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Unilateral absence of pulmonary artery is a rare developmental anomaly. Infrahepatic inferior vena cava interruption is a well-recognized but uncommon developmental anomaly. Presence of both these anomalies in a single individual is extremely rare. A 58-year-old man with a history of recurrent lower extremity deep vein thrombosis and venous insufficiency presented to our emergency department with bilateral calf pain and swelling. Ultrasound demonstrated extensive deep vein thrombosis throughout bilateral lower extremities. Computed tomography angiography showed smooth tapering of the right pulmonary artery with absent distal most segment. To our knowledge, there is only 1 case report in the literature so far with both the abnormalities present in a single individual.

Magnetic resonance imaging (MRI) plays an increasingly important role in the non-invasive evaluation of the pulmonary vasculature. MR angiographic (MRA) techniques provide morphological information, while MR perfusion techniques provide functional information of the pulmonary vasculature. Contrast-enhanced MRA can be performed at high spatial resolution using 3D T1-weighted spoiled gradient echo sequence or at high temporal resolution using time-resolved techniques. Non-contrast MRA can be performed using 3D steady state free precession, double inversion fast spin echo, time of flight or phase contrast sequences. MR perfusion can be done using dynamic contrast-enhanced technique or using non-contrast techniques such as arterial spin labelling and time-resolved imaging of lungs during free breathing with Fourier decomposition analysis. MRI is used in the evaluation of acute and chronic pulmonary embolism, pulmonary hypertension and other vascular abnormalities, congenital anomalies and neoplasms. In this article, we review the different MR techniques used in the evaluation of pulmonary vasculature and its clinical applications.

Intracardiac metastasis of the testicular cancer is very rare phenomenon. A 30-year-old-man with a history of testicular rhabdomyosarcoma and lung metastases was found to have an intracardiac filling defect in a surveillance computed tomography scan 3 years after the initial diagnosis. A cardiac magnetic resonance imaging study was performed for further evaluation and demonstrated a lobulated, heterogeneously enhancing mobile mass within the right ventricle attaching to the anterior papillary muscle. Patient underwent an open surgical resection of the cardiac mass that was confirmed metastasis of testicular rhabdomyosarcoma into the right ventricular papillary muscle and tricuspid valve. To our knowledge, this is the first report in the literature that describes metastasis to a papillary muscle and tricuspid valve from a testicular neoplasm.

Objectives:To evaluate coronary artery calcification (CAC) on routine CT chest in hospitalised HIV patients and to assess individual risk factors.Methods:Routine CT chests, May 2010–November 2015, of 143 hospitalised HIV-positive patients were reviewed for qualitative assessment of calcification in major coronary arteries by two radiologists. Presence, location and burden of calcification were evaluated on 3 mm axial images of CT chest. Cardiovascular risk factors and HIV lab parameters such as CD4 count, viral load and duration, and status of antiretroviral treatment were collected. Statistical analysis including multivariate logistic regression was performed.Results:Forty-one patients (28.7%) showed CAC, left anterior descending (n = 38, 92.7%), circumflex (n = 18, 43.9%) and Right Coronary Artery (n = 13, 31.7%); mostly mild CAC burden and mostly proximal left coronary arteries with excellent interobserver and intraobserver agreements (K = 0.9, and 1). Age of CAC+ group (53.9 years) was significantly higher than CAC− group (43.4, p < 0.001, minimum age of CAC+, 27 years). No significant difference between two groups in sex, ethnicity and risk factors and HAART status. CAC+ group showed significantly longer HIV duration (12.3 years vs 8.6, p < 0.0344) and higher CD4 cell counts (mean = 355.9 vs 175.3, p = 0.0053) and significantly lower viral load (76 vs 414K, p = 0.02) than CAC− group. On multivariate logistic regression, age, HIV duration and CD4 were significantly associated with CAC+ (p-values < .05).Conclusions:One-third of hospitalised HIV patients showed subclinical CAC on CT chest. HIV duration and age of patients were independent risk factors for developing CAC. Higher CD4 cell count was strongly associated with CAC+.Advances in knowledge:Routine CT chest with or without contrast performed for non-cardiac indications is helpful in identification of subclinical CAC in HIV patients and radiologists should be encouraged to report CAC. CAC is seen in younger age group in HIV, and awareness of this finding on routine CT chest would help guiding clinicians to assess risk stratification for primary prevention of ischemic heart disease in this population at an earlier stage when compared to normal population. Duration of HIV infection and age of patients were independent risk factors for developing CAC in our study and CD4 count was strongly associated with presence of CAC.

PurposeTo summarize data on computed tomographic (CT) radiation doses collected from consecutive CT examinations performed at 12 facilities that can contribute to the creation of reference levels.Materials and methodsThe study was approved by the institutional review boards of the collaborating institutions and was compliant with HIPAA. Radiation dose metrics were prospectively and electronically collected from 199 656 consecutive CT examinations in 83 181 adults and 3871 consecutive CT examinations in 2609 children at the five University of California medical centers during 2013. The median volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose, along with the interquartile range (IQR), were calculated separately for adults and children and stratified according to anatomic region. Distributions for DLP and effective dose are reported for single-phase examinations, multiphase examinations, and all examinations.ResultsFor adults, the median CTDIvol was 50 mGy (IQR, 37-62 mGy) for the head, 12 mGy (IQR, 7-17 mGy) for the chest, and 12 mGy (IQR, 8-17 mGy) for the abdomen. The median DLPs for single-phase, multiphase, and all examinations, respectively, were as follows: head, 880 mGy · cm (IQR, 640-1120 mGy · cm), 1550 mGy · cm (IQR, 1150-2130 mGy · cm), and 960 mGy · cm (IQR, 690-1300 mGy · cm); chest, 420 mGy · cm (IQR, 260-610 mGy · cm), 880 mGy · cm (IQR, 570-1430 mGy · cm), and 550 mGy · cm (IQR 320-830 mGy · cm); and abdomen, 580 mGy · cm (IQR, 360-860 mGy · cm), 1220 mGy · cm (IQR, 850-1790 mGy · cm), and 960 mGy · cm (IQR, 600-1460 mGy · cm). Median effective doses for single-phase, multiphase, and all examinations, respectively, were as follows: head, 2 mSv (IQR, 1-3 mSv), 4 mSv (IQR, 3-8 mSv), and 2 mSv (IQR, 2-3 mSv); chest, 9 mSv (IQR, 5-13 mSv), 18 mSv (IQR, 12-29 mSv), and 11 mSv (IQR, 6-18 mSv); and abdomen, 10 mSv (IQR, 6-16 mSv), 22 mSv (IQR, 15-32 mSv), and 17 mSv (IQR, 11-26 mSv). In general, values for children were approximately 50% those for adults in the head and 25% those for adults in the chest and abdomen.ConclusionThese summary dose data provide a starting point for institutional evaluation of CT radiation doses.

Purpose To determine patient, vendor, and institutional factors that influence computed tomography (CT) radiation dose. Materials and Methods The relevant institutional review boards approved this HIPAA-compliant study, with waiver of informed consent. Volume CT dose index (CTDIvol) and effective dose in 274 124 head, chest, and abdominal CT examinations performed in adult patients at 12 facilities in 2013 were collected prospectively. Patient, vendor, and institutional characteristics that could be used to predict (a) median dose by using linear regression after log transformation of doses and (b) high-dose examinations (top 25% of dose within anatomic strata) by using modified Poisson regression were assessed. Results There was wide variation in dose within and across medical centers. For chest CTDIvol, overall median dose across all institutions was 11 mGy, and institutional median dose was 7-16 mGy. Models including patient, vendor, and institutional factors were good for prediction of median doses (R2 = 0.31-0.61). The specific institution where the examination was performed (reflecting the specific protocols used) accounted for a moderate to large proportion of dose variation. For chest CTDIvol, unadjusted median CTDIvol was 16.5 mGy at one institution and 6.7 mGy at another (adjusted relative median dose, 2.6 mGy [95% confidence interval: 2.5, 2.7]). Several variables were important predictors that a patient would undergo high-dose CT. These included patient size, the specific institution where CT was performed, and the use of multiphase scanning. For example, while 49% of patients (21 411 of 43 696) who underwent multiphase abdominal CT had a high-dose examination, 8% of patients (4977 of 62 212) who underwent single-phase CT had a high-dose examination (adjusted relative risk, 6.20 [95% CI: 6.17, 6.23]). If all patients had been examined with single-phase CT, 69% (18 208 of 26 388) of high-dose examinations would have been eliminated. Patient size, institutional-specific protocols, and multiphase scanning were the most important predictors of dose (change in R2 = 8%-32%), followed by manufacturer and iterative reconstruction (change in R2, 0.2%-15.0%). Conclusion CT doses vary considerably within and across facilities. The primary factors that influenced dose variation were multiphase scanning and institutional protocol choices. It is unknown if the variation in these factors influenced diagnostic accuracy. © RSNA, 2016.

Objective Dynamic changes in anatomic geometry of the inferior vena cava from changes in intravascular volume may cause passive stresses on inferior vena cava filters. In this study, we aim to quantify variability in inferior vena cava dimensions and anatomic orientation to determine how intravascular volume changes may impact complications of inferior vena cava filter placement, such as migration, tilting, perforation, and thrombosis. Methods Retrospective computed tomography measurements of major axis, minor axis, and horizontal diameters of the inferior vena cava at 1 and 5 cm below the lowest renal vein in 58 adult trauma patients in pre-resuscitative (hypovolemic) and post-resuscitative (euvolemic) states were assessed in a blinded fashion by two independent readers. Inferior vena cava perimeter, area, and volume were calculated and correlated with caval orientation. Results Mean volumes of the inferior vena cava segment on pre- and post-resuscitation scans were 9.0 cm3 and 11.0 cm3, respectively, with mean percentage increase of 48.6% ( P Conclusions There is significant anisotropic variability of infrarenal inferior vena cava geometry with significantly greater expansive and compressive forces in the minor axis. There can be significant volumetric changes in the inferior vena cava with associated perimeter changes but the major axis left-anterior oblique caval configuration is always maintained. These significant dynamic forces may impact inferior vena cava filter stability after implantation. The consistent major axis left-anterior oblique obliquity may lead to underestimation of the inferior vena cava diameter used in standard anteroposterior venography, which may influence initial filter selection.

To assess the role of CT angiography in the evaluation of patients with lower extremity gunshot wounds in the emergency room. Eighty patients (73 male, 7 female, mean age 26 years) underwent CT angiography for the evaluation of lower extremity gunshot injuries. Imaging was conducted on the basis of standardized protocols utilizing 16-slice and 64-slice multidetector systems and images were qualitatively graded and assessed for various forms of arterial injury. CT angiography findings indicative of arterial injury were observed in 24 patients (30 %) and a total of 43 arterial injuries were noted; the most common form was focal narrowing/spasm (n = 16, 37.2 %); the most common artery involved was the superficial femoral artery (n = 12, 50 %). In qualitative assessment of images based on a 4-point grading system, both readers considered CT angiography diagnostically excellent (grade 4) in most cases. Surgical findings were consistent with CT angiography and follow-up of patients’ medical records showed no arterial injuries in patients with normal findings on initial imaging. Our findings demonstrate that CT angiography is an effective imaging modality for evaluation of lower extremity gunshot wounds and could help limit more invasive procedures such as catheter angiography to a select group of patients. • CT angiography efficiently evaluates lower extremity gunshot wounds. • CT angiography provides image quality sufficiently reliable for assessment of gunshot injuries. • CT angiography could help limit invasive procedures to select patients.

The increase in radiation exposure due to CT scans has been of growing concern in recent years. CT scanners differ in their capabilities, and various indications require unique protocols, but there remains room for standardization and optimization. In this paper, the authors summarize approaches to reduce dose, as discussed in lectures constituting the first session of the 2013 UCSF Virtual Symposium on Radiation Safety and Computed Tomography. The experience of scanning at low dose in different body regions, for both diagnostic and interventional CT procedures, is addressed. An essential primary step is justifying the medical need for each scan. General guiding principles for reducing dose include tailoring a scan to a patient, minimizing scan length, use of tube current modulation and minimizing tube current, minimizing tube potential, iterative reconstruction, and periodic review of CT studies. Organized efforts for standardization have been spearheaded by professional societies such as the American Association of Physicists in Medicine. Finally, all team members should demonstrate an awareness of the importance of minimizing dose.

Lung cancer is the leading cause of cancer-related deaths worldwide, with a dismal 5-year survival rate of 15%. The TNM (tumor-node-metastasis) classification system for lung cancer is a vital guide for determining treatment and prognosis. Despite the importance of accuracy in lung cancer staging, however, correct staging remains a challenging task for many radiologists. The new 7th edition of the TNM classification system features a number of revisions, including subdivision of tumor categories on the basis of size, differentiation between local intrathoracic and distant metastatic disease, recategorization of malignant pleural or pericardial disease from stage III to stage IV, reclassification of separate tumor nodules in the same lung and lobe as the primary tumor from T4 to T3, and reclassification of separate tumor nodules in the same lung but not the same lobe as the primary tumor from M1 to T4. Radiologists must understand the details set forth in the TNM classification system and be familiar with the changes in the 7th edition, which attempts to better correlate disease with prognostic value and treatment strategy. By recognizing the relevant radiologic appearances of lung cancer, understanding the appropriateness of staging disease with the TNM classification system, and being familiar with potential imaging pitfalls, radiologists can make a significant contribution to treatment and outcome in patients with lung cancer.

We compared coronary dual-source computed tomography angiography (corDSCTA) with technetium-99m single-photon emission computed tomography (SPECT) for the detection of myocardial perfusion abnormalities. Fifty-five consecutive patients underwent both gated myocardial perfusion SPECT and corDSCTA, the latter during a single arterial-phase injection of contrast agent. The perfusion defects visualised by corDSCTA correlated with the findings of rest/stress SPECT. Abnormal findings on stress SPECT, which were due to either ischaemia or infarct, were found in 24 patients. In comparison to SPECT at rest, corDSCTA detected perfusion defects with a sensitivity and specificity of 100% and 78%, respectively. Compared to SPECT at stress, the sensitivity and specificity values of corDSCTA were 83.3% and 90.3%, respectively. On corDSCTA , the average attenuation values of perfusion defects that corresponded to chronic infarcts (-8.5+/-22.2 HU) were significantly lower (p = 0.002) than those of non-infarct-related perfusion defects (43.1+/-17.5 HU). Using rest/stress SPECT is the gold standard for the diagnosis of myocardial ischaemia, corDSCTA was able to diagnose ischaemic disease (defined as the presence of high-grade stenotic CAD (or=50% luminal narrowing)) with a sensitivity and specificity of 59% and 89%, respectively, in patients with no known history of myocardial infarction (n = 4). Thus, corDSCTA may serve as a diagnostic tool for the detection of perfusion abnormalities (first) visualised by SPECT. There appears to be a limited correlation between coronary stenotic disease and SPECT findings.

To determine the potential role of dynamic temporally resolved three dimensional (3D) contrast-enhanced magnetic resonance angiography (MRA) for quantitative evaluation of pulmonary perfusion in adult patients with surgically treated Tetralogy of Fallot (ToF).Institutional review board approval and written informed consent were obtained for this Health Insurance Portability and Accountability Act-compliant study. Thirty consecutive patients with surgically repaired ToF and 30 age-matched controls underwent breath-hold 3D time-resolved MRA (TR-MRA) and single-phase high-resolution 3D MRA of the thorax at 1.5 T. Two readers evaluated both datasets for image quality and findings. On TR-MRA datasets, regions-of-interest were placed over main pulmonary artery and lung fields obtaining signal intensity time curves. Using analytic software, time-to-peak (TTP), mean transit time (MTT), maximal signal intensity (MSI), maximum upslope of the curve (MUS), pulmonary blood volume (PBV), and pulmonary blood flow (PBF) were calculated. Pulmonary radionuclide scintigraphy was available for a subgroup of patients with ToF (n = 12).For ToF patients with unilateral pulmonary artery (PA) stenosis, TTP, and MTT were significantly longer, and MSI, MUS, PBV, and PBF were significantly lower in the ipsilateral lung compared with control subjects (P0.001 for all). There was no significant difference in TTP, MTT, MSI, MUS, PBV, and PBF between ToF patients without postsurgical stenotic residua and control subjects (P0.05 for all), nor between the mentioned perfusion indices for the contralateral lung in ToF patients with unilateral PA stenosis and control subjects (P0.05 for all). In ToF, patient with unilateral PA stenosis, analysis of contralateral-to-ipsilateral lung perfusion ratios on radionuclide scintigraphy and TR-MRA revealed significant correlation (r = 0.96). Bland-Altman plot showed a mean difference of 2.2% between the measured ratios (limits of agreement; -7.6%-12.0%).Time-resolved 3D contrast-enhanced MRA has potential for noninvasive and quantitative assessment of altered patterns of pulmonary perfusion in adult ToF, and may be a reliable technique for evaluation of postsurgical residua in these patients.

Aim To evaluate the effectiveness of low-dose, contrast-enhanced, time-resolved, three-dimensional (3D) magnetic resonance (MR) angiography (TR-MRA) in the assessment of various cardiac and vascular diseases, and to compare the results with high-resolution contrast-enhanced MRA (CE-MRA). Materials and Methods Thirty consecutive patients underwent contrast-enhanced 3D TR-MRA and high spatial resolution 3D CE-MRA for evaluation of cardiac and thoracic vascular diseases at 1.5 T, and neurovascular, abdominal and peripheral vascular diseases at 3 T. Gadolinium-based contrast medium was administered at a constant dose of 5 ml for TR-MRA, and 20 ml (lower extremity 30 ml) for CE-MRA. Two readers evaluated image quality using a four-point scale (from 0 = excellent to 3 = non-diagnostic), artefacts and findings on both datasets. Interobserver variability was tested with kappa coefficient. Results The overall image quality for TR-MRA was in the diagnostic range (median 0, range 0–1; k = 0.74). Readers demonstrated important additional dynamic information on TR-MRA in 28 of 30 patients (k = 0.84). Confident evaluation of organ perfusion ( n = 23), arteriovenous malformation/fistula flow patterns ( n = 7), exclusion of intra-cardiac shunts ( n = 6), and assessment of stent and conduit patency ( n = 5) were performed by both readers using TR-MRA. Readers demonstrated fine vascular details with higher confidence in 10 patients on CE-MRA. Using CE-MRA, Reader 1 and 2 depicted anatomical details in 6 and 5 patients, respectively, only on CE-MRA. Conclusion Low-dose TR-MRA yields rapid and important functional and anatomical information in patients with cardiac and vascular diseases. Due to limited spatial resolution, TR-MRA is inferior to CE-MRA in demonstrating fine vascular details.

The purpose of this study was to evaluate the feasibility and reliability of software-based quantification of left ventricular function using 64-slice CT coronary angiography. Data were collected from 26 subjects who underwent a 64-slice coronary CT angiography study. Two volumetric data sets at end diastole and end systole were reconstructed from each scan by means of retrospective electrocardiogram gating. Data sets were evaluated with a prototype of now commercially available software (Syngo Circulation I; Siemens Medical Solutions, Erlangen, Germany), which automatically segments the blood volume in the left ventricle after the user defines the mitral valve plane and any point within the ventricle. After segmentation of the blood pool in end systole and end diastole, the software automatically measures end systolic and end diastolic volume and calculates stroke volume and ejection fraction (EF). Two readers processed all CT data sets twice to assess for intra- and inter-observer variation. In addition, CT EF measurements were compared with those obtained by clinical echocardiography. Intra-observer variation for the calculated EF with CT were 13.6% and 15.6% for Readers 1 and 2, respectively. No significant difference in left ventricular functional parameters on CT existed between the readers (p0.05). A Bland-Altman plot revealed a slight mean difference between EF measurements on CT and echocardiography, with all differences falling within two standard deviations of the mean in the setting of wide limits of agreement. In conclusion, assessment of left ventricular EF from CT coronary data using the new analysis software is rapid and easy. The software is user-friendly and provides good reproducibility for EF measurements with CT.

Detection of a thyroid nodule, either incidental or as a result of related symptomatology, is an extremely common event, often inducing considerable uncertainty regarding the requirement for and best means of further investigation. Whereas tissue sampling represents the sole means of true characterization of these lesions, a number of imaging characteristics have been suggested as potential indicators of the presence of malignancy. The potential value of time-resolved MR angiography, whereby a minimal dose of i.v. contrast agent is dynamically depicted during the first pass of the bolus through the various compartments of circulation, has recently been realized, particularly so with regard to supraaortic angiography. However, it is not uncommon during such temporal imaging to identify focal hyperenhancing thyroid nodules, the significance of which has not previously been described in the literature. We describe the frequency of occurrence and potential significance of this finding, using pathologic correlation where available.The prevalence of malignancy in incidentally detected focal hyperenhancing thyroid parenchymal nodules during time-resolved MR angiography is significant, representing 8.3% (1/12) of patients for whom cytologic correlation was available. Further investigation is certainly warranted when encountering such a lesion in clinical practice, particularly because it appears as though time-resolved MR angiography is of no value in the pathologic discrimination of such incidentally identified lesions.

The purpose of our study was to evaluate the use of preoperative MR angiography of the lower extremities at 3 T in candidates for fibular free flap harvesting, identifying atherosclerotic occlusive disease and congenital anomalies in this population. Our intention was to document the influence of the imaging findings on the surgical approach used.Twenty-nine consecutive adult patients with facial abnormalities necessitating mandibular resection with subsequent osteocutaneous mandibular reconstruction who underwent preoperative MR angiography at 3 T were retrospectively reviewed. Images were evaluated by two observers with regard to image quality and visualization of arterial segments; severity of stenosis; and presence of noise, artifact, or venous contamination. The popliteal artery branching pattern present was also classified. The facial and reconstructive surgeon involved indicated whether the MR angiographic appearances influenced the decision regarding the side or location from which the flap was harvested or the flap design.Arterial segments were visualized with good or excellent image quality in 722 of 725 segments for observer 1 and 721 segments for observer 2. The kappa coefficient indicated good interobserver agreement (kappa = 0.78) with regard to quality of arterial segment depiction and scoring of stenoocclusive disease (kappa = 0.64). No segments had venous contamination, noise, or artifact of a degree sufficient to compromise diagnostic interpretation. Imaging influenced the surgical approach in 16 (55.2%) of 29 patients.Trifurcation vessel imaging should be a prerequisite to fibular free flap harvesting. High-spatial-resolution MR angiography at 3 T represents a desirable alternative to other invasive or cross-sectional imaging techniques in this regard.

A number of clinical situations exist in which high-resolution depiction of the external carotid artery system is required, a task not previously addressed by MR angiography. The purpose of this study was to evaluate the extent to which high-spatial-resolution MR angiography at 3 T can be used to map the normal external carotid artery system.Twenty-three consenting adult patients were prospectively evaluated. Images acquired were evaluated by two independent observers, and each branch vessel was scored with regard to image quality, presence and grade of stenoses, and artifacts. Interobserver agreement regarding image quality and the presence and degree of stenosis was tested using the kappa coefficient. Differences in quality ratings between the two observers were assessed using the paired Student's t test.Of 828 vessels analyzed, 92.63% were designated of diagnostic quality with no significant difference between the observers' image quality scores (p = 0.63). Good agreement was determined regarding image quality achieved (kappa = 0.716). All examinations were free of artifact sufficient to interfere with confident interpretation. Excellent correlation was seen with regard to stenosis detection and grading (kappa = 0.857). Of the external carotid artery systems assessed, 82.6% showed conventional anatomic vascular branching.High-spatial-resolution, 3D contrast-enhanced MR angiography at 3 T using sagittal source data acquisition and an advanced acceleration factor of 6 allows high-quality (92.63% of arterial segments) visualization of the external carotid artery system, with complete head and neck vascular coverage.

To assess the incremental diagnostic value of time-resolved three-dimensional (3D) magnetic resonance (MR) angiography over single-phase 3D MR angiography and cine MR imaging in juvenile and adult patients with congenital heart disease (CHD).The study was HIPAA compliant and was approved by the institutional review board. Written informed consent was obtained from each patient. Eighty-one consecutive patients (46 male and 35 female patients; mean age, 31.1 years +/- 13.5 [standard deviation]) with CHD were examined with a 1.5-T MR imaging unit. The imaging protocol comprised time-resolved MR angiography (repetition time msec/echo time msec, 2.01/0.81) after injection of 0.03 mmol gadodiamide per kilogram of body weight at 4 mL/sec and single-phase high-spatial-resolution MR angiography (2.87/0.97) after injection of 0.15 mmol/kg gadodiamide at 1.5 mL/sec. After review of the time-resolved and conventional MR angiographic data sets, each of two independent observers listed the additional clinical information gained from time-resolved MR angiographic data. A Wilcoxon signed rank test was used to test for statistical differences between the image quality ratings of the two observers.Time-resolved and single-phase high-spatial-resolution MR angiography yielded diagnostic image data in all patients. Observers 1 and 2 found functional information in time-resolved MR angiographic series in 52 and 51 patients, respectively, that was not seen at high-spatial-resolution MR angiography. Intra- and extracardiac shunts, respectively, were exclusively depicted by time-resolved MR angiography for observer 1 in 18 and two patients and for observer 2 in 15 and two patients. However, both observers reported higher confidence in the assessment of such smaller vascular structures as supraaortic vessels (in 12 patients for observer 1 and 11 patients for observer 2) and major aortopulmonary collateral arteries (in eight patients for observer 1 and 10 patients for observer 2) at high-spatial-resolution MR angiography. No significant difference was evident in image quality scoring between the two observers (P = .32 for time-resolved and P = .47 for conventional MR angiography).Compared with conventional MR angiography, time-resolved MR angiography yields clinically relevant information in a substantial number of patients; hence, the two techniques should be regarded as complementary.

Objectives Quantitative assessment of left ventricular (LV) functional parameters in cardiac MR requires time-consuming contour tracing across multiple short axis images. This study assesses global LV functional parameters using 3-slice segmentation on steady state free precision (SSFP) cine short axis images and compares the results with conventional multi-slice segmentation of LV. Methods Data were collected from 61 patients who underwent cardiac MRI for various clinical indications. Semi-automated cardiac MR software was used to trace LV contours both at multiple slices from base to apex as well as just 3 slices (base, mid, and apical) by two readers. Left ventricular ejection fraction (LVEF), LV volumes, and LV mass were calculated using both methods. Results Bland–Altman plot revealed narrow limits of agreement (−4.4% to 5.1%) between LVEF obtained by the two methods. Bland–Altman analysis showed slightly wider limits of agreement between end-diastolic volumes (−5.0 to 12.0%; −3.9 to 8.5ml/m 2 ), end-systolic volumes (−10.9 to 14.7%; −4.1 to 6.5ml/m 2 ), and LV mass (−5.2 to 12.7%; −4.8 to 10.2g/m 2 ) obtained by the two methods. There was a small mean difference between LV volumes and LV mass obtained using multi-slice and 3-slice segmentation. No statistically significant difference existed between the LV parameters obtained by the two readers using 3-slice segmentation ( p >0.05). Multi-slice assessment required approximately 15min per study while 3-slice assessment required less than 5min. Conclusions 3-slice segmentation of the left ventricle at basal, mid, and apical levels on cine SSFP short axis images can provide rapid and reliable assessment of LVEF with good reproducibility. The 3-slice method also provides a reasonable estimate of the LV volumes and LV mass.

The objective of this study was to identify if bacteraemias occur during sialography, which could predispose to endocarditis in susceptible patients. Patients requiring sialography who gave informed consent were included in the trial. Patients taking antibiotics, or who were predisposed to infective endocarditis, were excluded. Sialography was performed using a standard hand injection technique with a water-soluble non-ionic contrast agent (Niopam, Bracco, UK). An indwelling cannula was inserted into the forearm prior to the procedure and then three blood samples of at least 10 ml were taken: sample one before sialography; sample two was taken as a continuous withdrawal during the sialographic procedure; and sample three over a further 10 min period after sialography. The blood samples were cultured for bacteria using the BacT/ALERT system (BioMerieux, UK). 32 patients were included in the study. No samples showed evidence of bacteraemia. Three patients had bacterial contamination from skin commensals. Using the rule of three, we have shown a 95% confidence interval of 3/32 = 0.09. In conclusion, the results of this study suggest that sialography is not associated with bacteraemia.

CT-guided percutaneous adrenal biopsy is commonly performed using a posterior or trans-abdominal approach. However, trans-abdominal access to the gland may not be technically feasible in some patients. In our case, CT-guided transthoracic percutaneous biopsy of the adrenal gland was performed with technical success, identifying the tumour. To the best of our knowledge, there has been no previous case describing this transpulmonary approach in the literature.

Intramural esophageal dissection (IED) is a rare but important condition to differentiate from a through perforation. We describe an interesting case in which multi-slice spiral computed tomography of the thorax was obtained immediately after the contrast swallow, to demonstrate features of intramural esophageal dissection. To the best of our knowledge, these CT appearances of intramural esophageal dissection have not yet been reported in the literature.

To assess the feasibility of a fast single-bolus combined carotid and coronary computed tomography angiography (CTA) protocol in asymptomatic patients.Thirty-three consecutive patients (18 women and 15 men) with a median age of 61 ± 14 years old (range 37-87 years) with known or suspected atherosclerotic disease were enrolled in this prospective study. A single breath-hold, single biphasic injection protocol (50 ml at 3 ml/s, 50 ml at 5 ml/s, 50 ml saline flush at 5 ml/s) was used for combined CTA imaging of the supra-aortic (SAA) and coronary arteries (CA) on a 64-slice dual-source CT (DSCT) machine. Helical CTA acquisition of the SAA was followed by prospective electrocardiography (ECG)-triggered coronary CTA. Subjective (four-point scale) image quality and objective signal-to-noise (SNR) and contrast-to-noise (CNR) measurements were performed. Vascular disease was graded on a four-point scale (grade 1: absent; grade 2: mild, grade 3: moderate; grade 4: severe). The radiation dose was recorded for each patient.The average enhancement and subjective quality score of SAA and CA segments were 396 HU/358 HU and 1.2 ± 0.3/1.72 ± 0.4, respectively. The SNR was 27.1 ± 1.7 in the SAA and 21.6 ± 1.6 in the CA (p0.0001). The CNR was 18.1 ± 1.2 and 15.9 ± 1.8, respectively (p = 0.4). Four percent of SAA and 14% of CA segments (mostly due to peri-venous streak artefacts and small calibre, respectively) produced non-diagnostic images. SAA findings were as follows: 26/33 (79%) patients showed no disease and 6/33 (18%) had grade 2 and 1/33 (3%) had grade 3 disease. CA findings were as follows: 25/33 (76%) showed no disease and 6/33 (18%) patients had grade 2 and 2/33 (6%) had grade 3 disease. Five patients had disease in both districts. The average radiation dose for the combined CTA angiogram was 4.3 ± 0.6 mSv.A fast, low-dose combined DSCT angiography protocol appears technically feasible for imaging carotid and coronary atherosclerotic disease.

The Centers for Disease Control and Prevention reported more than one million people with HIV infection in the United States in 2006, an increase of 11% over 3 years. Worldwide, nearly 34 million people are infected with HIV. Pulmonary disease accounts for 30-40% of acute hospitalizations of HIV-seropositive patients, underscoring the importance of understanding the range of cardiothoracic imaging findings associated with HIV infection. This article will cover extrapulmonary thoracic diseases, chronic lung diseases, and immune reconstitution inflammatory syndrome in HIV-infected patients. Our approach is focused on the radiologist's perspective by recognizing and categorizing key imaging findings to generate a differential diagnosis. The differential diagnosis can be further refined by incorporating clinical data, such as patient demographics, CD4 count, and presenting symptoms. In addition, with prolonged survival of HIV-infected patients in the era of highly active antiretroviral therapy, radiologists can also benefit from awareness of imaging features of a myriad of chronic cardiopulmonary diseases in this patient population. Finally, the change of imaging findings and clinical status in response to treatment provides important diagnostic information, such as in immune reconstitution syndrome.Developing a practical approach to key cardiothoracic imaging findings in HIV-infected patients will aid the radiologist in generating a clinically relevant differential diagnosis and interpretation, thereby improving patient care.

The Centers for Disease Control and Prevention reported more than one million people with HIV infection in the United States in 2006, an increase of 11% over 3 years. Worldwide, nearly 34 million people are infected with HIV. Pulmonary disease accounts for 30-40% of acute hospitalizations of HIV-infected patients, underscoring the importance of understanding the pulmonary manifestations in this population. When presented with a chest radiograph or CT image of a patient with the clinical history of HIV infection, one approach is to start by identifying and categorizing key imaging findings. In some instances, the key findings may be further subcategorized to narrow the differential diagnosis, such as distinguishing between perilymphatic distribution and the random distribution of micronodules. The differential diagnosis of these key imaging findings can also be further refined by incorporating clinical data, such as patient demographics, CD4 count, and presenting symptoms. Finally, the change of thoracic disease and clinical status in response to treatment provides important diagnostic information. The purpose of this article is to discuss pulmonary findings in patients with HIV.By developing a systematic and practical approach to key pulmonary imaging findings in HIV-infected patients, radiologists can generate clinically relevant and succinct differential diagnoses and thereby improve patient care.

Purpose To assess cardiothoracic structure and function in patients with pectus excavatum compared with control subjects using cardiovascular magnetic resonance imaging (CMR). Method Thirty patients with pectus excavatum deformity (23 men, 7 women, age range: 14-67 years) underwent CMR using 1.5-Tesla scanner (Siemens) and were compared to 25 healthy controls (18 men, 7 women, age range 18-50 years). The CMR protocol included cardiac cine images, pulmonary artery flow quantification, time resolved 3D contrast enhanced MR angiography (CEMRA) and high spatial resolution CEMRA. Chest wall indices including maximum transverse diameter, pectus index (PI), and chest-flatness were measured in all subjects. Left and right ventricular ejection fractions (LVEF, RVEF), ventricular long and short dimensions (LD, SD), mid-ventricle myocardial shortening, pulmonary-systemic circulation time, and pulmonary artery flow were quantified. Results In patients with pectus excavatum, the pectus index was 9.3 ± 5.0 versus 2.8 ± 0.4 in controls (P < 0.001). No significant differences between pectus excavatum patients and controls were found in LV ejection fraction, LV myocardial shortening, pulmonary-systemic circulation time or pulmonary flow indices. In pectus excavatum, resting RV ejection fraction was reduced (53.9 ± 9.6 versus 60.5 ± 9.5; P = 0.013), RVSD was reduced (P < 0.05) both at end diastole and systole, RVLD was increased at end diastole (P < 0.05) reflecting geometric distortion of the RV due to sternal compression. Conclusion Depression of the sternum in pectus excavatum patients distorts RV geometry. Resting RVEF was reduced by 6% of the control value, suggesting that these geometrical changes may influence myocardial performance. Resting LV function, pulmonary circulation times and pulmonary vascular anatomy and perfusion indices were no different to controls.

Cardiac paragangliomas are among the rarest primary cardiac tumors. We present a case of left atrial paraganglioma in a patient who presented with symptoms and signs of catecholamine excess in which cardiovascular magnetic resonance in multiple orientations and PET-CT played an important role in the diagnosis and tissue characterization.

A 12-year-old boy presented with hypertension and intermittent lower extremity claudication. Breath-hold high spatial resolution MRA at 3.0 T (gradient recalled echo sequence; 10 ml of Magnevist) revealed abdominal aortic coarctation (Fig. 1, thin long arrow), severely narrowed right renal artery and atrophy of the ipsilateral kidney (Fig. 1b, arrowhead), and hypertrophied inferior mesenteric artery (Fig. 1a, thick short arrow) feeding the superior mesenteric artery (Fig. 1a, thin short arrow) through the arc of Riolan (Fig. 1a, arrowhead). The child had previously undergone placement of an aorto-aortic graft (Fig. 1, thick long arrow). Fig. 1 3-D volume-rendered MR angiograms (Vitrea 3.6; Vital Images, Minneapolis, MN) Midaortic syndrome (MAS) is a rare disease caused by segmental narrowing of the abdominal or distal descending thoracic aorta associated with concomitant stenoses involving the renal (63%) and visceral (33%) arteries [1]. MAS can be congenital or acquired caused by giant cell or Takayasu arteritis, retroperitoneal fibrosis, Williams syndrome, fibromuscular dysplasia, neurofibromatosis, and mucopolysaccharidosis [1, 2]. Noninvasive diagnosis is made by MRA or CT angiography [2]. Surgical bypass grafting is the optimal method of treatment [1].

Objectives: The purpose of this study was to determine the image quality and diagnostic accuracy of three-dimensional (3D) unenhanced steady state free precession (SSFP) magnetic resonance angiography (MRA) for the evaluation of thoracic aortic diseases. Methods: Fifty consecutive patients with known or suspected thoracic aortic disease underwent free-breathing ECG-gated unenhanced SSFP MRA with non-selective radiofrequency excitation and contrast-enhanced (CE) MRA of the thorax at 1.5T. Two readers independently evaluated the two datasets for image quality in the aortic root, ascending aorta, aortic arch, descending aorta, and origins of supra-aortic arteries, and for abnormal findings. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were determined for both datasets. Sensitivity, specificity, and diagnostic accuracy of unenhanced SSFP MRA for the diagnosis of aortic abnormalities were determined. Results: Abnormal aortic findings, including aneurysm (n=47), coarctation (n=14), dissection (n=12), aortic graft (n=6), intramural hematoma (n=11), mural thrombus in the aortic arch (n=1), and penetrating aortic ulcer (n=9), were confidently detected on both datasets. Sensitivity, specificity, and diagnostic accuracy of SSFP MRA for the detection of aortic disease were 100% with CE-MRA serving as a reference standard. Image quality of the aortic root was significantly higher on SSFP MRA (P0.05). SNR and CNR values were higher for all segments on SSFP MRA (P

To evaluate the feasibility of 3-dimensional (3D) steady-state free-precession (SSFP) magnetic resonance angiography (MRA) using nonselective radiofrequency excitation for imaging of pulmonary veins (PVs) without intravenous gadolinium chelate and to correlate the results with conventional contrast-enhanced MRA (CE-MRA).Forty consecutive patients with history of atrial fibrillation underwent free-breathing respiratory navigator-gated electrocardiogram-triggered SSFP MRA without contrast administration and conventional high-resolution 3D CE-MRA of the thorax at 1.5 T. Two readers assessed both datasets for vascular definition (from 0, not visualized, to 3, excellent definition), artifacts, and ostial diameters. Statistical analysis was performed using Wilcoxon, paired t test, and kappa coefficient.On SSFP MRA, readers 1 and 2 graded 96.4% (160/166) and 97% (161/166) of the segments as having diagnostic visibility and sharpness, respectively (k = 0.82). On CE-MRA datasets, all segments were graded as having diagnostic visibility and sharpness by both readers (k = 0.86). No significant difference existed for visibility and sharpness of pulmonary venous segments between the datasets for each reader (P[r]0.05). Reader 1 (2) identified 27 (28) and 35 (32) motion artifacts on SSFP and CE-MRA datasets, respectively. No significant difference was found to exist between ostial diameters on CE-MRA and SSFP datasets (P0.05).Our study shows that 3D depiction of PVs without intravenous contrast is feasible with nonslice-selective SSFP MRA. This novel MRA technique may be used in certain patients with atrial fibrillation to assess the number and size of PV ostia draining to the left atrium prior to radiofrequency ablation.

The objective of our study was to assess the feasibility and diagnostic performance of time-resolved MR angiography (MRA) in the evaluation of central thoracic venous occlusive disease and to compare time-resolved MRA with conventional MRA and catheter angiography.Twenty patients (eight women and 12 men; age range, 19-74 years) with suspected central thoracic venous occlusive disease underwent time-resolved MRA using time-resolved angiography with interleaved stochastic trajectories (TWIST) and parallel acquisition, followed by conventional MRA. Catheter angiography was performed within 1-14 days after MRA and was available for a total of 60 segments for correlation. Time-resolved and conventional MRA images were evaluated in separate reading sessions by two independent radiologists for image quality and level of confidence and degree of venoocclusive disease. The interobserver and intermodality agreement, sensitivity, and specificity were calculated using catheter angiography as the standard of reference.Time-resolved MRA resulted in diagnostic-quality images that did not differ significantly in quality compared with conventional MRA. Thirty-one segmental venous stenoses were identified. The kappa coefficient revealed moderate intermodality agreement (kappa = 0.54; 95% CI, 0.32-0.76) between time-resolved MRA and conventional MRA. When compared with catheter angiography, the sensitivity and specificity for the diagnosis of significant stenosis (or = 70%) were 87.5% and 68% for time-resolved MRA and 90% and 90% for conventional MRA, respectively.Time-resolved MRA, as described in this study, has the potential to be used as an initial and screening diagnostic tool obviating conventional MRA and its associated higher contrast dose in normal and near-normal examinations. However, because of its relatively lower specificity, adjunct use of conventional MRA is still required for accurate grading of venous occlusive disease.

Purpose To determine whether time-resolved magnetic resonance angiography (TR-MRA) with ultra-low-dose gadolinium chelate (1.5-3.0 mL) can reliably detect or rule out hemodynamically significant disease in the carotid-vertebral artery territory. Materials and methods Hundred consecutive patients (62 women, 38 men, mean age = 56.6 years) underwent both TR-MRA and standard high-resolution contrast-enhanced magnetic resonance angiography (CE-MRA), having been randomized to 1 of 2 groups; group A receiving a contrast dose of 1.5 mL for TR-MRA and group B receiving 3.0 mL. For scoring purposes the arterial system was divided into 21 segments. All TR-MRA and CE-MRA studies were blindly assessed by 2 radiologists for overall image quality, segmental arterial visualization, grading of arterial stenosis/occlusion, and incidence and severity of artifact. TR-MRA findings were directly compared with those of the corresponding CE-MRA examinations. Results Group A TR-MRA studies were of significantly inferior overall image quality compared with those of the corresponding CE-MRA examinations (P = 0.01 for both observers). In group B, overall image quality was similar for TR-MRA and single-phase CE-MRA examinations. On a segmental basis, a higher number of "insufficient quality" segments were identified in group A TR-MRA studies than in group B. A similar reduction in the incidence of artifacts was observed for group B relative to group A TR-MRA studies. Both groups A and B TR-MRA studies were of high specificity, negative predictive values, and accuracy (>97%). Conclusion Ultra-low dose TR-MRA may be performed with 3 mL of gadolinium chelate with preservation of overall image quality and arterial segmental visualization relative to single phase CE-MRA, whereas a 1.5 mL contrast dose is associated with more suboptimal studies. Nonetheless, even at doses as low as 1.5 mL, TR-MRA can exclude arterial stenosis or occlusion.

BACKGROUND AND PURPOSE: The effect of various contrast-dose regimens for cerebral MR venography (MRV) has not been previously evaluated at 3T, to our knowledge. Our purpose was to evaluate and compare the diagnostic image quality resulting from half-versus-full-dose contrast regimens for high-spatial-resolution 3D cerebral MRV at 3T. MATERIALS AND METHODS: Forty consecutive patients with known or suggested cerebrovascular disease underwent 3D high-spatial-resolution (0.7 × 0.6 × 0.9 mm(3)) cerebral contrast-enhanced MRV (CE-MRV) at 3T, by using an identical acquisition protocol. Patients were assigned to 1 of 2 groups: 1) full-dose (∼0.1 mmol/kg), and 2) half-dose (∼0.05 mmol/kg). Two readers evaluated the resulting images for overall image quality, venous structure definition, and arterial contamination. Signal intensity–to-noise-ratio (SNR) and contrast-to-noise-ratio (CNR) were evaluated in 8 consistent sites. Statistical analysis was performed by using Mann-Whitney U, Wilcoxon signed rank, and t tests and a κ coefficient. RESULTS: Both readers scored venous-structure definition as excellent or sufficient for diagnosis in approximately 90% of segments for the full-dose group (κ = 0.87) and in approximately 80% of segments for the half-dose group (κ = 0.85). Delineation grades were significantly lower for small venous segments, including the middle cerebral, septal, superior cerebellar, inferior vermian, posterior tonsillar, and thalamostriate veins in the half-dose group (P < .01). No significant difference existed for arterial contamination grades between the 2 groups (P > .05). SNR and CNR values were lower in the half-dose group (P < .01). CONCLUSIONS: At 3T, high-spatial-resolution cerebral MRV can be performed with contrast doses as low as 7.5 mL, without compromising image quality as compared with full-dose protocols, except in the smallest veins, and without compromise of acquisition speed or spatial resolution.

Coronary artery fistula is a rare vascular anomaly in which there is abnormal communication between the coronary artery and the great vessels or cardiac chambers. We report the case of a 66-year-old man with two separate coronary artery to pulmonary artery fistulas (one of which demonstrated multiple aneurysms), which were diagnosed on dual-source 64-slice coronary CT and reconfirmed by coronary catheter angiography.

Continued advances in radiofrequency hardware and tailored software have, in recent times, greatly increased the power and performance of magnetic resonance imaging for noninvasive evaluation of cardiovascular diseases. Magnetic resonance imaging can uniquely be manipulated to trade temporal resolution and spatial resolution against each other, depending on whether detailed structural or functional information is required. However, to date, a number of cardiovascular magnetic resonance applications have been somewhat limited due to signal-to-noise ratio constraints, reflecting the narrow imaging window imposed by physiological cardiac motion. By increasing the operating field strength from 1.5 to 3 T, it is possible (in principle) to double the signal-to-noise ratio, which in turn may be "traded" for improvements in spatial resolution, coverage, or imaging speed. In this context, the development of parallel imaging has set the stage for impressive performance improvements in contrast-enhanced magnetic resonance angiography at 3 T. Indeed, one could argue that without parallel acquisition, the bang for the buck in going from 1.5 to 3 T would be limited. In this paper, we discuss the current status of 3-T magnetic resonance imaging for cardiovascular imaging, considering the relative gains and limitations relative to 1.5 T.

To determine whether contrast material dose reduction at 3.0 T allows preserved image quality for high-spatial-resolution magnetic resonance (MR) angiography of the lower extremities.Forty-five consecutive patients (27 men, 18 women; mean age, 64 years) underwent contrast material-enhanced MR angiography of the lower extremities at 3.0 T. A waiver of informed consent was granted by the institutional review board. Sixteen patients received high-dose (approximately 0.3 mmol/kg), 15 received intermediate-dose (approximately 0.2 mmol/kg), and 14 received low-dose (approximately 0.1 mmol/kg) gadopentetate dimeglumine during a three-station, dual-injection examination. For scoring purposes, the arterial system from the celiac trunk to the plantar arteries was divided into 34 segments. The images were retrospectively and independently evaluated by two specialized radiologists who were blinded to the patient dose groups. All studies were assessed for overall image quality and the degree of contaminating venous enhancement. Each arterial segment was scored for the quality of vessel definition, the severity of stenoses, and the presence of collateral vessels.More than 99% of arterial segments were found to be of diagnostic image quality by both readers in all dose groups. Generalized estimating equation analysis showed a significant difference among the three groups with regard to vessel definition (P = .019). No significant difference was found between the high- and intermediate-dose groups; however, the low-dose group had significantly better vessel definition compared with the high-dose (P = .034) and intermediate-dose (P = .015) groups. There was no significant difference among the groups in visualization of collateral vessels. Venous contamination was seen less frequently in the low-dose group, but the difference did not achieve significance.The study showed that, compared with widely used dose strategies at 1.5 T, the contrast agent dose for 3.0-T lower extremity MR angiography can be reduced multifold without compromising image quality.

To investigate a high spatial resolution peripheral contrast-enhanced MR angiography (CE-MRA) protocol, applying a dedicated multi-channel array coil and accelerated parallel acquisition at 3.0T in evaluation of patients with peripheral vascular disease. Twenty patients with peripheral vascular disease underwent multi-station high spatial resolution peripheral CE-MRA at 3T. The image quality, presence of venous contamination, image noise, and artifact were evaluated by 2 radiologists independently. Assessment of arterial disease for 540 arterial segments was performed, and findings were correlated with conventional catheter angiography in 10 patients. All studies were yielded high diagnostic image quality. Venous contamination and artifact were minimal and never interfered with diagnosis. Sixty seven arterial segments with significant stenoses (0%) were detected by observers with excellent interobserver agreement (kappa = 0.82; 95% CI: 0.76, 0.88). There was a significant correlation between CE-MRA and conventional angiography (Rs = 0.91 and 0.94 for reader 1 and 2, respectively) for the assessment of the degree of stenosis. Higher available SNR at 3T in combination with multi-coil technology and accelerated parallel acquisition, result in acquisition of nearly isotropic submillimeter 3D voxels throughout the entire peripheral arterial tree with diagnostic image quality and favorable comparative analysis with catheter angiography.

To evaluate the feasibility of three-dimensional (3D) steady-state free-precession (SSFP) magnetic resonance angiography (MRA) using nonselective radiofrequency excitation in the assessment of cardiac morphology, thoracic aorta, main pulmonary, and proximal coronary arteries.Thirty consecutive patients (19 males; 11 females; age range, 20-74) with various cardiac and thoracic vascular diseases underwent free-breathing respiratory navigator-gated electrocardiogram-triggered noncontrast SSFP MRA and conventional high-resolution 3D contrast-enhanced MRA (CE-MRA) of the thorax at 1.5 T. Two readers evaluated both datasets for findings, vascular delineation and sharpness (from 0, not visualized to 3, excellent definition), artifacts, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) in 14 vascular segments including aorta, supra-aortic, pulmonary, and coronary arteries, and in cardiac chambers. Statistical analysis was performed using Wilcoxon test for vessel delineation, and [kappa] coefficient for interobserver variability.3D SSFP and CE-MRA were successfully performed in all patients. Scan time for SSFP MRA ranged from 5 to 10 minutes (mean +/- standard deviation, 7 +/- 2 minutes). On SSFP MRA, readers 1 and 2 graded 233 (97.1%) and 234 (97.5%) coronary arterial segments and cardiac chambers, and 275 (91.7%) and 278 (92.7%) noncoronary arterial segments with diagnostic definition (grades 2 and 3) (k = 0.86). On conventional CE-MRA, readers 1 and 2 graded 10 (4.2%) and 12 (5%) coronary arterial segments and cardiac chambers, and 272 (90.7%) and 270 (90%) noncoronary arterial segments with diagnostic definition (grades 2 and 3) (k = 0.89). Segmental visibility was higher for aortic root, pulmonary trunk, proximal coronary arteries, and heart chambers (P0.001), and lower for supra-aortic arteries (P0.001) on SSFP MRA for each reader. SNR and CNR values were higher for aortic root and aorta on SSFP MRA (P0.001 for both). No significant difference existed between SNR and CNR values for the other vascular segments and cardiac chambers on SSFP and CE-MRA (P0.05 for all). The 2 readers demonstrated vascular stenosis and dilatation/aneurysm in 7 and 35 segments on both datasets, respectively.Noncontrast 3D SSFP MRA with nonselective radiofrequency excitation provides high image quality and sufficient SNR and CNR for confident assessment of cardiac and thoracic vascular diseases including congenital heart diseases. Our results suggest that noncontrast SSFP MRA outperforms CE-MRA in visualization of cardiac chambers, proximal coronary arteries, pulmonary trunk, and aortic root.

Time-resolved magnetic resonance angiography (TR-MRA) has received considerable attention recently owing to its ability to provide a dynamic complement to otherwise "static" high-resolution 3-D contrast-enhanced MRA for a variety of clinical indications. Steady technologic advances, including ultrafast pulse sequences, phased multiarray surface coils, parallel data acquisition techniques, and the widespread availability of high-field magnetic resonance systems, have enhanced the clinical usefulness of TR-MRA. This article considers the current role of TR-MRA in thoracic imaging, illustrating many of its clinical applications, and potential future of this recent approach to noninvasive dynamic vascular evaluation.

To evaluate the feasibility of three-dimensional (3D) steady state free precession (SSFP) magnetic resonance angiography (MRA) using nonselective radiofrequency excitation for the assessment of thoracic central veins.Thirty consecutive patients (17 males, 13 females, age range 22-76) with various cardiac and thoracic vascular diseases underwent free-breathing electrocardiogram-gated noncontrast SSFP MRA and conventional high-resolution 3D contrast-enhanced (CE) MRA of the thorax at 1.5 T. Two readers evaluated both datasets for findings: venous visibility and sharpness (from 0, not visualized to 3, excellent definition); artifacts; signal-to-noise ratio (SNR); and contrast-to-noise ratio (CNR) in 8 venous segments including superior vena cava (SVC), supra-diaphragmatic inferior vena cava, bilateral brachiocephalic, proximal subclavian, and lower internal jugular veins. Statistical analysis was performed using Wilcoxon test for overall image quality and vessel visibility, t test for SNR and CNR analysis, and kappa coefficient for inter-observer variability.3D SSFP and CE-MRA were successfully performed in all patients. Scan time for SSFP MRA ranged from 5 to 10 minutes (mean +/- standard deviation, 7 +/- 2 minutes). Reader 1 (2) graded the overall image quality as excellent and good on SSFP MRA in 23 (25) and 7 (5) patients, and on CE-MRA in 22 (23) and 8 (9) patients, respectively. On SSFP MRA, readers 1 and 2 graded 234 (97.5%) and 233 (97.1%) venous segments with diagnostic definition (grades 2 and 3) (kappa = 0.69), respectively. On conventional CE-MRA, readers 1 and 2 graded 231 (96.3%) and 232 (96.7%) venous segments with diagnostic definition (grades 2 and 3) (kappa = 0.68), respectively. Segmental visibility and sharpness were higher for lower internal jugular veins on CE-MRA for each reader (P0.001). No significant difference existed for venous visibility and sharpness scores for other venous segments between the 2 techniques for both readers (P0.05). SNR and CNR values were lower for internal jugular veins on SSFP MRA (P0.001). No significant difference existed between SNR and CNR values for the other venous segments on SSFP and CE-MRA (P0.05 for all). The 2 readers demonstrated patent SVC Glenn shunt to main pulmonary artery (n = 3), patent extra cardiac Fontan shunt from inferior vena cava to pulmonary artery confluence (n = 2), and dilatation and thrombosis of SVC (n = 1) and right brachiocephalic vein (n = 1) on both datasets.Free breathing navigator-gated noncontrast 3D SSFP MRA with nonselective radiofrequency excitation provides high image quality and sufficient SNR and CNR for confident evaluation of thoracic central veins.

We present a case of cardiac capillary hemangioma in a patient who presented with a history of recurrent episodes of syncope. Cardiovascular magnetic resonance played an important role in the diagnosis of cardiac hemangioma in our patient.

In the past decade, lung transplantation has become established as an accepted therapy for end-stage pulmonary disease. Complications of lung transplantation that may occur in the immediate or longer postoperative term include mechanical problems due to a size mismatch between the donor lung and the recipient thoracic cage; malposition of monitoring tubes and lines; injuries from ischemia and reperfusion; acute pleural events; hyperacute, acute, and chronic rejection; pulmonary infections; bronchial anastomotic complications; pulmonary thromboembolism; upper-lobe fibrosis; primary disease recurrence; posttransplantation lymphoproliferative disorder; and native lung complications such as hyperinflation, malignancy, and infection. Radiologic imaging--particularly chest radiography, computed tomography (CT), and high-resolution CT--is critical for the early detection, evaluation, and diagnosis of complications after lung transplantation. To enable the selection of an effective and relevant course of therapy and, ultimately, to decrease morbidity and mortality among lung transplant recipients, radiologists at all levels of experience must be able to recognize and understand the imaging manifestations of posttransplantation complications.

The purpose of this HIPAA-compliant study was to prospectively evaluate the technical feasibility of a multistation high-spatial-resolution whole-body magnetic resonance (MR) angiography protocol in which high-acceleration parallel imaging (with acceleration factors of three and four) is performed with a 32-channel 3.0-T MR system. After institutional review board approval and written informed consent were obtained, 10 healthy volunteers (four men and six women aged 23-68 years) and four patients (two men and two women aged 56-79 years) suspected of having peripheral vascular disease underwent multistation whole-body contrast material-enhanced MR angiography. Use of multiarray surface coil technology and highly accelerated generalized autocalibrating partially parallel acquisition enabled the acquisition of isotropic high-spatial-resolution three-dimensional data sets for multiple stations. Two radiologists independently evaluated arterial image quality and presence of arterial stenoses. All examinations yielded good or excellent image quality. Interobserver agreement was excellent (kappa = 0.92; 95% confidence interval: 0.86, 0.96). Multistation whole-body MR angiography with high-acceleration parallel acquisition is feasible at 3.0 T. Further clinical studies combined with ongoing optimization of radiofrequency systems and coils seem warranted to advance the potential of this technology.

A 20-year-old man with no significant past medical history presented with sudden onset of sharp right temporal headache and left-sided weakness. He also noticed some visual disturbance in the left eye. His symptoms lasted about 6 h and then resolved. There was no history of recent trauma or drug abuse. There was a family history of stroke, which had affected his aunt and grandfather. He was normotensive and in sinus rhythm. Cardiovascular examination was normal and neurological examination confirmed a mild left-sided weakness and left facial droop. Unenhanced cranial CT and baseline blood tests were performed on the same day as the event and demonstrated no abnormality. Urgent carotid Doppler US on the following day showed normal Doppler parameters in the left extracranial carotid circulation. However, the right common carotid artery (RCCA) waveform demonstrated flow reversal in early diastole (Fig. 1(a)) when compared with the

were recorded including rates of endoleaks, neurological complication, repeat procedures, and left arm claudication. Results: Median follow up was 552.5 days. LSCA was embolized in 41/104 (39%) of procedures. Indication for TEVAR in the embolized and non-embolized groups was dissection in 23/41 (56%) and 28/63 (44%), aneurysm 11/41 (26%) and 19/63 (30%), pseudoaneurysm 6/41 (14%) and 4/ 64 (6%), transection 1/41 (2%) and 9/64 (14%), and penetrating ulcers 0/41 (0%) and 3/64 (4%), respectively. The cerebrovascular accident (CVA) rate was 7/41 (17%) and 7/63(11%) and paralysis rate was 0/41 (0%) and 1/63 (2%) for the embolized and non-embolized groups respectively. The endoleak rate was 24/41 (58%) for the embolized group; 7/41 (17%) were persistent and resulted in aneurysm sac enlargement (6 type Ia and 1 type II endoleak) treated with sac embolization (n1⁄45), stent graft extension (n1⁄41), or surgical repair (n1⁄41). Endoleak rate was 22/63 (35%) for the non-embolized group; 5/63 (8%) were persistent and resulted in aneurysm sac enlargement (3 type Ia and 2 type II endoleaks) treated with LSCA embolization (n1⁄44) and both LSCA and sac embolization (n1⁄41). LSCA was covered without a carotid-subclavian bypass in 58/104 (56%). CVA rates for bypass and no bypass groups were 5/46 (11%) and 6/58 (10%) and paralysis rates were 1/46 (2%) and 0%, respectively. 10/58 (17%) patients required a subsequent carotid-subclavian bypass for left arm claudication. Conclusion: Coverage of the left subclavian artery during endovascular repair of the thoracic aorta is feasible with low complication rates. Embolization of the LSCA may be required to prevent or treat endoleaks.

We retrospectively studied 1.5T cardiac MR images of 62 patients with various clinical indications. All patients had a stack of EKG gated segmented SSFP cine images through the LV. Semi-automated cardiac MR software (Argus) was used to trace LV contours both at multiple slices from base to apex as well as just 3 slices (base, mid and apical) by two readers. End diastolic volume (EDV), end systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) were calculated using both assessment methods. Results There were no statistically significant differences between EF and LV volumes obtained by multi-slice vs 3-slice analysis for both readers (P > 0.05). For reader 1 (and 2), Bland-Altman plot revealed the mean difference in LVEF between multi-slice and 3-slice analysis was 0.4% (0.5%) with limits of agreement of -4.3% to 5.1% (-3.9% to 4.9%) (Figure 1). For both readers, all differences in EF between multi-slice and 3-slice analysis were within 5.3%. The measured volumes are listed in Table 1. Multi-slice assessment required approximately 10 minutes per study while 3-slice evaluation required about 3-5 minutes. Conclusions The LVEF obtained from either 3-slice or multi-slice evaluation of SSFP cine images closely correlate across various cardiac pathologies, thereby offering a method to reduce post-processing time. Of note, although the decreased LV volumes obtained by 3-slice segmentation are statistically significant, the difference of < 3.7% may not be clinically significant. Funding None.

Cystic adventitial disease (CAD) of the popliteal artery is a rare vascular disease of unknown etiology in which a mucin-containing cyst develops in the adventitial layer of the artery. We report the case of a 26-year-old male with CAD of the right popliteal artery diagnosed non-invasively with 3 Tesla cardiovascular magnetic resonance and confirmed on post-operative histopathology.

Echocardiography is considered as an initial imaging modality of choice in patients with congenital heart disease (CHD), and magnetic resonance (MR) imaging is preferred for detailed functional information. Multi-detector computed tomography (CT) plays an important role in clinical practice in assessing post-operative morphological and functional information of patients with complex CHD when echocardiography and MR imaging are not contributory. Radiologists should understand and become familiar with the complex morphology and physiology of CHD, as well as with various palliative and corrective surgical procedures performed in these patients, to obtain CT angiograms with diagnostic quality and promptly recognise imaging features of normal post-operative anatomy and complications of these complex surgeries.