Computed tomographic findings in fifteen cases of anterior mediastinal teratoma are presented and comparedwith radiographic , pathologic findings. Specific CT characteristics of anterior mediastinal teratoma arepredominantly fatty mass with a denser dependent element and globular calcification in a solid protuberance intothe cystic cavity. Six cases presented above described characteristic CT findings. Four cases presented waterdensity mass with surrounding thick wall. Fat and calcific densities were present in nine and seven respectively,so these findings are frequently absent. Thick wall was present in all cases. So thick walled cyst even in theabsence of fatty or calcific densities is highly suggestive of anterior mediastinal teratoma.
Teratoma

In this animal study, comedones were induced by topical application of oleic acid onto the rabbit ear canal and the histopathologic and ultrastructural changes in response to topical application of HO and hexane extracts of red ginseng, and saponin were measured. No microscopical difference was observed between treatment groups. Nucle ir remnants were observed in the horny cell layer as well as the thinning of the granular cell layer. Scattered and decreased keratohyaline granules were also noted. Six weeks after initiation of treatment, we observed the thinning of epidermis and veappearance of granular cell layer with normal keratohyaline granules. After treatment, scanning electron microscopy showed a decrease in the size of comedones, and loosened and desquamating horny cells in the comedones. From the above results, it could be concluded that Panax ginseng extracts might have effects on the keratinization process of the skin.
Animals ; Ear Canal ; Epidermis ; Microscopy, Electron, Scanning ; Oleic Acid ; Panax* ; Saponins ; Skin

To evaluate the reliability of MR imaging in tissue characterization and depiction of tumor boundaries, we performed MR-pathologic correlation using parosteally implanted VX-2 carcinoma in 17 rabbit thighs. T1-weighted, T2-weighted and Gd-DTPA enhanced T1-weighted axial images were obtained 10-30 days after tumor implantation. After the animals were killed, frozen and sectioned along the MR imaging planes, and histopathologic examinaton were done. For accurate MR-pathologic correlation, rabbits were fixed on the cardboard plate to minimize position change during the procedures. Tumor boundaries depicted on MR images were larger than those depicted on the specimen. Small tumors were surrounded by capsule-like loose connective tissue. Loose connective tissue became compact with tumor growth. This connective tissue showed high signal intensity on both T2-weighted and Gd-DTPA enhanced T1-weighted images. Muscle atrophy with fatty tissue accumulation around the tumor also contributed to the high signal intensity on MR images. Peritumoral edema and inflammatory reaction were not remarkable. Six of 8 cases with bone marrow fibrosis were detected on MR images. We concluded that peritumoral loose connective tissue and muscle atrophy exaggerated the size of experimentally induced malignant musculoskeletal tumors on MR images.
Adipose Tissue ; Animals ; Connective Tissue ; Edema ; Gadolinium DTPA ; Magnetic Resonance Imaging ; Muscular Atrophy ; Primary Myelofibrosis ; Rabbits ; Thigh

This experiment was performed to study the morphological responses of the thymic cortex of the mice after administration of BCG. Healthy adult mice weighing 25gm each were divided into normal and experimental groups. BCG[0.03X108-0.32X108 CFU] were injected subcutaneously to the animals every other day, and animals were sacrificed at 4 days, 1 week, 2 weeks and 8 weeks following the first injection. Thymus were removed immediately after sacrifice and transferred to cold phosphate buffered 2.5% glutaraldehyde-1.5% paraformaldehyde solution[pH 7.3], and cut into small pieces. Tissue samples were fixed for 2-3 hours in the same fixative, postfixed with phosphate buffered 1% osmium tetroxide solution[pH 7.3], dehydrated in a graded series of alcohol, and embedded in araldite mixture. Ultrathin sections stained with uranyl acetate and lead citrate were observed with a JEM 100CX-II electron microscope. The observed results were as follow : 1. In the early BCG treated groups, a few eosinophile leucocytes were observed, but more eosinophils were observed in later groups. Some elongated and bar-shaped lysosomes with eletron lucent gap were often obserced in the macrophages. 2. Cortical population of thymocytes in the thymus were reduced, whereas territoris of the epithelial reticular cells were expanded especially in 2 weeks and 8 weeks groups. Some portion of the thymic cortex exhibited large intercellular spaces, and a few nuclear bodies filled with materials of medium density were observed in the epithelial reticular cells. 3. In the 8 weeks groups, macrophages, plasma cells and eosinopile leucocytes and developing eosinophile leucocytes were often observed in the thymic cortex. Distended cisternae of granular endoplasmic reticula and newly forming prosecretory granulses in the Golgi complex were ovserved in som plasma cells. From the above results, it was suggested that repeated treatment with BCG could induce disturb the maturation and differentiation of the T lymphocytes. In turn, BCG, if repeatedly injected, may disturb the immunological medchanism.
Adult ; Animals ; Citric Acid ; Eosinophils ; Extracellular Space ; Golgi Apparatus ; Humans ; Lysosomes ; Macrophages ; Mice* ; Mycobacterium bovis* ; Osmium Tetroxide ; Plasma Cells ; T-Lymphocytes ; Thymocytes ; Thymus Gland

Renal arterial embolization was induced experimentally in rabbits using autologous blood clot, Gelfoam, bariumsulfate, Ivalon(Polyvinyl alcohol)and ethanol. Microvascular changes were studied angiographically,microangiographically and histopathologically. The results were as follows: 1. The microangiographic findings ofrenal artery embolization were arterial occlusion, irregular arrangement, spiralling, dilatation, narrowing andcollateral vessel formation. 2. Recanalization of embolized vessels were noted after injection of autologous bloodclot and Gelforam only. 3. Collateral vessel formations were demonstrated in entire cases of renal arterialembolization (36/37). 4. After injection of Ivalon, recanalization of embolized vessel was not demonstrated butcollateral vessel formation were demonstrated microangiographically in all cases. 5 After injection of ethanol,collateral vessels were poorly developed microangiographically than other groups. 6. Embolic effect of ethanol wasnoted in central vessel but as well as in peripheral vessel. It was considered that ethanol is the most effectiveagent for permanent renal arterial occlusion.
Arteries ; Dilatation ; Ethanol ; Gelatin Sponge, Absorbable ; Rabbits

The hepatic artery was embolized with absolute ethanol in 1 mongrel dogs to evaluate the embolic effect andsafety of this material. Follow up angiography and liver function test were performed at 15 minutes, 1 week and 4weeks after embolization. Retrograde cholangiography, microangiography and pathologic examination were done at 4weeks after embolization. The result was as follows: 1. Sequential angiography showed successful and persistentocclusion of intrahepatic arteries at different levels, and reconstitution of the intrahepatic arterialcirculation via collaterals. 2. Microangiography revealed avascular area in 5 cases. But in incompletely infactedare there showed tortuous hepatic arteries, decreased perfusion of sinusoid and microcolaterals through theinterlobular arteries, capsular arteries and peribiliary vascular plexus. In one case sparse peribiliary plexuswas observed. 3. Retrograde cholangiography revealed findings of cholangitis on involved segment. 4. The absoluteethanol was effective for achieving a permanent occlusion of intraheptaic arteries but caused damage on sinusoidand hepatic parenchyme, and on peribilary vasucular plexus resulting in sclerosing cholangitis. So in furtherclinical application, caution would be necessary to superselect the tumor supplying artery to avoid unnecessaryparenchymal damage.
Angiography ; Animals ; Arteries ; Cholangiography ; Cholangitis ; Cholangitis, Sclerosing ; Dogs ; Ethanol ; Follow-Up Studies ; Hepatic Artery ; Liver Function Tests ; Perfusion

The receiver operating characteristic (ROC) curve analysis was done to evaluate the effects of digital image processing techniques on the detectability of simulated pulmonary nodules and cysts in chest radiographs. Image processing techniques used were the contrast inversion, unsharp masking, and filtered equalization method. Simulated pulmonary nodules and cysts were generated by the computed program using Turbo-C language for personal computer. Each processed and unprocessed image sets of sixty images with pulmonary nodules and cysts and one hundred and twenty normal images were analyzed by three board-certified radiologists and four senior residents training in diagnostic radiology by five rating category. Area under the ROC curve was calculated using the trapezoidal rule. Mean area under the ROC curve of seven radiologists of the unprocessed image was 0.6360±0.0583, contrast inversion was 0.5660±0.0478, unsharp masking was 0.7534±0.0355 and filtered equalization was 0.6915±0.0472. Unsharp masking(p<0.01) and filtered equalization image(p<0.05) was statistically significant than unprocessed image. Digital chest radiographs processed by the unsharp masking method significantly increased the detectability of simulated pulmonary nodules and cysts overlapped with mediastinum and pulmonary cysts in free lung fields.
Lung ; Masks ; Mediastinum ; Methods ; Microcomputers ; Radiography, Thoracic* ; ROC Curve ; Thorax*

PURPOSE: To determine the MR imaging findings of synovial sarcoma, with emphasis on the signal characteristicsof pathologically correlated T2-weighted images. MATERIALS AND METHODS: MR images of 14 cases ofpathologically-proven synovial sarcomas were retrospectively reviewed and correlated with the histopathologicfindings. We analyzed the signal intensity of T1- and T2-weighted images and the incidence of triple signalintensity, and evaluated the frequency of fluid-fluid levels, internal fibrous septa, calcification, the invasionof bone or neurovascular bundles and the involvement of joint capsules, as well as the size, location and marginof the tumors and pattern of contrast enhancement. RESULTS: Necrosis, cystic change or hemorrhage was suggested in11 cases, ten of which showed triple signal intensity, and in all cases, was pathologically confirmed. Fluid-fluidlevels were found in three cases and internal septa in ten. In four cases, maximum diameter was less than 5cm, andin nine, was greater than this. No mass was detected in one case. The tumor was located in the low extremity(n=9),pelvic girdle and hip joint area(n=2), scapular(n=1), shoulder joint area(n=1), and scalp(n=1). Eleven casesshowed a relatively well-defined margin and nine showed lobulation. Except in the area of necrosis and cysticchange, the pattern of contrast enhancement was diffuse and inhomogenous. Bony invasion was detected in two cases,neurovascular encasement in four, calcification in four, and joint capsule invasion in four. CONCLUSION: OnT2-weighted images, synovial sarcoma frequently showed triple signal intensity and internal septa with fluid-fluidlevels ; this was induced by cystic changes due to necrosis and hemorrhage.
Hemorrhage ; Hip Joint ; Incidence ; Joint Capsule ; Magnetic Resonance Imaging* ; Necrosis ; Retrospective Studies ; Sarcoma, Synovial* ; Shoulder Joint

Pulmonary epithelioid hemangioendothelioma (PEH), originally termed an intravacular bronchioloalveolar tumor, is a rare pulmonary neoplasm with a vascular origin and slow rate of malignancy. It affects various organs such as the liver, the central nervous system, lung, etc. Clinically, pulmonary epithelioid hemangioendothelioma has been considered to be a borderline malignancy, a generally indolent and nonaggressive tumor that displaes the pulomonary parenchyma over a number of years by slowly enlarging the tumor nodule. The clinical course of PEH is known to be usually benign. Here we report an unusual case of PEH that was highly malignant and was eventually fatal. The PEH was confirmed by microscopic analysis and hmmunohistochemical staining of CD31+(a membrane receptor and a sensitive and specific marker for vascular lesions) from an open lung biopsy specimen.
Biopsy ; Central Nervous System ; Hemangioendothelioma, Epithelioid* ; Liver ; Lung ; Lung Neoplasms ; Membranes

PURPOSE: We analysed CT findings of thyroid mass to determine the difference between a benign and a malignant mass and to evaluate the differential findings, if any. MATERIALS AND METHODS: The subjects were 87 cases with apathologically proven thyroid mass (malignancy in 66 cases, benign mass in 21 cases). CT findings were retrospectively analysed. For the primary masses, bilaterality, size, margin, attenuation of the mass, spotty portion with distinct high attenuation(which may suggest calcification), necrosis, cystic change, solid portion within the cyst, and invasion of adjacent structures were evaluated. For the lymph nodes, size, high attenuated spotty portion, necrosis, cystic change, and solid portion within the cyst were evaluated. CT findings of thyroid masses and lymph nodes were evaluated in order to determine whether these were benign or malignant. Statistical analysis was performed using the Mann-Whitney U-Wilcoxon rank sum test. RESULTS: In malignant masses, compared with benign, an indistinct margin of the mass(48% vs 19%), invasion of adjacent structures(53% vs 0%), and associated lymph node enlargement(50% vs 0%) were more frequent. With regard to bilaterality, size, attenuation, high-attenuated spotty portion(which may suggest calcification), necrosis, cystic change, and solid portion within the cyst, there was no significant difference between benign andmalignant masses. In masses of the former type, enlarged lymph node or invasion of adjacent structure were not seen at all. When the papillary solid portionwithin the cystic mass was additionally evaluated, papillany carcinoma was the most common finding(77% 14\18). CONCLUSION: General findings of malignancy such as margin, invasion of the mass, and lymph node enlargement are of help in the differential diagnosis of a malignant mass. High attenuated spotty portion, which may suggest calcification within the mass, or size of the mass are non-specific findings, and are not helpful in differential diagnosis. The papillary solid portion within the cyst of the mass could suggest papillary carcinoma as a first possibility and could be helpful in differential diagnosis.
Carcinoma, Papillary ; Diagnosis, Differential* ; Lymph Nodes ; Necrosis ; Thyroid Gland*