Occult Papillary Thyroid Carcinoma Analysis: 214 Cases

PURPOSE: Occult papillary thyroid carcinomas (OPC) are defined as tumors measuring 0.5 cm in size. Therefore, we prefer near-total or total thyroidectomy with central lymph node dissection. Early detection and treatment of OPC might be warranted by the routine use of thyroid USG and USG-guided FNA.

Computer-Assited Instruction : MR Imaging of Congenital Heart Disease

PURPOSE: To develop a software program for computer-assisted instruction on MR imaging of congenital heart disease for medical students and residents to achieve repetitive and effective self-learning. MATERIALS AND METHODS: We used a film scanner(Scan Maker 35t) and IBM-PC(486 DX-2, 60 MHz) for acquisition and storage of image data. The accessories attached to the main processor were CD-ROM drive(Sony), sound card(Sound blaster-Pro), and speaker. We used software of Adobe Photoshop(v 3.0) and Paint Shop-Pro(v 3.0) for preprocessing image data, and Paint brush from Microsoft Windows 3.1 for labelling. The language used for programming was Visual basic(v 3.0)from Microsoft Corporation. RESULTS: We developed a software program for computer-assisted instruction on MR imaging of congenital heart disease as an effective educational tool.

Incidence of the Appearance of the Proximal Humeral Ossification Center of the Neonates and Infants on Plain Chest Radiograph

PURPOSE: To ascertain the incidence of proximal humeral epiphyseal ossification centers, as shown on chest radiographs, in neonates and infants. MATERIALS AND METHODS: The distribution of corrected age(CA) of the infantswas from 24 weeks of gestational age to 6 months of postnatal age. They were obtained from inborn and outborn infants without developmental problems. Proximal humeral epiphyseal ossification centers were evaluated by two radiologists from a total of 440 chest radiographs. Of these, 196 were of the female chest and 244 were of themale. Corrected ages based on postnatal age are expressed as weeks before two months of age and as months after two months of age. The ossified or nonossified epiphyses of the humeral heads were plotted against corrected age. From these graphs, the percentages of ossification according to their corrected age was observed. RESULTS: 37weeks of corrected age in which 9.1%(1/11) was ossified was the earliest age of humeral epiphyseal ossification in the female. While 35 weeks of CA in which 6.3%(1/16) was ossified was the earliest age in the male. In full-term neonates(=40 weeks of CA), 20%(6/30) of epiphysis was ossified in the female and 23.3%(7/30) in the male. The female group of 43-44 weeks of corrected age showed ossification of 50% and the male group of 44-45 weeks of corrected age showed ossification of 50%. By five months of corrected age, 100% of epiphyses, both in the female and in the male, were ossified. CONCLUSION: Humeral ossification centers are seen from 35-37 weeks of correctedage. By five months of age, all humeral epiphyses are ossified.

Primary Malignant Mesothelioma of the Pericardium: A Case Report

Primary malignant mesothelioma of the pericardium is a very rare and highly lethal neoplasm. Diagnosis is a difficult problem and most of the cases reported in the literature were diagnosed at postmortem. We report a caseof primary malignant mesothelioma of the pericardium in a 22 year-old man. CT and MR imaging both showed diffuse irregular pericardial thickening, soft tissue density with cystic lesion, nodular bulging into the myocardium, permeative growth of the tumor, and encasement of the heart and two great vessels.

Extra-Articular Synovial Chondromatosis: A case Report

A 60-year-old female presented with a slowly growing, painful mass in the superolateral portion of the rightt high. Physical examination, roentgenography, bone scan and magnetic resonance imaging revealed a soft tissue masswith mineralization which did not involve bone or joint. A triangular-shaped, mineralized lesion was found in the superior side of the greater trochanter on simple radiograph and on magnetic resonance imaging. It had not been detected clinically, and was asymptomatic. The masses were removed en bloc and diagnosed as extra articular osteochondroma. Eight months postoperatively, pain had almost been relieved.

A Comparative Study on Transcatheter Renal Arterial Embolization (TRAE) in Rabbits with Absolute Ethanol and Gelfoam Particles

PURPOSE: To evaluate the therapeutic effectiveness of absolute ethanol and gelfoam particles and the degree of vascular recanalization after gelfoam embolization. MATERIALS AND METHODS: Transcatheter renal arterial embolization(TRAE) was performal in 16 rabbits ; Eight were embolized with absolute ethanol, and eight with gelfoam particles. Of this total, three died less than one week after embolization. Pre- and post embolization angiographies at five minutes, one week, two weeks(gelfoam group only) and 5-6 weeks after embolization were performed. Six rabbits were sacrificed at one week, and seven at 5-6 weeks after embolization. Pathologic examination was performed. RESULTS: The ethanol group(n=6) showed complete occlusion of the main renal artery on follow-up angiography at one week and 5-6 weeks after embolization. The pathologic finding was complete total necrosis of embolized kidneys. The gelfoam group(n=7) showed partial recanalization of renal arteries in follow upangiography at one week, two weeks and 5-6 weeks after embolization. The pathologic finding was partial lysis ofgelfoam particles within intrarenal arteries. CONCLUSION: Absolute ethanol can be used as a permanent embolicagent and gelfoam as a temporary such agent in various clinical applications. Gelfoam, however, did not show complete recanalization on angiography and pathology at six weeks after embolization.

CT and MR Imaging in Staging Non-Small Cell Bronchogenic Carcinoma

PURPOSE: To evaluate accuracy of magnetic resonance(MR) imaging for staging of lung cancer and to compare the accuracies of CT and MRI. MATERIALS AND METHODS: We retrospectively analyzed 25 cases of lung cancer, which were confirmed surgically and pathologically. Five experienced radiologists participated in the receiver operating characteristic (ROC) analysis to evaluate and compare accuracies of the CT and MR imaging in preoperative staging of non small cell lung cancer by assessing tumor invasion of bronchus, mediastinum, chest wall, and hilar or mediastinal lymph node metastasis. Imaging results were evaluated against "truth" data based on both surgery and pathologic examination. RESULTS: Sensitivity of CT in distinguishing T3-T4 tumors was 60% ;specificity was 76%. These values for MR imaging were not significantly different(53% and 72%). With ROC analysis, no difference existed between accuracies of CT and MR imaging in diagnosis of bronchial involvement, but MR imaging was significantly more accurate than CT(p<0.05) in diagnosis of mediastinal invasion. There was no significant difference between accuracies of CT and MR imaging in detecting mediastinal node metastasis(N2 or N3); sensitivities were 64% and 78%, respectively, and specificities were 64% and 66%. CONCLUSION: There was no significant difference in accuracies of CT and MR imaging in preoperative tumor classification and assessment of mediastinal node metastasis, but MR imaging was more accurate than CT in assessment of mediastinal invasion.

CT and MR Imaging in Staging Non-Small Cell Bronchogenic Carcinoma

PURPOSE: To evaluate accuracy of magnetic resonance(MR) imaging for staging of lung cancer and to compare the accuracies of CT and MRI. MATERIALS AND METHODS: We retrospectively analyzed 25 cases of lung cancer, which were confirmed surgically and pathologically. Five experienced radiologists participated in the receiver operating characteristic (ROC) analysis to evaluate and compare accuracies of the CT and MR imaging in preoperative staging of non small cell lung cancer by assessing tumor invasion of bronchus, mediastinum, chest wall, and hilar or mediastinal lymph node metastasis. Imaging results were evaluated against "truth" data based on both surgery and pathologic examination. RESULTS: Sensitivity of CT in distinguishing T3-T4 tumors was 60% ;specificity was 76%. These values for MR imaging were not significantly different(53% and 72%). With ROC analysis, no difference existed between accuracies of CT and MR imaging in diagnosis of bronchial involvement, but MR imaging was significantly more accurate than CT(p<0.05) in diagnosis of mediastinal invasion. There was no significant difference between accuracies of CT and MR imaging in detecting mediastinal node metastasis(N2 or N3); sensitivities were 64% and 78%, respectively, and specificities were 64% and 66%. CONCLUSION: There was no significant difference in accuracies of CT and MR imaging in preoperative tumor classification and assessment of mediastinal node metastasis, but MR imaging was more accurate than CT in assessment of mediastinal invasion.

Mediastinal lymph node enlargement on CT scans in idiopathic pulmonary fibrosis

The increase in size of lymph node on Ct scan is the single most important finding of lymphadenopathy. The purpose of this study was to evaluate the size of mediastinal lymph nodes in patients with idiopathic pulmonary fibrosis with no evidence of malignancy or current infection. CT scans of 70 patients (16 with conventional CT and 54 with high-resolution CT) were assessed for lymph node size and locations. The duration of symptoms, and the extent and patterns of the parenchymal lung disease on CT scans were correlated with lymph node enlargement. In 54 of 70 patients, more than one lymph nodes were larger than 1-1.5cm. The prevalence of mnode enlargement increased significantly with a longer duration of symptom (p=0.001), larger extent of the disease (p=0.043), and with a greater proportion of honeycomb pattern (p=0.0344). Right paratracheal, subcarinal, right tracheobronchial, and paraesophageal nodes were the most common sites of nodes enlargement. In conclusion, mediastinal lymph node enlargement is common in patients with idiopathic pulmonary fibrosis and is more frequently seen in patients with a longer duration of clinical symptoms, greater extent of the disease, and with a larger proportion of honeycomb pattern.

Ultrasonography and arthrography in rotator cuff lesions: algorithmic approach

Twenty-six patients with chief complaint of shoulder pain who underwent both ultrasonographic examination and arthrography of the shoulder were analyzed. Ten out of 12 cases with clinical impression of frozen shoulder, showed normal findings on the ultrasonographic examination of the shoulder. Among these ten cases, nine cases showed abhesive capsulitis and one case showed rotator cuff tear on arthrography. Among six cases with the clinical impression of rotator cuff tear, five cases showed rotator cuff tear and one case showed combined calcific tendinitis and adhesive capsulitis on ultrasonographic examination. In arthrography, four cases of rotator cuff tear, one case of calcific tendinitis and biceps tendinitis and one case of normal findings were diagnosed. For the remaining eight cases in the ultrasonographic examination, normal finding or biceps tendinitis were found and for the remaning of the cases in arthrography adhesive capsulitis were found. With the above results, we recommend that the shoulder ultrasonography as the first line diagnostic modality for a patients with chief complaint of shoulder pain.

Lymphangiomas in children: correlation of sonographic and pathologic findings

The sonographic features of 23 lymphangiomas (19 pediatric patients) were compared with the pathologic findings. Nineteen lymphangiomas appesred as unicameral (n=2) and multiloculated (n=7) cystic masses. Remaining lesions were inhomogeneously echogenic mass with small cystic portions (n=3) and a mixed pattern (n=1). Fourteen of the multiloculated tumors had thin septa and 6 had solid echogenic foci. The fluid within the majority of the cyst was anechoic in 8 cases and echogenic in 11 cases. Correlation of the sonographic features with the pathologic findings demonstrated that the cystic spaces corresponded to the dilated lymphatic spaces lined with endothelium, separated by septa. Echogenic fluid represented hemorrhage. The echogenic component corres ponded to clusters of very smaller dilated lymphatic channels, thick fibro-fatty septa, or blood clot. The author's experience suggests that the most characteristic sonographic appearance of lymphangioma is a multiloculated cysti mass with thin septa, reflecting the preponderance of fluid-filled spaces. An atypical appearance usually reflects the presence of blood or dominancy of cavernous type. The information obtained with US imaging can help in providing a preoperative diagnosis and in planning surgical resection.

Too many ducts sign: a characteristic cholangiographic finding of clonorchiasis?

Clonorchiasis procucts diffuse dilatation of the small and medium sized intrahepatic bile ducts and its cholangiogram shows visualization of many bile ducts, especially, tertiary, quaternary, and more peripheral tributaries up to the 6th tributaries. In an attempt to clarify this cholangiographic sign quantitively, we counted the visualized smaller bile ducts in clonorchiasis and compared the number of visualized ducts in normal cholangiogram, recurrent pyogenic chlangitis and carcinoma of the extrahepatic ducts. In clonorchiasis the number of visualized smaller bile ducts was considerably geater than in normal subjects and recurrent pyogenic cholangitis, but there was no singnificant statistical differences in the number of visualized bile duct tributaries between clonorchiasis and carcinoma of the bile ducts. Thus it is considered that too many ducts sign is not a unique cholangiographic finding of clonorchiasis, but we believe that in the presence of this sign with other we l known cholangiographic findings, diagnosis of clonorchiasis is very easy.

Balloon dilatation of the esophageal strictures in infants and children

Balloon dilatation has been applied in treatint of various pathologic narrowing of the hollow viscus. It is now accepted as very effective modality especially in treating esophageal stenosis obviating surgical procedure. We performed 128 balloon dilatations in 29 patients with the number of dilatations in each patient ranging from once to 12 times. The age distribution of the patients was from 3 weeks to 6 years, with the median age of 3 months. Twenty nine patients consisted of 25 postoperative esophageal strictures (21 esophageal atresia with tracheoesophageal fistula, 1 congenital esophageal stenosis, 2 tracheobronchial remnant, and 1 congenital esophageal stenosis with esophageal atresia), 2 achalasia, 1 congenital esophageal stenosis, and 1 corrosive esophagitis. We had successful dilation in 22 patients, who showed subsequent relief of symptoms and improvement in the diameter of stenotic segment. In 4 patients, esophageal perforation occurred during the procedure, one requiring emergency thoracotomy and the other threeconservative management. Seven patients had no improvement in stenotic sites after several balloon dilatations. Failed cases were congenital stenosis, achalasia, corrosive esophagitis and four postoperative strictures. We believe that balloon dilatation is the procedure of choice in the treatment of postoperative esophageal stricture in infants and children and is a safe method as the perforation which can complicate the procedure could be managed conservatively.

Hepatic undifferentiated embryonal sarcoma in children

Undifferentiated embryonal sarcoma(UES) is an uncommon malignant hepatic tumor that occurs in older children and young adults. Six cases of UES were reviewed to determine their characterisfic findings on sonography (US) (n=5), computed tomography (CT) (n=6), and angiography (n=2) US demonstrated a single large, echogenic mass with some anechoic spaces in each case. CT revealed a well demarcated hypodense mass with hyperdense septa of variable shape and thickness. Four cases showed enhancing peripheral rim and some solid portions at the periphery or adjacent to the septa. Follow-up CT scan in one case who had not been treated showed enhancing solid portion changed to hypodense areas. Angiography showed hypovascular or avascular mass. Familiarity with these radiological findings of UES of liver will be helpful in differential diagnosis of primary hepatic tumors of childhood.

Intracranial teratoma in childhood: MRI findings

We reviewed the magnetic resonance imaging (MRI) of intracranial teratoma to detect the characteristic findings. Five patients with intracranial teratoma were evaluated with MRI from January 1988 to December 1990. Four male and one female patients with age ranging from 6 to 14 years were surgicelly confirmed MRI was done with 2.0T superconducting system(Spectro 20000, Goldstar, Seoul) and gadolinium enhancement was done in 4 patients. We retrospectively reviewed the clinical, operative, pathologic, and radiologic findings. Intracranial teratomas showed fatty component, calcification and cystic component filled with sebum or serous fluid. Peripheral rim enhancement was seen in three and irregular enhancement in two cases. There were hydrocephalus in all teratoma, but neither surrounding edema nor surrounding tissue invasion was seen. Low signal intensity rim was noted around the solid component of all tumors and they were not enhanced. MRI showed multicomponent of intracranial teratoma including the solid and cystic component, and low singal rim which might be the characteristic findings of the intracranial teratoma.

Diagnostic value of computed tomography in pancreatic cancer

This retrospective study was performed to assess CT scan findings of pancratic cancer and its ability todetermine resectability. CT scans of 41 patients, who were diagnosed to have pancreatic cancer on histological orclinical base, were reviewed. Most common findings were; focal pancreatic enlargement, diffuse pancreaticenlargement, loss of distinct contour, peripancretic fat obliteration, bile duct or pancreatic duct dilatation,vascular invasion, lymph node involvement, direct invasion of adjacent organs and distant metastasis.Resectability was assessed according to generally accepted CT findings such as small pancreatic mass lesion havingnormal lobulated contour of pancreas, no evidence of vascular invasion, no evidence lymph node involvement andfree of distant metastasis. With the criteria, 5 cases among 41 cases deemed to be resectable. However onoperation all cases were found unresectable indicating prediction of tumor resectability is difficult even withhelp of CT. Nonetheless CT would be very helpful in management of patients having pancreatic cancer since CT wouldshorten the diagnostic procedures of pancreatic cancer.