N.E. Manghat

Multidetector row computed tomography: imaging congenital coronary artery anomalies in adults

The quality of the imaging of the main coronary arteries and side branches provided by multidetector row computed tomography (MDCT) may have importance when assessing congenital coronary artery anomalies. This review discusses the rationale for using MDCT for this indication and examines the advantages and disadvantages of the technique. Examples of MDCT imaging of congenital coronary artery anomalies are presented. These images provide persuasive evidence to support clinical use of MDCT cardiac imaging in the context of suspected congenital coronary artery anomalies as a first line investigation.

Imaging the pericardium: appearances on ECG-gated 64-detector row cardiac computed tomography

Multidetector row computed tomography (MDCT) with its high spatial and temporal resolution has now become an established and complementary method for cardiac imaging. It can now be used reliably to exclude significant coronary artery disease and delineate complex coronary artery anomalies, and has become a valuable problem-solving tool. Our experience with MDCT imaging suggests that it is clinically useful for imaging the pericardium. It is important to be aware of the normal anatomy of the pericardium and not mistake normal variations for pathology. The pericardial recesses are visible in up to 44% of non-electrocardiogram (ECG)-gated MDCT images. Abnormalities of the pericardium can now be identified with increasing certainty on 64-detector row CT; they may be the key to diagnosis and therefore must not be overlooked. This educational review of the pericardium will cover different imaging techniques, with a significant emphasis on MDCT. We have a large research and clinical experience of ECG-gated cardiac CT and will demonstrate examples of pericardial recesses, their variations and a wide variety of pericardial abnormalities and systemic conditions affecting the pericardium. We give a brief relevant background of the conditions and reinforce the key imaging features. We aim to provide a pictorial demonstration of the wide variety of abnormalities of the pericardium and the pitfalls in the diagnosis of pericardial disease.

Usefulness of 64-Detector Row Computed Tomography for Evaluation of Intracoronary Stents in Symptomatic Patients With Suspected In-Stent Restenosis

To determine whether 64-slice multidetector computed tomographic coronary angiography (MDCTA) can accurately assess the coronary artery lumen in symptomatic patients with previous coronary artery stents and potential in-stent restenosis (ISR). The primary aim was to determine the accuracy of binary ISR exclusion using MDCTA compared with invasive catheter angiography (ICA). Secondary aims were comparisons of stent dimensions measured using MDCTA and variables that affect accuracy. Forty patients with previous stent placement underwent both ICA and 64-slice MDCTA after elective presentation with chest pain, and ICA quantitative coronary angiographic data were used as the reference standard. Thirty-six men and 4 women (age 64 +/- 10 years; range 44 to 83) with 103 stents (2.8 +/- 1.6 stents/patient) were comparatively evaluated (stent exclusion rate 9.6%). There were 45 bare-metal and 58 drug-eluting stents (20 +/- 18 months after implantation) with an average diameter of 3.23 +/- 0.7 mm. Overall accuracy for the detection of significant ISR showed sensitivity, specificity, and positive and negative predictive values of 85%, 86%, 61%, and 96% for proximal stents > or =3 mm, which improved to 100%, 94%, 81%, and 100%; if the visible luminal diameter on MDCTA was <1.5 mm, accuracy decreased to 40%, 84%, 29%, and 90%, respectively. In conclusion, 64-slice MDCTA assessment of symptomatic patients with suspected clinically significant ISR is a realistic alternative to ICA if reference stent diameter is > or =2.5 mm and visible lumen cross-sectional diameter is > or =1.5 mm, for which a negative MDCTA result virtually excludes the presence of significant ISR.

Imaging the heart valves using ECG-gated 64-detector row cardiac CT.

Multi-detector row cardiac CT imaging demonstrates clinical usefulness in valvular heart disease, for which CT has not been traditionally used. Electrocardiographic (ECG)-gated CT coronary angiography also has an established clinical role with an increasingly solid evidence base, and the same data set in these patients also provides valuable information about chamber and valvular structure and function; this information should also be considered when interpreting cardiac CT and non-ECG gated thoracic imaging. Although true flow data cannot be achieved using CT, as with echocardiography and MRI, there are a number of imaging features that may be used when interpreting and inferring valve pathology. This article discusses the role of currently available imaging modalities and the rationale for cardiac CT, while focusing on the CT interpretation of valvular heart disease with respect to the relevant pathophysiology and management options that have importance to the radiologist. A suggested method of post-processing image review is provided with reference to a variety of normal and pathological pictorial illustrations.

Cardiomyopathy: appearances on ECG-gated 64-detector row computed tomography

Multi-detector row cardiac computed tomography (MDCT) with its high spatial and temporal resolution now has an established clinical role in cardiac imaging. The present review illustrates the MDCT appearances of cardiomyopathy, with reference to the normal myocardium, using multi-planar, near-isotropic imaging, three-dimensional volume rendering, and ECG-gated multi-phasic functional imaging software capabilities of 64-MDCT. MRI and echocardiographic correlations are also provided where appropriate.

Intramyocardial bridging of the left anterior descending artery: appearance of arterial compression on ECG gated multidetector row CT

A 38 year old man presented with a history of multiple hospital admissions with recurrent exertional related chest pain. On each occasion there was no elevation in cardiac troponin. Exercise stress testing revealed myocardial ischaemic change but coronary angiography failed to demonstrate underlying coronary disease although myocardial bridging of the left anterior descending artery (LAD) was suspected. ECG gated …

Pulmonary venous evaluation using electrocardiogram-gated 64-detector row cardiac CT.

OBJECTIVES Radiofrequency ablation of the pulmonary veins is an accepted treatment for atrial fibrillation. An accurate knowledge of pulmonary venous anatomy and dimensions is desirable prior to such a procedure. The objective of this study was to use 64-detector row cardiac CT to investigate the changes in pulmonary venous dimensions during the cardiac cycle. METHODS Data from 44 consecutive patients with no significant cardiovascular pathology who underwent electrocardiogram (ECG)-gated 64-detector row coronary angiography were retrospectively analysed. Average diameter and cross-sectional area were measured at 5 mm intervals from each pulmonary vein ostium, in ventricular end-diastole and ventricular end-systole, using curved multiplanar reformats. RESULTS 4 (9.1%) patients had pulmonary vein anomalies and were excluded. In the remaining 40 patients, pulmonary vein diameter and area at the ostium were significantly larger in end-systole in all four veins, with the largest differences in the superior pulmonary veins. Dimensional changes for diameter (millimetres) and area (square millimetres) were as follows: left superior pulmonary vein, 2.5 (p<0.001), 65.48 (p<0.001); right superior pulmonary vein, 1.63 (p<0.001), 56.27 (p<0.001); left inferior pulmonary vein, 1.1 (p<0.001), 30.41 (p<0.001); and right inferior pulmonary vein, 0.68 (p=0.005), 30.14 (p=0.005). Less marked changes were seen at measurement sites further from the atrium. Interobserver correlation was high (all but one measurement >0.9). CONCLUSION Pulmonary vein dimensions change significantly between end-systole and end-diastole, and the ostia of the superior pulmonary veins are potentially the most vulnerable to dimensional inaccuracies. ECG-gated cardiac CT may provide a more precise method of pulmonary venous dimensional measurement than non-gated techniques. Knowledge of change in pulmonary vein diameter offers interesting potential research into the effect of pulmonary vein function.

Incidental patent foramen ovale detected by 64-detector row CT before radiofrequency ablation therapy

This patient attended for pre-radio frequency ablation planning for drug refractory atrial fibrillation. The only abnormality demonstrated by transoesophageal echocardiography was a moderately dilated right atrium (RA). In our institution, 64-detector row computed tomography (CT) is now used as part of the pre-radio frequency ablation procedure. CT confirmed the transoesophageal echocardiography findings—normal …

Popliteal pseudoaneurysm secondary to a tibial osteochondroma: diagnosis with multi-detector row computed tomographic angiography.

A 17-year-old male presented with right knee pain following mild trauma whilst playing badminton. He subsequently developed a popliteal pseudoaneurysm secondary to trauma from a tibial osteochondroma. This is a recognised though very rare occurrence. Its appearance is reported for the first time using multi-detector row computed tomographic angiography (MDCTA). The clinical presentation and management of the popliteal pseudoaneurysm are outlined and the imaging findings are illustrated. There is increasing usefulness of MDCTA as an accessible, accurate, non-invasive clinical tool in the emergency diagnostic setting. Its use in the management of this unusual condition is demonstrated with emphasis on 3D, multi-planar reconstruction post-processing techniques.

A Pictorial Review of Splenic Pathology at Ultrasound: Patterns of Disease

When evaluating the spleen at ultrasound, the temptation is to measure splenic size, which, if normal, leads to further assessment of splenic shape, position and echotexture being often neglected. However, the spleen is commonly involved in a wide variety of pathological conditions. Some of these processes cause isolated splenic disease, whereas others involve the spleen as part of a systemic illness, heralding pathology in other organs.