Routine whole-body CT identifies clinically significant findings in patients supported with veno-venous extracorporeal membrane oxygenation

AIM

To determine the yield of routine whole-body computed tomography (CT) following extracorporeal membrane oxygenation (ECMO) initiation and to assess the association of these findings with prognosis.

MATERIALS AND METHODS

One hundred and ninety-eight consecutive patients with acute respiratory failure admitted for ECMO support between January 2015 and December 2019 who underwent whole-body CT performed within 48 h of ECMO initiation were examined in this single-institution retrospective study. CT findings were divided into three categories: clinically significant findings that may affect immediate management strategy or short-term outcomes; findings not related to hospital stay or outcome but require further workup; and benign findings that do not require further investigation. Logistic regression analysis was used to assess the association of CT findings with 7- and 30-day survival.

RESULTS

Clinically significant findings were present in 147 (74%) patients, findings requiring further workup were found in 82 (41%) patients, and benign findings were identified in 180 (90%) of the patients. Patients with clinically significant neurological findings had an elevated risk of death at 7 days (odds ratio [OR] 3.58; 95% confidence interval [CI] 1.29; 9.93; p=0.01), but not 30 days. Increasing numbers of clinically significant findings were associated with greater odds of mortality at 7 days (OR 1.70; 95% CI 1.08; 2.67; p=0.02) and 30 days (OR 1.41; 95% CI 1.02; 1.96; p=0.04).

CONCLUSIONS

Imaging patients at the point of admission for VV-ECMO with CT frequently identified clinically significant abnormalities with prognostic implications of these. These findings provide support for the use of more routine CT at the point of treatment escalation with prospective studies now required.

Impact of solitary pulmonary nodule size on qualitative and quantitative assessment using 18F-fluorodeoxyglucose PET/CT: the SPUTNIK trial

PURPOSE

To compare qualitative and semi-quantitative PET/CT criteria, and the impact of nodule size on the diagnosis of solitary pulmonary nodules in a prospective multicentre trial.

METHODS

Patients with an SPN on CT ≥ 8 and ≤ 30 mm were recruited to the SPUTNIK trial at 16 sites accredited by the UK PET Core Lab. Qualitative assessment used a five-point ordinal PET-grade compared to the mediastinal blood pool, and a combined PET/CT grade using the CT features. Semi-quantitative measures included SUVmax of the nodule, and as an uptake ratio to the mediastinal blood pool (SURBLOOD) or liver (SURLIVER). The endpoints were diagnosis of lung cancer via biopsy/histology or completion of 2-year follow-up. Impact of nodule size was analysed by comparison between nodule size tertiles.

RESULTS

Three hundred fifty-five participants completed PET/CT and 2-year follow-up, with 59% (209/355) malignant nodules. The AUCs of the three techniques were SUVmax 0.87 (95% CI 0.83;0.91); SURBLOOD 0.87 (95% CI 0.83; 0.91, p = 0.30 versus SUVmax); and SURLIVER 0.87 (95% CI 0.83; 0.91, p = 0.09 vs. SUVmax). The AUCs for all techniques remained stable across size tertiles (p > 0.1 for difference), although the optimal diagnostic threshold varied by size. For nodules < 12 mm, an SUVmax of 1.75 or visual uptake equal to the mediastinum yielded the highest accuracy. For nodules > 16 mm, an SUVmax ≥ 3.6 or visual PET uptake greater than the mediastinum was the most accurate.

CONCLUSION

In this multicentre trial, SUVmax was the most accurate technique for the diagnosis of solitary pulmonary nodules. Diagnostic thresholds should be altered according to nodule size.

TRIAL REGISTRATION

ISRCTN - ISRCTN30784948. ClinicalTrials.gov - NCT02013063.

CT in planning transcatheter aortic valve implantation procedures and risk assessment

For surgical aortic valve replacement, the Society of Thoracic Surgeons score (STSS) is the reference standard for the prediction of operative risk. In transcatheter aortic valve implantation (TAVI) though, where the procedure itself is minimally invasive, the traditional risk assessment is supplemented by CTA. Through a consistent approach to the acquisition of high-quality images and the standardised reporting of annular measurements and adverse root and vascular features, patients at risk of complications can be identified. In turn, this may allow for a personalised procedural approach and treatment strategies devised to potentially reduce or mitigate this risk. This article provides a systematic and standardised approach to pre-procedural work-up with computed tomography angiography (CTA) and explores the current state of evidence and future areas of development in this rapidly developing field.

Evidence-based anatomical review areas derived from systematic analysis of cases from a radiological departmental discrepancy meeting

AIM

To produce short checklists of specific anatomical review sites for different regions of the body based on the frequency of radiological errors reviewed at radiology discrepancy meetings, thereby creating "evidence-based" review areas for radiology reporting.

MATERIALS AND METHODS

A single centre discrepancy database was retrospectively reviewed from a 5-year period. All errors were classified by type, modality, body system, and specific anatomical location. Errors were assigned to one of four body regions: chest, abdominopelvic, central nervous system (CNS), and musculoskeletal (MSK). Frequencies of errors in anatomical locations were then analysed.

RESULTS

There were 561 errors in 477 examinations; 290 (46%) errors occurred in the abdomen/pelvis, 99 (15.7%) in the chest, 117 (18.5%) in the CNS, and 125 (19.9%) in the MSK system. In each body system, the five most common location were chest: lung bases on computed tomography (CT), apices on radiography, pulmonary vasculature, bones, and mediastinum; abdominopelvic: vasculature, colon, kidneys, liver, and pancreas; CNS: intracranial vasculature, peripheral cerebral grey matter, bone, parafalcine, and the frontotemporal lobes surrounding the Sylvian fissure; and MSK: calvarium, sacrum, pelvis, chest, and spine.

CONCLUSION

The five listed locations accounted for >50% of all perceptual errors suggesting an avenue for focused review at the end of reporting.

Imaging of cardiovascular risk in patients with Turner's syndrome

Turner's syndrome is a disorder defined by an absent or structurally abnormal second X chromosome and affects around 1 in 2000 newborn females. The standardised mortality ratio in Turner's syndrome is around three-times higher than in the general female population, mainly as a result of cardiovascular disorders. Most striking is the early age at which Turner's syndrome patients develop the life-threatening complications of cardiovascular disorders compared to the general population. The cardiovascular risk stratification in Turner's syndrome is challenging and imaging is not systematically used. The aim of this article is to review cardiovascular risks in this group of patients and discuss a systematic imaging approach for early identification of cardiovascular disorders in these patients.

Contrast-enhanced magnetic resonance lymphography in the assessment of lower limb lymphoedema

Chronic lower limb lymphoedema is a debilitating condition that may occur as a primary disorder or secondary to other conditions. Satisfactory visualization of the lymphatic vessels to aid diagnosis and surgical planning has been problematic. Historically, direct lymphography was used to visualize lymphatic vessels, although the significant surgical risks involved led to this being largely abandoned as a technique. Technetium-99m lymphoscintigraphy has been the mainstay of diagnosis for over two decades, but is hampered by inherently poor temporal and spatial resolution and limited anatomical detail. Contrast-enhanced magnetic resonance lymphography (MRL) is a relatively new technique that shows early promise in the evaluation of chronic lymphoedema. This article provides the procedural technique for lower limb MRL at both 1.5 and 3 T, discusses pathophysiology and classifications of lymphoedema, provides an overview of relevant lower limb lymphatic anatomy using MRL imaging, compares the various techniques used in the diagnosis of lower limb lymphoedema, shows common pathological MRL imaging findings, and describes alternative uses of MRL. Utilization of this technique will allow more accurate diagnosis and classification of patients suffering from lymphoedema.