Intracapsular and Paraarticular Chondroma of the Infrapatellar Hoffa's Fat Pad: A Case Report

Intracapsular and paraarticular chondroma is a rare benign lesion of the large joints (mostly the knee). We report a case of intracapsular and paraarticular chondroma in the infrapatellar Hoffa's fat pad that presented as a painful palpable mass in 15-yearold woman. A physical examination revealed a firm, movable and tender mass in the infrapatellar area. Magnetic resonance images showed an ovoid, well-defined, soft tissue mass with focal calcification in the infrapatellar fat pad. The final pathology revealed an intracapsular and paraarticular chondroma.

Primary Mucosa-Associated Lymphoid Tissue Lymphoma of the Breast: A Case Report

A primary mucosa-associated lymphoid tissue lymphoma (MALT lymphoma) of the breast is extremely rare. We report a case of a MALT lymphoma of the breast that presented as a palpable left breast mass in a 37-year-old woman. A physical examination revealed a large firm, and fixed mass in the left inner breast. Mammograms showed a large, isodense mass in the lower inner quadrant of the left breast and an enlarged lymph node in the axilla. A sonogram demonstrated a 5 cm sized, oval, circumscribed, and heterogeneously hypoechoic mass with posterior acoustic enhancement. A surgical biopsy was performed, and the pathology revealed a MALT lymphoma.

Primary Malignant Fibrous Histiocytoma of the Mesentery: A Case Report

A malignant fibrous histiocytoma of the mesentery is rare, and multifocal involvement as a primary tumor is very rare. In this report, a case of malignant fibrous histiocytoma of the mesentery presenting with two masses and multiple peritoneal seeding in a 48-year-old man is described. A physical examination revealed a large, firm, and non-tender mass in the right lower abdomen of the patient. Computed tomography of the lesion revealed a partially, indistinctly marginated and heterogeneously enhancing mass with irregular peritumoral strands in the mesentery of the right lower abdomen, while sonograms of the lesion revealed an ill-defined low-echoic mass. The final pathology demonstrated the presence of a storiform-pleomorphic malignant fibrous histiocytoma.

Peripheral Cholangiocarcinoma: Radiologic Significance of Hypoechoic Halo Sign on Sonography

PURPOSE: To determine the prevalence and characteristics of the hypoechoic halo sign in peripheral cholangiocarcinoma. MATERIALS AND METHODS: Seventeen sonograms of 17 patients with peripheral cholangiocarcinoma histologically proven by either percutaneous needle biopsy (n=16) or surgical biopsy (n=1) were retrospectively reviewed. The size, margin, homogeneity and internal echogenicity of the masses as well as their peritumoral ductal dilatation and intratumoral calcification were ascertained, and the presence of a hypoechoic halo, and if present, its thickness and type, were also determined. We arbitrarily defined a 'thin' and 'thick' halo respectively, as one with a thickness less than of less than 3 mm, and 3 mm or more, and classified halos as 'intratumoral', 'extratumoral', or 'mixed'. RESULTS: Tumor diameter ranged from 4 to 13.5 (mean, 7.3) cm, and the margin was well-defined in 15 cases (smooth: n=2; lobulated: n=13) and irregular in two. Echogenicity was slightly heterogeneous in 11 cases, severely heterogeneous in three, and homogeneous in three, while the central portion was hyperechoic in eight cases, isoechoic in seven, and hypoechoic in only two. A hypoechoic halo was detected in 10 of 15 tumors(67%) with isoechoic centers. In evaluating the halo, two cases in which the mass was hypoechoic were excluded. All ten hypoechoic halos were at least 3 (range, 4-13; mean, 8.3) mm thick; in two cases the presence of a halo was equivocal, and in three there was no halo. Eight of ten halos were the mixed type, two were intratumoral, and none were extratumoral. Peritumoral ductal dilatation was seen in four cases (24%), but no internal calcification was observed. CONCLUSION: US showed that the margins of peripheral cholangiocarcinomas were mostly well-defined and smooth (12%) or lobulated (76%), and that masses were mainly heterogeneous (64%). A hypoechoic halo, which in all cases was thick and in 80% of cases was mixed, was noted in 67% of tumors with a hyper (47%) or isoechoic (41%) center. A halo of this kind may be useful in isoechoic mass detection and also in the differentiation of hyperechoic peripheral cholangiocarcinoma from hepatic hemangioma, the most common hyperechoic benign tumor.

Malignant Ectomesenchymoma in a Two-Month-Old Boy

Malignant ectomesenchymoma is a rare tumor originating from remnants of migratory neural crest(ectomesenchyme) and composed of neuroectodermal as well as mesenchymal components. Neuroblasts and ganglion cells constitute the neuroectodermal components and rhabdomyosarcoma is the most frequently encountered mesenchymal components. We report a case of malignant ectomesenchymoma in a two-month-old boy who was presented with abdominal pain and urinary difficulty. The tumor appeared to arise from the prostatic region and enlarged to compress the bladder leading to bilateral hydronephrosis. Immunohistochemical studies for the resected tumor confirmed the presence of mixed ganglioneuroma and rhabdomyosarcoma establishing the diagnosis of malignant ectomesenchymoma. However, in the initial biopsy specimen of tumor, poorly differentiated round to oval cells positive for both desmin and vimentin staining were uniformly noted and the incorrect diagnosis of rhabdomyosarcoma was made. Intensive multi-agents chemotherapy, surgery and radiotherapy had failed in preventing the development of local recurrences. Subsequently, invasion of pubic bone and lung metastases ensued. This report enlightens the need for immunohistochemistry to seek possible neuroectodermal components in a tumor specimen suggestive of rhabdomyosarcoma.

MR Findings of Transient Synovitis of the Hip

PURPOSE: To evaluate the MR findings of transient synovitis of the hip in children. MATERIALS AND METHODS: Between 1993 and 1997, MR imaging was performed in 30 children(male:female=22:8) in whom transient synovitis had been clinically diagnosed. In 20 of these 30 patients, Gd-en-hanced study was also performed. The signal intensity of bone marrow of the femur, the synovial enhancement pattern and the amount of hip joint effusion in affected hips were evaluated; the last-mentioned was determined using the volume measurement method. RESULTS: In 29 patients(97 %), no abnormal signal intensity was seen in bone marrow of the femur in affected hips. Gd-enhanced MR imaging revealed synovial enhancement of affected hip joints, as follows: minimal en-hancement in eight patients(40 %), moderate enhancement in eight(40 %), and strong enhancement in four( 20%). No abnormal enhancement was demonstrated in bone marrow of the femur or adjacent soft tissue. The mean amount of joint effusion of affected hips was 2.7 +/- 1.7(range, 0.2 -18.9)ml; statistically, this was much greater than that of contralateral hip (p<0.01). CONCLUSION: The MR findings of transient synovitis of the hip in children were normal bone marrow signal intensity of the femoral head, moderate or strong synovial enhancement, and asymmetric hip joint effusion.

Radiologic Findings of Submucosal Tumors of Gastrointestinal Tract

Gastrointestinal submucosal tumors originate from submucosal histologic structures such as muscles, lymph nodes, nerves, fibers and vessels. Most patients are asymptomatic. Lesions that are large or ulcerated may cause abdominal pain or upper gastrointestinal bleeding, and those that grow intraluminally sometimes become pedunculated and occasionally prolapse to cause intussusception. Adenocarcinoma is the most common primary gastrointestinal tumor, accounting for approximately 90-9 5 % of such lesions, while submucosal tumors account for approximately 2 -6% of all gastrointestinal tumors. Because their overlying mucosa appears normal, submucosal tumors age after difficult to visualize endo-scopically, and for this reason, barium studies or CT scans are helpful for diagnosis. In this paper, variable CT and barium study findings of the different types of gastrointestinal submucosal tumor are demonstrated, and a brief discussion of the respective disease entities is included.

Management of Advanced Hilar Biliary Malignancy with X-shaped Stenting Technique

PURPOSE: To report X-shaped stent insertion and its result in the patients with advanced hilar malignancy. MATERIALS AND METHODS:X-shaped stents were inserted in six patients with advanced hilar malignancy involving segmental branches of both intrahepatic bile ducts (IHD). The causes were cholangiocarcinomas in five patients and recurrent GB cancer in one. The procedure includes three steps: 1) the insertion of two wires through three IHDs in an X configuration, using a stone basket; 2) balloon dilatation of lesions, and 3) the in-sertion of two stents in an as X configuration. Stents were inserted after balloon dilatation in five patients, and without balloon dilatation in one. Changes in serum bilirubin levels and procedure-related problems were reviewed. RESULTS: In all patients, serum bilirubin levels gradually decreased, but in two, they increased again. One of these two died of sepsis after 1 month. There was bile leakage through the puncture and bile was extracted from malignant ascites. In the other patient, occlusion of the left stent tip occurred, and additional left PTBD was performed 3 months later. Hemobilia developed in all five patients with balloon dilatation, these all experianced pain during dilatation , but afterwards this disappeared. One stent without pre-balloon dilation showed incomplete self-expansion at the crossing part and supplementary balloon dilatations were performed. CONCLUSION: In patients with advanced hilar malignancy, X-shaped stent insertion is a new palliation. Problems such as hemobilia, pain, and intraperitoneal bile leakage may, however, occur.

Experience of septic shock after percutaneous management of obstructed afferent loop with obstructive jaundice: 3 cases report

Percutaneous transhepatico-biliary duodenal drainage(PTBDD) (n=2) and percutaneous transhepatic duodenaldrainage(PTDD) (n=1) were performed as palliative treatment of obstructed afferent loop in patients in whomobstructive jaundice had occurred after surgery for malignant tumors. All three patients experienced septic shockafter PTBDD or PTDD. We describe these cases and review the literature.

A Classification System of the Extent of Femoral Head Osteonecrosis Using MRI / 대한정형외과학회잡지

We tested the hypothesis that the extent of necrosis at the initial MRI predicts the subsequent risk of collapse of the femoral head in a randomized clinical trial conducted to compare the core decompression to the conservative treatment. After the initial clinical evaluation including plain roentgenography and MRI, 37 hips of early-stage osteonecrosis (ON) in 33 patients were randomly assigned to core decompression group or conservative treatment group. All the patients were regularly followed by clinical evaluation including plain roentgenography and MRI at three-month intervals. The extent of ON was estimated on the basis of the percentage of abnormal signal intensity in the weight-bearing portion of the femoral head as determined on a combination in coronal aod sagittal MR images. The angle of necrotic portion in mid-coronal image (A) and that in mid-sagittal image (B) were used to quantify the extent of necrotic portion by the formula; (A/180) x (B/180) x 100%. A strong association was observed between the percentage of necrotic portion and the development of collapse. We concluded that the extent of necrotic portion is a major risk factor of the collapse and proposed a systematic method of classifying the percentage of necrotic portion, which might be useful as a predictive index for the fate of early-stage ON.

Peripheral Cholangiocarcinoma: Contrast Enhancement Characteristics on Spiral CT

PURPOSE: To evaluate the characteristics of contrast enhancement of peripheral cholangiocarcinoma, as seen on spiral CT. MATERIALS AND METHODS: Spiral CT was used to examine twelve patients with peripheral cholangiocarcinoma of the liver. All underwent conventional CT before contrast enhancement. After the administration of contrast material, two-phased spiral CT was used to investigate seven patients, and three-phased spiral CT, to investigate five. In each phase, we analysed the patterns of contrast enhancement at the central and peripheral portions of the lesion, and compared these with the patterns of normal liver parenchyma. We evaluated changes, according to time lapse, in the central low-density area, and obtained the phase-density curve with the cursor placed at the central portion of the lesion. For three-phased spiral CT examinations, we also tried to determine the phase dvring which the margin of the lesion was most clearly demonstrated. RESULTS: During the arterial phase, eight of twelve patients (67%) showed hyperdensity in the peripheral portion of the lesion; during the portal phase, four of five patients (80%) showed hypodensity in both the central and peripheral portions. During the delayed phase, six of twelve patients (50%) showed isodensity and five showed high density in the peripheral portion. Compared to those in the arterial phase, central hypodense areas relative to normal liver parenchyma in the delayed phase decreased in eleven of twelve patients (92%). On phase-density curves, the density of the central portion of the lesion increased progressively in nine of twelve patients (75%). On three-phased CT, the margin of lesion was-in all five patients - most clearly demonstrated in the portal phase. CONCLUSION: On spiral CT, the central portion of peripheral cholangiocarcinoma always showed low density and the peripheral portion showed high, low, or iso or high density, depending on the phase. In addition, spiral CT clearly demonstrated a minimal centripetal pattern of contrast enhancement. We therefore conclude that in the diagnosis of peripheral cholangiocarcinoma, the characteristics of contrast enhancement are helpful.

Significance of CT Severity Index in Acute Pancreatitis

PURPOSE: To assess the usefulness of a CT severity index(CTSI) for the evaluation of acute pancreatitis and to correlate it with clinical findings. MATERIALS AND METHODS: We retrospectively evaluated contrast enhanced CT in 34 patients with acute pancreatitis. They were categorized into low-score(0-2), middle-score(3-6), and high-score(7-10) groups according to CTSI points, and those groups were correlated with duration of fasting period, days in hospital morbidity and mortality. We attempted to determine the differences in CTSI between pancreatitis caused by alcohol and by biliary tract disease. RESULTS: Of 34 patients, 11 were placed in the low-score group, 19 in the middle-score group, and 4 in the high-score group. The patients in the middle-score group experienced longer fasting period and stayed longer in hospital than those in the low-score group(p<.05 and p=.08, respectively). Morbidity was 0% in the low-score group, 37% in the middle-score group and 50% in the high-score group. Mortality occurred in two patients in high-score group, only. Alcohol-induced pancreatitis generally showed a higher CTSI and more severe clinical course than pancreatitis caused by biliary tract disease. CONCLUSION: In the evaluation of acute pancreatitis, CTSI can be a useful predictor of its prognosis.

CT Findings of Mucinous Adenocarcinoma in Gastrointestinal Tract

PURPOSE: To evaluate CT findings of mucinous adenocarcinoma in the gastrointestinal tract. MATERIALS AND METHODS : CT scans of 24 gastric and five colorectal mucinous adenocarcinomas, proven by histology, were retrospectively analysed; the patients consisted of 18 men and 11 women (age range, 27-76; mean, 59). CT findings were analysed, with emphasis on : (a) tumor size and maximal wall thickness ; (b) the presence of a low attenuation area, suggestive of a mucin poll within the tumor ; (c) the presence, shape and location of calcification, and (d) correlation between primary tumor (T) staging and CT findings. RESULTS: The mean tumorsize of gastric mucinous adenocarcinoma was 8.2cm (range, 1.4 - 17cm) and the mean maximal wall thickness was2.3cm (range, 1-4.5cm). Low attenuation areas on enhanced CT were seen in 12 cases (50%). Mottled, punctate, diffuse calcifications were demonstrated in nine cases(38%), and were located in low attenuation areas in eight cases. The T staging could be determined in 22 cases. Of there, low attenuation areas were demonstrated in tencases and calcification in seven. Of those ten cases with low atteuation area T staging was T2 in two cases, T3 intwo, and T4 in six. Of the cases showing calcification, T staging was T3 in one case and T4 in six. The mean sizeof colorectal mucinous adenocarcinoma was 6cm(range, 3-13cm) and the mean maximal wall thickness was 3.6cm (range,1.5-7cm). Low attenuation area were seen in three cases. Mottled calcification within the low sttenuation was detected in one case. The T staging of three cases which showed a low attenuation area was T3 in tow cases and T4in one case. One case with calcification was T3 stage. CONCLUSION: The CT finding of mucinous adenocarcinoma inthe gastrointestinal tract was a relatively thick-walled mass containing an area of low attenuation or calcification. Although calcification is believed to be a pathognomonic finding for the specific diagnosis of mucinous adenocarcinoma, a low attenuation area may be an important CT finding because it can be detected at lower T staging and more frequently.

CT Measurement of Wall Thickness of Early Gastric Cancer: Correlation with Upper GI Series

PURPOSE: The purpose of this study is to determine the detection rate of early gastric cancer and to measure the focal gastric wall thickening in computed tomography. MATERIALS AND METHODS: From November 1991 to November 1993, 19 patients (age;33--76 years, male ;female:4;5) with surgically proven early gastric cancer were examined by upper gastrointestinal series and abdominal computed tomography. Twenty lesions in these patients were included in this study. Computed tomography was performed with conventional technique using gastrografinR (17 cases) or water filling (2 cases) method in supine position. Additional scans were obtained either in right down decubitus (15 cases) or supine position (4 cases) with an ingestion of gas forming agent. We determined the detection rate of early gastric cancer at computed tomography and measured the maximum thickness of the lesion. RESULTS: The pathologic types of the early gastric cancer were type lib + IIc in 5 cases, type IIc in 6, type III in 3 and type I, I + IIc, Ila, lib, lib + III and IIc + III in one, respectively. Seventy-five percent (15 cases) of early gastric cancer was detected at upper gastrointestinal series and fifty percent (10 cases) at computed tomography. Computed tomography could detect 100% of elevated carcinomas (3/3) and 41% of depressed carcinomas (7/17). The maximum thickness of the lesion ranged from 7 mm to 11 mm (mean ;8mm). CONCLUSION: In a well-distended stomach, CT could detect focal gastric wall thickening (mostly, less than 1 cm) caused by early gastric cancer in half of the cases.

CT Analysis of Intratumoral Gas Formation after Hepatic Tumor Embolization

PURPOSE: To evaluate the prevalence and the patterns of sterile gas shown at computed tomography(CT) after transarterial embolization(TAE) for primary hepatic tumor. MATERIALS AND METHODS: Among 102 patients who performed TAE for hepatoma, thirty-four in whom follow-up CTwas underwent constituted the basis of our study. At CT, we evaluated the patterns and locations of intratumoral gas. We also reviewed the clinical data to exclude an infectious origin of intratumoral gas. RESULTS: Of 34 patients, intratumoral gas was detected in 11 patients(32%), in all of whom Gelfoam was used as an embolic material. The initial tumor size measured at pre-TAE CT was larger in patients with intratumoral gas than in patients without it(p < 0.005). No specific patterns or locations of intratumoral gas were noted on CT scans. No patients had clinical signs and symptoms that suggested infection. CONCLUSION: Intratumoral gas formation without clinical evidence of infection is not an infrequent finding after TAE for hepatoma, especially when Gelfoam is used and when the tumor is large in size. This finding may be a part of postinfarction syndrome and should not be misinterpreted as an postprocedural abscess formation.

Non-Hodgkin Lymphoma Containing Low Attenuation Area at Enhanced CT: Correlation with Histopathologic Typing

PURPOSE: To evaluate the frequently of low ahetenuation area in enhanced CT scans of non-Hodgkin lymphoma(NHL) and to find out if there is any pertinent relationship between this and the histopathologic classification. MATERIALS & METHODS: The authors reviewed CT scans in the newly diagnosed 53 patients with NHL. We defined the-low attenuation area as the one with CT attenuation value lower than that of the muscle, surrounding lesion, or other lymph nodes after contrast enhancement. NHL with the low attenuation areas were correlated with the histopathologic findings according to the classification based on the Working Formulation and the frequency of the lesion was evaluated. RESULT: Of the 53 patients, the low attenuation area was found in 13 patients (25%) at CT. The histopathologic classification could be made in 12 patients, among whom one patient was classified as low grade, six as intermediate grade, and five as high-grade. Concerning the specific cell typing, the diffuse large cell type was most common in intermediate-grade NHL seen in five patients and the large cell, immunoblastic type was most common in high-grade NHL seen ih three patients. CONCLUSION: The authors concluded that the low attenution area within lymphoma is not an infrequent finding at CT, and there was no stastistically significant correlation between this finding and the prognostic grading of the Working Formulation.

Percutaneous Catheter Drainage of Liver Abscess: Clinical Outcome

PURPOSE: We studied to evaluate the effect of percutaneous catheter drainage (PCD) in liver abscess. MATERIALS AND METHODS: We retrospectively analyzed clinical data (presence of fever, WBC count), radiological findings (computed tomography, ultrasonography and abscessogram) and correlated them with treatment period. Percutaneous drainage of liver abscess were performed in 19 patients under fluoroscopy guide during recent three years. RESULTS: Eighteen patients (95%) were cured, and one patient underwent surgery because of peritonitis caused by PCD procedure. Average treatment period was 17 days. CONCLUSION: In the treatment of liver abscess, PCD is thought to be safe and effective.

Epithelioid Hemangioendothelioma of the Liver: A Case Report

Hepatic epithelioid hemangioendothelioma is a rare tumor of vascular origin having a intermediate clinical course between benign cavernous hemangioma and malignant anglosarcoma. Patients present nonspecific clinical signs and symptomas. We experienced a case of surgically proven hepatic epithelioid hemangioen-dothelioma. Computed tomography showed multiple nodules with internal calcifications, chiefly in peripheral portion of both lobes of the liver. Ultrasonography showed hypoechoic nodules and tiny calcific foci in peripheral portion. Open biopsy of the liver and the omenrum confirmed epithelioid hemangioendotheliomas.

Severe aseptic meningitis with hydrocephalus following introlan myelography: a case report

A case of severe aseptic meningitis with communicating hydrocephalus following iotrolan myelography is presented. The patient's condition improved very quickly after corticosteroid therapy. Rapid improvement and absence of pathogenic organisms in the CSF culture strongly favor an aseptic meningitis. This is the first reported case of aseptic meningtis with the secondary development of hydrocephalus caused by iotrolan myelography.

Severe aseptic meningitis with hydrocephalus following introlan myelography: a case report

A case of severe aseptic meningitis with communicating hydrocephalus following iotrolan myelography is presented. The patient's condition improved very quickly after corticosteroid therapy. Rapid improvement and absence of pathogenic organisms in the CSF culture strongly favor an aseptic meningitis. This is the first reported case of aseptic meningtis with the secondary development of hydrocephalus caused by iotrolan myelography.