Search

OBJECTIVES: Severe coronavirus disease 2019 is associated with an extensive pneumonitis and frequent coagulopathy. We sought the true prevalence of thrombotic complications in critically ill patients with severe coronavirus disease 2019 on the ICU, with or without extracorporeal membrane oxygenation. DESIGN: We undertook a single-center, retrospective analysis of 72 critically ill patients with coronavirus disease 2019-associated acute respiratory distress syndrome admitted to ICU. CT angiography of the thorax, abdomen, and pelvis were performed at admission as per routine institution protocols, with further imaging as clinically indicated. The prevalence of thrombotic complications and the relationship with coagulation parameters, other biomarkers, and survival were evaluated. SETTING: Coronavirus disease 2019 ICUs at a specialist cardiorespiratory center. PATIENTS: Seventy-two consecutive patients with coronavirus disease 2019 admitted to ICU during the study period (March 19, 2020, to June 23, 2020). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: All but one patient received thromboprophylaxis or therapeutic anticoagulation. Among 72 patients (male:female = 74%; mean age: 52 ± 10; 35 on extracorporeal membrane oxygenation), there were 54 thrombotic complications in 42 patients (58%), comprising 34 pulmonary arterial (47%), 15 peripheral venous (21%), and five (7%) systemic arterial thromboses/end-organ embolic complications. In those with pulmonary arterial thromboses, 93% were identified incidentally on first screening CT with only 7% suspected clinically. Biomarkers of coagulation (e.g., D-dimer, fibrinogen level, and activated partial thromboplastin time) or inflammation (WBC count, C-reactive protein) did not discriminate between patients with or without thrombotic complications. Fifty-one patients (76%) survived to discharge; 17 (24%) patients died. Mortality was significantly greater in patients with detectable thrombus (33% vs 10%; p = 0.022). CONCLUSIONS: There is a high prevalence of thrombotic complications, mainly pulmonary, among coronavirus disease 2019 patients admitted to ICU, despite anticoagulation. Detection of thrombus was usually incidental, not predicted by coagulation or inflammatory biomarkers, and associated with increased risk of death. Systematic CT imaging at admission should be considered in all coronavirus disease 2019 patients requiring ICU.

Objectives The West London lung screening pilot aimed to identify early-stage lung cancer by targeting low-dose CT (LDCT) to high risk participants. Successful implementation of screening requires maximising participant uptake and identifying those at highest risk. As well as reporting pre-specified baseline screening metrics, additional objectives were to 1) compare participant uptake between a mobile and hospital-based CT scanner and 2) evaluate the impact on cancer detection using two lung cancer risk models. Methods From primary care records, ever-smokers aged 60–75 were invited to a lung health check at a hospital or mobile site. Participants with PLCOM2012 6-yr risk ≥1.51 % and/or LLPv2 5-yr risk ≥2.0 % were offered a LDCT. Lung cancer detection rate, stage, and recall rates are reported. Participant uptake was compared at both sites (chi-squared test). LDCT eligibility and cancer detection rate were compared between those recruited under each risk model. Results Of 8366 potential participants invited, 1047/5135 (20.4 %) invitees responded to an invitation to the hospital site, and 702/3231 (21.7 %) to the mobile site (p = 0.14). The median distance travelled to the hospital site was less than to the mobile site (3.3 km vs 6.4 km, p Conclusion Targeted screening is effective in detecting early-stage lung cancer. Similar levels of participant uptake at a mobile and fixed site scanner were demonstrated, indicating that uptake was driven by factors in addition to scanner location. The LLPv2 model was more permissive; recruitment with PLCOM2012 alone would have missed several cancers.

Rationale: Clinical and epidemiologic data in coronavirus disease (COVID-19) have accrued rapidly since the outbreak, but few address the underlying pathophysiology. Objectives: To ascertain the physiologic, hematologic, and imaging basis of lung injury in severe COVID-19 pneumonia. Methods: Clinical, physiologic, and laboratory data were collated. Radiologic (computed tomography (CT) pulmonary angiography [n = 39] and dual-energy CT [DECT, n = 20]) studies were evaluated: observers quantified CT patterns (including the extent of abnormal lung and the presence and extent of dilated peripheral vessels) and perfusion defects on DECT. Coagulation status was assessed using thromboelastography. Measurements and Results: In 39 consecutive patients (male:female, 32:7; mean age, 53 ± 10 yr [range, 29–79 yr]; Black and minority ethnic, n = 25 [64%]), there was a significant vascular perfusion abnormality and increased physiologic dead space (dynamic compliance, 33.7 ± 14.7 ml/cm H2O; Murray lung injury score, 3.14 ± 0.53; mean ventilatory ratios, 2.6 ± 0.8) with evidence of hypercoagulability and fibrinolytic “shutdown”. The mean CT extent (±SD) of normally aerated lung, ground-glass opacification, and dense parenchymal opacification were 23.5 ± 16.7%, 36.3 ± 24.7%, and 42.7 ± 27.1%, respectively. Dilated peripheral vessels were present in 21/33 (63.6%) patients with at least two assessable lobes (including 10/21 [47.6%] with no evidence of acute pulmonary emboli). Perfusion defects on DECT (assessable in 18/20 [90%]) were present in all patients (wedge-shaped, n = 3; mottled, n = 9; mixed pattern, n = 6). Conclusions: Physiologic, hematologic, and imaging data show not only the presence of a hypercoagulable phenotype in severe COVID-19 pneumonia but also markedly impaired pulmonary perfusion likely caused by pulmonary angiopathy and thrombosis.

Regional lung cancer screening (LCS) is underway in England, involving a “lung health check” (LHC) and low-dose CT scan for those at high risk of cancer. Incidental findings from LHCs or CTs are usually referred to primary care. We describe the proportion of participants referred from the West London LCS pilot to primary care, the indications for referral, the number of general practitioner (GP) attendances and consequent changes to patient management, and provide an estimated cost-burden analysis for primary care. A small proportion (163/1542, 10.6%) of LHC attendees were referred to primary care, primarily for suspected undiagnosed chronic obstructive pulmonary disease (55/163, 33.7%) or for QRISK® (63/163, 38.7%) assessment. Ninety one of 159 (57.2%) participants consenting to follow-up attended GP appointments; costs incurred by primary care were estimated at £5.69/LHC participant. Patient management changes occurred in only 36/159 (22.6%) referred participants. LHCs result in a small increase to primary care workload provided a strict referral protocol is adhered to. Changes to patient management arising from incidental findings referrals are infrequent.

Background Corona Virus Disease 2019 (COVID-19) pneumonitis associated with severe respiratory failure carries a high mortality. Coagulopathy has emerged as a significant contributor to thrombotic complications. Case summary We describe two cases of severe COVID-19 pneumonitis refractory to conventional mechanical ventilation and proning position, transferred to our specialist centre for cardiorespiratory failure. Cross-sectional imaging demonstrated concurrent venous and aortic thrombosis with end-organ ischaemic changes. One patient received thrombolysis with a partial response. This could not be offered to the other patient due to a recent haemorrhagic event. Both patients died of multi-organ failure in the hospital. Discussion Concurrent aortic and venous thromboses are rare. This finding in COVID-19 cases, who were both critically ill patients, likely reflects the strongly thrombogenic nature of this illness which ultimately contributed to poor outcomes. The absence of deep vein thrombosis or a potential systemic source of embolism suggests in situ thrombosis. Further, the management of anticoagulation and thrombolysis is challenging in patients where an attendant bleeding risk exists.

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. Summary Significantly decreased (qualitative and quantitative) lung enhancement on dual-energy CT pulmonary angiography is an early feature of severe COVID-19 pneumonia and is associated with right ventricular dysfunction.

Introduction: Patients with pulmonary hypertension (PH) require repeat investigation to allow risk stratification and guide optimal therapy. These tests include CT and catheter studies utilising ionising radiation and contrast. Oxygen-enhanced magnetic resonance imaging (OE-MRI) is an alternative technique that provides measures related to regional ventilation, diffusion and perfusion and may provide novel biomarkers of PH severity. Aims: Assess correlation of OE-MRI measures with standard clinical measures of PH severity. Methods: Newly diagnosed group 1 or 4 PH patients underwent OE-MRI, with resultant measures compared with standard of care clinical outputs via Spearman’s correlation. Results: 12 patients were scanned (mean age 54.9±16.6 years old, mean pulmonary artery pressure 41.3±13.9mmHg). Significant correlation was seen between right ventricular (RV) end diastolic volume and median OE-MRI oxygen wash in time (WIT) (rs= 0.571, p= 0.048) and WIT interquartile range – a marker of spatial disease heterogeneity (rs= 0.857, p= 0.003). The WIT interquartile range also showed a moderate, negative association with RV ejection fraction (rs= -0.618, p=0.034). Interquartile range of native lung T1 relaxation time negatively correlated with TLCO (rs= -0.786, p= 0.021). Conclusions: Significant correlations have been demonstrated between OE-MRI measures of gas delivery and established markers of PH severity.

Acute, major pulmonary haemorrhage in children, is rare, may be life-threatening and at times presents atypically. Dieulafoy's disease of the bronchus presenting with recurrent or massive hemoptysis was first described in adults. Prior to reviewing the literature, we report an illustrative case of bronchial Dieulafoy's disease (BDD) in a child presenting unusually with massive apparent hematemesis. The source of bleeding is a bronchial artery that fails to taper as it terminates within the bronchial submucosa. A high index of suspicion is required to identify such lesions via radiological imaging and the role of bronchial artery embolisation is highlighted with video images of angiography included.

ObjectiveThe National Institute for Health and Care Excellence (NICE) clinical guidelines ‘chest pain of recent onset: assessment and diagnosis’ (update 2016) state CT coronary angiography (CTCA) should be offered as the first-line investigation for patients with stable chest pain. However, the current provision in the UK is unknown. We aimed to evaluate this and estimate the requirements for full implementation of the guidelines including geographical variation. Ancillary aims included surveying the number of CTCA-capable scanners and accredited practitioners in the UK.MethodsThe number of CTCA scans performed annually was surveyed across the National Health Service (NHS). The number of percutaneous coronary interventions performed for stable angina in the NHS in 2015 was applied to a model based on SCOT-HEART (CTCA in patients with suspected angina due to coronary heart disease: an open-label, parallel-group, multicentre trial) data to estimate the requirement for CTCA, for full guideline implementation. Details of CTCA-capable scanners were obtained from manufacturers and formally accredited practitioner details from professional societies.ResultsAn estimated 42 340 CTCAs are currently performed annually in the UK. We estimate that 350 000 would be required to fully implement the guidelines. 304 CTCA-capable scanners and 198 accredited practitioners were identified. A marked geographical variation between health regions was observed.ConclusionsThis study provides insight into the scale of increase in the provision of CTCA required to fully implement the updated NICE guidelines. A small specialist workforce and limited number of CTCA-capable scanners may present challenges to service expansion.

Background Low-dose computed tomography (LDCT) screening detects early-stage lung cancer and reduces mortality. We proposed a sequential approach targeted to a high-risk group as a potentially efficient screening strategy. Methods LungSEARCH was a national multicentre randomised trial. Current/ex-smokers with mild/moderate chronic obstructive pulmonary disease (COPD) were allocated (1:1) to have 5 years surveillance or not. Screened participants provided annual sputum samples for cytology and cytometry, and if abnormal were offered annual LDCT and autofluorescence bronchoscopy (AFB). Those with normal sputum provided annual samples. The primary end-point was the percentage of lung cancers diagnosed at stage I/II (nonsmall cell) or limited disease (small cell). Results 1568 participants were randomised during 2007–2011 from 10 UK centres. 85.2% of those screened provided an adequate baseline sputum sample. There were 42 lung cancers among 785 screened individuals and 36 lung cancers among 783 controls. 54.8% (23 out of 42) of screened individuals versus 45.2% (14 out of 31) of controls with known staging were diagnosed with early-stage disease (one-sided p=0.24). Relative risk was 1.21 (95% CI 0.75–1.95) or 0.82 (95% CI 0.52–1.31) for early-stage or advanced cancers, respectively. Overall sensitivity for sputum (in those randomised to surveillance) was low (40.5%) with a cumulative false-positive rate (FPR) of 32.8%. 55% of cancers had normal sputum results throughout. Among sputum-positive individuals who had AFB, sensitivity was 45.5% and cumulative FPR was 39.5%; the corresponding measures for those who had LDCT were 100% and 16.1%, respectively. Conclusions Our sequential strategy, using sputum cytology/cytometry to select high-risk individuals for AFB and LDCT, did not lead to a clear stage shift and did not improve the efficiency of lung cancer screening., While low-dose CT is now preferred for lung cancer screening, our randomised trial of smokers with COPD showed that a proposed sequential policy using sputum testing to select who receives low-dose CT and autofluorescence bronchoscopy was ineffective http://bit.ly/2JZujnx

Introduction: Eisenmenger Syndrome (ES) is an advanced form of pulmonary arterial hypertension associated with congenital heart disease. CT findings described in this group include extremely dilated pulmonary artery (PA), PA thrombus and calcification and hypertrophied bronchial arteries. Little is known about whether these findings are associated with clinical outcome. Aims: To document the radiological (CT) findings in ES and determine if they relate to prognosis. Methods: A single centre retrospective analysis of CT scans in ES patients was performed. The following were documented: PA diameter and trunk volume, presence of PA in-situ thrombus and calcification and hypertrophied bronchial arteries (presence, number and largest diameter). The calcification burden was further quantified using a modified Agatston score (as used in assessing coronary artery calcification). Logistic and Cox regression were used for statistical analysis. Results: A total of 104 ES patients were included (39 male, median age 33 [Range 14-69]). PA calcification was present in 29% and in situ thrombus in 21%. The mean PA diameter was 37±7mm and mean pulmonary trunk volume 102±59mm3. Bronchial artery hypertrophy was visible in 58% of patients with a diameter ranging from 2-5mm. During a median follow-up of 10 years from the index CT, 22 (29%) patients died. None of the parameters we measured related to mortality in this population. Conclusions: The commonly described radiological findings in ES do not appear to be a marker of prognosis but more likely reflect the long-standing severe pulmonary hypertension in these patients.

Primary ciliary dyskinesia (PCD) is a respiratory syndrome in which ‘random’ organ orientation can occur; with approximately 46% of patients developing situs inversus totalis at organogenesis. The aim of this study was to explore the relationship between organ anatomy and curve convexity by studying the prevalence and convexity of idiopathic scoliosis in PCD patients with and without situs inversus. Chest radiographs of PCD patients were systematically screened for existence of significant lateral spinal deviation using the Cobb angle. Positive values represented right-sided convexity. Curve convexity and Cobb angles were compared between PCD patients with situs inversus and normal anatomy. A total of 198 PCD patients were screened. The prevalence of scoliosis (Cobb >10°) and significant spinal asymmetry (Cobb 5–10°) was 8 and 23%, respectively. Curve convexity and Cobb angle were significantly different within both groups between situs inversus patients and patients with normal anatomy (P ≤ 0.009). Moreover, curve convexity correlated significantly with organ orientation (P

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.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.The high-pitch protocol better demonstrated the pulmonary veins (P=0.03) and all coronary segments (all P0.05), 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 (P0.01) and motion (P0.01) 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.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.

Congenital abnormalities or post-operative damage of the lymphatic system are rare causes of neonatal chylothorax or chylous ascites. Lymphangiography is a valuable tool for the diagnosis and treatment of lymphatic leaks and the assessment of congenital lymphatic abnormalities. We present two cases where lymphangiography was used to assist in thoracic duct embolization and surgical ligation. A review of the literature regarding the use of lymphangiography in neonates was also performed.

A common diagnostic dilemma in the assessment of small pulmonary nodules on computed tomography (CT) is in distinguishing benign intrapulmonary lymph nodes (IPLNs) from small primary pulmonary malignancies. Several CT features have been described of IPLNs, including attachment to a pleural surface. We had observed that IPLNs were often connected to a pulmonary vein and sought to evaluate the utility of this sign in discriminating IPLNs from lung adenocarcinomas. The frequency of other previously described CT signs of IPLNs was also compared with lung adenocarcinomas.We retrospectively identified histopathologically proven benign IPLNs (n=62) and small (15 mm) adenocarcinomas (n=61). CTs were reviewed to assess the number and type of pulmonary blood vessels arising from, or terminating within, these nodules, as well as other CT features of IPLNs (shape, location, and outline).The termination of a pulmonary artery within a nodule was strongly associated with primary lung adenocarcinoma (55.7%), and this was never seen in isolation in IPLNs (0%) (P0.001). IPLNs were more frequently associated with pulmonary venous connections (93.5%) compared with lung adenocarcinomas (21.3%) (P0.001). The connection to a pleural surface was observed in both IPLNs (38.7%) and lung adenocarcinomas (37.7%) (P=1.0).We describe a novel imaging marker that can help to differentiate between benign and malignant pulmonary nodules. However, attachment of a nodule to a pleural surface should not be used in isolation to distinguish IPLNs from lung malignancy.

Assessment of the left atrial appendage (LAA) for thrombus and anatomy is important prior to atrial fibrillation (AF) ablation and LAA exclusion. The use of cardiovascular CT (CCT) to detect LAA thrombus has been limited by the high incidence of pseudothrombus on single-pass studies. We evaluated the diagnostic accuracy of a two-phase protocol incorporating a limited low-dose delayed contrast-enhanced examination of the LAA, compared with a single-pass study for LAA morphological assessment, and transesophageal echocardiography (TEE) for the exclusion of thrombus. Consecutive patients (n = 122) undergoing left atrial interventions for AF were assessed. All had a two-phase CCT protocol (first-past scan plus a limited, 60-s delayed scan of the LAA) and TEE. Sensitivity, specificity, diagnostic accuracy, positive (PPV) and negative predictive values (NPV) were calculated for the detection of true thrombus on first-pass and delayed scans, using TEE as the gold standard. Overall, 20/122 (16.4 %) patients had filling defects on the first-pass study. All affected the full delineation of the LAA morphology; 17/20 (85 %) were confirmed as pseudo-filling defects. Three (15 %) were seen on late-pass and confirmed as true thrombi on TEE; a significant improvement in diagnostic performance relative to a single-pass scan (McNemar Chi-square 17, p < 0.001). The sensitivity, specificity, diagnostic accuracy, PPV and NPV was 100, 85.7, 86.1, 15.0 and 100 % respectively for first-pass scans, and 100 % for all parameters for the delayed scans. The median (range) additional radiation dose for the delayed scan was 0.4 (0.2-0.6) mSv. A low-dose delayed scan significantly improves the identification of true LAA anatomy and thrombus in patients undergoing LA intervention.

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.

Purpose This survey investigated current practice in intensive care unit radiology reporting using a survey tool. We ascertained physician attitudes regarding best practice. Methods A national survey was sent by email to a sample of intensive care units throughout UK between March and October 2014. The questionnaire determined current practice in reporting chest X-ray in intensive care units. It also identified differences between ‘routine’ and emergency and out-of-hours service. Further, it investigated how reports were documented and physician preferences for perceived best practice. Results Of 146 intensive care units contacted, 55% completed the survey. Of the sample, radiologists were solely responsible for chest X-ray reporting in 43.7%, intensive care unit clinicians in 33.7% and joint reporting in 25% of intensive care units. The reporting clinician on intensive care unit was a consultant in 67% of the centres. Written reports by radiologists were provided in 71.7% of cases. This was only 54.5% when intensive care unit clinicians reported chest X-rays. For all routine and emergency films, written reports by radiologists occurred in 63.1% of responders. Out-of-hours, 54.9% of clinicians described different reporting practice to normal hours. Regarding perceived best practice, 64.8% of clinicians preferred joint daily reporting, whilst 27% preferred a radiologist’s formal report. For emergencies, 55.2% of the survey recipients preferred a joint report. Conclusion Based on this cohort of UK intensive care units, at present, there appears to be a lack of a standardised system for image reporting. There are discrepancies in who reports chest X-rays, written documentation and the timing of reports, more so out-of-hours. Clinicians suggest that joint reporting should be the standard.

Aim To evaluate the impact of inspiratory effort and emphysema on reproducibility of pulmonary nodule volumetry. Materials and methods Eighty-eight nodules in 24 patients with emphysema were studied retrospectively. All patients had undergone volumetric inspiratory and end-expiratory thoracic computed tomography (CT) for consideration of bronchoscopic lung volume reduction. Inspiratory and expiratory nodule volumes were measured using commercially available software. Local emphysema extent was established by analysing a segmentation area extended circumferentially around each nodule (quantified as percent of lung with density of –950 HU or less). Lung volumes were established using the same software. Differences in inspiratory and expiratory nodule volumes were illustrated using the Bland–Altman test. The influences of percentage reduction in lung volume at expiration, local emphysema extent, and nodule size on nodule volume variability were tested with multiple linear regression. Results The majority of nodules (59/88 [67%]) showed an increased volume at expiration. Mean difference in nodule volume between expiration and inspiration was +7.5% (95% confidence interval: –24.1, 39.1%). No relationships were demonstrated between nodule volume variability and emphysema extent, degree of expiration, or nodule size. Conclusion Expiration causes a modest increase in volumetry-derived nodule volumes; however, the effect is unpredictable. Local emphysema extent had no significant effect on volume variability in the present cohort.

Objective High-pitch protocols are increasingly used in cardiovascular CT assessment for transcatheter aortic valve implantation (TAVI), but the impact on diagnostic image quality is not known. Methods We reviewed 95 consecutive TAVI studies: 44 (46%) high-pitch and 51 (54%) standard-pitch. Single high-pitch scans were performed regardless of heart rate. For standard-pitch acquisitions, a separate CT-aortogram and CT-coronary angiogram were performed with prospective gating, unless heart rate was ≥70 beats/min, when retrospective gating was used. The aortic root and coronary arteries were assessed for artefact (significant artefact=1; artefact not limiting diagnosis=2; no artefact=3). Aortic scans were considered diagnostic if the score was >1; the coronaries, if all three epicardial arteries scored >1. Results There was no significant difference in diagnostic image quality for either the aorta (artefact-free high-pitch: 31 (73%) scans vs standard-pitch: 40 (79%), p=0.340) or the coronary tree as a whole (10 (23%) vs 15 (29%), p=0.493). However, proximal coronary arteries were less well visualised using high-pitch acquisitions (16 (36%) vs 30 (59%), p=0.04). The median (IQR) radiation dose was significantly lower in the high-pitch cohort (dose-length product: 347 (318-476) vs 1227 (1150-1474) mGy cm, respectively, p

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.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.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 of70 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 HRD1, with a greater likelihood of artefact with increasing HRD.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 of3 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.

“Large airways disease” is a catch-all phrase encompassing a wide variety of pathology affecting the trachea, main, lobar, segmental, and proximal sub-segmental bronchi. Relevant pathologies can be divided into focal or diffuse processes and many conditions have classic appearances on computed tomography (CT). We provide a review of the imaging specifics of a wide range of large airway pathologies in adult, childhood, and fetal life with examples of common and rare pathologies ranging from well-known entities such as cystic fibrosis and allergic bronchopulmonary aspergillosis to rarities such as Williams–Campbell, primary ciliary dyskinesia, and congenital high-airway obstruction syndrome (CHAOS). Although the spatial and temporal resolution of modern multidetector CT lends itself well to the depiction of small structures such as the peripheral airways, concerns regarding radiation exposure and increasing interest in the role of functional and quantitative imaging have led to a surge in research into dose reduction in CT and both structural and functional airway imaging via magnetic resonance imaging. We discuss the current literature on these emerging techniques along with some exiting near future directions for large airways imaging.

AIM To evaluate multidisciplinary team (MDT) practice of radiological–pathological correlation of non-malignant biopsy results to examine the additive effect on the predictive values of computed tomography (CT) biopsy for malignancy and their subsequent management and outcomes. MATERIALS AND METHODS A service evaluation of the MDT management of non-malignant lung biopsy results (May 2014– May 2017) was undertaken. RESULTS Sixty patients had a non-malignant diagnosis on initial CT biopsy. Five patients were lost to follow-up leaving 55 in the final cohort. Forty-eight of the 55 patients had biopsy results classified as potentially non-specific, of which 26 were classified as concordant with radiology (e.g., organising pneumonia with compatible CT features), and 22 were classified as discordant (e.g., non-specific inflammation and yet sufficiently suspicious CT features). Patients with concordant negative pathology showed resolution (n=19) or stability (n=6) on imaging follow-up. One lesion demonstrated growth and was proven malignant on surgical resection. Discordant lesions were managed with repeat biopsy (n=8) or surgical resection (n=13), with 12 final benign diagnoses and nine malignancies. The negative predictive value of CT biopsy alone was 44/55 (80%), following repeat biopsy was 44/50 (88%), and following radiological–pathological assessment was 32/33 (97%). No patients underwent a shift in stage from time of biopsy to resection. CONCLUSION Combining radiological–pathological interpretation of negative biopsy results offers superior negative predictive value for lung malignancy without delayed diagnosis of lung cancer.

Summary Background: Erectile dysfunction (ED) and coronary artery disease (CAD) frequently coexist. ED may be present in the absence of cardiac symptoms 3–5 years before a coronary event. Exercise electrocardiography may identify flow-limiting CAD but cardiac computed tomography (CT) may identify early non-calcified plaque disease potentially vulnerable to rupture precipitating an acute event. Methods: Twenty men aged 39–69 years with ED and no cardiac symptoms underwent screening for cardiovascular risk including maximal treadmill exercise testing and CT coronary angiography. ED was confirmed using the Sexual Health Inventory for Men questionnaire. Findings: Eighteen had a low-density lipoprotein cholesterol > 3 mmol/l, none were diabetic and seven were hypertensive controlled on medical therapy. Coronary calcium scores were > 50 in 11 men (range: 54–1234) all of whom had angiographic CAD on CT. Nine of these had normal exercise ECGs. Four men had calcium scores of 6–17 and single plaque disease on CT. Five had normal cardiac CT studies. Interpretation: Erectile dysfunction may be a predictor of subclinical non-flow limiting CAD not detectable on exercise electrocardiography. Men with organic ED and no cardiac symptoms should be considered as ‘cardiac equivalents’ and aggressive risk reduction therapy initiated.

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 highlight the variation in clinical manifestations, imaging and management of four cases of unilateral pulmonary artery agenesis presenting in adulthood. METHOD: Four patients with unilateral pulmonary artery agenesis were referred to our institution between 1995 and 2005. They underwent a series of investigations, including chest radiography, echocardiography, ventilation perfusion scintigraphy, angiography, computed tomography (CT) and magnetic resonance imaging (MRI). RESULTS: Two of the four patients had absence of the right main pulmonary artery, whilst the remaining two patients had absence of the left main pulmonary artery. One patient showed a restrictive defect on pulmonary function tests. Two patients who had ventilation perfusion scintigraphy showed absent perfusion and reduced ventilation on the affected side. Angiography (where performed), CT and MRI confirmed the anatomy and the presence of multiple collaterals. Bronchiectasis was demonstrated on CT in two patients, with one also demonstrating a mosaic attenuation pattern. One patient had an incidental lung tumour on the side of the agenesis, which was diagnosed as a chondroid hamartoma on histology. Three of the four patients eventually underwent resection of the affected lung. CONCLUSION: Isolated unilateral pulmonary artery agenesis has a non-specific presentation. Awareness of this condition can lead to earlier diagnosis, with cross-sectional imaging making an important contribution.

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.

Background The technology used to perform catheter-based renal artery sympathetic denervation has evolved: catheters can now access arteries as small as 3mm in diameter and create ablation zones of up to 10mm in depth. Recent evidence suggests that the procedure may be more effective if a more thorough ablation strategy is employed. Limited data are available regarding inadvertent soft tissue thermal injury during such procedures. We used computed tomography (CT) to identify structures lying within the expected thermal ablation field or the ‘at risk zone' (ARZ). Methods 63 consecutive CT aortograms were reviewed, yielding 100 renal arteries anatomically eligible for treatment. Structures lying within a predefined ARZ (within 10mm of the renal artery wall) were recorded. Results The 63 subjects had a mean age of 74.6years, 48% were males and 88% had hypertension. The inferior vena cava and renal veins were in the ARZ in all cases. Psoas muscles and small bowel were within the ARZ in at least a fifth of the kidneys. Other structures found in the ARZ included the liver, pancreas, adrenal glands and diaphragm. Conclusions This study describes the variable anatomical relationship between renal arteries and important abdominal structures that may be exposed to thermal energy during modern denervation procedures. The consequence of delivering such thermal energy to these structures is unknown but clinicians should be alert to the presenting symptoms if these structures are damaged. CT may have a pre-procedure role in assessing this risk.

We validate a novel CT coronary angiography (CCTA) coronary calcium scoring system. 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. 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

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.

Abdominal symptoms are common in patients with AIDS. CT is frequently used to evaluate these symptoms.Findings on CT often non-diagnostic but nevertheless contribute towards patient management.Certain CT signs, together with a knowledge of the CD4 count, may help to indicate the likely diagnosis and enable early presumptive treatment.Post-treatment CT may be used to assess the resolution or progression of disease.CT is also useful in detecting intraabdominal complications arising from the treatment of AIDS.

Pulmonary manifestations of HIV disease are common.The pattern of disease has changed owing to a combination of factors. Plain radiography coupled with clinical assessment remains the starting point of investigation.CT is usually not required, except as a problem-solving tool.Whilst infection remains common, there are numerous non-infectious causes of acute chest symptoms.

Cardioembolic stroke is an important complication of atrial fibrillation. The thrombus responsible for this arises from the left atrial appendage (LAA) in >90% of cases, providing the rationale for device-based LAA closure as a means of thromboprophylaxis. Although oral anticoagulant therapy remains the mainstay for reducing the risk of stroke in patients with atrial fibrillation, an increasing number of patients, particularly those ineligible for conventional pharmacotherapy, are being offered percutaneous left atrial appendage closure. Cardiovascular CT can provide important information to assess the suitability of patients for LAA interventions and guide device selection and approach. The high spatial resolution and multiplanar capability of contemporary contrast-enhanced gated multidetector cardiovascular CT render it an ideal modality for noninvasively evaluating patients before intervention and assessing patients after intervention both for complications and procedural outcome.

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.

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. Koh, D. M. et al . Clinical Radiology (2001). 56 , 535–544

The aim of this study was to determine whether the ratio of the diameters of the main pulmonary artery and of the ascending aorta (rPA), as assessed on computed tomography (CT), is predictive of pulmonary arterial hypertension (PAH). We undertook a retrospective review of 50 patients with a wide range of pulmonary and cardiovascular diseases, who had undergone both chest CT and pulmonary arterial pressure measurements at right heart catheterization. Two independent observers made measurements of the diameter of the main pulmonary artery and of the ascending aorta on a single defined CT section. Body surface area (BSA, n = 48), pulmonary arteriolar resistance (n = 39), total lung capacity (n = 40), and aortic pressures (n = 50) were also recorded. rPA and pulmonary arterial diameter (dPA) were positively related to mean pulmonary artery pressure (Rs = 0.74, p0.0005 for both analyses). For patients younger than 50 years of age, mean pulmonary artery pressure correlated more strongly with rPA than dPA (Rs = 0.77, p0.00005, compared with Rs = 0.59, p0.005); and vice versa for patients older than 50 years of age (Rs = 0.63, p0.005, compared with Rs = 0.75, p0.00005). Using a mean pulmonary artery pressure greater than 20 mm Hg as indicative of PAH and a value of rPA1, the sensitivity, specificity, and positive and negative predictive values for determining PAH were 70% (26/37), 92% (12/13), 96% (26/27), and 52% (12/23), respectively. On multivariate analysis, rPA was positively related to mean pulmonary artery pressure (p0.0005), and negatively related to age (p0.0005), but was not related to BSA. By contrast, dPA showed some dependency on BSA (p0.0005), as well as on mean pulmonary arterial pressure. In patients younger than 50 years of age, we have found a strong correlation between rPA and mean pulmonary artery pressure in a heterogeneous study population, and this relationship is independent of BSA and sex. The presence of the sign "rPA1" is simple in practical CT reading to determine; if this is identified, there is a very high probability of pulmonary arterial hypertension, and clinicians should be alerted to this possibility.

Areas of decreased pulmonary attenuation representing small airways disease can be identified on computed tomography (CT). The objective was to quantify differences between inspiratory and expiratory CT for the detection of signs of small airways disease by four observers. Observer variation and the superiority of a fine versus a coarse grading system were also evaluated. Inspiratory and expiratory CT scans of 106 patients with conditions characterized by small airways disease and 19 healthy individuals were assessed by four observers. The extent of decreased attenuation was scored on a fine scale to the nearest 5% and also semiquantitatively on a coarser 5-point scale. Decreased attenuation was more extensive on expiratory CT (median. 6.7%; 0-76.7%) than on inspiratory CT (median, 3.8%; 0-81.7%). The fine scoring system had unacceptable interobserver variation (coefficient of variation, 80% for inspiratory CT, 70% for expiratory CT). The semiquantitative system had acceptable interobserver agreement (inspiratory CT k(w) = 0.64; expiratory CT, k(w) = 0.69) and good intra-observer agreement (inspiratory CT, k(w) = 0.80; expiratory CT, k(w) = 0.64). The major CT sign of small airways disease is more confidently quantified on expiratory CT. A fine scoring system is associated with unacceptable observer variation, and a coarse semiquantitative system is more suitable for quantitative studies of small airways disease.

A wide variety of thoracic disorders can arise in patients infected with the human immunodeficiency virus (HIV), although recent developments in the therapeutic management of AIDS patients has resulted in a changing pattern of chest disease. The use of CT in the diagnosis and management of these thoracic manifestations is discussed along with the CT appearances of the various infectious and non-infectious complications of the acquired immune deficiency syndrome (AIDS) which are commonly encountered in clinical practice.

Purpose: The purpose of this work was to investigate thin section CT image enhancement of subtle areas of decreased attenuation of the lung parenchyma in suspected airways disease. Method: Forty-seven consecutive patients with chronic sputum production underwent pulmonary function tests and high resolution CT (HRCT). Single section inspiratory (INSP), expiratory (EXP), and minimum intensity projection (MINIP) images through the lower lobes were acquired. A histogram stretch was applied to the INSP and MINIP images, generating two further image formats. The five image types were compared for the extent of decreased attenuation, observer confidence, and correlations with pulmonary function tests. Results: Interobserver variation was lowest with MINIP images (mean weighted K: MINIP 0.70, INSP sections 0.65, other image formats

To determine whether infiltrative lung, airway, or vascular disease can be differentiated as the cause of mosaic attenuation on thin-section computed tomographic (CT) scans of the lung.Thin-section CT scans were reviewed in 70 patients examined at three institutions. A mosaic attenuation pattern and pathologic or clinical proof of a specific type of disease were demonstrated. Causes of the mosaic pattern included infiltrative lung disease (n = 37), airway disease (n = 22), and vascular disease (n = 11). Thin-section CT findings were assessed independently by two observers blinded to clinical findings.The type of disease was identified correctly at CT in 58 (83%) of 70 patients by observer 1 and 57 (81%) of 70 patients by observer 2. Infiltrative lung disease was diagnosed correctly by both observers in 34 (92%) of 37 cases. Observer 1 identified 21 (95%) of 22 cases of airway disease and three (27%) of 11 cases of vascular disease. Observer 2 identified 19 (86%) of 22 cases of airway disease and four (36%) of 11 cases of vascular disease.Infiltrative lung disease and airway disease may be differentiated reliably as the cause of mosaic attenuation on lung CT scans, whereas vascular disease is often misinterpreted as infiltrative lung disease or airway disease.