Sonographic evaluation of renal transplant complications.

Renal transplants are the most frequent visceral transplant, and because of the absence of nephrotoxicity and radiation, ultrasound is widely used to monitor grafts and assess for complications. Complications can be categorised as vascular, parenchymal, ureteric and perinephric collections, with many occurring at predictable times post transplant. Awareness of these pathologies and their features is vital for all radiologists to enable early intervention and prolong graft survival.

Abdomen's forgotten organ: Sonography and CT of focal splenic lesions.

Focal lesions within the spleen are being increasingly recognized as imaging technologies advance, and often provide a diagnostic challenge for radiologists. Knowledge of the types of pathologies that occur, determination of solid or cystic nature and a search for characteristic features including correlation with extrasplenic findings can usually allow a specific diagnosis or brief differential to be offered.

Extranodal lymphoma in the thorax: cross-sectional imaging findings.

The purpose of this review is to discuss and illustrate the spectrum of appearances of extranodal lymphoma in the thorax, including the lungs, pleura, heart, thymus, chest wall, thoracic spine, and breast, using current cross-sectional imaging techniques, such as multidetector computed tomography, positron-emission tomography/computed tomography, magnetic resonance imaging, and sonography. Extranodal lymphoma can affect any organ or tissue in the thorax, and can be mistaken for other inflammatory or neoplastic conditions. This review should alert the radiologist to consider extranodal lymphoma in the appropriate clinical setting to ensure timely diagnosis, correct staging, and accurate post-treatment evaluation to optimize treatment regimens.

Multidetector CT pulmonary angiography features of pulmonary embolus.

Pulmonary embolism (PE) is a life-threatening condition. Multidetector CT pulmonary angiography is currently the imaging method of choice for the detection of PE. The aim of this pictorial essay is to review the appearances of PE on multidetector CT pulmonary angiography, including signs that differentiate acute and chronic PE and markers of severity. The features of a non-diagnostic study and pitfalls leading to a false-positive or false-negative study are presented.

Developing the image interpretation skills of South Pacific radiographers: a joint WHO/RANZCR/ISRRT project.

There is a shortage of radiologists in the Pacific Island nations. To help 'fill the gap', a project was conducted between 2004 and 2006 aimed at upskilling radiographers from South Pacific countries in basic radiological interpretation of plain film radiographs. It was intended that the radiographers would act as a resource, identifying and describing abnormalities to the local doctors and nurses, thus reducing the risk of misdiagnosis. A total of 23 participants, including one doctor and three health-care assistants, attended a 2-week course in 2004 or 2005. The course covered common abnormalities of the musculoskeletal system, chest and abdomen. Although they found the course challenging, most participants performed satisfactorily. Follow-up visits to the radiographers and their nominated, medically qualified mentors emphasized interprofessional, sociocultural and workload challenges experienced by some of the radiographers in implementing their extended role. Most of them, however, had found ways to integrate their new knowledge and skills into their clinical practice. Thirteen radiographers attended a further 1-week refresher course in 2006, showing their commitment to continued learning.

Computed tomography of intrathoracic extramedullary haematopoiesis occurring as a complication of osteopetrosis.

Intrathoracic extramedullary haematopoiesis occurring as a complication of osteopetrosis is uncommon. The combination of classic plain film and CT findings should suggest the diagnosis, which can be non-invasively confirmed with bone marrow scintigraphy.

Computed tomography manifestations of peritoneal diseases.

The peritoneal cavity is a potential space that is divided by the peritoneal reflections into various complex subspaces. It can be involved in many disease processes including developmental, inflammatory, neoplastic and traumatic conditions. Computed tomography is highly sensitive and consistent in detecting peritoneal pathology. This pictorial essay aims to emphasize and illustrate the CT features of the spectrum of peritoneal diseases.

Plasma amino-terminal pro-brain natriuretic peptide levels in subjects presenting to the Emergency Department with suspected acute coronary syndrome: possible role in selecting patients for follow up?

BACKGROUND: Plasma amino-terminal pro-brain natriuretic peptide (NT-proBNP) level is a sensitive and specific indicator of cardiac dysfunction. AIM: To determine whether plasma NT-proBNP level is elevated at the time of presentation with acute coronary syndrome (ACS) and whether it may assist in the diagnosis of heart failure and myocardial ischaemia in the Emergency Department. METHODS: Plasma NT-proBNP levels were measured prospectively in 201 unselected presentations to the Emergency Department with suspected ACS where cardiac injury markers were requested by clinicians as part of routine assessment. NT-proBNP levels were correlated with clinical, electrocardiogram (ECG), biochemical and radiological findings. RESULTS: Elevated NT-proBNP level detected heart failure with high sensitivity (95-96%). Among patients without heart failure, NT-proBNP levels were increased more frequently in patients with previously diagnosed ischaemic heart disease. Elevated NT-proBNP level predicted cardiomegaly and a cardiac cause of presentation. However, the NT-proBNP level was not associated with ECG or biochemical markers of myocardial ischaemia, and only one-third of patients with ACS showed an increase of 40% or more in NT-proBNP level at repeat measurement of cardiac injury markers 5 h after presentation. CONCLUSIONS: Although elevated NT-proBNP level detected heart failure with high sensitivity, NT-proBNP level did not assist in the diagnosis of acute myocardial ischaemia. These findings indicate that the major determinant of elevated NT-proBNP level on presentation with suspected ACS was underlying cardiac dysfunction rather than acute myocardial ischaemia. This suggests that NT-proBNP measurement in patients with a suspected cardiac reason for presentation to the Emergency Department may identify a previously unrecognized group of patients without acute ischaemia who may nevertheless benefit from further investigation of cardiac function.

The beneficial effect of heparin in preischemic perfusion solutions for cold-stored skin flaps.

Storage of skin flaps in the cold before replantation increases their tolerance to ischemic damage. Rat epigastric skin flaps were perfused immediately before 2 days of cold ischemia with 3 ml of normal saline containing either 10 U per milliliter of heparin (group 1, N = 11) or normal saline (group 2, N = 10), or stored without perfusion (group 3, N = 6), and replanted. Flap viability was assessed 7 days later. The mean flap survival in groups 1, 2, and 3 was 73% (p<0.01 compared with group 2), 10%, and 33% respectively. Intravascular fibrin deposits were detected histochemically 5 minutes before reperfusion in nonperfused flaps and 5 minutes after reperfusion in saline-perfused flaps, but not in flaps perfused with heparinized saline. Angiography revealed evidence of no reflow in the first 5 minutes of reperfusion in saline-perfused flaps, but normal blood flow in heparinized saline-perfused flaps. Tissue water content, myeloperoxidase activity, and hydroperoxide levels after 1 and 24 hours of reperfusion were not significantly different in flaps perfused with heparinized saline and normal saline. These findings indicate that in skin flaps perfused before ischemia, flaps perfused with heparinized saline survive significantly better than flaps perfused with normal saline. They also survive better than nonperfused flaps but the improvement is not significant.

F-18 fluorodeoxyglucose positron emission tomography in the non-invasive staging of non-small cell lung cancer.

OBJECTIVE: Positron emission tomography (PET) using F-18 fluorodeoxyglucose (FDG), a glucose analogue, as a metabolic tumour marker, has been proposed for the non-invasive staging of oncological disease. Tumours demonstrate increased glycolytic activity and thereby, FDG PET can differentiate benign from malignant lesions. To determine its role in the mediastinal staging of patients with suspected non-small cell lung cancer, a prospective study of FDG PET and computed tomography (CT) compared to surgery and pathology was performed. The analysis group consists of 50 patients, 37 men and 13 women, mean age 64 years (range, 41-78 years). METHODS: A nuclear physician, blind to the clinical and CT data, graded the FDG PET studies qualitatively on a five-point scale, based on the intensity of glucose uptake, for the presence of mediastinal nodal tumour involvement. Scores of four or greater were considered positive for tumour. An experienced radiologist interpreted the patients' CT scans blind to the other data. The CT criterion for tumour involvement was a nodal long axis diameter of 10 mm or greater. All patients underwent either thoracotomy or mediastinoscopy to obtain surgical specimens. The PET, CT, surgery and pathology were mapped according to the American Thoracic Society nodal classification resulting in 201 nodal stations evaluated. The imaging studies were analysed for N2 or N3 tumour involvement compared to histology or dissection of nodal stations. RESULTS: All patients had proven non-small cell lung carcinoma. PET excluded tumour in 175 of 181 nodal stations (specificity 97%) compared to 162 of 181 (specificity 90%) by CT. PET correctly identified 16 of 20 (sensitivity 80%) nodal stations with tumour compared to 13 of 20 by CT (sensitivity 65%). Overall, PET correctly staged 191 of 201 nodal stations (accuracy 95%) compared to 175 of 201 by CT (accuracy 87%). By the McNemar test, PET was significantly more specific than CT in excluding nodal tumour involvement (X2 = 5.5, P < 0.05). CONCLUSIONS: FDG PET is more specific than computed tomography in the non-invasive mediastinal staging of non-small cell lung cancer and has an important clinical role in the pre-operative staging of lung cancer patients.

Non-traumatic spinal extradural haematoma: magnetic resonance findings.

Non-traumatic extradural spinal haematoma is an uncommon condition that is usually associated with a poor outcome. It may present acutely with signs and symptoms of major neurological dysfunction secondary to cord compression, or subacutely over a number of days or weeks with fluctuating symptoms. The exact aetiology of this condition is incompletely understood, but it is believed that the blood is venous in origin, as distinct from the arterial origin of intracranial extradural haematomas. Causes of non-traumatic extradural spinal haematoma include anticoagulation, vasculitis such as systemic lupus erythematosus (SLE), and spinal arteriovenous malformations. Conditions that may mimic an acute spinal haematoma include extradural abscess and extradural metastatic infiltration. It is important to make a diagnosis of extradural compression because surgery may offer the best hope in restoring neurological function in these patients. Imaging modalities used for the investigation of extradural haematomas include myelography, CT myelography (CTM) and MRI with or without gadolinium enhancement. The MR appearances of acute extradural abscess and extradural tumour can mimic an extradural haematoma. In subacute haematoma, owing to the magnetic properties of blood degradation products, MR is more specific in diagnosing and ageing of the haematoma.

Imaging of the normal and abnormal pancreaticobiliary system with single-shot MR cholangiopancreatography: a pictorial review.

Magnetic resonance cholangiopancreatography (MRCP) is a rapidly evolving non-invasive imaging modality that produces images of the pancreatic duct and biliary tree without the need for intravenous or oral contrast. The images are equivalent to those from endoscopic retrograde cholangiopancreatography (ERCP), but the non-invasive acquisition avoids the morbidity and mortality associated with diagnostic ERCP. Magnetic resonance cholangiopancreatography is indicated in patients who require only a diagnostic ERCP, who fail an ERCP or who are unable to undergo ERCP due to altered post-surgical anatomy. Other evolving indications include triaging of patients with obstructive jaundice into percutaneous or endoscopic management drainage pathways depending on the site, length and nature of the duct obstruction, thereby potentially decreasing the number of failed or unsuccessful ERCP. Pre-operative identification of anomalous biliary anatomy and choledocholithiasis prior to laparoscopic cholecystectomy promise to modify the pre-operative and operative management of the patient in order to minimize the risk of duct injury and unnecessary intra-operative dissection and cholangiography. The advantages of the technique include its non-invasiveness, the absence of contrast administration, its relative operator independence and the ability to evaluate both sides of an obstructed duct, thereby accurately evaluating stricture morphology and length. The disadvantages of MRCP compared to ERCP include its lack of an immediate therapeutic solution to duct obstruction, procedural cost, unit availability and the inability to evaluate patients with pacemakers or ferromagnetic implants.

Magnetic resonance cholangiopancreatography: non-invasive imaging for the biliary tree and pancreatic duct.

Producing images similar to those acquired by the invasive procedures of endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic cholangiography, magnetic resonance cholangiopancreatography (MRCP) is indicated in patients who are unable to undergo ERCP or have had previously unsuccessful ERCP. It is used increasingly in non-invasive evaluation of the pancreaticobiliary tree in cases where the need for intervention during ERCP is expected to be low. MRCP may help in identifying anomalous biliary anatomy or choledocholithiasis before laparoscopic cholecystectomy, and in deciding between percutaneous or endoscopic treatment for patients with obstructive jaundice to decrease the rate of failed ERCP procedures.

Budd-Chiari syndrome: intractable ascites managed by a trans-hepatic portacaval shunt.

Transjugular intrahepatic portosystemic shunts (TIPS) have recently been used to manage the portal hypertensive complications of the Budd-Chiari syndrome. We report this application of TIPS (to our knowledge the first such application in Australia) in a young man with an excellent result and no major complications. This treatment offers an alternative to portacaval shunt surgery and has the advantage of bypassing a stenosed or compressed inferior vena cava. Additionally, the procedure does not complicate liver transplantation surgery if this is indicated at a later date.

Polyarteritis nodosa and antiglomerular basement membrane disease without antineutrophil cytoplasm antibodies.

Antiglomerular basement membrane (GBM) antibodies have been described previously in patients with microscopic polyarteritis but not in patients with polyarteritis nodosa alone. Where anti-GBM antibodies occur in microscopic polyarteritis, antineutrophil cytoplasm antibodies (ANCA) are usually present. We describe here a patient with polyarteritis nodosa and anti-GBM antibodies in whom ANCA could not be demonstrated. A 72-year-old woman presented with abdominal pain, diarrhoea and acute renal failure. A renal biopsy showed crescentic glomerulonephritis and linear immunofluorescence of the GBM consistent with anti-GBM disease. In addition, there was evidence of large-and medium-sized vessel vasculitis on abdominal angiography, performed because of persisting abdominal pain. There was no small vessel vasculitis on histological examination of the renal biopsy and ANCA could not be demonstrated by indirect immunofluorescence or ELISA.

The value of sonography in the diagnosis of traumatic rupture of the anterior cruciate ligament of the knee.

OBJECTIVE: The purpose of this study was to test the efficacy of sonography in the diagnosis of rupture of the anterior cruciate ligament in the setting of a recent traumatic hemarthrosis. SUBJECTS AND METHODS: Sonography was prospectively performed in 37 patients with a recent traumatic hemarthrosis of the knee, no bone abnormality seen on plain radiographs, and no history of a previous knee injury. The presence of a hypoechoic collection along the lateral wall of the femoral intercondylar notch was interpreted as a hematoma at the femoral attachment of the anterior cruciate ligament. Arthroscopy was subsequently performed in 30 patients. The findings of three diagnostic techniques (sonography, MR imaging, and arthroscopy) were compared. RESULTS: The sonographic findings were confirmed by MR imaging and arthroscopy in 34 of the 37 patients. For the three false-negative results, sonographic findings were abnormal but equivocal in two cases and were reported as negative. The technique was therefore 91% sensitive and 100% specific. The positive predictive value was 100%. The negative predictive value was 63%. CONCLUSION: Sonography is a useful and inexpensive method of detecting the presence of rupture of the anterior cruciate ligament in the clinical setting of a traumatic hemarthrosis.