Imaging features of an intraosseous arteriovenous malformation in the tibia

Primary intraosseous arteriovenous malformations (AVMs) are rare and have only been occasionally reported. We herein report a histologically proven case of primary intraosseous AVM in the tibia, which mimicked a fibrous tumour on radiography. This presentation carries a risk of triggering acute large haemorrhage through unnecessary biopsy. In intraosseous AVM, the magnetic resonance (MR) imaging features typical of a soft tissue AVM are absent, making diagnosis difficult. In this report, peculiar MR features in the presence of a connecting vessel between the normal deep venous system of the lower extremity and the tumour provide a clue for the early diagnosis of primary intraosseous AVM.

Intra-arterial calcium stimulation test with hepatic venous sampling for preoperative diagnosis of a large insulinoma in an obese young man

Herein, we report the case of a large benign insulinoma in an obese young man with a three-year history of asymptomatic hypoglycaemia. He presented to our outpatient department with a two-week history of dizziness and morning cold sweats. A random serum glucose test revealed hypoglycaemia. Upon admission, computed tomography and magnetic resonance imaging of the abdomen with intravenous contrast media showed an enhancing mass lesion in the uncinate process of the pancreas. To confirm the diagnosis, an intra-arterial calcium stimulation test with hepatic venous sampling was performed for preoperative localisation and to exclude the presence of occult insulinomas. The patient underwent an exploratory laparotomy, with successful resection of the pancreatic head tumour. Histology confirmed the diagnosis of insulinoma. The patient's postoperative recovery was uneventful, and he has not developed further episodes of hypoglycaemia three years post surgery.

Docetaxel (Taxotere®)-induced cavitary change of pulmonary metastatic lesions complicated by bilateral spontaneous pneumothoraces in a patient with primary adenocarcinoma of the lung

Pneumothorax is a complication that rarely occurs after chemotherapy for lung cancer. We report the chest computed tomography findings of a case of spontaneous pneumothorax complicating docetaxel (Taxotere®) treatment for pulmonary metastasis in a 70-year-old woman with pulmonary adenocarcinoma. The patient developed bilateral pneumothoraces, which was induced by changes in the cavitary pulmonary metastatic lesions, after systemic chemotherapy with docetaxel. The chest computed tomography findings and possible mechanisms of this unusual complication are discussed in this report.

Case of Pulmonary Cryptococcosis Mimicking Hematogeneous Metastases in an Immuocompetent Patient: Value of Absent 18F-Fluorodeoxylucose Uptake on Positron Emission Tomography/CT Scan

The radiologic appearance of multiple discrete pulmonary nodules in immunocompetent patients, with cryptococcal infection, has been rarely described. We describe a case of pulmonary cryptococcosis, presenting with bilaterally and randomly distributed nodules on a computed tomography, mimicking hematogeneous metastases. Positron emission tomography does not demonstrate 18F-fluorodeoxyglucose (FDG) uptake, suggesting a low probability for malignancy, which is a crucial piece of information for clinicians when making a management decision. We find the absence of FDG uptake correlates with the pathologic finding of an infectious nodule, composed of fibrosis and necrosis.

Using Multidetector-Row CT for the Diagnosis of Afferent Loop Syndrome Following Gastroenterostomy Reconstruction

PURPOSE: To assess the clinical manifestations and multidetector-row computed tomography (MDCT) findings of afferent loop syndrome (ALS) and to determine the role of MDCT on treatment decisions. MATERIALS AND METHODS: From January 2004 to December 2008, 1,100 patients had undergone gastroenterostomy reconstruction in our institution. Of these, 22 (2%) patients were diagnosed as ALS after surgery that included Roux-en-Y gastroenterotomy (n=9), Billroth-II gastrojejunostomy (n=7), and Whipple's operation (n=6). Clinical manifestations and MDCT features of these patients were recorded and statistically analyzed. The presumed etiologies of obstruction shown on the MDCT were correlated with clinical information and confirmed by surgery or endoscopic biopsy. RESULTS: The most common clinical symptom was acute abdominal pain, presenting in 18 patients (82%). We found that a fluid-filled C-shaped afferent loop in combination with valvulae conniventes projecting into the lumen was the most common MDCT features of ALS. Malignant causes of ALS, such as local recurrence and carcinomatosis, are the most common etiologies of obstruction. These etiologies and associated complications can be predicted 100% by MDCT. CONCLUSION: Our results suggest that MDCT is a reliable modality for assessing the etiologies of ALS and guiding treatment decisions.

Intra-Arterial Treatment in Patients with Acute Massive Gastrointestinal Bleeding after Endoscopic Failure: Comparisons between Positive versus Negative Contrast Extravasation Groups

OBJECTIVE: To determine whether treatment outcome is associated with visualization of contrast extravasation in patients with acute massive gastrointestinal bleeding after endoscopic failure. MATERIALS AND METHODS: From January 2007 to December 2009, patients that experienced a first attack of acute gastrointestinal bleeding after failure of initial endoscopy were referred to our interventional department for intra-arterial treatment. We enrolled 79 patients and divided them into two groups: positive and negative extravasation. For positive extravasation, patients were treated by coil embolization; and in negative extravasation, patients were treated with intra-arterial vasopressin infusion. The two groups were compared for clinical parameters, hemodynamics, laboratory findings, endoscopic characteristics, and mortality rates. RESULTS: Forty-eight patients had detectable contrast extravasation (positive extravasation), while 31 patients did not (negative extravasation). Fifty-six patients survived from this bleeding episode (overall clinical success rate, 71%). An elevation of hemoglobin level was observed in the both two groups; significantly greater in the positive extravasation group compared to the negative extravasation group. Although these patients were all at high risk of dying, the 90-day mortality rate was significantly lower in the positive extravasation than in the negative extravasation (20% versus 42%, p < 0.05). A multivariate analysis suggested that successful hemostasis (odds ratio [OR] = 28.66) is the most important predictor affecting the mortality in the two groups of patients. CONCLUSION: Visualization of contrast extravasation on angiography usually can target the bleeding artery directly, resulting in a higher success rate to control of hemorrhage.

Incidentally Detected Enhancing Breast Lesions on Chest Computed Tomography

OBJECTIVE: To evaluate the nature and imaging appearance of incidental enhancing breast lesions detected on a routine contrast-enhanced chest CT. MATERIALS AND METHODS: Twenty-three patients with incidental enhancing breast lesions on contrast-enhanced chest CT were retrospectively reviewed. The breast lesions were reviewed by unenhanced and enhanced CT, and evaluated by observing the shapes, margins, enhancement patterns and backgrounds of breast lesions. A histopathologic diagnosis or long-term follow-up served as reference standard. RESULTS: Sixteen (70%) patients had malignant breast lesions and seven (30%) had benign lesions. In 10 patients, the breast lesions were exclusively detected on contrast-enhanced CT. Using unenhanced CT, breast lesions with fibroglandular backgrounds were prone to be obscured (p < 0.001). Incidental primary breast cancer showed an non-significant trend of a higher percentage irregular margin (p = 0.056). All of the four incidental breast lesions with non-mass-like enhancement were proven to be malignant. CONCLUSION: Routine contrast-enhanced chest CT can reveal sufficient details to allow for the detection of unsuspected breast lesions, in which some cases may be proven as malignant. An irregular margin of incidental enhancing breast lesion can be considered a suggestive sign of malignancy.

Perforated Sigmoid Colon Cancer within an Irreducible Inguinal Hernia: a Case Report

A perforated sigmoid colon cancer within an inguinal hernia is extremely rare. This unexpected finding is usually discovered during surgery and causes an unavoidable septic evolution. Here, we describe the case of an 84-year-old man who presented with fever, abdominal distension, and a painful, enlarged, left scrotum. A CT showed a left, incarcerated, inguinal hernia containing a perforated sigmoid adenocarcinoma (which was confirmed by histopathology). The possibility of an irreducible inguinal hernia in association with perforated sigmoid colon cancer should be considered in the array of diagnoses. A pre-operative CT scan would be helpful in facilitating an accurate diagnosis.

Atypical Pulmonary Metastases from a True Malignant Mixed Tumor of the Parotid Gland

A 58-year-old male patient presented with a recurrent true malignant mixed tumor of the parotid gland. Patchy pulmonary opacities were identified with a chest radiograph. Subsequently, a CT scan of the chest showed pulmonary parenchymal consolidation with amorphous calcifications. This abnormality was confirmed to be the result of a metastatic true malignant mixed tumor by using CT-guided biopsy. The current case demonstrated an extremely rare example of atypical pulmonary metastases from a true malignant mixed tumor of the parotid gland showing an air-space pattern and calcification.

An Unusual Radiologic Pattern of Cryptogenic Organizing Pneumonia: Diffuse Pulmonary Nodules in a Leukemia Patient

The radiological appearance of diffuse discrete pulmonary nodules associated with cryptogenic organizing pneumonia (COP) has been rarely described. We describe a case of COP in 49-year-old woman with acute myeloid leukemia who developed diffuse pulmonary nodules during the second course of induction chemotherapy. The clinical status of the patient and imaging findings suggested the presence of a pulmonary metastasis or infectious disease. A video-assisted thoracoscopic lung biopsy resulted in the unexpected diagnosis of COP as an isolated entity. Steroid therapy led to dramatic improvement of the clinical symptoms and the pulmonary lesions.