| Eun Chul Chung | 12 Articles |
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[English]
The purpose of this study was to analyze the MR findings of intramedullary tumors and review the literatures for evaluating of characteristic findings of each intramedullary tumors. We experienced eight intramedullary tumors from March 1993 to February 1995, including four astrocytomas two ependymoma, one hemangioblastoma, and one cavernoma. MR images were get by 1.5T GE Signa and analized retrospectively. Intramedullary tumor was demonstrated by MR images in eight patients. They were five men and three women ranging in age from 3 to 56 years and complained both motor and sensory changes and symptom duration was between 6 months and 3 years. Ependymoma showed diffuse homogenous enhancing mass at the level of thoracic cord(T2-3) and thoracolumbar level(T11-L2) without cystic change, One had hemorrhage within the mass and massive leptomeningeal metastasis at all spinal cord and brain. Among astrocystomas, one case at the cervical cord unusually revealed hemorrhage in the mass and regional large syrinx. The other one occured at the conus medullaris portion and showed well-defined mass and intratumoral cystic change. We also experienced rare intramedullary hemangioblastoma, which demonstrated typical signal voided vascular structures revealed homogenous enhancing mass. A very rare intramedullary cavernoma at the level of cervical cord showed typical dark signal hemosiderin rim and variable staged hemorrhage in the mass. Although, MR imaging appearance of intramedullary tumors is nonspecific, and it is often impossible to differentiate with certainty between the various possible tumors, especially ependymomas and astrucystomas. However, MR findings of hemangioblastoma and cavernoma are specific and possible to diagnose. MR imaging is the unquestioned technique of choice in demonstrating and differentiating the intramedullary tumors.
[English]
The cavernous malformation is increasingly recognized as a vascular malformation of the brain that presents with seizures, hemohhage, or neurologic deficit. We have identified 24 lesions in 12 patients that were diagnosed cavernous malformation of the brain based on the findings of follow-up magnetic resonance image and sugical biopsy. The location of the lesions were the supratentorial area in 20 and infratentorial area in 4. Ten lesions were seen at the periventricular white matter. Combined venous angioma was noted in 4 patients. The appearance of the lesions classified by signal intensities on MRI was divided into reticular pattern in 11, punctate pattern in 9, hematoma pattern in 3, and cystic pattern in one. Recent hemorrhage was identified at 9 lesions that classified into extralesional type in 5 and intralesion type in 4. Among 9 hemorrhagic lesions, eight lesions were located at the periventricular white matter and six lesions showed reticular patterns. We concludedthat the correlation between the evidence of recent hemorrhage and location and pattern of the lesions should be evaluated to predict possibility of rebleeding of the cavernous malformation.
[English]
To report e experience of performing embolization procedure of aneurysms with mechanical detachable coils(MDC). Two patients underwent embolization of eneurysms with mechanical detachable coils. One patient who had an aneurysm in the left posterior inferior cereberllar artery(PICA) underwent the embolization procedure with one spiral coil(4mm×80mm) and another patient who had an aneurysm in the left posterior(P-comm.) communicating artery aneurysm underwent the embolization procedure with four spiral coils(three 5mm×8mm and one 3mm×80mm). Immediately after coil placement in the PICA the flow of contrast in the PICA reduced significantly. It may resulted from compression of the origin of PICA by the coil-packed aneurysm. The posttreatment course was not uneventful In case of P-comm. aneursym, the last coil(3mm×80mm) which embolized in the aneurysm, escaped from the aneurysm into the left internal carotid artery. Thej retrieval of the coil in the internal carotid artery with 3F microretrieval cathter was sucesfully performed. This preliminary experience suggests that the embolization procedure with mechanical detachable coils is a usful modality of treatment of cerebral aneurysm in case ofinoperable cases.
[English]
Intravascular embolization of fragments of indwelling intravascular diagnostic polyethylene catheter continues to occur. This causes many complications such as sepsis, thromboembolism, endocarditis and even perforation of cardiac chambers. The author experienced 3 cases of successful retrieval of intravascular iatrogenic catheter foreign bodies which were iocated in right pulmonary artery and inferior vena cava, using loop-snare technique. Percutaneous transluminal retrieval of catheter foreign bodies were underwent within 30minutes. There were no complications following retrieval of foreign bodies. This study suggests that the loop-snare technique is a safe and effective method for retrieval of iatrogenic foreign bodies in the great vessels. Citations Citations to this article as recorded by
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Magnetic resonance(MR) is the most widely used diagnostic tool for the meniscal tears. 160 images of menisci of 30 patients and 10 normal subjects were photographed with coronal and sagittal planes and with narrow and conventional wide window settings. To access the diagnostic efficacy of imaging planes and the window settings, MR images of two window settings with coronal and sagittal planes of menisci were interpreted by four experienced observers. Images were graded on a five-point scale to enable receiver operating characteristic (ROC) curve analysis. The ROC curves constructed from the coronal plane were similar to those of the sagittal images. The area of under ROC curve constructed from the narrow window setting was inferior to one from the wide window settings. There was no difference of diagnostic performance between four observer to detect meniscal abnormality. This suggests that there is no globally significant improvement in the detection of meniscal tear when narrow window setting are used for interpretation, and there is probable improvement when both coronal and sagittal images are used for meniscal MRI.
[English]
The diagnosis of cervical incompetency is routinely accomplished by reviewing the clinical history and pelvic examination subjectively. Rescently by using ultrasonography. the objective method in diagnosis of cervical incompetency was developed. Especially, the transvaginal sonography can provide clear visualization of uterine cervix with an empty bladder without distrosion of cervix which was developed when abdominal sonography with distended bladder. So author performed the study in 46 cases of pregnant women of which menstrual age was 12 weeks to 36 weeks(normal control group 36 cases, risk group 11 cases) during the period of May, 1992 to Febburary, 1993. And these two groups were performed trasvaginal sonography and measured length and diameter of cervix. And the result were follows ; 1) The mean age was higher in risk group than normal control group, the gestational age was not significantly different between two groups, and the gravity and parity was higher in risk group than normal control group. 2) As measuring the length and diameter of cervical canal by transvaginal sonogram in nullipara and multipara in normal control group, each measurements were not significantly different between nullipara and multipara. 3) The mean length of cervix by transvaginal sonography was 3.0±0.97cm in risk group, 4.7±0.89cm in normal control group and the cervical length was significantly shorter in risk group than normal control group(P<0.01). 4) The mean diameter of cervix by transvaginal sonogram was 2.0±0.37cm in risk group, 0.5±0.21cm in normal control group and the diameter of cervix was significantly greater in risk group than normal control group(P<0.01). Transvaginal sonographic measurement of cervical length and diameter in diagnosis of incompetent internal os of cervix is noninvasive and relatively objective method.
[English]
The purpose of this study is to determine the utility of cardiac cine-MRI in the measurement of left ventricular volume and cardiac output. The results of cardiac cine-MRI were compared with those obtained by 2-dimensional echocardiography in 19 normal pediatric subjects. The results are as follows: 1) The mean values of the parameters(end-diastolic volume, end-systolic volume, ejection fraction, stroke volume, stroke index, cardiac output, and cardiac index) which were calculated by cardiac cine-MRI, demonstrated excellent agreement with the results of 2-dimensional echocardiography(p>0.05). 2) Significant linear correlation was made when each parameter was compared between 2-dimensional echocardiography and cardiac cine-MRI(p<0.05). 3) End-diastolic and end-systolic volume which were estimated by 2-dimensional echocardiography and cardiac cine-MRI, were significantly increased according to increasing age or body weight(p<0.05). The results of the study indicate that cardiac cine-MRI is likely to become a useful diagnostic modality to evaluate anatomic abnormalities in congenital and acquired cardiac diseases and to measure left ventricular volume and cardiac functions. Citations Citations to this article as recorded by
[English]
Magnetic resonance imaging(MRI) of 47 patients with surgically confirmed lumbar disk herniation at 62 levels was studied retrospectively to evaluate the significance of MRI in diagnosis of lumbar disk herniation. Prolapsed type of lumbar disk herniation is 47 cases(76%). lumbar disk herniation at L4-L5 level is 33 cases(53 %) and posterolateral herniation is 54 cases(87%). 6 cases(10%) of lumbar disk herniation in MRI were not matched with operative findings, due to lumbar scoliosis(4 cases) and lumbarization of S1 (2 cases). Associated abnormalities are 4 cases of Schmorl's nodule and 2 cases of spondylolisthesis, MRI shows excellent sagittal image and can differentiate extruding type of lumbar disk herniation from prolapsed type. The result of the study indicates the MRI is likely to become the initial procedure of choice for evaluating patients with suspected lumbar disk herniation. If clinically incompatible with MRI findings, it is desirable that CT and/or myelography are complementary to MRI study.
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Hysterosalpingography is a valuable diagnostic tool in the investigation of the uterine and tubal factors of female infertility. Author evaluated the effect of different iodinated contrast agents on the fallopian tube and adnexal tissue in 16 rabbits. Lipiodol, an oil-soluble agent, was used for 4 rabbits. The following water soluble contrast agents were used for 12 rabbits: iothalamate meglumine 60%, diatrizoate sodium, and iopromide. The agents injected through the catheter placed in the fallopian tube. Fallopian tubes and peritoneal cavities were evaluated histologically. Iothalamate meglumine and diatrizoate sodium contrast agents, were associated with mild to moderate Inflammation and edema. Iopromide. which has low osmolarity, produced mild inflammation compared to ionic contrast agents. Use of oil-soluble contrast medium resulted in fibrous adhesion, moderate to marked inflammation and tissue edema in fallopian tubes andperiovarian tissues. The safety of oil-soluble contrast agents for hysterosalpingogrpahy is questioned. Therefore, contrast agents with low osmolarity are suitable for use in hysterosalpingography.
[English]
The VX-2 Carcinoma was used to create a model of the orbital metastasis in rabbits. 0.5ml suspension containing 20-30×107 cells of VX-2 Carcinoma was injected into the 36 orbits of 18 rabbits. With 3 to 4 day interval. tumors were evaluated with ultrasonography and carotid arteriography. Ultrasonography findings revealed a well-defined. hyperechoic mass with central necrosis. and invasion of the orbital wall and the optic canal. The tumors appeared hypervascular lesion with carly venous drainage and vascular sweeping on carotid arteriography. Pathologically, the tumor consisted of compacted high mitotic adenocarcinoma. with large vacuolated nuclei and profuse cytoplasm. Massive infiltration into the orbital wall and the retrobulba also found. This animal model quickly. consistently and inexpensively produced orbital mass lesions. It is well suited for ophthalmologic oncologic research focused imaging modalities. and multimodality of treatment approach to the orbital mass lesion.
[English]
Hyperthermia can enhance the radiation effect as a synergistic effect in combination of X-ray irradiation and hyperthermia. Hyperthermia sensitizes radioresistant S-Phase cells in cell cycle and inhibits cellular recovery from sublethal damage. Author fabricated 100 watt, 2450 MHz microwave applicator for hyperthermia, planned the methods and conditions of heating, and measured the temperature by using Agar phantom as a preliminary test. For biological examination, 90 rats were divided into 4 groups as hyperthermia, X-ray irradiation(6, 8 and 10 Gy), X-ray irradiation with hyperthermia, and normal control groups. Histologic examination of the liver was done. The results were as followings: 1) In hyperthermia group, there was mild degeneration of hepatocyte and mild degree of edema in portal tracts. 2) Mild degeneration of hepatocyte was appeared in the liver after 15 days of 6 Gy X-ray irradiation, and mild necrosis of hepatocyte with disarray after 60 days of 8 Gy irradiation. the findings were more severe in the group of 10 Gy irradiation. 3) In the group combined modality of irradiation plus hyperthermia, mild degneration of hepatcoyte was appeared after 15 days of 6 Gy irradiation, and mild necrosis of hepatocyte with disarray after 60 days of 8 Gy irradition. 4) The thermal enhancement ratio (TER) of the liver, which was calculated at the end point of disarray and necrosis of hepatocyte, was 1.0 in the group of combined modality.
[English]
Percutaneous fine needle aspiration biopsy of lung masses is a simple and the most frequently used interventional procedure in radiologic department. Its use is progressively increased, relating to the improvemt of fluoroscopy and types of aspiration needle, and the advances in cyto-pathology. Over a period of recent 2 years, 21 cases of lung mass underwent percutaneous aspiration biopsy were analysed. 14 cases were proven as malignancy. 3 cases were benign lesions. Open lung biopsy and operation permit the exact pathology of the remaining 4 cases as malignancy. The overall diagnostic accuracy was 81% (17/21). Author recommended that the percutaneous fine needle aspiration biopsy must be inital procedure in diagnostic work-up of pulmonary masses.
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, Eun Chul Chung
