The Assessment of Cardiac Masses by Cardiac CT and CMR Including Pre-op 3D Reconstruction and Planning.

PURPOSE OF REVIEW: The purpose of this review is to (1) review the recent evidence examining the use of CT and CMR in the assessment of a suspected cardiac mass, (2) summarize the typical imaging features of the most common cardiac masses, and (3) examine the latest developments in the use of three-dimensional reconstructions and models in the preoperative assessment of a cardiac mass. RECENT FINDINGS: CMR can distinguish between tumors and non-tumor masses and between benign and malignant mass with a high degree of accuracy. CT and CMR are complementary tools in the evaluation of cardiac masses. CMR is the preferred initial imaging modality due to its versatile imaging planes and superior tissue characterization. CT better depicts calcification and has a higher spatial resolution compared with CMR, which is of particular importance in preoperative planning. CT also offers a valuable alternative in those with contraindications to CMR. Three-dimensional reconstructions, particularly of CT datasets, are a valuable adjunct in the preoperative assessment of a cardiac mass and may allow a better appreciation of the margins of the mass and its relationship with surrounding structures. Three-dimensional printing is an emerging technology which may be of additional value in selected patients with a cardiac mass.

Out of Hours Emergency Computed Tomography Brain Studies: Comparison of Standard 3 Megapixel Diagnostic Workstation Monitors With the iPad 2.

PURPOSE: The purpose was to compare performance of diagnostic workstation monitors and the Apple iPad 2 (Cupertino, CA) in interpretation of emergency computed tomography (CT) brain studies. METHODS: Two experienced radiologists interpreted 100 random emergency CT brain studies on both on-site diagnostic workstation monitors and the iPad 2 via remote access. The radiologists were blinded to patient clinical details and to each other's interpretation and the study list was randomized between interpretations on different modalities. Interobserver agreement between radiologists and intraobserver agreement between modalities was determined and Cohen kappa coefficients calculated for each. Performance with regards to urgent and nonurgent abnormalities was assessed separately. RESULTS: There was substantial intraobserver agreement of both radiologists between the modalities with overall calculated kappa values of 0.959 and 0.940 in detecting acute abnormalities and perfect agreement with regards to hemorrhage. Intraobserver agreement kappa values were 0.939 and 0.860 for nonurgent abnormalities. Interobserver agreement between the 2 radiologists for both diagnostic monitors and the iPad 2 was also substantial ranging from 0.821-0.860. CONCLUSIONS: The iPad 2 is a reliable modality in the interpretation of CT brain studies in them emergency setting and for the detection of acute and chronic abnormalities, with comparable performance to standard diagnostic workstation monitors.

Incidental cardiac findings on thoracic imaging.

The cardiac structures are well seen on nongated thoracic computed tomography studies in the investigation and follow-up of cardiopulmonary disease. A wide variety of findings can be incidentally picked up on careful evaluation of the pericardium, cardiac chambers, valves, and great vessels. Some of these findings may represent benign variants, whereas others may have more profound clinical importance. Furthermore, the expansion of interventional and surgical practice has led to the development and placement of new cardiac stents, implantable pacemaker devices, and prosthetic valves with which the practicing radiologist should be familiar. We present a collection of common incidental cardiac findings that can be readily identified on thoracic computed tomography studies and briefly discuss their clinical relevance.

The relationship of body mass index and abdominal fat on the radiation dose received during routine computed tomographic imaging of the abdomen and pelvis.

PURPOSE: To determine the relationship of increasing body mass index (BMI) and abdominal fat on the effective dose acquired from computed tomography (CT) abdomen and pelvis scans. METHODS: Over 6 months, dose-length product and total milliamp-seconds (mAs) from routine CT abdomen and pelvis scans of 100 patients were recorded. The scans were performed on a 64-slice CT scanner by using an automatic exposure control system. Effective dose (mSv) based on dose-length product, BMI, periumbilical fat thickness, and intra-abdominal fat were documented for each patient. BMI, periumbilical fat thickness, and intra-abdominal fat were compared with effective dose. RESULTS: Thirty-nine men and 61 women were included in the study (mean age, 56.3 years). The mean BMI was 26.2 kg/m(2). The mean effective dose was 10.3 mSv. The mean periumbilical fat thickness was 2.4 cm. Sixty-five patients had a small amount of intra-abdominal fat, and 35 had a large amount of intra-abdominal fat. The effective dose increased with increasing BMI (P < .001) and increasing amounts of intra-abdominal fat (P < .001). For every kilogram of weight, there is a 0.13 mSv increase in effective dose, which is equal to 6.5 chest radiographs per CT examination. For an increase in BMI by 5 kg/m(2), there is a 1.95 mSv increase in effective dose, which is equal to 97.5 chest radiographs per CT examination. CONCLUSION: Increasing BMI and abdominal fat significantly increases the effective dose received from CT abdomen and pelvis scans.

Cardiac masses, part 1: imaging strategies and technical considerations.

OBJECTIVE: The objective of this article is to discuss optimal imaging strategies for the evaluation of cardiac masses. The advantages and disadvantages of echocardiography, cardiac MRI, gated cardiac CT, and nuclear imaging will be discussed and specific techniques presented. CONCLUSION: Multimodality imaging plays a pivotal role in the diagnosis and surgical planning of cardiac masses. Clinical features, such as patient age, location, and imaging characteristics of the mass will determine the likely differential diagnosis.

Cardiac masses, part 2: key imaging features for diagnosis and surgical planning.

OBJECTIVE: The objectives of this article are to discuss key radiologic features that differentiate primary and secondary cardiac masses. Clinical scenarios are included to highlight stepwise radiologic workup of tumors of the pericardium, epicardium, myocardium, valves, and chambers. The involvement of key cardiac anatomic structures will also be emphasized to determine resectability and guide surgical planning. CONCLUSION: Multimodality imaging plays a pivotal role in diagnosis and surgical planning of cardiac masses. Clinical features, such as patient age, location, and imaging characteristics of the mass will determine the likely differential diagnosis. In addition to radiologic evaluation of the mass itself, involvement of valvular apparatus, extent of myocardial involvement, or presence of associated coronary artery involvement is necessary to determine resectability and surgical technique.

To investigate dose reduction and comparability of standard dose CT vs Ultra low dose CT in evaluating pulmonary emphysema.

OBJECTIVES: The aim of this study was to investigate the extent of dose reduction and comparability of standard dose CT vs Ultra low dose CT in evaluating pulmonary emphysema. METHODS: Forty-nine patients with emphysema were recruited from a tertiary referral respiratory clinic. Each patient had a non-contrast Standard Dose (SD) and Ultra Low Dose (ULD) thoracic CT. The images were reconstructed using contemporary iterative reconstruction with a standard lung kernel. Lung volumes and emphysema severity was calculated using a commercially available automated densitometry segmentation package. The effective dose was calculated for both CT protocols. RESULTS: Automated densitometry calculated the total lung volume and percentage lung area of emphysema. The findings were highly comparable between ULD and SD protocols. A strong correlation was seen between ULD and SD images in measurement of total lung volume (R = 0.925, p < 0.001) and percentage lung involvement by densitometry (R = 0.940, p < 0.001). There is a 95% dose reduction with the ULD protocol, the mean effective dose is 0.12 ±â€¯0.09 mSv versus 2.33 ±â€¯1.54 mSv for the SD protocol. CONCLUSIONS: ULD thoracic CT is a comparable protocol for the assessment of emphysema severity relative to standard dose CT. ULD CT is performed at a 95% dose reduction compared to SD CT.

99mTc bone scintigraphy superscans: a review.

Whole-body bone scintigraphy (bone scan) using a (99m)Tc-labelled pharmaceutical is one of the most commonly performed radionuclide examinations. In the normal patient, both the osseous components of the skeletal system as well as the kidneys and bladder are visualized. A superscan is defined as a bone scan which demonstrates markedly increased skeletal radioisotope uptake relative to soft tissues, in association with absent or faint genito-urinary tract activity. While a superscan is relatively uncommon, its recognition is important, as it is associated with a number of important underlying diseases. The purpose of this review article is to describe the causes and variable features of a superscan and depict patterns which may aid in defining the underlying cause for the scan. In addition, we will discuss other investigations that may help further to identify the underlying disease in such cases.

Imaging features of intramural hematoma of the aorta.

Intramural hematoma (IMH) is defined as localized hemorrhage within the aortic wall and is included in the acute aortic syndrome spectrum with aortic dissection and penetrating aortic ulcer. The mortality from IMH is similar to classic aortic dissection (21%). 16% of patients with IMH will evolve to classic aortic dissection over time. Despite this confusion exists regarding the precise definitions and radiologic features of IMH versus penetrating ulcers with mural thrombus and overt aortic dissection.