Search

Uterine arteriovenous malformation (AVM) is a rare cause of vaginal bleeding and miscarriage. We report two cases of uterine AVMs in patients with a history of complex congenital heart disease, an association that has not been previously described. Both patients were treated by selective uterine artery embolization, a minimally invasive therapy that has revolutionized the management of uterine AVMs, thus offering an alternative to conventional hysterectomy. [ABSTRACT FROM AUTHOR]

Adult congenital heart disease is an increasingly prevalent condition with more than 135,000 patients affected in England alone. With this increased patient population and an increase in interventional procedures being performed on them, traditional imaging techniques such as cardiac magnetic resonance (CMR) may be unavailable locally or contra-indicated. Cardiac multidetector computed tomography (MDCT) is rapidly emerging as an alternative imaging method for the investigation of these patients and this review highlights the broad application of cardiac MDCT to this population and makes recommendations on the standardized reporting of complex congenital heart disease. [ABSTRACT FROM AUTHOR]

Background: The role of dual energy computed tomographic pulmonary angiography (DECTPA) in revealing vasculopathy in coronavirus disease 2019 (COVID-19) has not been fully explored., Purpose: To evaluate the relationship between DECTPA and disease duration, right ventricular dysfunction (RVD), lung compliance, D-dimer and obstruction index in COVID-19 pneumonia., Materials and Methods: This institutional review board approved this retrospective study, and waived the informed consent requirement. Between March-May 2020, 27 consecutive ventilated patients with severe COVID-19 pneumonia underwent DECTPA to diagnose pulmonary thrombus (PT); 11 underwent surveillance DECTPA 14 ±11.6 days later. Qualitative and quantitative analysis of perfused blood volume (PBV) maps recorded: i) perfusion defect 'pattern' (wedge-shaped, mottled or amorphous), ii) presence of PT and CT obstruction index (CTOI) and iii) PBV relative to pulmonary artery enhancement (PBV/PAenh); PBV/PAenh was also compared with seven healthy volunteers and correlated with D-Dimer and CTOI., Results: Amorphous (n=21), mottled (n=4), and wedge-shaped (n=2) perfusion defects were observed (M=20; mean age=56 ±8.7 years). Mean extent of perfusion defects=36.1%±17.2. Acute PT was present in 11/27(40.7%) patients. Only wedge-shaped defects corresponded with PT (2/27, 7.4%). Mean CTOI was 2.6±5.4 out of 40. PBV/PAenh (18.2 ±4.2%) was lower than in healthy volunteers (27 ±13.9%, p = 0.002). PBV/PAenh correlated with disease duration (β = 0.13, p = 0.04), and inversely correlated with RVD (β = -7.2, p = 0.001), persisting after controlling for confounders. There were no linkages between PBV/PAenh and D-dimer or CTOI., Conclusion: Perfusion defects and decreased PBV/PAenh are prevalent in severe COVID-19 pneumonia. PBV/PAenh correlates with disease duration and inversely correlates with RVD. PBV/PAenh may be an important marker of vasculopathy in severe COVID-19 pneumonia even in the absence of arterial thrombus., (2020 by the Radiological Society of North America, Inc.)

Cardiovascular computed tomography (CCT) is a cutting-edge imaging technique providing important, non-invasive, diagnostic information. Concerns exist regarding radiation exposure to patient populations, but achieving optimal image quality at the lowest doses can be challenging. This guide provides practical advice about how quality can be assured in any CCT unit or radiology department. Illustrated by real-world vignettes and data analysis from our own experience, we highlight a multidisciplinary team approach to each stage of the patient journey, the effectiveness of regular dose audit overseen by a CT optimisation group, and the importance of underused systolic scanning techniques, in order to drive significant dose reduction without loss of image quality or clinical confidence., (Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.)

Computed tomography coronary angiography is increasingly used in imaging departments in the investigation of patients with chest pain and suspected coronary artery disease. Due to the routine use of heart rate controlling medication and the potential for very high radiation doses during these scans, there is a need for guidance on best practice for departments performing this examination, so the patient can be assured of a good quality scan and outcome in a safe environment. This article is a summary of the document on 'Standards of practice of computed tomography coronary angiography (CTCA) in adult patients' published by the Royal College of Radiologists (RCR) in December 2014., (Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Purpose: We evaluated a high-pitch, non-electrocardiogram-gated cardiac computed tomographic protocol, designed to image both cardiac and extracardiac structures, including coronary arteries, in a neonatal population (less than 1 year old) that was referred for congenital heart disease assessment and compared it with an optimized standard-pitch protocol in an equivalent cohort., Materials and Methods: Twenty-nine high-pitch scans were compared with 31 age-matched, sex-matched, and weight-matched standard-pitch, dosimetrically equivalent scans. The visualization and subjective quality of both cardiac and extracardiac structures were scored by consensus between 2 trained blinded observers. Image noise, signal-to-noise and contrast-to-noise ratios, and radiation doses were also compared., Results: The high-pitch protocol better demonstrated the pulmonary veins (P=0.03) and all coronary segments (all P<0.05), except the distal right coronary artery (P=0.10), with no significant difference in the visualization of the remaining cardiac or extracardiac structures. Both contrast-to-noise and signal-to-noise ratios improved due to greater vessel opacity, with significantly fewer streak (P<0.01) and motion (P<0.01) artifacts. Image noise and computed tomographic dose index were comparable across the 2 techniques; however, the high-pitch acquisition resulted in a small, but statistically significant, increase in dose-length product [13.0 mGy.cm (9.0 to 17.3) vs. 11.0 mGy.cm (9.0 to 13.0), P=0.05] due to greater z-overscanning., Conclusions: In neonates, a high-pitch protocol improves coronary artery and pulmonary vein delineation compared with the standard-pitch protocol, allowing a more comprehensive assessment of cardiovascular anatomy while obviating the need for either patient sedation or heart rate control.

Objectives: We validate a novel CT coronary angiography (CCTA) coronary calcium scoring system., Methods: Calcium was quantified on CCTA images using a new patient-specific attenuation threshold: mean + 2SD of intra-coronary contrast density (HU). Using 335 patient data sets a conversion factor (CF) for predicting CACS from CCTA scores (CCTAS) was derived and validated in a separate cohort (n = 168). Bland-Altman analysis and weighted kappa for MESA centiles and Agatston risk groupings were calculated., Results: Multivariable linear regression yielded a CF: CACS = (1.185 × CCTAS) + (0.002 × CCTAS × attenuation threshold). When applied to CCTA data sets there was excellent correlation (r = 0.95; p < 0.0001) and agreement (mean difference -10.4 [95% limits of agreement -258.9 to 238.1]) with traditional calcium scores. Agreement was better for calcium scores below 500; however, MESA percentile agreement was better for high risk patients. Risk stratification was excellent (Agatston groups k = 0.88 and MESA centiles k = 0.91). Eliminating the dedicated CACS scan decreased patient radiation exposure by approximately one-third., Conclusion: CCTA calcium scores can accurately predict CACS using a simple, individualized, semiautomated approach reducing acquisition time and radiation exposure when evaluating patients for CAD. This method is not affected by the ROI location, imaging protocol, or tube voltage strengthening its clinical applicability., Key Points: • Coronary calcium scores can be reliably determined on contrast-enhanced cardiac CT • This score can accurately risk stratify patients • Elimination of a dedicated calcium scan reduces patient radiation by a third.

Transcatheter aortic valve implantation (TAVI) is an effective treatment option for patients with severe degenerative aortic valve stenosis who are high risk for conventional surgery. Computed tomography (CT) performed prior to TAVI can detect pathologies that could influence outcomes following the procedure, however the incidence, cost, and clinical impact of incidental findings has not previously been investigated. 279 patients underwent CT; 188 subsequently had TAVI and 91 were declined. Incidental findings were classified as clinically significant (requiring treatment), indeterminate (requiring further assessment), or clinically insignificant. The primary outcome measure was all-cause mortality up to 3 years. Costs incurred by additional investigations resultant to incidental findings were estimated using the UK Department of Health Payment Tariff. Incidental findings were common in both the TAVI and medical therapy cohorts (54.8 vs. 70.3%; P = 0.014). Subsequently, 45 extra investigations were recommended for the TAVI cohort, at an overall average cost of £32.69 per TAVI patient. In a univariate model, survival was significantly associated with the presence of a clinically significant or indeterminate finding (HR 1.61; P = 0.021). However, on multivariate analysis outcomes after TAVI were not influenced by any category of incidental finding. Incidental findings are common on CT scans performed prior to TAVI. However, the total cost involved in investigating these findings is low, and incidental findings do not independently identify patients with poorer outcomes after TAVI. The discovery of an incidental finding on CT should not necessarily influence or delay the decision to perform TAVI.

Aim: To assess the validity of virtual non-contrast (VNC) reconstructions for coronary artery calcium (CACS) and aortic valve calcium scoring (AVCS) in patients undergoing trans-catheter aortic valve implantation (TAVI)., Materials and Methods: Twenty-three consecutive TAVI patients underwent a three-step computed tomography (CCT) acquisition: (1) traditional CACS; (2) dual-energy (DE) CT coronary angiogram (CTCA); and (3) DE whole-body angiogram. Linear regression was used to model calcium scores generated from VNC images with traditional scores to derive a conversion factor [2.2 (95% CI: 1.97-2.58)]. The effective radiation dose for the TAVI protocol was compared to a standard control group. Bland-Altman analysis and weighted k-statistic were used to assess inter-method agreement for absolute score and risk centiles., Results: CACS and AVCS from VNC reconstructions correlated well with traditional scores (r = 0.94 and r = 0.86; both p < 0.0001). There was excellent agreement between VNC and non-contrast coronary calcium scores [mean difference -71.8 (95% limits of agreement -588.7 to 445.1)], with excellent risk stratification into risk centiles (k = 0.99). However, the agreement was weaker for the aortic valve [mean difference -210.6 (95% limits of agreement -1233.2 to 812)]. Interobserver variability was excellent for VNC CACS [mean difference of 6 (95% limits of agreement 134.1-122.1)], and AVCS [mean difference of -16.4 (95% limits of agreement 576 to -608.7)]. The effective doses for the DE TAVI protocol was 16.4% higher than standard TAVI protocol (22.7 versus 19.5 mSv, respectively) accounted for by the DE CTCA dose being 47.8% higher than that for a standard CTCA [9.9 (5.6-14.35) versus 6.7 (1.17-13.72) mSv; p < 0.01)., Conclusions: CACS and AVCS can be accurately quantified, and patients can be risk stratified using DECT VNC reconstructions. However, the dose from DE CTCA is significantly greater than the standard single-energy CTCA precluding the use of this technology in routine clinical practice., (Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

We validate a method of calcium scoring on CT coronary angiography (CTCA) and propose an algorithm for the assessment of patients with stable chest pain. 503 consecutive patients undergoing coronary artery calcium score (CACS) and CTCA were included. A 0.1 cm2 region of interest was used to determine the mean contrast density on CTCA images either in the left main stem (LM) or right coronary artery. Axial 3 mm CTCA images were scored for calcium using conventional software with a modified threshold: mean LM contrast density (HU) + 2SD. A conversion factor (CF) for predicting CACS from raw CTCA scores (rCTCAS) was determined using a multivariable regression model adjusted for model over-optimism (1,000 bootstrap samples). Accuracy of this method was determined using weighted kappa for NICE recommended CACS groupings (0, 1-400, >400) and Bland-Altman analysis for absolute score. With the CF applied: CACS = (1.183 × rCTCAS) + (0.002 × rCTCAS × threshold), there was excellent agreement between methods for absolute score (mean difference 5.44 [95% limits of agreement -207.0 to 217.8]). The method discriminated between high (>400) and low risk (<400) calcium scores with a sensitivity and specificity of 85 and 99%, and a PPV and NPV of 92 and 98%, respectively, and led to a significant reduction in radiation exposure (6.9 [5.1-10.2] vs. 5.2 [6.3-8.7] mSv; p < 0.0001). Our proposed method allows a comprehensive assessment of coronary artery pathology through the use of an individualised, semi-automated approach. If incorporated into stable chest pain guidelines the need for further functional testing or invasive angiography could be determined from CTCA alone, supporting a change to the current guidelines.

Aim: To prospectively analyse the occurrence of right coronary artery (RCA) artefact and assess its relationship with patient heart rate (HR) and HR variability (HRV) in order to determine the most appropriate parameters for high-pitch cardiovascular computed tomography (CT) acquisition, minimize the likelihood of artefact, and maximize the clinical benefit in consecutive clinical high-pitch CT coronary angiography (CA) examinations., Materials and Methods: One hundred and seventy-three patients undergoing high-pitch CTCA were prospectively assessed for the presence of RCA artefact. Median and maximum HR and the difference in predicted and actual acquisition HR (HR difference, HRD) were correlated from the electrocardiograms recorded at the time of acquisition., Results: Sixty-six percent of the cohort was male, with a median age of 54 (range 16-84 years). There were 53 cases of RCA artefact (30.6%); 26 (49.1%) of these required further imaging to fully delineate the RCA. Of the 53 cases with artefact, 81.1% affected the distal RCA and 18.9% were more proximal. Gender was not associated with an increased likelihood of the artefact (p = 0.14). RCA artefact decreased by 2% with each year of increasing age (p = 0.04). When compared with a reference HR of >70 beats/min, univariate analysis demonstrated RCA artefact significantly increased with both increasing median and maximum HR, whilst the incidence of RCA artefact increased for all HRD >1, with a greater likelihood of artefact with increasing HRD., Conclusion: The present results highlight the importance of optimizing patient HR in order to reduce the likelihood of RCA artefact. In addition to aggressive HR control to a median HR of ≤60 beats/min, the present results suggest limiting high-pitch acquisition to patients with HR variability of <3 beats/min. Therefore, use of beta-blockers is of crucial importance to both reduce HR and HR variability to optimize use of high-pitch single-heartbeat CTCA., (Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

For many years invasive angiographic techniques have been considered as the gold standard for the assessment of large arterial abnormalities. However, the complexities and complications inherent to invasive imaging have meant that more recently non-invasive techniques such as echocardiography, Magnetic Resonance Imaging (MRI) and multidetector CT (MDCT) have been increasingly used in congenital cardiovascular disorders. In particular, MDCT has emerged as a fundamental tool for the diagnosis and pre-surgical work-up of aortic abnormalities due to its high spatial resolution, large area of coverage, and short scan time, and therefore is now one of the most widely used modalities for the detection of congenital abnormalities of the aorta. The purpose of this pictorial review is to review the spectrum of abnormalities of the aorta than can be reliably detected by MDCT both in infants and in adulthood. Abnormalities of the aortic root, ascending aorta, aortic arch, and descending aorta will be described separately., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Background: The prevalence of idiopathic scoliosis in the general pediatric population is reported to be between 0.5% and 3.2%. Previous studies have reported an increased prevalence of scoliosis in children with cystic fibrosis (CF)., Hypothesis: The prevalence of scoliosis in CF children is greater than in the normal population., Methods: Chest X-rays of 319 patients attending the Royal Brompton CF Centre were reviewed. The Cobb angle of any spinal lateral curvature was measured. Scoliosis was defined as a Cobb angle of more than 10°., Results: Median age of the whole group of patients was 10.9 years (range 1.1-18 years), 53% were females. Seven patients (2.2%) had radiological signs of scoliosis, their mean age was 14.5 ± 2.3 years (range: 11.5-18 years), 5 were females. Age at onset of scoliosis was between 5 and 10 years for three patients and over 10 years for the others. All the curves were thoracic and with right convexity: apices between T7 and T9 for the single curves (n = 5) and between T4 and T5 (n = 2) for the double curves., Conclusion: CF patients showed a similar prevalence of scoliosis as in the normal population (2.2% vs. 0.5-3.2%). There was the same gender (female) and side (right-sided) predilection as in normal population., (Copyright © 2012 Wiley Periodicals, Inc.)

In patients with transposition of the great arteries, the identification of coronary anatomy is fundamental to optimal surgical outcome. A number of classifications describing the coronary vessels' origin and course in transposition of the great arteries have been published. However, all are limited to operative or pathological case series. They are often alphanumeric classifications that do not lend themselves to clinical practice; they do not consider certain important anatomical variations that may increase surgical morbidity and mortality, nor do they fully delineate coronary anatomy or define the relationship to adjacent structures seen with cardiovascular computed tomography. Using cardiovascular computed tomography for illustrative purposes, we propose and validate a universal sequential descriptive classification and an associated alphanumeric classification that may be used for all coronary anomalies with or without associated congenital heart disease., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

We report three children with an unusual radiological sign: "trachea with an air fluid level." We suggest this is related to paucity of cough leading to recurrent chest infections. Voluntary cough suppression as a cause of chronic lower respiratory tract infection is recorded in adults (The Lady Windermere Syndrome) but has not previously been reported in children. We propose that in these children impaired airway mucus clearance may be also be caused by voluntary cough suppression. However, the complex physiology of coughing means it is difficult to distinguish between true voluntary cough suppression and paucity of cough due to a subtle neurological deficit. In two patients, the cycle has led to permanent lung damage with bronchiectasis and reduced lung function. In the third, early diagnosis and multidisciplinary intervention has so far delayed progression to bronchiectasis. With greater awareness of this phenomenon in children, there is potential for effective early intervention with medical, physical, and psychological therapies., (Copyright © 2012 Wiley Periodicals, Inc.)

This review describes the broad spectrum of findings found in atrial isomerism, suggesting a sequential approach to image evaluation, and illustrates the most common situs disorders, for example, polysplenia and asplenia., (Copyright © 2012 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Background: CT coronary angiography (CTA) with 64 slice multi-detector CT (64-MDCT) has assumed an increasing role in clinical practice; however the high radiation dose associated with retrospective ECG-gated CTA has led to suggestions that a low dose prospectively gated strategy may be more appropriate. This study aims to assess the feasibility of this proposed strategy amongst standard referral for CTA in our centre., Methods: We retrospectively analyzed 200 consecutive clinical CTA studies assessing the number of cardiac phases required to allow full diagnostic visualisation of the coronary tree. We assessed whether the pre-test likelihood of coronary disease, heart rate, heart rate variability and range, current beta-blockers use, coronary calcium score, breathing artefact or study quality affected the number of phases required., Results: 125/200 patients (62.5%) required only a single phase for full diagnostic visualisation of the coronary tree [most commonly 65% of the R-R interval-109/125 (87.2%)]. A successful diagnostic single cardiac phase was most likely in patients with a low heart rate (Heart rate < 70 bpm OR = 2.64; p = 0.003 and heart rate < 60 bpm OR = 4.81; p < 0.001 respectively) and low likelihood of coronary disease [OR = 1.97 95% CI (1.09, 3.58) p = 0.025]., Conclusion: High image quality is possible using single phase analysis in those patients with low likelihood of coronary disease, low heart rates and full cooperation with inspiratory breath hold. In patients with HR of <60, prospective ECG-gated acquisitions reduce radiation dose but may be non-diagnostic in as many as one third. Careful patient selection is therefore essential., (Copyright © 2009. Published by Elsevier Ireland Ltd.)

Aims: Whilst parenchymal changes in pulmonary sequestrations are well described, there are comparatively little data on associated vascular changes and their extent. The aim of this study was to retrospectively review morphological changes within sequestrations, concentrating on vascular changes and associations with clinical parameters., Methods and Results: Twenty-seven resected cases of sequestrations (intralobar n = 20, extralobar n = 7) showed a male predominance (n = 16) and an age range of 2 months-60 years (average 13 years). Plexogenic vascular changes (medial hypertrophy and intimal fibrosis) were seen in 15 of 27 cases, as well as plexiform lesions in seven cases. Patients with plexogenic changes had a higher mean age compared with those lacking vascular changes (19 versus 6 years) and were more commonly female. Respiratory tract infections were associated solely with intralobar sequestrations. No other associations between presenting symptoms and histopathological parameters were identified. Adjacent lung showed lesser plexogenic changes in six of 22 intralobar cases. There were features of type 2 congenital cystic adenomatoid lesions in 63% of cases. Dissection of the supplying systemic artery (n = 1), intralesional aspergilloma (n = 1) and coexistent lymphangiomatosis (n = 1) were also identified., Conclusions: Hypertensive vascular changes are not uncommon in both intrapulmonary and extrapulmonary sequestrations, although their relative severity seems unrelated to presenting symptoms.

Introduction: Cardiac imaging is an emerging application of multidetector computed tomography (MDCT). This review summarizes the current capabilities, possible applications, limitations and developments of cardiac CT., Sources of Data: Relevant publications in peer reviewed literature and national and international guidelines are used to discuss important issues in cardiac CT imaging., Areas of Agreement and Controversy: There is broad consensus that coronary CT angiography is indicated in patients with an intermediate pre-test probability of coronary artery disease (CAD) when other non-invasive tests have been equivocal. In this context, CT can reliably exclude significant CAD. Cardiac CT also has an established role in the evaluation of bypass grafts and suspected coronary anomalies. Radiation exposure from CT procedures remains a concern, although techniques are now available to reduce the X-ray dosage without significantly compromising the image quality. However, with the current level of knowledge, the cardiac CT examinations are not justified to screen for CAD in asymptomatic individuals. Neither is it considered appropriate in patients with a high pre-test probability of CAD, for whom invasive catheter coronary angiography is usually of more benefit., Growing Points and Areas Timely for Developing Research: The ability to reconstruct the volumetric cardiac CT data set opens up avenues for advanced physiological analyses of the heart. For example, if CT myocardial perfusion assessment becomes a reality, there is potential to revolutionize the practice of MDCT imaging. Research is also ongoing to investigate whether cardiac CT has a role in the appropriate triage of patients with chest pain in the emergency department.

Background: Comprehensive assessment of pulmonary arterial hypertension (PAH) should identify structural causes and subsequent cardiopulmonary consequences of PAH. This currently requires the use of several imaging modalities. Computed tomography (CT) is routinely used for pulmonary angiography (CTPA). Our aim was to assess whether combined pulmonary and coronary angiography (CTPCA) using ECG-gated, multi-detector CT (MDCT) would allow satisfactory pulmonary angiography, coronary angiography and ventriculography to be combined into a single acquisition using a single imaging modality., Methods: We assessed CTPCA in 30 consecutive adult patients (mean age 41+/-11 years) with a diagnosis of PAH. In addition to the standard assessment of lung parenchyma and pulmonary vasculature, we assessed the ability of CT to satisfactorily visualise coronary vessels and biventricular function. Functional analysis included: end-diastolic volume (EDV), end-systolic volume (EDV), stroke volume (SV) and ejection fraction (EF) and mass and these parameters were correlated with same day cardiovascular magnetic resonance (CMR)., Results: Lung parenchyma, pulmonary and coronary vessels were fully visualised in all cases. Ventriculography correlated well with same day CMR (RVEDV r=0.94, +19.5+/-49.2 ml, RVESV r=0.93, +11.1+/-46.4 ml, RVSV r=0.60, +8.5+/-41.6 ml, RVEF r=0.77, -0.5+/-21.3% and RV mass r=0.73, -17.3+/-60.4 g, LVEDV r=0.68, +12.2+/-110 ml, LVESV r=0.69, +7.5+/-59.7 ml, LVSV r=0.54, +2.5+/-40.6 ml, LVEF r=0.73, -1.9+/-20.8% and LV mass r=0.87, -20.5+/-22.5 g (all p<0.001)). Associated congenital cardiovascular malformations were characterised in 22/30 cases., Conclusions: A CTPCA protocol allows safe, fast, comprehensive, non-invasive assessment of the possible anatomical causes and cardiopulmonary sequelae of PAH in adult patients, demonstrating congenital heart abnormalities, coronary artery disease and cardiac function.

Objectives: To assess intraobserver and interobserver variation in computed tomography coronary angiography (CTA) in 3 patient cohorts at very low, low-to-intermediate, and intermediate-to-high likelihood of coronary artery disease (CAD)., Methods: One hundred thirty-three patients underwent 64-channel CTA. Coronary arteries were analyzed by 2 experienced blinded observers and reported as having 0%, 1% to 29%, 30% to 49%, 50% to 69%, 70% to 99%, or 100% stenosis. Intraobserver and interobserver agreement was calculated at cohort level and combined., Results: Overall intraobserver and interobserver agreement was good (kappa = 0.74 and kappa = 0.78, respectively). Segmental agreement for stenoses 50% or greater and 70% or greater was greater than 96%. Disagreements were more likely in the presence of noneccentric calcification for both intraobserver (odds ratio = 0.45 and 0.22) and interobserver (odds ratio = 0.40 and 0.10) measurements., Conclusions: Interobserver and intraobserver variability for the detection of coronary stenoses on CTA is good and justifies routine clinical use. The presence of noneccentric calcium and mixed plaque morphology are important causes of disagreement.

Objectives: To assess intraobserver and interobserver variability in cardiac computed tomographic measurements of global biventricular function, left ventricular (LV) regional wall motion, systolic wall thickening, and first pass perfusion in 3 patient cohorts at very low, low to intermediate, and intermediate to high cardiac risk., Methods: One hundred thirty-three patients underwent 64-channel cardiac computed tomography. Images were analyzed by 2 experienced, blinded observers. Intraobserver and interobserver agreements were calculated for each cohort and were combined for patients with structurally normal hearts., Results: Intraobserver and interobserver agreements were good for all global and regional LV parameters with narrow levels of agreement. Right ventricular ejection fraction agreement was also good, but other right ventricular parameters showed wide levels of agreement., Conclusions: Biventricular ejection fraction, LV regional wall motion, and systolic wall thickening, volume, and mass show good reproducibility for use in standard clinical practice. Right ventricular volumetric and mass data in patients with congenital heart disease should be interpreted with caution.

Background: Cardiac computed tomography (CCT) has the potential to assess both coronary anatomy and ventricular function in a single study. We examined the agreement between CCT and myocardial perfusion scintigraphy (MPS) for the assessment of global and regional ventricular function., Methods and Results: Research CCT was performed in 52 patients with a low to intermediate likelihood of coronary artery disease referred for MPS. Left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular ejection fraction (LVEF), and myocardial wall motion and thickening were compared between techniques. In addition, myocardial contrast attenuation on CCT was compared with radiotracer uptake on MPS. LVEF values agreed well (mean difference, 4.1%; SD, 15.13%), but CCT left ventricular end-diastolic volume was greater compared with MPS (mean difference, 46.0 mL; SD, 33.34 mL) (P < .001). There was moderate agreement for segmental myocardial motion and thickening, with kappa values of 0.57 (95% confidence interval, 0.51-0.63) and 0.47 (95% confidence interval, 0.41-0.53), respectively. Seventeen patients had hypoattenuation in at least 1 myocardial segment on CCT. Three of four patients with concomitant abnormalities of wall motion and thickening on CCT had infarction in the same territory on MPS., Conclusions: There was good agreement for LVEF between CCT and MPS but myocardial volumes differed, and these modalities cannot be used interchangeably. Mild abnormalities of regional function are detected more commonly by CCT than by MPS. Myocardial hypoattenuation on CCT is highly specific for myocardial infarction when associated with reduction of systolic wall thickening and regional wall motion abnormality.

Background: Multislice computed tomography coronary angiography (CTA) was proposed as a method for investigating possible coronary artery disease (CAD) in patients who present with chest pain but with a low to intermediate likelihood of CAD. Sixty-four-channel CTA was compared prospectively with (99m)Tc-tetrofosmin myocardial perfusion scintigraphy (MPS) (as the gold standard in the detection of flow-limiting stenoses) for the detection of functionally significant CAD., Methods and Results: Fifty-two consecutive symptomatic patients with a low to intermediate likelihood of coronary artery disease, and who were referred for MPS, also underwent CTA. The CTA datasets were analyzed by two experienced observers who were blinded to the MPS data, and coronary artery segments were reported as < 50%, 50% to 69%, 70% to 99% stenoses, or occluded. The MPS images were similarly analyzed for inducible perfusion abnormalities, and coronary territories were identified. At the patient level, agreement between CTA and MPS for CTA lesions at >/= 50% was 87% (sensitivity, 100%; specificity, 84%; positive predictive value, 50%; negative predictive value, 100%). For CTA lesions, agreement at >/= 70% was 96% (sensitivity, 86%; specificity, 98%; positive predictive value, 86%; negative predictive value, 98%)., Conclusions: In patients with a low to intermediate likelihood of CAD, there is good correlation between MPS and CTA for the detection of functionally significant coronary artery stenoses when CTA detects a narrowing of >/= 70% severity. Computed tomography coronary angiography stenoses of 70% should be used to determine functional significance, and not 50%, as is the usual practice at present.

The widespread introduction of multidetector computed tomography (MDCT) into mainstream imaging departments has enabled many centres to undertake cardiac MDCT and, in particular, MDCT coronary angiography. This review highlights the areas that need consideration when introducing a new cardiac MDCT service and covers both technical and non-technical aspects. This includes equipment requirements, personnel, training, patient selection and preparation, cardiac CT protocols and post-processing techniques, and potential pitfalls.

Aim: To investigate the clinical range and severity of radiological findings in a cohort of patients with primary ciliary dyskinesia (PCD) receiving tertiary care., Materials and Methods: The case notes and clinical test results of 89 children attending the paediatric respiratory disease clinic at our institution were retrospectively analysed. Demographic details including age at diagnosis and common presenting signs and symptoms were studied. Results of chest radiographs, microscopy, and high-resolution computed tomography (HRCT) for quantification of lung damage were analysed., Results: In a cohort of 89 children with PCD, a presentation chest radiograph was available in 62% of patients (n=55), with all but one demonstrating changes of bronchial wall thickening. HRCT of the lungs, available in 26 patients, were scored using the system described by Brody et al. analysing five specific features of lung disease, including bronchiectasis, mucus plugging, peribronchial thickening, parenchymal changes of consolidation, and ground-glass density, and focal air-trapping in each lobe. Peribronchial thickening was observed using HRCT in 25 patients, while 20 patients had bronchiectasis. Severity scores were highest for the middle and the lingular lobes., Conclusion: The radiographic findings of the largest reported cohort of patients with PCD are presented, with associated clinical findings. Dextrocardia remains the commonest finding on chest radiography. HRCT demonstrates peribronchial thickening and bronchiectasis, which is most marked in the lower zones. Radiological scoring techniques developed for assessment of cystic fibrosis can also be applied for the assessment of disease severity in this patient population.

Aim: To describe the CT features of fibrosing mediastinitis., Materials and Methods: The clinical notes, histology, and CT images from 12 patients with fibrosing mediastinitis were reviewed. Clinical data regarding the presentation and suspected aetiology were correlated with location of mediastinal disease, calcification, effect on mediastinal structures, and additional pulmonary findings on computed tomography (CT)., Results: The mean age was 40.5 years, with seven female and five male patients. The most common presenting symptom was shortness of breath. Fibrosing mediastinitis diffusely infiltrated the mediastinum in five patients and was localized in seven. Calcification was present in two cases. Eleven of 12 cases had narrowing of mediastinal structures, including five with pulmonary artery narrowing, five with superior vena cava obstruction, four with bronchial narrowing, three with tracheal narrowing, and one with narrowing of the pulmonary vein. The disease was considered idiopathic in seven cases with a demonstrable aetiology in five cases. Eight out of 12 patients had additional pulmonary findings, including all patients with a known aetiology., Conclusions: In the present series of patients, fibrosing mediastinitis more commonly presented as a localized mediastinal mass than as diffuse mediastinal disease, with the anterior mediastinal compartment most frequently involved. Most cases were idiopathic compared with the majority of previous cases at this institution being ascribed to tuberculosis. There is a high incidence of concomitant pulmonary findings, in particular when an identifiable aetiology is present. Obstruction of vital structures frequently gives rise to complications.

Aim: To determine the radiological manifestations of IRIS (immune reconstitution inflammatory syndrome) in patients with HIV and mycobacterium tuberculosis co-infection, in the context of their demographic and clinical data., Materials and Methods: The radiological imaging, demographic and clinical data of 11 patients diagnosed with IRIS associated with HIV and mycobacterial tuberculosis co-infection were studied retrospectively. Where available, follow-up imaging studies were also reviewed., Results: The most common radiological feature of IRIS was lymph node enlargement (73%), with central low attenuation centres, in keeping with necrosis, present in most of these cases (88%). Most commonly affected were intra-abdominal nodes (70%), followed by axillary (40%) and mediastinal lymph nodes (36%). Within the lung parenchyma, diffuse, bilateral pulmonary nodules were seen in 55% of cases. Unilateral small volume pleural effusions were seen in two cases with associated parenchymal changes seen in only one. Small volume ascites was seen in two cases. Thirty-six percent of cases presented with new or worsening abscesses despite treatment. In this context, image-guided radiological drainage proved a useful adjunct to the conventional medical therapy for IRIS. The most common clinical signs of IRIS included fever (64%), abdominal pain (36%) and cough (27%)., Conclusion: We have described the radiological features that are characteristic in IRIS and the importance of putting these into context with the clinical and pathological findings as part of a multidisciplinary approach in making the diagnosis. The role of the radiologist is central in diagnosis, monitoring of disease progression and management of complications in patients with IRIS.

The introduction of multislice computed tomography (MSCT) has provided the thoracic radiologist with a powerful tool with which to image the lungs. Enthusiasm for new protocols should be tempered with concerns over the potential increase in radiation dose, and before older protocols are abandoned there should be good evidence that newer protocols are objectively superior. Ultimately, the best protocol is one that provides the most relevant clinical information at the lowest dose possible.

Aim: To describe the computed tomography (CT) features of human immunodeficiency virus (HIV)-associated Castleman's disease., Materials and Methods: Nine HIV-positive patients with biopsy-proven Castleman's disease were studied. Clinical and demographic data, CD4 count, histological diagnosis and human herpes type 8 (HHV8) serology or immunostaining results were recorded. CT images were reviewed independently by two radiologists., Results: CT findings included splenomegaly (n=7) and peripheral lymph node enlargement (axillary n=8, inguinal n=4). All nodes displayed mild to avid enhancement after intravenous administration of contrast material. Hepatomegaly was evident in seven patients. Other features included abdominal (n=6) and mediastinal (n=5) lymph node enlargement and pulmonary abnormalities (n=4). Patterns of parenchymal abnormality included bronchovascular nodularity (n=2) consolidation (n=1) and pleural effusion (n=2). On histological examination eight patients (spleen n=3, lymph node n=9, lung n=1, bone marrow n=1) had the plasma cell variant and one had mixed hyaline-vascular/plasma cell variant. The majority had either positive immunostaining for HHV8 or positive serology (n=8)., Conclusion: Common imaging features of multicentric Castleman's disease in HIV infection are hepatosplenomegaly and peripheral lymph node enlargement. Although these imaging features may suggest the diagnosis in the appropriate clinical context, they lack specificity and so biopsy is needed for diagnosis. In distinction from multicentric Castleman's disease in other populations the plasma cell variant is most commonly encountered, splenomegaly is a universal feature and there is a strong association with Kaposi's sarcoma.

Background: This study was designed to measure inter-observer variation between thoracic radiologists in the diagnosis of diffuse parenchymal lung disease (DPLD) using high resolution computed tomography (HRCT) and to identify areas of difficulty where expertise, in the form of national panels, would be of particular value., Methods: HRCT images of 131 patients with DPLD (from a tertiary referral hospital (n = 66) and regional teaching centres (n = 65)) were reviewed by 11 thoracic radiologists. Inter-observer variation for the first choice diagnosis was quantified using the unadjusted kappa coefficient of agreement. Observers stated differential diagnoses and assigned a percentage likelihood to each. A weighted kappa was calculated for the likelihood of each of the six most frequently diagnosed disease entities., Results: Observer agreement on the first choice diagnosis was moderate for the entire cohort (kappa = 0.48) and was higher for cases from regional centres (kappa = 0.60) than for cases from the tertiary referral centre (kappa = 0.34). 62% of cases from regional teaching centres were diagnosed with high confidence and good observer agreement (kappa = 0.77). Non-specific interstitial pneumonia (NSIP) was in the differential diagnosis in most disagreements (55%). Weighted kappa values quantifying the likelihood of specific diseases were moderate to good (mean 0.57, range 0.49-0.70)., Conclusion: There is good agreement between thoracic radiologists for the HRCT diagnosis of DPLD encountered in regional teaching centres. However, cases diagnosed with low confidence, particularly where NSIP is considered as a differential diagnosis, may benefit from the expertise of a reference panel.

High-resolution computed tomography (HRCT) is being increasingly used in the diagnostic work-up of paediatric patients with large and small airways disease due to its ability to provide valuable information far beyond that of other non-invasive investigations. This article highlights the key HRCT appearances of a range of conditions involving the airways in children, and where relevant, the role of HRCT in assessment of disease severity and monitoring of disease progression.

An increase in the prevalence of gallstones has been reported from the Middle East and the Republic of Yemen. Changing dietary habits and obesity are thought to be responsible but other local factors may contribute such as chewing the leaves of the khat plant (Catha edulis Forsk.) which is a widespread social custom in Yemen. We have studied the effects of khat chewing on gallbladder motility in a group of 10 healthy volunteers. All subjects underwent ultrasound measurements of gallbladder volume after chewing khat leaves or lettuce, which was used as the control. Results were compared after chewing for up to 2h in the fasting state and in response to a fatty meal. There was no significant change in gallbladder volume after chewing khat compared with lettuce in the fasting state (P=0.7) or in gallbladder emptying after a fatty meal (P=0.4) and we conclude that khat chewing has no clinically significant effect on gallbladder motility.

Purpose: To investigate whether asymmetric distribution of acute respiratory distress syndrome (ARDS) following lobectomy is due to compensatory hyperexpansion of the residual lung within the hemithorax operated on and to discern if this distribution reflects true asymmetry of the disease process., Materials and Methods: Retrospective review of the intensive care unit database was performed over a period of 6 years to identify all cases of lung injury following lung surgery that satisfied the American-European consensus criteria for ARDS. Time to onset following surgery, time of subsequent computed tomographic (CT) examination, patient age and sex, and nature of surgery were recorded, as well as eventual patient status (ie, death or discharge). Availability of both preoperative and postoperative CT scans was required for inclusion for further analysis. These images were analyzed on a commercial CT workstation for the volume of lung resected and the pre- and postoperative volume and density of each lung. Expected postoperative densities (preoperative density adjusted for volume) were compared with observed postoperative densities., Results: Review disclosed 583 patients who underwent lobectomy or segmentectomy. Seventeen patients (2.9%) developed postoperative ARDS. Nine of these patients had pre- and postoperative CT scans available for analysis. In eight of nine cases, density increased more in the nonoperated lung than in the operated lung (P =.01). The degree of density increase in the nonoperated lung was significantly greater (305 mg/mL; range, 48-449 mg/mL) than that in the operated lung (13 mg/mL; range, -198 to 231 mg/mL; P <.001)., Conclusion: Following lobectomy, there appears to be a truly asymmetric form of ARDS rather than compensatory hyperexpansion of the residual lung on the operated side., (Copyright RSNA, 2002)

Purpose: To assess the ability of a semi-quantitative latex agglutination D-dimer test Accuclot with bedside measurements of arterial oxygen saturation, respiratory and cardiac rates to exclude pulmonary embolism (PE) on computed tomographic pulmonary angiography (CTPA)., Materials and Methods: All patients referred to our CT unit for investigation of suspected acute pulmonary embolism were enrolled. Pulse oximetery, respiratory rate, heart rate and blood sampling for D-dimer testing were carried out just before CT. A high resolution CT (HRCT) of the chest was followed by a CT pulmonary angiogram (CTPA). The images were independently interpreted at a workstation with cine-paging and 2D reformation facilities by three consultant radiologists blinded to the clinical and laboratory data. If positive, the level of the most proximal embolus was recorded. Discordant imaging results were re-read collectively and consensus achieved., Results: A total of 101 patients were enrolled. The CTPA was positive for PE in 28/101 (28%). The D-dimer was positive in 65/101 (65%). Twenty-six patients had a positive CT and positive D-dimer, two a positive CT but negative D-dimer, 39 a negative CT and positive D-dimer, and 34 a negative CT and negative D-dimer. The negative predictive value of the Accuclot D-dimer test for excluding a pulmonary embolus on spiral CT was 0.94. Combining the D-dimer result with pulse oximetry (normal SaO2 > or = 90%) improved the negative predictive value to 0.97., Conclusion: A negative Accuclot D-dimer assay proved highly predictive for a negative CT pulmonary angiogram in suspected acute pulmonary embolus. If this D-dimer assay were included in the diagnostic algorithm of these patients a negative D-dimer would have unnecessary CTPA rendered in 36% of patients., (Copyright 2002 The Royal College of Radiologists.)

Transthoracic ultrasound (US) of the chest is useful in the evaluation of a wide range of peripheral parenchymal, pleural, and chest wall diseases. Furthermore, it is increasingly used to guide interventional procedures of the chest and pleural space. The technique lends itself to bedside use in the intensive care unit, where suboptimal radiography may mask or mimic clinically significant abnormalities. The authors discuss the uses, techniques and applications of US of the chest. The sonographic appearances of pleural diseases (pleural effusion, pneumothorax, pleural mass, and mesothelioma), parenchymal diseases (pneumonia, neoplasms, heart failure, infarct, and rounded atelectasis), chest wall abnormalities (chest wall tumor and rib fracture), and diaphragmatic paralysis are discussed. The use of US in guiding biopsy, thoracocentesis, and other interventional procedures of the lung, pleural space, and mediastinum are also reviewed., (Copyright RSNA, 2002)

Mycobacterial infection is re-emerging as a major health care concern. Although Mycobacterium tuberculosis(MTB) is still the most important pathogen, atypical mycobacterium (AMB) infections are becoming increasingly common. We present a pictorial review of the imaging features of these infections in the chest, abdomen, brain and musculoskeletal system. Imaging similarities and differences between the normal and the immunocompromised host will be highlighted.

High-resolution computed tomography (HRCT) has improved our understanding of many lung diseases in adults. The technique is used less often in children due to concerns regarding radiation dose. However, HRCT may provide important diagnostic information in a variety of lung diseases in children including airways diseases and diffuse interstitial lung disease. This review illustrates the HRCT appearances of a variety of conditions and describes the emerging role of the technique in children.

Aim: To evaluate the use of ultrasound-guided percutaneous injection of thrombin for treatment of femoral artery pseudoaneurysms., Method: Nine patients with a confirmed femoral false aneurysm were included in the study. 0.5-1 ml of a 2000 U/ml solution of activated bovine thrombin was injected under ultrasound visualization into the neck of the aneurysm to induce thrombosis. The parent artery and adjacent major vessels were checked during and after the procedure to exclude propagation of thrombus. A check ultrasound examination was undertaken on the following day., Results: Eight patients were successfully treated by a single injection. One patient required a second injection due to recurrence of their pseudoaneurysm 4 days after the initial treatment. The procedure was well tolerated in all cases and no complications were encountered., Conclusion: This small series provides further evidence that ultrasound-guided thrombin injection is a promising new method for the treatment of femoral false aneurysms.Hughes, M. J. et al. (2000). Clinical Radiology55, 749-751., (Copyright 2000 The Royal College of Radiologists.)

Aims: To document the presence and extent of air trapping on high resolution computed tomography (HRCT) in patients with pulmonary sarcoidosis and correlate HRCT features with pulmonary function tests., Methods: Twenty-one patients with pulmonary sarcoidosis underwent HRCT and pulmonary function assessment at presentation. Inspiratory and expiratory HRCT were assessed for the presence and extent of air trapping, ground-glass opacification, nodularity, septal thickening, bronchiectasis and parenchymal distortion. HRCT features were correlated with pulmonary function tests., Results: Air trapping on expiratory HRCT was present in 20/21 (95%) patients. The extent of air trapping correlated with percentage predicted residual volume (RV)/total lung capacity (TLC) (r = 0.499;P < 0.05) and percentage predicted maximal mid-expiratory flow rate between 25 and 75% of the vital capacity (r = -0.54;P < 0.05). Ground-glass opacification was present in four of 21 (19%), nodularity in 18/21 (86%), septal thickening in 18/21 (86%), traction bronchiectasis in 14/21 (67%) and distortion in 12/21 (57%) of patients; there were no significant relationships between these CT features and pulmonary function results., Conclusion: Air trapping is a common feature in sarcoidosis and correlates with evidence of small airways disease on pulmonary function testing., (Copyright 2000 The Royal College of Radiologists.)

The aim of this study was to describe the imaging features of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma. The chest radiographs (n = 18) and CT scans (n = 17) of 24 patients (18 men and 6 women) aged 27-78 years (mean = 56 years), with a known diagnosis of pulmonary MALT lymphoma, were retrospectively reviewed by two radiologists and the imaging findings are described. Six of the 24 patients had a history of an autoimmune disorder and 1 patient had acquired immune deficiency syndrome. Multiple pulmonary lesions were identified in 19 of 24 patients (79%) and solitary lesions in 4 of 24 patients (17%). Diffuse pulmonary infiltration was present in 1 patient. Lesions included masses or mass-like areas of consolidation (n = 21) and pulmonary nodules (n = 18). Associated findings were air bronchograms, airway dilatation, a positive angiogram sign and a halo of ground-glass shadowing at lesion margins. Peribronchovascular thickening was also observed, as were hilar or mediastinal lymph node enlargement and pleural effusions or thickening. Although rare, the diagnosis of pulmonary MALT lymphoma should be considered in patients with the imaging features described, particularly when in association with an indolent clinical course or a history of autoimmune disease.