Benign cardiac tumours: cardiac CT and MRI imaging appearances.

Primary benign cardiac tumours are rarely found in clinical practice and are generally evaluated with echocardiography. However, with the increasing usage of helical multislice CT, the initial detection and evaluation of these masses may be made by the radiologist during routine daily practice for other indications. The echocardiographic, CT and cardiac MRI appearances of various benign cardiac tumours and masses are described and illustrated in this review.

Portal vein thrombosis with unusual hepatic enhancement pattern: diagnosis using 64-slice multidetector computed tomography and 3 Tesla magnetic resonance imaging.

Portal vein thrombosis is a potentially life-threatening condition with occasionally uncertain clinical symptoms and signs. Consequently, the diagnosis may be first made by the radiologist using cross-sectional imaging modalities. A case of extensive portal venous system thrombosis extending into the superior mesenteric vein associated with an unusual pattern of central hepatic enhancement imaged by both 64-slice multidetector CT and 3 Tesla MRI is presented with a discussion of the imaging features of both modalities.

Coronary artery anomalies diagnosed by magnetic resonance angiography.

Coronary artery anomalies are uncommon entities that may be associated with sudden death. Because of its 2-D projection imaging nature, conventional X-ray coronary angiography may not accurately delineate the origins and course of aberrant coronary arteries with respect to the great vessels. Non-invasive, cross-sectional imaging techniques such as coronary CT angiography and magnetic resonance angiography are increasingly used in clinical practice to diagnose coronary artery anomalies. Although this study reviews coronary artery anatomy and selected anomalies as seen with true fast imaging with steady-state precession magnetic resonance angiography, the information provided is equally applicable to electrocardiogram-gated coronary CT angiography.

Magnetic resonance imaging of acute myocardial infarction in dextrocardia with situs solitus (dextroversion).

The case report of an 88-year-old woman with dextroversion and acute anterior wall myocardial infarction is presented. The patient, who had been diagnosed with dextrocardia 3 years prior to this admission, presented with right-sided chest pain. Coronary angiography demonstrated an 80% proximal left anterior descending artery stenosis which was successfully stented. A cardiac MRI was performed to exclude a left atrial thrombus after an inconclusive echocardiogram. The MRI demonstrated findings consistent with dextroversion, with delayed contrast-enhanced viability sequences confirming a near transmural anterior wall myocardial infarct. To our knowledge, this is the first report illustrating the cardiac MRI findings in such a case.

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.

MR angiography of aberrant left subclavian artery arising from right-sided thoracic aortic arch.

Right-sided thoracic aortic arch with aberrant left subclavian artery is an uncommon entity that is usually asymptomatic, but may present in adults with symptoms of dysphagia. Cross-sectional imaging such as CT or MR is often required to conclusively diagnose this condition, which may be suggested by chest radiograph or barium swallow. MRI including TRICKS (time-resolved imaging of contrast kinetics) magnetic resonance angiography (MRA) was utilized in the evaluation of a 40-year-old man presenting with dysphagia and abnormal barium swallow study. TRICKS MRA is a recently developed MRA technique, which can provide multiple high-resolution images of the thoracic vessels with a high temporal resolution without the need for timing doses of gadolinium contrast or multiple injections.

133Xenon ventilation scintigraphy applied to bronchoscopic lung volume reduction techniques for emphysema: relevance of interlobar collaterals.

BACKGROUND: 133Xenon ventilation scintigraphy and (99m)Tc-MAA perfusion scintigraphy can be used to assess dynamic ventilation patterns in patients with severe emphysema. AIM: To describe the scintigraphic features of attempted bronchoscopic lung volume reduction (BLVR), exploring mechanisms that might explain the unexpected lack of postoperative atelectasis. METHODS: Five patients with heterogenous severe upper lobe emphysema were evaluated with 133Xenon ventilation and (99m)Tc-MAA perfusion scintigraphy, chest radiography, bronchoscopy and high resolution computed tomography before and up to 1 month after endoscopic placement of bronchial prostheses (BLVR). Ex vivo assessment of the lungs of two further patients with severe upper lobe emphysema was performed. RESULTS: No significant subsegmental or lobar collapse was evident on post-procedure chest radiography or high resolution computed tomography, despite bronchoscopic confirmation of adequate position and functioning of prostheses. 133Xenon ventilation scintigraphy confirms significantly decreased upper lobe wash-in (P < 0.023), unchanged lower lobe wash-in and significantly increased lower lobe wash-out rates (P < 0.005) after BLVR. Significant redistribution of perfusion to the lower lobes occurred after BLVR (P < 0.025). Ex vivo experiments on explanted emphysematous lungs demonstrated that these findings could best be explained by collateral interlobar ventilation, which was calculated in one specimen to be as high as 15% of total lower lobe ventilation. Peri-valvular leak is a much less likely possibility. CONCLUSION: 133Xenon ventilation scintigraphy indicated the presence of significant interlobar collateral ventilation in patients with severe emphysema that may have major relevance to these novel alternative techniques to lung volume reduction surgery. 133Xenon scintigraphy can be used in the evaluation of severe emphysema before and after novel therapeutic interventions.

Non-vascular intervention with real-time CT fluoroscopy.

The emerging technology of CT fluoroscopy (CTF) represents the first opportunity for real-time CT guidance in non-vascular intervention. As with any new technology, its efficacy requires validation before widespread application can be advocated. A review of our initial experience is presented with particular attention to room, procedure and fluoroscopy time savings, complication rates and dosimetry. Computed tomography fluoroscopy is useful for pulmonary, pelvic, retroperitoneal and other deep organ lesions that are not easily accessible by other modalities. Computed tomography fluoroscopy decreases procedure time by at least a factor of 2 compared with conventional CT (C-CT) guidance, resulting in improved throughput in a busy interventional CT department. Accurate targeting of small lesions, previously considered inaccessible, can also be achieved with CTF. Exposure to the physician's hands can be reduced to a level that is acceptable to the International Commission on Radiological Protection guidelines.

Multifocal malignant extra-adrenal paragangliomas of the Organ of Zuckerkandl and urinary bladder.

A case of multifocal malignant extra-adrenal paragangliomas involving the Organ of Zuckerkandl and urinary bladder is presented. The role and order of imaging investigations of functioning extra-adrenal paraganglioma is discussed.