Jeong Yeon Cho

Seoul National University Hospital, Sŏul, Seoul, South Korea

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Publications (69)135.83 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Müllerian duct anomalies (MDAs) represent a wide spectrum of developmental abnormalities related to various gynecologic and obstetric complications, including primary amenorrhea, infertility, and endometriosis. The use of diverse imaging modalities, in conjunction with clinical information, provide important clues to the diagnosis of MDAs. Diagnostic imaging work-up for MDAs often begins with hysterosalpingography (HSG) and/or ultrasonography (US). Although HSG and/or US may suffice to detect the presence of a uterine abnormality, magnetic resonance (MR) imaging is generally needed to classify the abnormality into a specific MDA category. MR imaging has been gaining in popularity for use in evaluating MDAs, by virtue of its noninvasiveness, lack of ionizing radiation, and capability for multiplanar imaging and soft tissue characterization. Abnormalities in the external uterine fundal contour are readily recognized with MR imaging, allowing for clear differentiation between a fusion anomaly, such as a uterus didelphys or a bicornuate uterus, and a resorption anomaly, such as a septate uterus. Furthermore, MR imaging enables clear depiction of a rudimentary uterine horn in a unicornuate uterus. Accurate differential diagnosis of MDAs on the basis of their characteristic MR imaging findings is crucial, because the rates of gynecologic and obstetric complications vary considerably among MDAs. The diagnostic accuracy may be enhanced by adopting a systematic approach to MR imaging-based differential diagnosis.
    Abdominal Imaging 07/2014; · 1.91 Impact Factor
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    ABSTRACT: To evaluate the prevalence of known risk factors for contrast-induced nephropathy (CIN) and their association with the actual occurrence of CIN in patients undergoing intravenous contrast-enhanced computed tomography (CECT) in Korea.
    Korean journal of radiology: official journal of the Korean Radiological Society 07/2014; 15(4):456-63. · 1.32 Impact Factor
  • Jeong Yeon Cho, Young Ho Lee
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    ABSTRACT: The incidence of fetal tumors has been increased due to generalization of prenatal evaluation and improvement of imaging techniques. The early detection of a fetal tumor and understanding of its imaging features are very important for fetal, maternal, and neonatal care. Ultrasonography is usually used for the detection and differential diagnosis of fetal tumors, and magnetic resonance imaging is increasingly being used as a complementary study. Many fetal tumors have different clinical and imaging features compared with pediatric tumors. Although several fetal tumors may mimic other common anomalies, some specific imaging features may carry early accurate diagnosis of fetal tumors, which may alter the prenatal management of a pregnancy and the mode of delivery, and facilitate immediate postnatal treatment.
    Ultrasonography (Seoul, Korea). 06/2014;
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    ABSTRACT: To assess the diagnostic value of shear wave elastography (SWE) for prostate cancer detection.
    Korean journal of radiology: official journal of the Korean Radiological Society 05/2014; 15(3):346-55. · 1.32 Impact Factor
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    ABSTRACT: The aim of this study is to identify a patient group with a low-risk of parametrial involvement (PMI) in Stage IB1 cervical cancer using preoperative magnetic resonance imaging (MRI) parameters. In total, 190 Stage IB1 cervical cancer patients with clinically visible lesions who had undergone Type C2 radical hysterectomy and preoperative MRI were included in this study. Clinical records, pathology reports, and preoperative MRI findings were reviewed retrospectively. Of the 190 patients, 19 (10%) had pathologic PMI. The largest tumor diameter identified by MRI ranged from zero (no definite mass on the cervix) to 60mm, with a median of 21mm. Patients were identified as being either low-risk (tumor size≤25mm and no evidence of PMI, n=127) or high-risk (tumor size>25mm and/or findings indicating PMI, n=63) based on MRI parameters. The rate of pathologic PMI in low- and high-risk patients was 0.0% and 30.2%, respectively (P<0.001). Five-year progression-free survival in low-risk patients was 95.9%, which is significantly better than the rate of 85.6% for patients in the high-risk group (P=0.039). Preoperative MRI parameters can help identify patients with a low-risk of PMI and, therefore, possible candidates for trials on less radical surgery.
    Gynecologic Oncology 04/2014; · 3.93 Impact Factor
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    ABSTRACT: The aim of this study was to explore the usefulness of the resistive index (RI) on spectral Doppler ultrasonography (US) in the detection of renal cell carcinoma (RCC) in patients with end-stage renal disease (ESRD).
    Ultrasonography (Seoul, Korea). 04/2014; 33(2):136-42.
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    ABSTRACT: Characterization of intermediate-high risk adrenal incidentaloma (AI) is important because biopsy or surgery should be performed to confirm the malignancy. We investigated which parameters of F-fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) had an additive role in distinguishing malignancies in patients with incidental adrenal masses of intermediate-high risk. From January 2008 to July 2013, 52 patients with a pathologically proven diagnosis of AI were retrospectively enrolled (age=56.4±12.7 years, M : F=34 : 18; benign : malignant=14 : 38). Volumetric parameters were size and volume according to combined CT, and metabolic parameters were peak standardized uptake value (SUVpeak), maximum SUV (SUVmax), mean SUV (SUVmean), and tumor-to-background ratio (SUVmax of adrenal mass/SUVmean of liver). Metabolovolumetric parameters of metabolic tumor volume and total lesion glycolysis (TLG, SUVmean×metabolic tumor volume) were also included and compared with the diagnostic value. In addition, the highest diagnostic parameters among volumetric and metabolic parameters were combined and compared in terms of diagnostic accuracy. Compared with benign adrenal adenoma, malignant lesions showed significantly higher values of all F-FDG PET/CT volumetric, metabolic, and metabolovolumetric parameters. Size showed the highest area under the curve (AUC) of 0.759 among the volumetric parameters, and SUVpeak showed the highest AUC of 0.853 among the metabolic parameters. Among all the PET/CT parameters, TLG showed the highest AUC of 0.900, with a sensitivity of 92.1% and specificity of 78.6% at a cutoff of 12.0. The combined value of size and SUVpeak showed lower diagnostic value than TLG. We found that TLG showed the best result in distinguishing intermediate-high risk AI among PET/CT parameters. TLG can be a useful PET/CT parameter for differential diagnosis of AI.
    Nuclear Medicine Communications 03/2014; · 1.38 Impact Factor
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    ABSTRACT: Until now, several investigators have explored the value of diffusion-weighted magnetic resonance imaging (DWI) for the preoperative tumor grading of endometrial cancer. However, the diagnostic value of DWI with quantitative analysis of apparent diffusion coefficient (ADC) has been controversial. To explore the role of histogram analysis of ADC maps based on entire tumor volume in determining the grade of endometrial cancer. This study was IRB-approved with waiver of informed consent. Thirty-three patients with endometrial cancer underwent DWI (b = 0, 600, 1000 s/mm(2)), and corresponding ADC maps were acquired. Regions of interest (ROIs) were drawn on all slices of the ADC map in which the tumor was visualized including areas of necrosis to derive volume-based histographic ADC data. Histogram parameters (5th-95th percentiles, mean, standard deviation, skewness, kurtosis) were correlated with histological grade using one-way ANOVA with Tukey-Kramer test for post hoc comparisons, and were compared between high (grade 3) and low (grades 1/2) grade using Student t-test. ROC curve analysis was performed to determine the optimum threshold value for each parameter, and their corresponding sensitivity and specificity. The standard deviation, quartile, 75th, 90th, and 95th percentiles of ADC showed significant differences between grades (P ≤ 0.03 for all) and between high and low grades (P ≤ 0.024 for all). There were no significant correlations between tumor grade and other parameters. ROC curve analysis yielded sensitivities and specificities of 75% and 96%, 62.5% and 92%, 100% and 52%, 100% and 72%, and 100% and 88%, using standard deviation, quartile, 75th, 90th, and 95th percentiles for determining high grade with corresponding areas under the curve (AUCs) of 0.787, 0.792, 0.765, 0.880, and 0.925, respectively. Histogram analysis of ADC maps based on entire tumor volume can be useful for predicting the histological grade of endometrial cancer. The 90th and 95th percentiles of ADC were the most promising parameters for differentiating high from low grade.
    Acta Radiologica 12/2013; · 1.33 Impact Factor
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    ABSTRACT: Differentiation between angiomyolipoma with minimal fat (AMLmf) and non-clear cell renal cell carcinoma (nccRCC) may be difficult owing to lack of macroscopic fat in AMLmf. However, the differential points between AMLmf and nccRCC has not been well established in the literature. To evaluate quantitative triphasic multidetector computed tomography (MDCT) features that differentiate between small AMLmf and nccRCC, and to integrate them to develop a simple and easy diagnostic algorithm. This study was approved by the Institutional Review Board; informed consent was waived. Triphasic MDCT images of pathologically-proven AMLmfs (n = 24) and nccRCCs (n = 55) of 79 patients were retrospectively evaluated. Age, sex, size, long-to-short axis ratio (LSR), attenuation and enhancement degree in all phases, unenhanced tumor-kidney attenuation difference (UTKAD) in Hounsfield units (HU) were compared with Chi-square analysis, independent-samples t-test, and receiver-operating characteristic (ROC) curves. A criterion was formulated with classification and regression tree analysis (CART). Thereafter, CART-based algorithm was tested with additional interpretations from two radiologists. Intra- and inter-observer variability was analyzed with Bland-Altman analysis. LSR was greater in AMLmf than nccRCC (P < 0.001). AMLmf showed higher attenuation (all phases), CMP enhancement, and wash-out than nccRCC (P ≤ 0.001). UTKAD was greater in AMLmf than nccRCC (P < 0.001). ROC curve analysis yielded area under the curves of 0.936, 0.888, and 0.853 using UTKAD, unenhanced attenuation, and LSR. CART-based algorithm (UTKAD >7.5 HU, LSR > 1.23) predicted AMLmf with sensitivity, specificity, PPV, and NPV of 87.5%, 96.4%, 91.3%, and 94.6%. Mean intra- and inter-observer difference was -0.1/0.03 HU and -1.0/0.09 HU for UTKAD/LSR, respectively. These interpretations changed the final diagnosis in 1.3% (1/79) and 5.1% (4/79) patients for radiologists 1 and 2. Triphasic MDCT was useful for differentiating AMLmf and nccRCC. CART-based algorithm using UTKAD > 7.5 and LSR > 1.23 was simple and accurate in predicting AMLmf.
    Acta Radiologica 11/2013; · 1.33 Impact Factor
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    ABSTRACT: Chemical-shift magnetic resonance imaging (MRI) has been known to successfully differentiate adenomas from metastases. However, there has been concern that metastasis from extra-adrenal primary malignancies which contain high lipid content such as clear cell renal cell carcinoma (RCC) could mimic adrenal adenomas. To evaluate the ability of MR to differentiate adrenal adenoma from metastasis using chemical-shift imaging and MR feature analysis in patients with clear cell RCC. This study was institutional review board-approved; informed consent was waived. Eleven patients with 13 metastases and 13 patients with 15 adrenal adenomas in patients with clear cell RCC for evaluation of an adrenal mass underwent MR. Signal intensity on in- and opposed-phases, signal intensity index (SII), size, T2 SI, cystic change, necrosis, and hemorrhage were evaluated. Statistical analyses included Student t-test and Fisher exact test. If available, precontrast CT attenuation of the adrenal adenomas was measured. SII was correlated with attenuation using Pearson correlation coefficient. Mean size of adenomas was smaller than that of metastases (P < 0.002). Mean SII of adenomas (45.0% ± 24.6) was significantly greater than that of metastases (6.6% ± 4.7; P < 0.001). With a threshold of 16.5% for SII, the sensitivity, specificity, and accuracy for adenomas were 80%, 100%, and 89.2%, respectively. All six lipid-rich adenomas were diagnosed as adrenal adenoma. Three of eight (37.5%) lipid-poor adenomas were misdiagnosed as metastases. While up to 53.8% (7/13) of the metastases demonstrated cystic change, necrosis, or hemorrhage, only one (6.7%) adenoma exhibited cystic change or necrosis (P < 0.05 for all). Precontrast attenuation and SII were significantly correlated: r = -0.810 (P < 0.001). In patients with clear cell RCC who underwent MR for adrenal masses, SII and MR features such as cystic change, necrosis, and hemorrhage were helpful in differentiating adenomas from metastases.
    Acta Radiologica 11/2013; · 1.33 Impact Factor
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    ABSTRACT: OBJECTIVE. The purpose of this article is to assess the usefulness of segmental enhancement inversion on biphasic MDCT in differentiating small (< 4 cm) renal oncocytomas from chromophobe renal cell carcinomas (CRCCs). MATERIALS AND METHODS. Eighty-two patients (40 men and 42 women) with a mean (± SD) age of 54 ± 12 years (range, 21-75 years) with 27 renal oncocytomas and 55 CRCCs diagnosed by surgery who underwent contrast-enhanced biphasic CT between January 2000 and December 2011 were included. CT scans were interpreted by two radiologists who were blinded to the pathologic findings. The tumors were evaluated for size and segmental enhancement inversion. After independent evaluation, a consensus was reached by measuring the attenuation. Pathologic analysis determined the presence of fibrous septa, cystic change, hemorrhage, and necrosis. The Fisher exact test was used to evaluate the relationship between segmental enhancement inversion, tumor type, and specific pathologic changes. Interobserver concordance was evaluated with kappa statistics. RESULTS. There were no significant differences in size between renal oncocytomas and CRCCs (p = 0.458). Segmental enhancement inversion was present in 23, 20, and 21 (25.6%) of the 82 tumors according to reader 1, reader 2, and the consensus, respectively. The agreement was almost perfect (κ = 0.843; p < 0.001). Segmental enhancement inversion was more common in renal oncocytomas (63% [17/27]) than in CRCCs (7.3% [4/55]; p < 0.001). There were no significant relationships between the four pathologic changes and tumor type or segmental enhancement inversion (p = 0.351 and p = 0.126, respectively). CONCLUSION. Our study findings suggest that segmental enhancement inversion on biphasic MDCT may be useful in differentiating small renal oncocytomas from CRCCs.
    American Journal of Roentgenology 09/2013; 201(3):598-604. · 2.90 Impact Factor
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    ABSTRACT: Objectives- The purpose of this study was to report our initial experience with transabdominal high-intensity focused ultrasound (HIFU) therapy of the canine prostate and to determine the protective effect of rectal cooling during HIFU therapy. Methods- Fifteen male dogs underwent transabdominal HIFU therapy of the prostate. Transabdominal HIFU was performed on 9 dogs without using a rectal cooling device, and the remaining 6 dogs underwent transabdominal HIFU with introduction of the rectal cooling device. Magnetic resonance imaging (MRI) was performed before, immediately after, and 1 week after the HIFU procedure. Rectal changes on MRI were classified into 4 grades (grades 0-3), and a comparison of the rectal change grades on MRI between the two groups was performed with the Mann-Whitney U test. Results- The procedure failed for the first dog because of inadequate skin preparation. Of the remaining 14 dogs (8 without rectal cooling and 6 with rectal cooling), 4 showed focal signal changes in the prostate. The average rectal change grades on immediate postprocedural MRI were 2.63 for the non-rectal cooling group and 1.17 for the rectal cooling group (P = .0216). On 1-week follow-up MRI, the average grades were 1.20 for the non-rectal cooling group and 0.33 for the rectal cooling group (P = .1956). Conclusions- Transabdominal HIFU of the canine prostate was technically feasible, but the effect was limited because of anatomic and physiologic factors of the canine prostate. The rectal cooling device seems to have a protective effect on the rectum during the transabdominal HIFU procedure.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 08/2013; 32(8):1419-25. · 1.40 Impact Factor
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    ABSTRACT: OBJECTIVE. The purpose of this study was to retrospectively assess the prevalence of segmental enhancement inversion of small renal oncocytomas according to tumor size. MATERIALS AND METHODS. Thirty-three patients (19 men, 14 women; mean age, 61 years; range, 40-74 years) with 33 oncocytomas diagnosed at surgical resection who had undergone contrast-enhanced biphasic CT between January 2000 and December 2011 were included. CT scans were analyzed by two radiologists blinded to the specifics of the pathology report for size, presence of segmental enhancement inversion, enhancement pattern, and homogeneity. Segmental enhancement inversion was present when a renal mass was divided into two differently enhanced segments in the corticomedullary phase (30-40 seconds after contrast injection) with the degree of enhancement reversed in the nephrographic phase (120-180 seconds after contrast injection). The masses were further assessed for fibrous septa, cystic change, hemorrhage, and necrosis. For statistical analysis, the Pearson chi-square test and linear regression were used to evaluate the relation between the prevalence of segmental enhancement inversion and tumor size or pathologic changes. RESULTS. The mean diameter of 33 renal oncocytomas was 2.65 cm (range, 0.8-4.8 cm). There was no significant linear trend according to size (p = 0.762), although segmental enhancement inversion was significantly (p = 0.006) more common (10/12) in tumors measuring 1.5-2.9 cm. Pathologic change was present in 14 oncocytomas. There was no signifi-cant linear trend according to size (p = 0.068), but 2.5-cm and larger tumors had a significantly higher prevalence (57.9%) (p = 0.036). Segmental enhancement inversion was more common (13/19) in tumors without pathologic change (p = 0.024). CONCLUSION. Segmental enhancement inversion was a characteristic finding in our series of small renal oncocytomas and was more common in tumors measuring 1.5-2.9 cm. Pathologic changes such as central scar were more common in oncocytomas larger than 2.5 cm and may be related to the low occurrence of segmental enhancement inversion.
    American Journal of Roentgenology 05/2013; 200(5):1054-9. · 2.90 Impact Factor
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    ABSTRACT: Objectives To evaluate the efficacy and safety of repeated low-dose sonographically guided high-intensity focused ultrasound (HIFU) treatment of uterine fibroids. Methods Between April and December 2010, 24 consecutive premenopausal women with symptomatic uterine fibroids were enrolled in this study. The treatment was performed with an HIFU unit without anesthesia or sedative administration and Foley catheter insertion. The treatment was performed 40 to 70 min/d according to the tumor volume. The entire treatment was finished after 4 to 6 days of treatment. We assessed the differences in the symptom severity score, tumor volume, and contrast-enhanced volume at baseline and 1 and 3 months after treatment. The clinical success rates according to tumor volume and contrast-enhanced volume reductions and echogenicity and vascular flow changes were analyzed. The clinical success rates according to the baseline characteristics of fibroids were analyzed. We assessed adverse events during and after treatment. Results The symptom severity score, tumor volume, and contrast-enhanced volume decreased significantly after repeated low-dose HIFU treatment (P < .05). There were significant correlations between tumor volume and contrast-enhanced volume reduction and the decrease in the symptom severity score. The clinical success rates were significantly different according to the tumor vascularity on color Doppler sonography and the degree of enhancement on magnetic resonance imaging. Skin burns and other serious adverse events did not develop. Conclusions Although this preliminary report had several limitations, daily repeated HIFU treatment of uterine fibroids may be a useful and safe method and can be used as a different option for HIFU treatment in patients who prefer treatment without anesthesia or sedation.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 03/2013; 32(3):397-406. · 1.40 Impact Factor
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    ABSTRACT: To analyze magnetic resonance imaging (MRI) findings of Müllerian remnants in young females clinically suspected of Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome in a primary amenorrhea workup. Fifteen young females underwent multiplanar T2- and transverse T1-weighted MRI at either a 1.5T or 3.0T MR imager. Two gynecologic radiologists reached consensus decisions for the evaluation of Müllerian remnants, vagina, ovaries, and associated findings. All cases had bilateral uterine buds in the pelvic cavity, with unilateral cavitation in two cases. The buds had an average long-axis diameter of 2.64 ± 0.65 cm. In all cases, bilateral buds were connected with fibrous band-like structures. In 13 cases, the band-like structures converged at the midline or a paramedian triangular soft tissue lying above the bladder dome. The lower one-third of the vagina was identified in 14 cases. Fourteen cases showed bilateral normal ovaries near the uterine buds. One unilateral pelvic kidney, one unilateral renal agenesis, one mild scoliosis, and three lumbar sacralization cases were found as associated findings. Typical Müllerian remnants in MRKH syndrome consist of bilateral uterine buds connected by the fibrous band-like structures, which converge at the midline triangular soft tissue lying above the bladder dome.
    Korean journal of radiology: official journal of the Korean Radiological Society 01/2013; 14(2):233-239. · 1.32 Impact Factor
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    ABSTRACT: Immunoglobulin G4 (IgG4)-related sclerosing disease is a systemic disease characterized by extensive IgG4-positive plasma cells and T-lymphocyte infiltration in various organs. We described the imaging findings of an IgG4-related inflammatory pseudotumor in the urethra. The urethral mass showed isoattenuation on unenhanced CT images, delayed enhancement on enhanced CT images, iso- to slight hyper-intensity on T1 and T2 weighted magnetic resonance images, diffusion restriction on diffusion weighted images, and heterogeneously low echogeneity on ultrasonography.
    Korean journal of radiology: official journal of the Korean Radiological Society 11/2012; 13(6):803-7. · 1.32 Impact Factor
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    ABSTRACT: To evaluate conventional magnetic resonance imaging (MRI), prostate needle biopsy (PBx), and the combination of both tests in predicting the laterality of final specimen pathology after radical prostatectomy. A total of 574 radical prostatectomy cases that had PBx with at least 12 cores and preoperative prostate MRI with pelvic coil were included. We analyzed the clinicopathologic data with laterality based on PBx and MRI. Unilateral disease in combination was defined as unilateral cancer in PBx and at the same time MRI findings of undetectable or ipsilateral disease. Cohen's kappa (κ) was used to measure agreement between the laterality data. There were a total of 316 (55.1%) unilateral cancers detected by PBx, whereas there were 139 (24.2%) cases in the final specimen pathology. MRI resulted in 119 (20.7%) undetectable and 205 (35.7%) unilateral cancers. Cancer laterality based on final specimen pathology had only fair agreements with PBx (κ = 0.286), MRI (κ = 0.200), and their combination (k = .291). The positive predictive values to predict pathologic concurrent unilaterality were only 30.4% (96/316), 25.9% (53/205), and 34.8% (72/207), respectively. These trends were similar in low-risk cases. Preoperative PBx, MRI, and the combination of both methods had only a fair correlation with the laterality of prostate cancer (PC), even in low-risk cases. Approximately two thirds of cases diagnosed as unilateral disease by contemporary PBx, MRI, or their combination were not concurrent unilateral disease in final pathology. This should be recognized when planning nerve-sparing surgery and potentially for candidate selection for focal therapy to treat PC.
    Urology 06/2012; 79(6):1322-7. · 2.42 Impact Factor
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    ABSTRACT: To evaluate the diagnostic values of CT findings of nutcracker syndrome (NCS). Twenty seven subjects that underwent CT and renal venography, were divided into three groups based on the venographic renocaval pressure gradient (PG) and collateral veins of the left renal vein (LRV): non-compensated NCS patients with PG≥3 mm Hg (group 1, n=12), partially compensated NCS patients with borderline PG (1<3 mm Hg) and collateral veins (group 2, n=6), and control group with low PG (0-1 mm Hg) without collateral veins (group 3, n=9). The CT findings were analyzed with regard to abrupt narrowing of the LRV with an acute angle (beak sign), aortomesenteric angle between the superior mesenteric artery and aorta on sagittal images, and LRV diameter ratio (hilar-aortomesenteric). Beak sign of the LRV was found in 91.7% (11/12) of group 1, 50% (3/6) of group 2, and in 11.1% (1/9) of group 3 with the significant difference between groups 1 and 3 (P<.05, χ2 test). Mean values of all quantitative CT parameters differed significantly only between groups 1 and 3 (P<.05, one-way ANOVA test). For differentiating the non-compensated NCS from the control group, the beak sign showed 91.7% sensitivity and 88.9% specificity. Of the various CT parameters, the beak sign and LRV diameter ratio of ≥4.9 showed the greatest diagnostic accuracy (AUC 0.903, ROC analysis). Beak sign of the LRV and CT findings can be useful in diagnosing the non-compensated NCS.
    European journal of radiology 12/2011; 80(3):648-54. · 2.65 Impact Factor
  • Seung Chai Jung, Jeong Yeon Cho, Seung Hyup Kim
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    ABSTRACT: Subtype differentiation of small renal cell carcinomas (RCCs) can provide more information to surgeons and patients and get more useful information about imaging features of small renal tumors. To evaluate the usefulness of the measurement of degree and heterogeneity of enhancement in subtype differentiation of small renal cell carcinomas (RCCs) by three-phase multidetector-row CT (MDCT). We reviewed 149 pathologically confirmed small (<4cm) RCCs in 143 patients: 114 (clear cell), 17 (chromophobe), and 18 papillary (8 papillary type 1 and 10 papillary type 2). Scans in pre-contrast, corticomedullary, and nephrographic phases were obtained. We assessed the mean and standard deviation of the Hounsfield units (HU) in a region of interest (ROI) for the degree of enhancement and the heterogeneity of enhancement, respectively. We compared the attenuation values, and the degree and heterogeneity of enhancement among the subtypes. The clear cell type showed the highest enhancement and heterogeneity of enhancement followed by chromophobe and papillary types. There was a significant difference in enhancement between the clear cell and papillary types in the corticomedullary phase (P < 0.01), and between clear and non-clear cell types in the nephrographic phase (P < 0.05). Heterogeneity of enhancement showed a significant difference between clear cell and non-clear cell types in the corticomedullary phase (P < 0.05). The measurement of degree and heterogeneity of enhancement on contrast-enhanced MDCT may be a simple and useful method to differentiate between the different types of small RCCs.
    Acta Radiologica 11/2011; 53(1):112-8. · 1.33 Impact Factor
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    Seung Chai Jung, Seung Hyup Kim, Jeong Yeon Cho
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    ABSTRACT: To determine the optimal iodine concentration of contrast media for kidney multidetector computed tomography (MDCT) by comparing the degree of renal parenchymal enhancement and the severity of the renal streak artifact with contrast media of different iodine concentrations. A 16-row MDCT was performed in 15 sedated rabbits by injection of 2 mL contrast media/kg body weight at a rate of 0.3 mL/sec. Monomeric nonionic contrast media of 250, 300, and 370 mg iodine/mL were injected at 1-week intervals. Mean attenuation values were measured in each renal structure with attenuation differences among the structures. The artifact was evaluated by CT window width/level and three grading methods. The values were compared with iodine concentrations. The 370 mg iodine/mL concentration showed significantly higher cortical enhancement than 250 mg iodine/mL in all phases (p < 0.05). There was however no significant difference in the degree of enhancement between the 300 mg iodine/mL and 370 mg iodine/mL concentrations in all phases. There is a significant difference in attenuation for the cortex-outer medulla between 250 mg iodine/mL and 300 mg iodine/mL (p < 0.05). The artifact was more severe with a medium of 370 mg iodine/mL than with 250 mg iodine/mL by all grading methods (p < 0.05). The 300 mg iodine/mL is considered to be the most appropriate iodine concentration in an aspect of the enhancement and artifact on a kidney MDCT scan.
    Korean journal of radiology: official journal of the Korean Radiological Society 11/2011; 12(6):714-21. · 1.32 Impact Factor

Publication Stats

261 Citations
135.83 Total Impact Points

Institutions

  • 2012–2014
    • Seoul National University Hospital
      • Department of Radiology
      Sŏul, Seoul, South Korea
  • 2003
    • Seoul National University Bundang Hospital
      • Department of Radiology
      Seoul, Seoul, South Korea
  • 2002
    • Sungkyunkwan University
      • Department of Radiology
      Seoul, Seoul, South Korea