정대철 교수

Renal papillary necrosis is not a pathologic entity but rather a descriptive term for a condition--necrosis of the renal papillae--that has various possible causes. The renal medulla and papillae are vulnerable to ischemic necrosis because of the peculiar arrangement of their blood supply and the hypertonic environment. The etiology of renal papillary necrosis includes diabetes, analgesic abuse or overuse, sickle cell disease, pyelonephritis, renal vein thrombosis, tuberculosis, and obstructive

Penile Doppler ultrasonography is a high-performing, noninvasive or minimally-invasive imaging modality that allows the depiction of the normal anatomy and macroscopic pathologic changes in real time. Moreover, functional changes in penile blood flow, as seen in erectile dysfunction (ED), can be analyzed using color Doppler ultrasonography (CDUS). This review article describes the normal sonographic anatomy of the penis, the sonographic technique for evaluating ED, the normal phases of erection,

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.

We propose a computer-aided classification system for distinguishing fp-AML from ccRCC using machine learning classifiers with quantitative texture features. Our contribution is to investigate the proper combination between the quantitative features and classification systems on the CE MDCT images. In experiments, it can be demonstrated that (a) the features based on histogram characteristics on bright intensity region and texture patterns on inhomogeneity inside masses were selected as key feat

OBJECTIVES: To provide reference values of intrarenal venous impedance index (VII) measured with duplex Doppler ultrasonography in a healthy adult population and to assess the usefulness this index for evaluating the functional status of kidney in patients with diabetic nephropathy (DN). METHODS: Between May 2005 and December 2009, Doppler ultrasonography of both kidneys was performed in 164 healthy volunteers (controls) and 58 patients with DN. Renal interlobar and segmental vein Doppler wavefo

OBJECTIVE: We wanted to assess the MR imaging findings of ovarian cystadenofibroma and cystadenocarcinofibroma, and we wanted to find clues for making the differential diagnosis between them. MATERIALS AND METHODS: The MR images of 12 pathologically proven cystadenofibromas and two cystadenocarcinofibromas were reviewed, with a focus on the internal architecture, signal intensity and enhancement. RESULTS: All the tumors appeared as multilocular cysts, except for a single unilocular cystic mass a

In the xenografted prostate cancer model, the ADC values of the solid portion of the tumors are significantly correlated with tumor necrosis and MVD of the pathologic specimens. The ADC values may be utilized as surrogate markers for the noninvasive assessment of tumor necrosis and MVD in high-grade prostate cancer.

PURPOSE: To develop an image-based classification system for seminal vesicle lesions (SVL) to detect seminal vesicle invasion (SVI) in prostate cancer and to evaluate whether pattern analysis of SVL with MR imaging could improve the accuracy of evaluating SVI. MATERIALS AND METHODS: The MR images of 217 patients who had undergone retropubic radical prostatectomy (RRP) due to prostate cancer were retrospectively analyzed by two uroradiologists, focusing on SVL. The SVL on T2-weighted sequences wa

Neurilemmoma of the glans penis is rare, and no imaging findings have been reported. A case of neurilemmoma of the glans penis is presented. Ultrasonography (US) and magnetic resonance imaging revealed a well-defined small mass in the glans penis. The mass appeared hypoechoic on gray-scale US and hypervascular on color Doppler US. Magnetic resonance imaging revealed high signal intensity of the mass on a T2-weighted image and strong enhancement on a contrast-enhanced T1-weighted image.

Objective: To assess the relationship between apparent diffusion coefficient (ADC) values on diffusion-weighted magnetic resonance (MR) imaging and pathologic measures of a tumor using a prostate cancer xenograft model. Materials and Methods: Eighteen athymic nude mice with 36 PC-3-induced tumors were sacrificed to obtain specimens immediately after MR imaging in order to compare the findings on MR images with those seen on pathological specimens. Using a high-field small-animal MR scanner, T1-