MRI Findings of Intercostal Schwannoma: A Case Report

Intercostal schwannomas are uncommon, encapsulated neoplasms that originate in nerve sheaths of intercostal nerves. They account for less than 10% of primary neural tumors of the chest wall. Herein, we report a pathologically confirmed case of intercostal schwannoma with typical magnetic resonance imaging findings.

Intra-Appendiceal Air at CT: Is It a Useful or a Confusing Sign for the Diagnosis of Acute Appendicitis?

OBJECTIVE: To investigate the significance of intra-appendiceal air at CT for the evaluation of appendicitis. MATERIALS AND METHODS: We retrospectively analyzed 458 patients (216 men, 242 women; age range, 18-91 years) who underwent CT for suspected appendicitis. Two independent readers reviewed the CT. Prevalence, amount, and appearance of intra-appendiceal air were assessed and compared between the patients with and without appendicitis. Performance of CT diagnosis was evaluated in two reading strategies: once ignoring appendiceal air (strategy 1), and the other time considering presence of appendiceal air as indicative of no appendicitis in otherwise indeterminate cases (strategy 2), using receiver operating characteristic (ROC) analysis. RESULTS: Of the 458 patients, 102 had confirmed appendicitis. The prevalence of intra-appendiceal air was significantly different between patients with (13.2%) and without (79.8%) appendicitis (p < 0.001). The amount of appendiceal air was significantly lesser in patients having appendicitis as compared with the normal group, for both reader 1 (p = 0.011) and reader 2 (p = 0.002). Stool-like appearance and air-fluid levels were more common in the appendicitis group than in the normal appendix for both readers (p < 0.05). Areas under the ROC curves were not significantly different between strategies 1 and 2 in reader 1 (0.971 vs. 0.985, respectively; p = 0.056), but showed a small difference in reader 2 (0.969 vs. 0.986, respectively; p = 0.042). CONCLUSION: Although significant differences were seen in the prevalence, amount, and appearance of intra-appendiceal air between patients with and without appendicitis, it has a limited incremental value for the diagnosis of acute appendicitis.

Multidetector CT Findings of Bowel Transection in Blunt Abdominal Trauma

OBJECTIVE: Though a number of CT findings of bowel and mesenteric injuries in blunt abdominal trauma are described in literature, no studies on the specific CT signs of a transected bowel have been published. In the present study we describe the incidence and new CT signs of bowel transection in blunt abdominal trauma. MATERIALS AND METHODS: We investigated the incidence of bowel transection in 513 patients admitted for blunt abdominal trauma who underwent multidetector CT (MDCT). The MDCT findings of 8 patients with a surgically proven complete bowel transection were assessed retrospectively. We report novel CT signs that are unique for transection, such as complete cutoff sign (transection of bowel loop), Janus sign (abnormal dual bowel wall enhancement, both increased and decreased), and fecal spillage. RESULTS: The incidence of bowel transection in blunt abdominal trauma was 1.56%. In eight cases of bowel transection, percentage of CT signs unique for bowel transection were as follows: complete cutoff in 8 (100%), Janus sign in 6 (100%, excluding duodenal injury), and fecal spillage in 2 (25%). The combination of complete cutoff and Janus sign were highly specific findings in patients with bowel transection. CONCLUSION: Complete cut off and Janus sign are the unique CT findings to help detect bowel transection in blunt abdominal trauma and recognition of these findings enables an accurate and prompt diagnosis for emergency laparotomy leading to reduced mortality and morbidity.

Imaging Findings of Angiomyxolipoma of the Spermatic Cord Mimicking Inguinal Hernia

We report the case in a 72-year-old man who presented with a right inguinal mass and with a one month history that was initially interpreted as an inguinal hernia. Ultrasonography (US) and computed tomography (CT) demonstrated a right inguinal mass, including myxoid and fat component, extending from the right spermatic cord to the right inguinal subcutaneous layer. Mass excision was performed, and the diagnosis turned out to be angiomyxolipoma. Angiomyxolipoma is a rare tumor and the preoperative diagnosis of this disease is very difficult. However, angiomyxolipoma of the spermatic cord should be considered in the differential diagnosis in patients with an irreducible inguinal mass. Imaging diagnosis, such as US and CT may help to make a preoperative diagnosis.

Correlations of Dynamic Contrast-Enhanced Magnetic Resonance Imaging with Morphologic, Angiogenic, and Molecular Prognostic Factors in Rectal Cancer

PURPOSE: To investigate the correlations between parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and prognostic factors in rectal cancer. MATERIALS AND METHODS: We studied 29 patients with rectal cancer who underwent gadolinium contrast-enhanced, T1-weighted DCE-MRI with a three Tesla scanner prior to surgery. Signal intensity on DCE-MRI was independently measured by two observers to examine reproducibility. A time-signal intensity curve was generated, from which four semiquantitative parameters were calculated: steepest slope (SLP), time to peak (Tp), relative enhancement during a rapid rise (Erise), and maximal enhancement (Emax). Morphologic prognostic factors including T stage, N stage, and histologic grade were identified. Tumor angiogenesis was evaluated in terms of microvessel count (MVC) and microvessel area (MVA) by morphometric study. As molecular factors, the mutation status of the K-ras oncogene and microsatellite instability were assessed. DCE-MRI parameters were correlated with each prognostic factor using bivariate correlation analysis. A p-value of <0.05 was considered significant. RESULTS: Erise was significantly correlated with N stage (r=-0.387 and -0.393, respectively, for two independent data), and Tp was significantly correlated with histologic grade (r=0.466 and 0.489, respectively). MVA was significantly correlated with SLP (r=-0.532 and -0.535, respectively) and Erise (r=-0.511 and -0.446, respectively). MVC was significantly correlated with Emax (r=-0.435 and -0.386, respectively). No significant correlations were found between DCE-MRI parameters and T stage, K-ras mutation, or microsatellite instability. CONCLUSION: DCE-MRI may provide useful prognostic information in terms of histologic differentiation and angiogenesis in rectal cancer.

Sonographic Findings of Morel-Lavallee Lesions

PURPOSE: We reviewed the sonographic features of Morel-Lavallee lesions by correlating the US image findings with a lesion's age. MATERIALS AND METHODS: We obtained the sonography reports of 20 Morel-Lavallee lesions of the hip and extremities from 18 patients with a history of trauma. The US images were reviewed to characterize the echogenicity, shape, homogeneity, margins, location and size of the lesions. The results were correlated with the age of the lesions and the clinical histories. RESULTS: All the Morel-Lavallee lesions were hypoechoic or anechoic fluid collections located between the subcutaneous fat and the underlying fascia. Regarding the shape of the fluid collections, the lobular shaped lesions were all less than 21 days for the lesion's age, and the flat fluid collections were all greater than 1 month of age. Regarding the homogeneity, the heterogeneous fluid collections were all less than 25 days of age, and the homogeneous fluid collections were all greater than 1 month of age. CONCLUSION: A Morel-Lavallee lesion is seen as a posttraumatic fluid collection in the potential space between the subcutaneous fat and the underlying fascia on an ultrasound examination. Acute Morel-Lavallee lesions tended to be heterogeneous and lobular, and they became more homogeneous and flat in shape as the lesions evolved. Awareness of these imaging findings will help us to properly diagnose Morel-Lavallee lesions.

Diagnosis of Pancreatic Intraductal Papillary Mucinous Neoplasm / 대한소화기학회지

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a unique disease entity that is characterized by predominant intraductal growth of mucinous cells, copious mucin production, and subsequent cystic dilatation of pancreatic ducts. IPMN shows a spectrum of histologic and imaging findings and possesses as the potential for malignant transformation arising from adenoma to invasive carcinoma. It is important to determine the type, extent of duct involvement, and presence of malignant transformation, and to assess tumor grading prior to surgical resection. Thus, it would be helpful for physicians managing patients with IPMN of the pancreas to have a guideline for the diagnosis and treatment of IPMN. In this review, a role of radiological evaluation for diagnosis and preoperative assessment is described as well as presentation of the guideline for patient management.

Immunocytochemical Study for Detection of Lactoglobulin in Alveolar Macrophage of Cow Milk Aspirated Mouse / 소아알레르기및호흡기학회지

PURPOSE: It is difficult to detect small amount of aspiration into the lungs due to the lack of safe, sensitive and specific diagnostic tool. Recently, in animal studies, it has been reported that immunocytochemistry for lactoglobulin can be used to detect the minimal aspiration of cow milk. So, we tried to determine the difference between immunocytochemistry for lactoglobulin and Oil Red O stain of alveolar macrophages in cow milk aspirated mice. METHODS: Fifty seven mice with 6-8 weeks old and 30-40 g weighing were used. Mice received either single or multiple intranasal instillation of 0.05 ml cow milk for study and saline for control under the anesthesia with ketamine and xylazine. The trachea of mouse was cannulated with 20G Jelco needle and then, mouse lungs were lavaged 3 times with 0.5 ml of phosphate buffer solution at 4 hours, 12 hours, 24 hours after the last milk or saline instillation. Cells in bronchoalveolar lavage fluid(BALF) were stained with Oil Red O and immunocytochemistry for beta-lactoglobulin. RESULTS: After single aspiration of milk, no cellular difference was found in bronchoalveolar lavage fluid(BALF) when compared with saline aspirated group at 4 hours. But after repeated aspiration of milk, significant change was observed in the number of alveolar macrophage, neutrophil, lymphocyte and eosinophil. Immunocytochemical reactivity was not observed in alveolar macrophages of saline aspirated group. Lipid-laden alveolar macrophages were recovered rarely in Oil Red O staining. Immunocytochemical staining displayed stain-positive alveolar macrophages for beta-lactoglobulin at 4 hours after milk aspiration, it had a peak at 12 hours and decreased markedly at 24 hours. Immunocytochemical stain positive alveolar macrophages appeared similarly in number between single and repeated aspiration group. CONCLUSION: These observations suggested that alveolar macrophages could be detected more easily on immunocytochemistry for lactoglobulin than Oil Red O stain and immunocytochemistry could be used as a sensitive & specific diagnostic method for the detection of milk aspiration.

Primary Lymphoma of the Colon: Radiologic and Pathologic Findings

Compared with the stomach and small intestine, the colon and rectum are uncommon sites of lymphomatous involvement. Primary colorectal lymphoma is diagnosed when the lesion is confined to the colorectal area and regional lymph nodes, without involvement of other organs including the upper gastrointestinal tract, bone marrow, and distant lymph nodes. The radiologic appearance of primary lymphoma of the stomach and small bowel is well known, but in cases involving the colorectal area, this is not so. In this article, we categorize and illustrate the radiologic manifestations of primary colorectal lymphoma according to the findings of double-contrast barium enema and CT images, and describe the pathologic findings.

Virtual Colonoscopy with Electron Beam CT: Correlation with Barium Enema, Colonoscopy and Pathology

PURPOSE: To perform virtual colonoscopy using electron beam tomography(EBT) in potients in whom a colonicmass was present, and to compare the results with those obtained using barium enema, colonoscopy and grosspathologic specimens. MATERIALS AND METHODS: Ten patients in whom colonic masses were diagnosed by either bariumenema or colonoscopy were involved in this study. There were nine cases of adenocarcinoma and one of tubulovillousadenoma. Using EBT preoperative abdominopelvic CT scans were performed. Axial scans were then three-dimensionallyreconstructed to produce virtual colonoscopic images and were compared with barium enema, colonoscopy and grosspathologic specimens. Virtual colonoscopic images of the masses were classified as either 1)polypoid, 2)sessile,3)fungating, or 4)annular constrictive. We also determined whether ulcers were present within the lesions andwhether there was obstruction. RESULT: After virtval colonoscopy, two lesions were classified as polypoid, oneas sessile, five as fungating and two as annular constrictive. Virtual colonoscopic images showed good correlationwith the findings of barium enema, colonoscopy and gross pathologic specimens. Three of six ulcerative lesionswere observed on colonoscopy; in seven adenocarcinomas with partial or total luminal obstruction, virtualcolonoscopy visualized the colon beyond the obstructed sites. In one case, barium contrast failed to pass throughthe obstructed portion and in six cases, the colonoscope similarly failed. CONCLUSION: Virtual colonoscopiescorrelated well with barium enema, colonoscopy and gross patholoic specimens. They provide three dimensionalimages of colonic masses and are helpful for the evaluation of obstructive lesions.

MR Cholangiopancreatography: Comparison of Breath-hold Fast Spin Echo and Respiratory Triggered Fast Spin Echo Techniques

PURPOSE: To determine relative image qualities and to evaluate their ability to visualize biliary trees and pancreatic ducts, we compared the breath-hold fast spin echo (FSE) and respiratory triggered FSE technique in magnetic resonance cholangiopancreatography (MRCP). MATERIALS AND METHODS: Forty-seven patients with suspected of hepatic disease but no pancreatic or biliary ductal dilatation, as determined by other imaging techniques('group of pathologic pancreatobiliary tree') underwent MRCP. Heavily T2-weighted FSE coronal images were obtained by both breath-hold and respiratory triggered techniques. These two images were 3D-reconstructed using a maximal intensity projection algorithm. Three radiologists scored the image qualities of anatomic structures in each set of image, then directly compared the image quality of the images obtained by the two techniques. RESULTS: For the visualization of common hepatic ducts and common bile dvcts, FSE MRCP images obtained using the respiratory-triggered technique were triggered technique were significantly better than those obtained using the breath-hold technique (P<0.05). Fifty-nine to 88% of breath-hold images of the biliary tree and 63-95% of respiratory triggered images were optimal. For the pancreatic duct, however, 24% of breath-hold images and 15% of respiratory-triggered images provided optimal image quality. In direct comparison, respiratory triggered images were better in 25 cases (52.1%), both images were comparable in 12 cases (25.0%), and in 11 cases (22.9%), breath-hold images were better. These differences were statistically significant (p<0.05). CONCLUSION: For the vizualization of extrahepatic bile ducts, the respiratory triggered FSE sequence was better than the breath-hold sequence; for the evaluation of both a non-dilated and dilated pancreatobiliary system, however, both techniques need further development.

Knee MRI Study of Normal Cruciate Ligaments Comparing the Flexion Images with the Extension Images: Preliminary study

PURPOSE: As a baseline study for clinical application, we investigated MRI findings of normal cruciate ligaments in the knee being flexed as compared to those in the knee being extended. MATERIALS AND METHODS: Seven asymptomatic volunteers were studied. Knee MRI was performed with a 1.5 Tesla unit using a dual 3 inch coil. Inthe decubitus position, sagittal scanning was performed with the knee in extension, and subsequently, in flexion. We observed the shape and signal intensity of both cruciate ligaments, and measured the angles between the longaxis of the femur and ligaments, and the ligament dimensions in extension and flexion images. RESULTS: As flexionand extension images were compared, cruciate ligaments differed both in their appearance and dimensions. With flexion, joint space was widened, PCL became straightened and the signal intensity of ACL became homogeneously low; both cruciate ligaments became longer and thinner. These MRI findings were statistically significant except forthinning of PCL. CONCLUSION: MRI appearance and the dimensions of cruciate ligaments were different in the flexed knee as compared to those in the extended knee.

MR Findings of Central Nervous System Involvement in Acquired Immunodeficiency Syndrome Patient: A Report of Two Cases

Central nervous system (CNS) manifestations in acquired immunodeficiency syndrome (AIDS) patients are an earlyand common feature. The spectrum of AIDS-related CNS diseases are encephalitis caused by the human immunodeficiency virus(HIV) itself, opportunistic infection, infarct and malignancy. We experienced two cases of CNS involvement in AIDS and they were serologically diagnosed as HIV encephalitis and CNS toxoplasmosis, respectively. In the case of the HIV encephalitis patient, brain MRI showed a non-enhancing lesion with high signal intensity on T2WI and low signal on T1WI and there was no mass effect on the right frontal lobe,periventricular white matter, splenium of the corpus callosum or bilateral basal ganglia. In the other case of CNS toxoplasmosis, MR showed multiple nodular and rim enhanced mass lesions in the right basal ganglia, thalamus and periventricular white matter, which were of low signal intensity on T1WI and of high intensity on T2WI. We thus report the related MRI findings.

A Case of Mediastinal Gastroenteric Cyst

No abstract available.

A Case of Caverneous Lymphangioma

No abstract available.

A Case of Congenital Hepatic Fibrosis with Hypersplenism

No abstract available.