A study on the radiation effect on microvasculature of N-methyl-N-Nitrosourea-induced mammary carcinoma in rats

Mammary carcinoma was induced in rats by itravenous injection of N-methy-N-Nitrosourea. Microangiography was perfromed to evaluate the microvascular alterations in mammary carcinoma after irradiation. The tumors were givena single dose of 1.400 rads using Co-60 telethrapy unit with field size of 4 x 4 cm at 40 cm SSD. The dose ratewas 147.5 rads per minute. Microangiography was performed prior to irradiation and at one, two, and four weeksfollowing irradiation. The results are as follows: 1. Before irradiation, mammary carcinoma in rats tended to formlobules and the basic vasculature consisted of peripheral vascular pattern with central penetrating vessels. Theperipheral vascular pattern was always richer than that of the center. Irregular and tortuous vessles stretchedfrom the periphery into the center of lobule. 2. One week following irradiation, an increase in the number ofsmaller, tortuous vessels and decreased intervasular distance were obseved in the central portion of each lobule.This finding seems to be due to an improved filling of some previously existing but unfilled vessels. This maylead to improved metabolic changes and reoxygenation. 3. Later's changes of microvasculature after irradiation aretortuosity, irregularity, narrowing, abrupt tapering, fragmentation, and extravasation. These findings progressedafter a lapse of time. 4. The results can be considered as the microangiographic demonstration of the fact that reoxygenation after irradiation is mainly due to dilatation of the collapsed tumor vessels.

Normal mediastinal lymph node size and shape; CT and cadaver study

With the view point of size, shape and arrangement pattern, authors present normal mediastinal lymph node fromthe analysis of 61 cases of CT scan and multidirectional section of 2 cadavers. The results were as follows: 1.Transverse diameter of the lymph nodes, demonstrated in cadaver section, was 3 to 6mm in upper paratracheal areaand 5 to 14mm in juxta-carinal and AP-window area. Arrangement of the lymph nodes showed tendency of longitudinaldirection in lower paratracheal, and juxtacarinal area, while that of AP window showed tendency of AP direction aslong axis. 2. Mean and the largest size of the lymph nodes demonstrated in CT scan were 3.7mm, 8mm in upperparatracheal area, and 6mm, 12mm in lower paratracheal area, and 7.1mm, 14mm in juxtacarinal area, and 6.3mm and11mm in aorticopulmonary window area. 3. Size fo the lymph nodes in CT scan showed linear increasing tendencyaccording to increasing age(y=0.32, p<0.005). 4. Shape of the lymph nodes in CT scan were mostly round in upperparatracheal area while that of aorticopulmonary window showed higher incidence of oval and elongated shape. 5.Recommended size criterior of abnormal lymph node is 10mm in upper paratracheal are and 15mm in the other area.

Computed tomography of bronchioloalveolar carcinoma showing open bronchus sign

Open brochus with diffuse narrowing, stretching, and leafless tree appearance of the bronchi is the well know bronchographic criterior of bronchiloalveolar carcinoma. Though similar findings are expected in CT, authors couldfind no report concerninng the open bronchus sign of bronchioloalveolar carcinoma demonstrated by CT., Authorspresents CT of bronchioloalveolar carcinoma showing lobar or segmental distribution and patent bronchus within thetumor mass.

CT findings of the mediastinal tumors; excluding mediastinal granuloma and primary carcinoma

Computerized Tomography can make accurate diagnosis in most of the mediastinal tumors and cysts by assessingtheir location, shape and internal architecture. Authors analysed and present CT findings of 89 surgically provenmediastinal tumpors and cysts that were studied and treated in Seoul National University Hospital during recent 5years. The results are as follows; 1. The most common tumor was teratoma(25 cases). Neurogenic tumor (20 cases),thymic tumor or cyst (16 cases), lymphoma(7 cases), bronchogenic cyst (6 cases), intrathoracic goiter (6 cases),pericardial cyst(3 cases) and cystic hygroma(2 cases) were next in order of frequency. 2. The most constant findings of teratoma was thick walled cystic area(100%), while pathognomonic fat and calcified density were seenonly in 52% and 48% of cases, respectively. 22 cases were located in anterior mediastinum, 2 cases were inposterior mediastinum and a case is in middle mediastinum. 3. There were 20 cases of neurogenic tumor consiting of6 neurilemmomas, 7 ganglioneuromas, 4 neurofibromas, 1 ganglioneuroblastoma, 1 neuroblastoma and 1 malignantschwannoma. Most of them were located in posterior mediastinum with exception of 2 neurilemmomas arising from leftvagus nerve and left recurrent laryngeal nerve in middle mediastinum. Cystic change was seen in 2 cases ofneurilemmoma and in a case of ganglioneuroma. Calcification was seen in 3 cases, of neuroblastoma, aneurilemmoma,and a ganglioneuroma. 4. There were 11 cases of thymoma showing homogeneous solid mass with speckeldcalcification in 4 cases and irregular cystic change in 3 cases. 2 cases were invasive thymoma and myastheniagravis was present in 4 cases. A case of thymolipoma and a case of thymic cyst were included. 5. Lymphoma(2Hodgkin's and 4 non-Hodgkin's) appeared as lobulated, matted mass in anterior mediastinum especially inprevascular area expnading bilaterally. 6. Intrathoracic goiter appeared as slingtly high density mass within termingled calcification and cystic area in 5 cases of secondary goiter and homogeneous high densitymass(100-110 H.U. in precontrast scan) in a case of primary goiter. 7. Among the 6 bronchogenic cysts, 3 werelocated in subcarinal area, 2 were above carina and one was in left hilar area. 3 cases showed high CT number morethan 70 H.U. and others showed water density. 8. 3 cases of pericardial cyst were located in right cardiophrenicangle and all of them showed water density. 9. 2 cases of cystic hygroma were located in superior mediastinum,with extension to lower neck and all of them showed water density.

ECG gated magnetic resonance imaging in cardiovascular disease

Using KAIS 0.15 Telsla resistive magnetic imaging system, ECG gated magnetic resonance (MR) image of variouscardiovascular disease was obtained in 10 patients. The findings of MR image of the cardiovascular disesase wereanlaysed and the results were as follows: 1. In 6 cases of acquired and congenital cardiac disease, there were 2cases of myocardial infarction, 1 case of mitral stenosis and 3 cases of corrected transpossition of greatvessels. The others were 3 cases of aortic disease and 1 case of pericardial effusion with lymphoma. 2. Myocardialthinning left ventricular aneurysm were detected in MR images of myocardial infarction. The left atrium was welldelineated and enlarged in the case of mitral stenosis. And segmental analysis was possible in the cases ofcorrected transposition since all cardiac structures were well delineated anatomically. 3. In aortic disease, thefindings of MR image were enlarged lumen, compressed cardic chambers in ascending aortic aneurysm, intimal flap,enhanced false lumen in dissecting aneurysm and irregular narrowing of aorta with arterial obstruction inTakayasu's arteritis. 4. Pericardial effusion revealed a conspicuous contrast with neighboring meidastinal fat andcardiac wall due to it low signal encircling cardiac wall. 5. ECG gated MR image is an accurate non-invasive imaging modality for the diagnosis of cardiovascular disease and better results of its clinical application areexpected in the futher development in the imaging system and more clinical experiences.

Radiological Findings of Pulmonary Aspergillosis

The pulmonary aspergillosis is a group of three separate diseases, comprising invasive aspergillosis, aspergilloma, and allergic bronchopulmonary aspergillosis, or a disease process in which one of three entities overlap with another process such as mucoid impaction, pulmonary infil t ration with eosinophilia, bronchocentric granulomatosis, microgranulomatous hypersensitivity, or asthma. The radiological findings of 24 cases of pulmonary aspergilloss diagnosed and treated at Seoul National University Hospital during the past 7 years were analyzed retrospectively. The results were as follows: 1. Final diagnosis of 24 cases of pulmonary aspergillosis was aspergilloma in 16 cases, invasive aspergillosis in 2 cases, variant form of allergic bronchopulmonary aspergillosis in 3 cases, and endobroncnial aspergillosis in 3 cases. 2. The underlying causes of the aspergilloma were healed tuberculous cavity in 6 cases, bronchiectasis in 8 cases, and no underlying cause were found in 2 cases. All the 16 cases of aspergilloma were correctly diagnosed without difficultly by demonstrating the intracavitary mass or air meniscus. 3. Radiological findings of the invasive aspergillosis in kidney transplant patients were multiple round nodules with early cavitation and formation of aspergilloma which shows slowly progressive cavitation over 13 months in one case, and diffusely scattered miliary nodules with occasional cavitation in the other case. 4. Classic allergic bronchopulmonary aspergillosis were not found in our series but variant form of ABPA was found in 3 young female patients. AII the three patients shows some degree of central bronchiectasis and combined aspergilloma was found in 2 cases. 5. Three patients diagnosed as endobronchial aspergillosis-saprophytic infection of aspergillus in the bronchial tree-by bronchoscopic biopsy shows nonspecific radiological findings.

Percutaneous needle aspiration biopsy of localized pulmonary lesions

Over a period of recent two years, 100 patients who had localized pulmonary lesions and underwent percutaneousneedle aspiration and biopsy, were analized. There were 56 malignancies and 44 benign and 79% respectively.Differentiation of malignancy vs. benignity was possible in 89% of cases obviating unnecessary exploratorythoracotomy for diagnostic purpose, Five cases were misinterpreted and eight cases were non-diagnostic oncytology. Inadequate materail was obtained in two cases; one was due to hardness of the mass, which, later,confirmed as chondrosarcoma, and the other was too samll(0.8x1.0cm) to be visible on lateral view. Theobainenability of the tissue was 98%. 14(14%) patients developed pneumothorax; one of them required treatment andthe reminder showed spontaneous resporption. (Transient neglibigle blood tinged sputum was found in 16(16%)cases.) The method, problems and complications are discussed. Authors recommend the percutaneous needle aspirationand biopsy as the initial procedure in diagnostic work-up of pulmonary coin lesions, especially when they aresmaller, more peripheral and metastatic neoplasm is neoplasm is suspected.

Radiological differentiation of neurogenic tumors in the thorax with plain film and CT

35 neurogenic tumors of the thorax were analyzed with plain film and CT scan. Radiological analysis emphasizedshape, location calcification, bone change, pleural change in plain film and calcification, cystic change, bonechange, pleural change, presence of contrast enhancement in CT scan. The results were as follows; 1. Age may bethe most important clinical factor for differential diagnosis. 2. Plain film findings(35 cases); 1) The mostcommon shape in the ganglion series tumor (ganglioneuroma, ganglioneuroblastoma, neuroblastoma), was elongation(80%) and these tumors generally had tapered borders(50%). In contrast with those of the genglion series, nervesheath tumors(schwannoma, neurofibroma, malignant Schwannoma) showed a definite tendency to be roudn (95%) and thesulcus effect was more frequetnly seen(67.5%). Most of the masses were smooth. The lobulated masses were commonlymalignant ganglion series tumors. 2) Though overall incidence of calcification was low(8.6%), it was observed morefrequently in ganglion series tumors(20%). 3) Associated bony abnormality were generally observed in large tumorsabove 5cm in long axis, especially in neuroblastoma and ganglioneuroblastoma. 4) Tumors showed pleural effusionwere all malignant. 3. CT findings (17 cases); 1) The overall incidence of cystic change of the mass was 23.6%. Itwas most common in Schwannoma(60%). 2) The contrast enhancement was noted in 64.7%. It's degree was variable andshowed no predilection to any specific tumors. 3) The incidence of calcification, associated bony abnormality andpleural effusion were similiar to plain film. Confident specific diagnosis can be made in most of the neurogenictumors of the thorax by shape of the mass in plain film and internal architecture in CT combined with patient'sage as clinical information.

A study on microangiography of induced breast carcinoma in rats (I)

Microangiography is a very effective method in evaluating morphological changes of small vessels not onlybecause it shows subtle changes in microvasculature but also shows whole length of the vessels. Reccently many experimental studies on microagniography of normal and injured tissues are reported, but there's no report on microangiography of artificially induced cancer tissue. Authors artificially induced breast carinoma in rats withintravenous infusion of carcinogenic substance, N-methyl-N-Nitrosourea, and microangiography was done to evaluate vascularity and morphological changes of vessels of the cancer tissue. The results are as follows; 1.Distribtution of the tumor vessels showed tendency to form bolules. 2. Overall tumor vascularity was slightly hypervascular. 3. Variable sized, parallell arraged, tumor vessels surrounded the boundary of the lobules whilemore small vessels invaginated to the center of lobules in tortuous or straight fashion. 4. In overall, peripherayof the lobule was more vascular than center. 5. There was no evidence of cental tumor necrosis, and findings of extravasation of dye or venous lake formation were minimal. 6. Pathologically, the tumor tissue was well differentiated adenocarcinoma with tendency of lobule formation.

Posterior mediastinal teratoma

Teratomas, usually arising in the anerior mediastinum, are very uncommon in the posterior mediastinum. Embryologic development of anterior mediastinal teratoma is thought to be from thymic anlage which descends fromthe third branchial cleft and pouch, while that of posterior mediastinal teratoma is thought to be from the remnant of notochord. CT findings of posterior mediastinal teratomas are not different from teratomas elsewhere,containing fat, calcification, soft tissue and thick walled cyst. Ultrasonographic findings are mixed echogenicmass containing cystic portion, highly reflective solid portion and area of acoustic shadowing. Authors recently experienced 2 cases of surgically proven posterior mediastinal teratoma and report with review of literature.