areas. A hyperO2ΔR1 value of 0.04 s-1 was considered the criterion to identify histological infarction. ADC increased gradually from the infarct core to the periphery, without a pronounced difference at the border between the infarct and non-infarct areas. Areas of hyperO2ΔR1 higher than 0.04 s-1 on MRI were strongly positively correlated with histological cell death (r = 0.862; p < 0.001). @*Conclusion@#HyperO2ΔR1 may be used as an accurate and early (2.5 hours after onset) indicator of histological infarction in acute stroke.

Construction of a Retrospective Cohort to Observe 10-Year Urologic Cancer Treatment Trends at the Biggest Medical Center of South Korea

Purpose@#To construct a urologic cancer database using a standardized, reproducible method, and to assess preliminary characteristics of this cohort. @*Materials and Methods@#Patients with prostate, bladder, and kidney cancers who were enrolled with diagnostic codes in the electronic medical record (EMR) at Asan Medical Center from 2007–2016 were included. Research Electronic Data Capture (REDCap) was used to design the Asan Medical Center-Urologic Cancer Database (AMC-UCD). The process included developing a data dictionary, applying branching logic, mapping clinical data warehouse structures, alpha testing, clinical record summary testing, creating “standards of procedure,” importing data, and entering data. Descriptive statistics were used to identify rates of surgeries and numbers of patients. @*Results@#Clinical variables (n=407) were selected to develop a data dictionary from REDCap. In total, 20,198 urologic cancer patients visited our institution from 2007–2016 (bladder cancer, 4,616; kidney cancer, 5,750; prostate cancer, 10,330). The overall numbers of patients and surgeries increased over time, with robotic surgeries rapidly growing over a decade. The most common treatment for urologic cancer was surgery, followed by chemotherapy and radiation therapy. @*Conclusions@#Using a standardized method, the AMC-UCD fosters multidisciplinary research. This constructed database provides access to clinical statistics to effectively assist research. Preliminary data should be refined through EMR chart review. The successful organization of data from 2007–2016 provides a framework for future periods of investigation and prospective models.

Preoperative Assessment of Renal Sinus Invasion by Renal Cell Carcinoma according to Tumor Complexity and Imaging Features in Patients Undergoing Radical Nephrectomy

Objective@#To identify the association between renal tumor complexity and pathologic renal sinus invasion (RSI) and evaluate the usefulness of computed tomography tumor features for predicting RSI in patients with renal cell carcinoma (RCC). @*Materials and Methods@#This retrospective study included 276 consecutive patients who underwent radical nephrectomy for RCC with a size of ≤ 7 cm between January 2014 and October 2017. Tumor complexity and anatomical renal sinus involvement were evaluated using two standardized scoring systems: the radius (R), exophytic or endophytic (E), nearness to collecting system or sinus (N), anterior or posterior (A), and location relative to polar lines (RENAL) nephrometry and preoperative aspects and dimensions used for anatomical classification (PADUA) system. CT-based tumor features, including shape, enhancement pattern, margin at the interface of the renal sinus (smooth vs. non-smooth), and finger-like projection of the mass, were also assessed by two independent radiologists. Univariable and multivariable logistic regression analyses were performed to identify significant predictors of RSI. The positive predictive value, negative predictive value (NPV), accuracy of anatomical renal sinus involvement, and tumor features were evaluated. @*Results@#Eighty-one of 276 patients (29.3%) demonstrated RSI. Among highly complex tumors (RENAL or PADUA score ≥ 10), the frequencies of RSI were 42.4% (39/92) and 38.0% (71/187) using RENAL and PADUA scores, respectively. Multivariable analysis showed that a non-smooth margin and the presence of a finger-like projection were significant predictors of RSI.Anatomical renal sinus involvement showed high NPVs (91.7% and 95.2%) but low accuracy (40.2% and 43.1%) for RSI, whereas the presence of a non-smooth margin or finger-like projection demonstrated comparably high NPVs (90.0% and 91.3% for both readers) and improved accuracy (67.0% and 73.9%, respectively). @*Conclusion@#A non-smooth margin or the presence of a finger-like projection can be used as a preoperative CT-based tumor feature for predicting RSI in patients with RCC.

Preoperative Assessment of Renal Sinus Invasion by Renal Cell Carcinoma according to Tumor Complexity and Imaging Features in Patients Undergoing Radical Nephrectomy

Objective@#To identify the association between renal tumor complexity and pathologic renal sinus invasion (RSI) and evaluate the usefulness of computed tomography tumor features for predicting RSI in patients with renal cell carcinoma (RCC). @*Materials and Methods@#This retrospective study included 276 consecutive patients who underwent radical nephrectomy for RCC with a size of ≤ 7 cm between January 2014 and October 2017. Tumor complexity and anatomical renal sinus involvement were evaluated using two standardized scoring systems: the radius (R), exophytic or endophytic (E), nearness to collecting system or sinus (N), anterior or posterior (A), and location relative to polar lines (RENAL) nephrometry and preoperative aspects and dimensions used for anatomical classification (PADUA) system. CT-based tumor features, including shape, enhancement pattern, margin at the interface of the renal sinus (smooth vs. non-smooth), and finger-like projection of the mass, were also assessed by two independent radiologists. Univariable and multivariable logistic regression analyses were performed to identify significant predictors of RSI. The positive predictive value, negative predictive value (NPV), accuracy of anatomical renal sinus involvement, and tumor features were evaluated. @*Results@#Eighty-one of 276 patients (29.3%) demonstrated RSI. Among highly complex tumors (RENAL or PADUA score ≥ 10), the frequencies of RSI were 42.4% (39/92) and 38.0% (71/187) using RENAL and PADUA scores, respectively. Multivariable analysis showed that a non-smooth margin and the presence of a finger-like projection were significant predictors of RSI.Anatomical renal sinus involvement showed high NPVs (91.7% and 95.2%) but low accuracy (40.2% and 43.1%) for RSI, whereas the presence of a non-smooth margin or finger-like projection demonstrated comparably high NPVs (90.0% and 91.3% for both readers) and improved accuracy (67.0% and 73.9%, respectively). @*Conclusion@#A non-smooth margin or the presence of a finger-like projection can be used as a preoperative CT-based tumor feature for predicting RSI in patients with RCC.

Imaging-Guided Biopsy, Percutaneous Ablation, and Active Surveillance for Small Renal Masses

The diagnosis rates of small renal masses less than 4 cm in diameter are increasing with the increasing number of CT and MRI examinations. Since these small renal masses include a high proportion of benign tumors and low-malignant renal cell carcinomas, image-guided biopsy plays an important role in facilitating accurate diagnosis, low-invasive percutaneous radiofrequency- or cryo-ablation, and active surveillance for these masses. Therefore, the diagnostic accuracy and safety of image-guided biopsy for small renal masses, but awareness of the technical aspects of image-guided percutaneous ablation and an understanding of active surveillance are crucial in establishing an adequate treatment plan. The purpose of this review is to present the basic knowledge and clinical usefulness of the diagnosis trends for small renal masses, discuss the diagnostic accuracy of imaging-guided biopsy, and assess the use of low-invasive therapy with percutaneous ablation and active surveillance.

Neuroendocrine Tumor of the Renal Pelvis Presenting with Urinary Tract Obstruction: A Case Report

Primary renal neuroendocrine tumor (NET) is an extremely rare disease with fewer than 100 reported cases to date. Among them, only three involved the renal pelvis, to our knowledge. Here, we report another rare case of primary NET in the renal pelvis of a 33-year-old man. Initial computed tomography (CT) scanning of the abdomen and pelvis revealed a necrotic mass with peritumoral infiltration at the left renal pelvis and ureteropelvic junction causing urinary tract obstruction. A follow-up CT scan revealed an intratumoral hemorrhage. The patient then underwent nephrectomy. The results of a subsequent histopathological examination were consistent with a well-differentiated NET. No lymph nodes or paraganglia were found within the tumor, and further imaging revealed no other primary or metastatic lesions. Therefore, the patient was diagnosed with primary NET in the renal pelvis. We discuss this rare case and briefly review the current NET literature.

Diagnostic value of integrated ¹⁸F-fluoro-2-deoxyglucose positron emission tomography/computed tomography in recurrent epithelial ovarian cancer: accuracy of patient selection for secondary cytoreduction in 134 patients / 부인종양

OBJECTIVE: The aim of this study was to evaluate the diagnostic value of integrated 18F-fluoro-2-deoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) for suspected recurrence of epithelial ovarian cancer (EOC) with non-disseminated lesions. METHODS: We retrospectively reviewed the medical records of recurrent EOC patients who underwent secondary cytoreduction from January 2000 to December 2013. A total of 134 patients underwent secondary cytoreduction after imaging with either 18F-FDG-PET/CT or contrast-enhanced computed tomography (CECT). RESULTS: In a patient-based analysis of 134 patients, 124 (92.5%) were confirmed to be positive for malignancy. Among 72 patients with suspected non-disseminated recurrence on 18F-FDG-PET/CT, 65 (89.0%) were confirmed to have recurrence, giving 98.5% sensitivity, 87.7% accuracy, and 88.9% positive predictive value (PPV). In the 65 patients with recurrence, residual tumor remained in 14 patients, giving an accuracy of patient selection for secondary cytoreduction of 69.4% (50/72) and it is higher than that of CECT (64.0%). In 169 lesions removed from patients who underwent preoperative 18F-FDG-PET/CT, 135 (79.9%) were confirmed to be positive for malignancy and 124 were accurately detected by 18F-FDG-PET/CT, giving 91.9% sensitivity, 81.1% accuracy, and 85.5% PPV. Foreign body granuloma was found in 33.3% of 21 lesions with false-positive 18F-FDG-PET/CT findings (7/21). The mean preoperative cancer antigen 125 (CA-125) level in false-positive patients was 28.8 U/mL. CONCLUSION: Compared with CECT, 18F-FDG-PET/CT shows higher sensitivity in lesion-based analysis and better accuracy of patient selection for secondary cytoreduction. However, there is still a need for integration of the results of 18F-FDG-PET/CT, CECT, and CA-125 levels to aid treatment planning.

Influence of B₁-Inhomogeneity on Pharmacokinetic Modeling of Dynamic Contrast-Enhanced MRI: A Simulation Study

OBJECTIVE: To simulate the B₁-inhomogeneity-induced variation of pharmacokinetic parameters on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). MATERIALS AND METHODS: B₁-inhomogeneity-induced flip angle (FA) variation was estimated in a phantom study. Monte Carlo simulation was performed to assess the FA-deviation-induced measurement error of the pre-contrast R₁, contrast-enhancement ratio, Gd-concentration, and two-compartment pharmacokinetic parameters (K(trans), v(e), and v(p)). RESULTS: B₁-inhomogeneity resulted in −23–5% fluctuations (95% confidence interval [CI] of % error) of FA. The 95% CIs of FA-dependent % errors in the gray matter and blood were as follows: −16.7–61.8% and −16.7–61.8% for the pre-contrast R₁, −1.0–0.3% and −5.2–1.3% for the contrast-enhancement ratio, and −14.2–58.1% and −14.1–57.8% for the Gd-concentration, respectively. These resulted in −43.1–48.4% error for K(trans), −32.3–48.6% error for the v(e), and −43.2–48.6% error for v(p). The pre-contrast R₁ was more vulnerable to FA error than the contrast-enhancement ratio, and was therefore a significant cause of the Gd-concentration error. For example, a −10% FA error led to a 23.6% deviation in the pre-contrast R₁, −0.4% in the contrast-enhancement ratio, and 23.6% in the Gd-concentration. In a simulated condition with a 3% FA error in a target lesion and a −10% FA error in a feeding vessel, the % errors of the pharmacokinetic parameters were −23.7% for K(trans), −23.7% for v(e), and −23.7% for v(p). CONCLUSION: Even a small degree of B₁-inhomogeneity can cause a significant error in the measurement of pharmacokinetic parameters on DCE-MRI, while the vulnerability of the pre-contrast R₁ calculations to FA deviations is a significant cause of the miscalculation.

The Effects of Breathing Motion on DCE-MRI Images: Phantom Studies Simulating Respiratory Motion to Compare CAIPIRINHA-VIBE, Radial-VIBE, and Conventional VIBE

OBJECTIVE: To compare the breathing effects on dynamic contrast-enhanced (DCE)-MRI between controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA)-volumetric interpolated breath-hold examination (VIBE), radial VIBE with k-space-weighted image contrast view-sharing (radial-VIBE), and conventional VIBE (c-VIBE) sequences using a dedicated phantom experiment. MATERIALS AND METHODS: We developed a moving platform to simulate breathing motion. We conducted dynamic scanning on a 3T machine (MAGNETOM Skyra, Siemens Healthcare) using CAIPIRINHA-VIBE, radial-VIBE, and c-VIBE for six minutes per sequence. We acquired MRI images of the phantom in both static and moving modes, and we also obtained motion-corrected images for the motion mode. We compared the signal stability and signal-to-noise ratio (SNR) of each sequence according to motion state and used the coefficients of variation (CoV) to determine the degree of signal stability. RESULTS: With motion, CAIPIRINHA-VIBE showed the best image quality, and the motion correction aligned the images very well. The CoV (%) of CAIPIRINHA-VIBE in the moving mode (18.65) decreased significantly after the motion correction (2.56) (p < 0.001). In contrast, c-VIBE showed severe breathing motion artifacts that did not improve after motion correction. For radial-VIBE, the position of the phantom in the images did not change during motion, but streak artifacts significantly degraded image quality, also after motion correction. In addition, SNR increased in both CAIPIRINHA-VIBE (from 3.37 to 9.41, p < 0.001) and radial-VIBE (from 4.3 to 4.96, p < 0.001) after motion correction. CONCLUSION: CAIPIRINHA-VIBE performed best for free-breathing DCE-MRI after motion correction, with excellent image quality.

The characteristics and spatial distributions of initially missed and rebiopsy-detected prostate cancers

PURPOSE: The purpose of this study was to analyze the characteristics of initially missed and rebiopsy-detected prostate cancers following 12-core transrectal biopsy. METHODS: A total of 45 patients with prostate cancers detected on rebiopsy and 45 patients with prostate cancers initially detected on transrectal ultrasound-guided biopsy were included in the study. For result analysis, the prostate was divided into six compartments, and the cancer positive rates, estimated tumor burden, and agreement rates between biopsy and surgical specimens, along with clinical data, were evaluated. RESULTS: The largest mean tumor burden was located in the medial apex in both groups. There were significantly more tumors in this location in the rebiopsy group (44.9%) than in the control group (30.1%, P=0.015). The overall sensitivity of biopsy was significantly lower in the rebiopsy group (22.5% vs. 43.4%, P<0.001). The agreement rate of cancer positive cores between biopsy and surgical specimens was significantly lower in the medial apex in the rebiopsy group compared with that of the control group (50.0% vs. 65.6%, P=0.035). The cancer positive rates of target biopsy cores and premalignant lesions in the rebiopsy group were 63.1% and 42.3%, respectively. CONCLUSION: Rebiopsy-detected prostate cancers showed different spatial distribution and lower cancer detection rate of biopsy cores compared with initially diagnosed cancers. To overcome lower cancer detection rate, target biopsy of abnormal sonographic findings, premalignant lesions and medial apex which revealed larger tumor burden would be recommended when performing rebiopsy.

Multiparametric magnetic resonance imaging for prostate cancer: A review and update for urologists

Recently, imaging of prostate cancer has greatly advanced since the introduction of multiparametric magnetic resonance imaging (mpMRI). mpMRI consists of T2-weighted sequences combined with several functional sequences including diffusion-weighted imaging, dynamic contrast-enhanced imaging, and/or magnetic resonance spectroscopy imaging. Interest has been growing in mpMRI because no single MRI sequence adequately detects and characterizes prostate cancer. During the last decade, the role of mpMRI has been expanded in prostate cancer detection, staging, and targeting or guiding prostate biopsy. Recently, mpMRI has been used to assess prostate cancer aggressiveness and to identify anteriorly located tumors before and during active surveillance. Moreover, recent studies have reported that mpMRI is a reliable imaging modality for detecting local recurrence after radical prostatectomy or external beam radiation therapy. In this regard, some urologic clinical practice guidelines recommended the use of mpMRI in the diagnosis and management of prostate cancer. Because mpMRI is the evolving reference standard imaging modality for prostate cancer, urologists should acquire cutting-edge knowledge about mpMRI. In this article, we review the literature on the use of mpMRI in urologic practice and provide a brief description of techniques. More specifically, we state the role of mpMRI in prostate biopsy, active surveillance, high-risk prostate cancer, and detection of recurrence after radical prostatectomy.

Effects of MR Parameter Changes on the Quantification of Diffusion Anisotropy and Apparent Diffusion Coefficient in Diffusion Tensor Imaging: Evaluation Using a Diffusional Anisotropic Phantom

OBJECTIVE: To validate the usefulness of a diffusional anisotropic capillary array phantom and to investigate the effects of diffusion tensor imaging (DTI) parameter changes on diffusion fractional anisotropy (FA) and apparent diffusion coefficient (ADC) using the phantom. MATERIALS AND METHODS: Diffusion tensor imaging of a capillary array phantom was performed with imaging parameter changes, including voxel size, number of sensitivity encoding (SENSE) factor, echo time (TE), number of signal acquisitions, b-value, and number of diffusion gradient directions (NDGD), one-at-a-time in a stepwise-incremental fashion. We repeated the entire series of DTI scans thrice. The coefficients of variation (CoV) were evaluated for FA and ADC, and the correlation between each MR imaging parameter and the corresponding FA and ADC was evaluated using Spearman's correlation analysis. RESULTS: The capillary array phantom CoVs of FA and ADC were 7.1% and 2.4%, respectively. There were significant correlations between FA and SENSE factor, TE, b-value, and NDGD, as well as significant correlations between ADC and SENSE factor, TE, and b-value. CONCLUSION: A capillary array phantom enables repeated measurements of FA and ADC. Both FA and ADC can vary when certain parameters are changed during diffusion experiments. We suggest that the capillary array phantom can be used for quality control in longitudinal or multicenter clinical studies.

Dynamic Contrast-Enhanced MRI for Monitoring Antiangiogenic Treatment: Determination of Accurate and Reliable Perfusion Parameters in a Longitudinal Study of a Mouse Xenograft Model

OBJECTIVE: To determine the reliable perfusion parameters in dynamic contrast-enhanced MRI (DCE-MRI) for the monitoring antiangiogenic treatment in mice. MATERIALS AND METHODS: Mice, with U-118 MG tumor, were treated with either saline (n = 3) or antiangiogenic agent (sunitinib, n = 8). Before (day 0) and after (days 2, 8, 15, 25) treatment, DCE examinations using correlations of perfusion parameters (Kep, Kel, and AH from two compartment model; time to peak, initial slope and % enhancement from time-intensity curve analysis) were evaluated. RESULTS: Tumor growth rate was found to be 129% +/- 28 in control group, -33% +/- 11 in four mice with sunitinib-treatment (tumor regression) and 47% +/- 15 in four with sunitinib-treatment (growth retardation). Kep (r = 0.80) and initial slope (r = 0.84) showed strong positive correlation to the initial tumor volume (p < 0.05). In control mice, tumor regression group and growth retardation group animals, Kep (r : 0.75, 0.78, 0.81, 0.69) and initial slope (r : 0.79, 0.65, 0.67, 0.84) showed significant correlation with tumor volume (p < 0.01). In four mice with tumor re-growth, Kep and initial slope increased 20% or greater at earlier (n = 2) than or same periods (n = 2) to when the tumor started to re-grow with 20% or greater growth rate. CONCLUSION: Kep and initial slope may a reliable parameters for monitoring the response of antiangiogenic treatment.

Multidisciplinary Functional MR Imaging for Prostate Cancer

Various functional magnetic resonance (MR) imaging techniques are used for evaluating prostate cancer including diffusion-weighted imaging, dynamic contrast-enhanced MR imaging, and MR spectroscopy. These techniques provide unique information that is helpful to differentiate prostate cancer from non-cancerous tissue and have been proven to improve the diagnostic performance of MRI not only for cancer detection, but also for staging, post-treatment monitoring, and guiding prostate biopsies. However, each functional MR imaging technique also has inherent challenges. Therefore, in order to make accurate diagnoses, it is important to comprehensively understand their advantages and limitations, histologic background related with image findings, and their clinical relevance for evaluating prostate cancer. This article will review the basic principles and clinical significance of functional MR imaging for evaluating prostate cancer.

Reliability of Transrectal Ultrasonography in the Prostate Volume Measurement

PURPOSE: The purpose of study was to evaluate the reliability of transrectal ultrasonography (TRUS) in the prostate volume measurement. MATERIALS AND METHODS: Forty-one patients underwent two TRUS examinations during two independent sessions to measure the three-dimensional diameters and volume of the prostate. The difference between the two TRUS examinations was evaluated, and the reliability of TRUS was assessed using the intraclass correlation coefficient (ICC), coefficient of variation (CV), and Bland and Altman plot. RESULTS: The patients were divided into two subgroups by two observers those with the mean prostate volume same or greater than 30 ml (group A) and those with the mean prostate volume less than 30 ml (group B). A prostate volume difference greater than 5 ml and 10 ml between the two TRUS examinations was more frequently included in the group A than in the group B (43% and 33%, 5% and 0%, respectively) (p < 0.05). ICC and CV showed poor reliability for measuring the prostate height, length and volume in the group A (ICC for width, height, length and volume < 0.75, CV for volume =12.97%). CONCLUSION: Prostate volume measurement by TRUS may be unreliable in large prostates with unreliable measurement of the height and length being the primary limiting cause.

Variable CT Findings of Epithelial Origin Ovarian Carcinoma According to the Degree of Histologic Differentiation

OBJECTIVE: We wanted to evaluate the CT findings of epithelial origin ovarian carcinoma according to the degree of histologic differentiation. MATERIALS AND METHODS: This study enrolled 124 patients with 31 well differentiated, 44 moderately differentiated and 95 poorly differentiated carcinomas with epithelial origin. The CT images were retrospectively evaluated with regard to bilateral ovarian involvement, the tumor's nature, lymphadenopathy, adjacent organ invasion, peritoneal tumor seeding, a large amount of ascites and distant metastasis. In cystic, predominantly cystic and mixed tumors, the tumor wall, septa, papillary projection and necrosis in the solid portion were assessed. RESULTS: Bilateral ovarian involvement was more common in the poorly (48%) and moderately (42%) differentiated carcinomas than in the well differentiated carcinomas (7%) (p < 0.05). The frequency of a predominantly solid or solid nature was greater in the moderately and poorly differentiated carcinomas than in the well differentiated carcinomas (p < 0.0001). In the 87 tumors with a cystic, predominantly cystic or mixed nature, septa greater than 3 mm, papillary projection and necrosis in the solid portion were more common in the poorly differentiated carcinoma (91%, 91% and 77%, respectively) than in the moderately (64%, 68% and 34%, respectively) and well differentiated carcinomas (63%, 47% and 27%, respectively) (p < 0.05). Lymphadenopathy, organ invasion, tumor seeding and a large amount of ascites were more common in the poorly differentiated carcinomas (38%, 27%, 73% and 69%, respectively) than in the moderately (13%, 10%, 48% and 45%, respectively) and well differentiated carcinomas (3%, 0%, 10% and 17%, respectively) (p < 0.05). CONCLUSION: Epithelial origin ovarian carcinoma shows different CT findings according to the degree of histologic differentiation.

Usefulness of a Pharmacokinetic Model Based on Dynamic Contrast-enhanced MRI for the Detection and Localization of Prostate Cancer

PURPOSE: To investigate the usefulness of a pharmacokinetic model based on dynamic contrast-enhanced (DCE) MR imaging for the detection and localization of prostate cancer. MATERIALS AND METHODS: Forty-four patients that had undergone radical prostatectomy for prostate cancer and dynamic contrast enhanced (DCE) MR imaging (slice thickness, 4 mm; time resolution of each set, 5 seconds), were enrolled in the study. From the pharmacokinetic model, the time of arrival, and the parameters Ah, Kep, and Kel were extracted and were compared for cancerous tissue and non-cancerous tissue in the central gland and peripheral zone. The diagnostic performance of each parameter for differentiating cancerous tissue from non-cancerous tissue was evaluated using receiver-operating-characteristics analysis. RESULTS: The Kep and Kel values were significantly greater in cancerous tissue (0.13 sec(-1) +/- 0.14 and 1.59 x 10(-3) sec(-1) +/- 1.35 x 10(-3)) than in non-cancerous tissue from the central gland (0.03 sec(-1) +/- 0.02 and 0.26 x 10(-3) sec(-1) +/- 1.24 x 10(-3)) and peripheral zone (0.04 sec(-1) +/- 0.07 and 0.58 x 10(-3) sec(-1) +/- 1.98 x10(-3)) (p < 0.05). The area under the ROC curve for differentiating cancerous from non-cancerous tissue was 0.850 (95% CI, 0.778-0.876) for Kep and 0.814 (95% CI, 0.737-0.876) for Kel. CONCLUSION: Kep and Kel are useful perfusion parameters for the differentiation of prostate cancerous tissue from non-cancerous tissue.

A Prospective Randomized Study Comparing Effectiveness of Local Anesthesia Techniques in Patients undergoing Transrectal Ultrasound-guided Prostate Biopsy / 대한비뇨기과학회지

PURPOSE: This study was designed to compare the effectiveness of intrarectal lidocaine gel versus periprostatic lidocaine injection during TRUS-guided biopsies. MATERIALS AND METHODS: From April 2003 to September 2003, 90 men undergoing a transrectal prostate biopsy were randomized into three groups. In group 1, 30 patients intrarectally received 20ml of 2% lidocaine gel; and group 2, 30 patients received 5ml(2.5ml per side) of 2% lidocaine solution injected along each side of the prostate, near the junction of the seminal vesicle and the base of the prostate(along the neurovascular bundles); in group 3, 30 patients received 5ml(2.5ml per side) of normal saline injected along the neurovascular bundles. The pain level after the biopsy was assessed using a 10-point linear visual analog pain scale(VAS). A statistical analysis was performed using the Wilcoxon Rank Sum test, and the results compared. RESULTS: Patient who received lidocaine solution injections along the neurovascular bundles (Group 2) had significantly lower VAS scores compared to the control group(mean score 3.56+/-2.13 versus 5.83+/-1.94, p<0.0001), but patients who received intrarectal lidocaine gel did not (mean score 5.46+/-2.70 versus 5.83+/-1.94, p=0.671). Gross hematuria, rectal bleeding and hemospermia occurred in 36(40.0%), 6(6.7%) and 5(5.6%) subjects, respectively. One patient had a vasovagal syncope. No patient reported febrile UTI or urinary retention. CONCLUSIONS: Bilateral nerve blockade with local anesthetic is a safe technique that significantly reduces pain during a prostate biopsy. However, in this study, intrarectal lidocaine injection did not reduce the pain compared to the control group during the prostate biopsy.

Bladder Hemangioma Associated with Klippel-Trenaunay Syndrome: Case Report

Klippel-Trenaunay syndrome is a rare congenital vascular disorder characterized by cutaneous hemangioma, multiple varicosities, and hypertrophy of involved extremities. It is rarely associated with bladder hemangioma. The authors report the imaging findings of a case of the Klippel-Trenaunay syndrome involving hemangioma of the bladder.

Unusual Renal Tuberculosis Manifested as an Isolated Renal Mass in an Immunocompromised Patient: A Case Report

Renal tuberculosis commonly involves the urinary tract and results in multifocal fibrosis and stricture. Rarely, it presents as a renal mass with or without urinary tract abnormality. The radiologic features of this rare pseudotumor have not been sufficiently described in the previous literature, and we now report a case of tuberculosis presenting as an isolated renal mass and multiple hepatic nodules without evidence of associated urinary tract abnormality. The condition mimicked malignant neoplastic disease and occurred in a patient who had undergone chemotherapy for leukemia.