Late-Onset Postpneumonectomy Empyema Presenting as Right-Sided Heart Failure: Extrinsic Right Atrial Compression

Although it is rare, the right atrium can be encroached on by abnormal mediastinal structures, including aortic aneurysms, carcinomas, hepatic cysts and diaphragmatic paralysis. Extrinsic compression of the right atrium causes significant hemodynamic compromise and can lead to fatal outcomes. We describe the case of a 66-year old man with a past history of pulmonary tuberculosis that had undergone right pneumonectomy 40 years previously. He then presented with signs and symptoms of right-sided heart failure. These new signs and symptoms were recognized to be secondary to extrinsic compression of the right atrium, which was due to late-onset postpneumonectomy empyema, and the signs and symptoms were successfully relieved by performing open drainage of the empyema.

Detection of Hepatic Lesion: Comparison of Free-Breathing and Respiratory-Triggered Diffusion-Weighted MR imaging on 1.5-T MR system

PURPOSE: To compare free-breathing and respiratory-triggered diffusion-weighted imaging on 1.5-T MR system in the detection of hepatic lesions. MATERIALS AND METHODS: This single-institution study was approved by our institutional review board. Forty-seven patients (mean 57.9 year; M:F = 25:22) underwent hepatic MR imaging on 1.5-T MR system using both free-breathing and respiratory-triggered diffusion-weighted imaging (DWI) at a single examination. Two radiologists retrospectively reviewed respiratory-triggered and free-breathing sets (B50, B400, B800 diffusion weighted images and ADC map) in random order with a time interval of 2 weeks. Liver SNR and lesion-to-liver CNR of DWI were calculated measuring ROI. RESULTS: Total of 62 lesions (53 benign, 9 malignant) that included 32 cysts, 13 hemangiomas, 7 hepatocellular carcinomas (HCCs), 5 eosinophilic infiltration, 2 metastases, 1 eosinophilic abscess, focal nodular hyperplasia, and pseudolipoma of Glisson's capsule were reviewed by two reviewers. Though not reaching statistical significance, the overall lesion sensitivities were increased in respiratory-triggered DWI [reviewer1: reviewer2, 47/62(75.81%):45/62(72.58%)] than free-breathing DWI [44/62(70.97%):41/62(66.13%)]. Especially for smaller than 1 cm hepatic lesions, sensitivity of respiratory-triggered DWI [24/30(80%):21/30(70%)] was superior to free-breathing DWI [17/30(56.7%):15/30(50%)]. The diagnostic accuracy measuring the area under the ROC curve (Az value) of free-breathing and respiratory-triggered DWI was not statistically different. Liver SNR and lesion-to-liver CNR of respiratorytriggered DWI (87.6+/-41.4, 41.2+/-62.5) were higher than free-breathing DWI (38.8+/-13.6, 24.8+/-36.8) (p value <0.001, respectively). CONCLUSION: Respiratory-triggered diffusion-weighted MR imaging seemed to be better than free-breathing diffusion-weighted MR imaging on 1.5-T MR system for the detection of smaller than 1 cm lesions by providing high SNR and CNR.

Detection of Hepatic Lesion: Comparison of Free-Breathing and Respiratory-Triggered Diffusion-Weighted MR imaging on 1.5-T MR system

PURPOSE: To compare free-breathing and respiratory-triggered diffusion-weighted imaging on 1.5-T MR system in the detection of hepatic lesions. MATERIALS AND METHODS: This single-institution study was approved by our institutional review board. Forty-seven patients (mean 57.9 year; M:F = 25:22) underwent hepatic MR imaging on 1.5-T MR system using both free-breathing and respiratory-triggered diffusion-weighted imaging (DWI) at a single examination. Two radiologists retrospectively reviewed respiratory-triggered and free-breathing sets (B50, B400, B800 diffusion weighted images and ADC map) in random order with a time interval of 2 weeks. Liver SNR and lesion-to-liver CNR of DWI were calculated measuring ROI. RESULTS: Total of 62 lesions (53 benign, 9 malignant) that included 32 cysts, 13 hemangiomas, 7 hepatocellular carcinomas (HCCs), 5 eosinophilic infiltration, 2 metastases, 1 eosinophilic abscess, focal nodular hyperplasia, and pseudolipoma of Glisson's capsule were reviewed by two reviewers. Though not reaching statistical significance, the overall lesion sensitivities were increased in respiratory-triggered DWI [reviewer1: reviewer2, 47/62(75.81%):45/62(72.58%)] than free-breathing DWI [44/62(70.97%):41/62(66.13%)]. Especially for smaller than 1 cm hepatic lesions, sensitivity of respiratory-triggered DWI [24/30(80%):21/30(70%)] was superior to free-breathing DWI [17/30(56.7%):15/30(50%)]. The diagnostic accuracy measuring the area under the ROC curve (Az value) of free-breathing and respiratory-triggered DWI was not statistically different. Liver SNR and lesion-to-liver CNR of respiratorytriggered DWI (87.6+/-41.4, 41.2+/-62.5) were higher than free-breathing DWI (38.8+/-13.6, 24.8+/-36.8) (p value <0.001, respectively). CONCLUSION: Respiratory-triggered diffusion-weighted MR imaging seemed to be better than free-breathing diffusion-weighted MR imaging on 1.5-T MR system for the detection of smaller than 1 cm lesions by providing high SNR and CNR.

Mesothelial Cyst of the Round Ligament Mimicking a Metastasis: a Case Report

A mesothelial cyst of the round ligament is a rare cause of an inguinal mass. Clinically, it is frequently misdiagnosed as one of commoner diseases such as an inguinal hernia, femoral hernia, lipoma, and lymphadenopathy upon physical examination. Some previous reports elaborated the sonographic features of a mesothelial cyst of the round ligament. However, to our knowledge, few reports have described the CT features of a mesothelial cyst. We illustrated here the sonographic and multidetector CT features of a case of a mesothelial cyst of the round ligament that presented as an inguinal palpable mass and mimicked a metastasis in a patient with a Sertoli-Leydig cell tumor of the ovary.

Diagnostic accuracy of 64-slice multidetector CT coronary angiography for the evaluation of coronary artery disease / 대한내과학회지

BACKGROUND/AIMS: Invasive coronary angiography remains the gold standard in the diagnosis of coronary artery disease. However, multidetector CT (MDCT) coronary angiography is an emerging technique that is available for the non-invasive detection of coronary artery stenoses. While the diagnostic accuracy of first generation MDCT is limited, recently released 64-slice MDCT has yielded promising results due to increased temporal and spatial resolution. The objective of this study was to investigate the diagnostic accuracy of non-invasive 64-slice MDCT for coronary artery disease. METHODS: One hundred one patients (63 males and 38 females; mean age, 63.7+/-10.5 years) undergoing conventional coronary angiography were included in this study. All coronary arteries, including the distal segments and side branches, were analyzed for the presence of significant stenosis (> or =50% diameter stenosis) and compared with of the quantitative coronary angiographic findings. RESULTS: Of the 1,440 coronary artery segments studied, 1,348 segments were assessed quantitatively by both MDCT and conventional coronary angiography (94%). Two hundred nine significant stenoses were detected by conventional coronary angiography. On a segment-based analysis, the senisitivity, specificity, and positive and negative predictive values of 64-slice MDCT were 96, 97, 85, and 99%, respectively. On a vessel-based analysis, the sensitivity, specificity, and positive and negative predictive values of 64-slice MDCT were 96, 97, 85, and 99%, respectively. The corresponding values obtained on a patient-based analysis were 100, 94, 97, and 100%, respectively. Coronary calcification was the major cause of false-positive findings. CONCLUSIONS: This study demonstrated that 64-slice MDCT coronary angiography is of similar accuracy as conventional coronary angiography for the detection of coronary artery disease. In selected groups of patients, 64-slice MDCT may replace the more invasive coronary angiography.

Cystic Solitary Fibrous Tumor Arising From the Left Occipital Meninges: A Case Report

Solitary fibrous tumor (SFT) is a benign mesenchymal neoplasm of a spindle-cell origin, and it usually involves the pleura. It's occurrence in various organs of the body has recently been described. Meningeal SFT is very rare. Radiologically, it is a strongly enhancing solid mass and is undistinguishable from fibrous meningioma and hemangiopericytoma. Yet we report here on a case of SFT with massive cystic degeneration that arose from the meninges of the left occipital region.

MR Findings of Subcutaneous Panniculitis-like T-Cell Lymphoma: A Case Report

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare cancer and it is widely regarded as being distinct from the other subtypes of peripheral T-cell lymphoma. SPTCL commonly presents with subcutaneous nodules that resembles panniculitis. The clinicopathologic features of SPTCL have recently been described. However, only a few cases with their CT and sonographic findings have been reported in the radiologic literature. We illustrate here the MR findings of this rare tumor in one case that presented with a popliteal mass.

Primary Extraskeletal Mesenchymal Chondrosarcoma Arising from the Pancreas

We report here on a case of primary extraskeletal mesenchymal chondrosarcoma that arose from the pancreas. A 41-year-old man was evaluated by CT to find the cause of his abdominal pain. The CT scans showed a heterogeneously enhancing necrotic mass with numerous areas of coarse calcification, and this was located in the left side of the retroperitoneal space and involved the body and tail of the pancreas. Portal venography via the celiac axis also showed invasion of the splenic vein. Following excision of the mass, it was pathologically confirmed to be primary extraskeletal mesenchymal chondrosarcoma that arose from the pancreas.

Metastatic Spinal Tumors: MR Findings after Novalis Radiosurgery

PURPOSE: To assess the therapeutic effect of Novalis radiosurgery for metastatic spinal tumors and evaluate the changes after treatment using MR imaging. MATERIALS AND METHODS: Between November 2003 and June 2005, 21 patients with metastatic spinal tumors underwent Novalis radiosurgery. Of these patients, the 7 with 13 metastatic spinal tumors who had undergone follow-up MR imaging were included in this study. The tumor locations were cervical spine in three, thoracic spine in four, lumbar spine in five and sacrum in one. During the first three months after Novalis radiosurgery, follow-up MRI was performed monthly and subsequently at 3-6-month intervals. On MR imaging, the volume of the tumors, the changes of their signal intensities and any changes in adjacent spinal cord were evaluated. RESULTS: Among the 13 lesions, 9 were decreased in volume (69.2%), 2 were stable (15.4%) and 2 were slightly increased. Seven of 9 lesions showed decreased signal intensity on T2 weighted images and 4 had compressive deformity. Two of 9 lesions had increased T2 signal intensity and tumor necrosis were detected on contrast-enhanced MR imaging. No changes in spinal cord were noted in any of the lesions. Those changes were detected on MRI obtained 1 month after Novalis surgery and the lesion sizes were gradually changed up to 3 months. CONCLUSION: Novalis radiosurgery was effective for the treatment of metastatic spinal tumor and the suppression of tumor growth. The estimation of therapeutic effect and detecting complication were precisely evaluated on MR imaging.

Clinical Evaluation of the JPEG2000 Compression Rate of CT and MR Images for Long Term Archiving in PACS

PURPOSE: We wanted to evaluate an acceptable compression rate of JPEG2000 for long term archiving of CT and MR images in PACS. MATERIALS AND METHODS: Nine CT images and 9 MR images that had small or minimal lesions were randomly selected from the PACS at our institute. All the images are compressed with rates of 5:1, 10:1, 20:1, 40:1 and 80:1 by the JPEG2000 compression protocol. Pairs of original and compressed images were compared by 9 radiologists who were working independently. We designed a JPEG2000 viewing program for comparing two images on one monitor system for performing easy and quick evaluation. All the observers performed the comparison study twice on 5 mega pixel grey scale LCD monitors and 2 mega pixel color LCD monitors, rspectively. The PSNR (Peak Signal to Noise Ratio) values were calculated for making quantitative comparisons. RESULTS: On MR and CT, all the images with 5:1 compression images showed no difference from the original images by all 9 observers and only one observer could detect a image difference on one CT image for 10:1 compression on only the 5 mega pixel monitor. For the 20:1 compression rate, clinically significant image deterioration was found in 50% of the images on the 5M pixel monitor study, and in 30% of the images on the 2M pixel monitor. PSNR values larger than 44 dB were calculated for all the compressed images. CONCLUSION: The clinically acceptable image compression rate for long term archiving by the JPEG2000 compression protocol is 10:1 for MR and CT, and if this is applied to PACS, it would reduce the cost and responsibility of the system.

Exogastric Mature Teratoma in an Infant: A Case Report

Gastric teratomas are extremely rare neoplasms that have clinical characteristics such as a male predominance and a benign nature. We experienced a case of mature gastric teratoma occurring in a 12-month-old boy, who presented with an exogastric cystic mass, and this was confirmed by complete excision with subsequent pathologic examination. We report here on the radiologic and pathologic findings of an exogastric mature teratoma in an infant.

Three-dimensional image of patent ductus arteriosus reconstructed by 64-slice multidetector CT / 대한내과학회지

No abstract available.

Primary Systemic Amyloidosis Presenting as Swollen Dense Breast: A Case Report

Breast involvement of primary systemic amyloidosis is rare. This is a rare case of breast amyloidosis presenting as a diffuse infiltrative lesion. We present the mammographic, ultrasound, and MR findings of a systemic primary amyloidosis involving the breast with diffuse infiltrative pattern.

The Usefulness of Venous Color Doppler with Valsalva Maneuver for Varicose Vein

PURPOSE: We wanted to evaluate the usefulness of venous color Doppler with performing a Valsalva maneuver for chassifing primary varicose vein of the lower extremity. MATERIALS AND METHODS: From September 2002 to March 2005, 207 patients and 288 extremities that were clinically suggestive of primary varicose vein in the lower extremity underwent venous color Doppler with performing a Valsalva maneuver. The patients included 133 women and 74 men aged between 20-79 years (mean age: 51 year). Color Doppler study was performed in the great and small saphenous veins. We used a 5 point grading system, Grade (Gr.) 0 was no evidence of reflux, Gr. I was early reflux within 3 seconds after the Valsalva maneuver, Gr. II was continuous reflux without dilatation during the Valsalva maneuver, Gr. III was continuous reflux with dilatation during the Valsalva maneuver and Gr. IV was reflux at a resting state. To find a relationship between the rate of operation and the grading system, we retrospectively reviewed the patient's medical records and the grading system. RESULTS: In the great saphenous vein, Gr. 0 was noted in 42 cases, Gr. I was noted in 68 cases, Gr. II was noted in 23 cases, Gr. III was noted in 104 cases and Gr. IV was noted in 51 cases. In the small saphenous vein, Gr. 0 was noted in 98 cases, Gr. I was noted in 60 cases Gr. II was noted in 38 cases, Gr. III was noted in 36 cases and Gr. IV was noted 56 cases. Among these cases, 2 cases of Gr. 0, 9 cases of Gr. I, 3 cases of Gr. II, 85 cases of Gr. III and 44 cases of Gr. IV of the great saphenous vein were operated on. 3 cases of Gr. 0, 4 cases of Gr. I, 4 cases of Gr. II, 23 cases of Gr. III and 37 cases of Gr. IV of the small saphenous vein were also operated on. Consequently, the operation rate was 76.5% in the severe cases over Gr. III. CONCLUSION: Color Doppler with performing a Valsalva maneuver and our new grading system is a useful method to determine the rate of operation for the patients suffering with primary varicose vein.

Web Based Emergency Room PACS

PURPOSE: We wished to develop the web based Picture Archiving and Communication System in the emergency room for early decision making in emergency treatment planning at a full PACS Hospital. MATERIALS AND METHODS: The program tools were Microsoft Visual Studio 6.0 - Visual C++ 6.0, and the Microsoft SQL 7.0 under the Microsoft Windows 2000 server(R) operation system. The achievement of images was performed by an auto transport program installed in the ER and the radiology department. RESULTS: The average compression rates were 5:1 for CT and MR, and 20:1 for CR with JPEG 2000 lossy compression. All the images were stored on hard disk for 3 months. The patients' information was displayed for 2 weeks for reducing the security risk. For interdepartmental consultation, patient query by patient hospital number was available. CONCLUSION: Our Web based ER PACS could be useful system for early decision making for treatment planning in the emergency room because it reduces the risk factors for the security of the Web PACS by using a system independent from PACS in the hospital and minimizing the information patients.

Radiological Findings of Giant Pulmonary Chondromatous Hamartoma: Case Report

Among lung tumors, multiple hamartomas are uncommon and multiple chondromatous hamartomas are extremely rare. In this report, we describe a patient with an interval growth of a giant chondromatous hamartoma with accompanying multiple satellite nodules in the adjacent lung and the parietal pleura. We also present the follow up chest radiograph, computed tomograph, magnetic resonance images and photographs of the operating field of the tumor with pathologic correlation.

Retroperitoneal Lymphangiomyoma in a Patient with Pulmonary Lymphangiomyomatosis: Case Report

Retroperitoneal lymphangiomyoma is rare abdominal finding of lymphangiomyomatosis (LAM). We report here on a case of retroperitoneal lymphangiomyoma and this is the first case that? been seen in the Korean literature. Retroperitoneal lymphangiomyoma associated with pulmonary LAM has rarely been reported in radiologic literature. The charateristic findings of this case are a prominent solid component and retroperitoneal lymphadenopathy mimicking a malignant tumor. A 45-year-old woman was admitted for further evaluation of a lower abdominal mass that could be palpated for 2 weeks. US findings showed relatively well-defined mass with septated cystic portions and echogenic solid portions in the lower abdomen. CT findings revealed a well-demarked retroperitoneal mass with septated cystic portions and enhancing solid portions at the right lower abdomen, and there were multiple retroperitoneal lymphadenopathy at the lower abdomen. The patient underwent a mass excision. The pathologic findings were retroperitoneal lymphangiomyoma with multiple lymph node involvement.

Primary Malignant Melanoma of the Esophagus: Spiral CT and MR Findings: Case Report

Primary malignant melanoma of the esophagus is extremely rare, but must be included in the differential diagnosis of polypoid esophageal mass, when such a lesion is observed on radiological examination. We report here a case of primary malignant melanoma in the esophagus that was noted to have strong enhancement on CT and high signal intensity on the T1 weighted MR image.

Optimization of Digital Mammography Resolution Using Magnification Technique in Computed Radiography

PURPOSE: To determine whether magnified digital mammography using a computed radiography system can produce better spatial resolution by reducing the focus-object distance, and to define the optimal magnification factor when a large x-ray tube focal spot is used for digital mammography using a CR system. MATERIALS AND METHODS: Digital images obtained using computed radiography of a breast phantom were obtained using various magnification factors. Up to twelve acrylic blocks each measuring one centimeter in height were used to increase the distance between the breast phantom and the base plate (screen holder), in order to create the magnification images. The large (0.3 mm) focal spot of the x-ray tube was used for the entire series of images. Three radiologists participated in the evaluation of the images, in order to determine which had the best resolution. The resolving ability of the line pair structures and image clarity of the detectable artificial microcalcifications (specs) were the two factors used to determine the resolution of the images. The images were not compressed aFnd the viewing conditions, including the magnification factors, brightness and contrast, were fixed. The images were displayed on four high resolution PACS dedicated monitors (5 mega pixel LCD, BARCO Belgium). RESULTS: A focus-object distance of 590 mm and a source-to-image receptor distance of 650 mm (set by the manufacturer) resulted in the best resolution, when combined with a magnification factor of 1.1. All three radiologists agreed on this result. Two of the radiologists believed that at least two more line pairs were better separated on the magnified image having the best resolution than on the unmagnified image, while one radiologist believed that three more line pairs were better separated on this magnified image. Using images with still larger magnification factors did not improve the resolution due to edge blurring. It was easier to determine the resolving power by means of the line-pair structures than by assessing the clarity of the artificial microcalcifications (specs). A 10% decrease in focal spot-object distance resulted in a 21% increase in radiation to the breasts. CONCLUSION: Magnified digital breast images taken with a computed radiography system using a large focal spot produced better quality images, because of their utilizing more pixels per volume of the breast phantom with a minimal increase in radiation dosage.

Idiopathic Spontaneous Pneumomediastinum: Radiologic and Clinical Features

PURPOSE: To evaluate the clinical presentations, radiological characteristics, and natural history of healthy adolescents presenting with idiopathic spontaneous pneumomediastinum. MATERIALS AND METHODS: We retrospectively reviewed the simple radiographs of 14 consecutive patients (11 males) with spontaneous pneumomediastinum, who were examined over a period of 8 years, and analyzed their clinical history, radiographic findings including distribution, combined subcutaneous emphysema, mediastinal widening, pneumothorax, pleural effusion, and resolving period on follow up chest radiographs. We also obtained CT images of 7 patients for the assessment of additional information. RESULTS:The most common complaint at the time of presentation was chest pain and chest discomfort (8/14), followed by neck discomfort (6/14). The chest radiograph was of diagnostic value in all cases. The main distribution of the pneumomediastinum was cervical (14/14), upper lung (13/14) and lower lung (6/14). Combined subcutaneous emphysema was observed in 6 patients. However, there were no cases of mediastinal widening, pneumothorax or pleural effusion. Complete resolution of the pneumomediastinum on the radiograph was observed after 10 days (mean 5.6), following purely conservative treatment. There was no additional information on the CT images, as compared with that on the radiographs. Conclusions: Idiopathic spontaneous pneumomediastinum is a benign entity that usually goes undiagnosed, but which responds very well to conservative treatment.