Validation of the British Society of Thoracic Imaging guidelines for COVID-19 chest radiograph reporting

AIM

To validate the British Society of Thoracic Imaging issued guidelines for the categorisation of chest radiographs for coronavirus disease 2019 (COVID-19) reporting regarding reproducibility amongst radiologists and diagnostic performance.

MATERIALS AND METHODS

Chest radiographs from 50 patients with COVID-19, and 50 control patients with symptoms consistent with COVID-19 from prior to the emergence of the novel coronavirus were assessed by seven consultant radiologists with regards to the British Society of Thoracic Imaging guidelines.

RESULTS

The findings show excellent specificity (100%) and moderate sensitivity (44%) for guideline-defined Classic/Probable COVID-19, and substantial interobserver agreement (Fleiss' k=0.61). Fair agreement was observed for the “Indeterminate for COVID-19” (k=0.23), and “Non-COVID-19” (k=0.37) categories; furthermore, the sensitivity (0.26 and 0.14 respectively) and specificity (0.76, 0.80) of these categories for COVID-19 were not significantly different (McNemar's test p=0.18 and p=0.67).

CONCLUSION

An amalgamation of the categories of “Indeterminate for COVID-19” and “Non-COVID-19” into a single “not classic of COVID-19” classification would improve interobserver agreement, encompass patients with a similar probability of COVID-19, and remove the possibility of labelling patients with COVID-19 as “Non-COVID-19”, which is the presenting radiographic appearance in a significant minority (14%) of patients.

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Classic COVID-19 on chest radiograph is very specific for SARS-CoV-2.

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There is substantial interobserver agreement for Classic COVID-19.

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There is only fair agreement for Indeterminate and Non-COVID appearances.

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Indeterminate and Non-COVID categories have a similar probability of SARS-CoV-2.

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These categories should be amalgamated into a ‘Not Classic for COVID’ category.

Pre-surgical lung biopsy in management of solitary pulmonary nodules: a cost effectiveness analysis

Objectives: Tissue diagnosis prior to thoracic surgery with curative intent is vital in thoracic lesions concerning for lung cancer. Methods of obtaining tissue diagnosis are variable within the United Kingdom.Methods: We performed a model-based analysis to identify the most efficient method of diagnosis using both a health care perspective. Our analysis concerns adults in the UK presenting with a solitary pulmonary nodule suspicious for a primary lung malignancy, patients with more advanced disease (for example lymph node spread) were not considered. Model assumptions were derived from published sources and expert reviews, cost data were obtained from healthcare research group cost estimates (2016-17). Outcomes were measured in terms of costs experienced to healthcare trusts.Results: Our results show that CT guided percutaneous lung biopsy using an ambulatory approach, is the most cost-effective method of diagnosis. Indeed, using this approach, trust experience approximately half of the cost of an approach of surgical lung biopsy performed at the time of potential resection ('frozen section').Limitations and conclusions: Whilst this analysis is limited to the specific scenario of a solitary pulmonary nodule, these findings have implications for the implementation of lung cancer screening in the UK, which is likely to result in increased numbers of patients with such early disease.

Shear-Wave Elastography of Benign versus Malignant Musculoskeletal Soft-Tissue Masses: Comparison with Conventional US and MRI

Purpose To examine if shear-wave elastography (SWE) improves the accuracy of diagnosing soft-tissue masses as benign or malignant compared with US alone or in combination with MRI. Materials and Methods Two hundred six consecutive adult participants (mean age, 57.7 years; range, 18-91 years), including 89 men (median age, 56.0 years; range, 21-91 years) and 117 women (median age, 59.1 years; range, 18-88 years), who were referred for biopsy of a soft-tissue mass were prospectively recruited from December 2015 through March 2017. Participants underwent B-mode US, MRI, and SWE prior to biopsy. Three musculoskeletal radiologists independently reviewed US images alone, followed by US and MRI images together, and classified lesions as benign, probably benign, probably malignant, or malignant. For SWE, the area under the receiver operating characteristic (ROC) curve (AUC) was calculated for transverse shear-wave velocity (SWV). Multivariable logistic regression was used to investigate the association between SWE and malignancy alongside individual demographic and imaging variables. Results At histologic examination, 79 of 206 (38%) participants had malignant lesions. SWV showed good diagnostic accuracy for lesions classified as benign or probably benign by US alone (AUC = 0.87 [95% confidence interval {CI}: 0.79, 0.95]). SWV did not provide substantive diagnostic information for lesions classified as probably malignant or malignant, whether the classification was made with or without MRI. However, multivariable modeling indicated that diagnostic accuracy may vary by lesion position (interaction P = .02; superficial, odds ratio [OR] = 17.7 [95% CI: 1.50, 207], P = .02; deep/mixed, OR = 0.24 [95% CI: 0.07, 0.86], P = .03) and participant age (interaction P = .01; eg, age 43 years, OR = 0.72 [95% CI: 0.15, 3.5], P = .69; age 72 years, OR = 0.08 [95% CI: 0.02, 0.37], P = .001). Conclusion Shear-wave elastography can increase accuracy of soft-tissue lesion diagnosis in conjunction with US. However, a single cut-off may not be universally applicable with diagnostic accuracy that is affected by lesion position and patient age. © RSNA, 2018 Online supplemental material is available for this article.

A survey of UK percutaneous lung biopsy practice: current practices in the era of early detection, oncogenetic profiling, and targeted treatments

AIM

To ascertain current percutaneous lung biopsy practices around the UK.

MATERIALS AND METHODS

A web-based survey was sent to all British Society of Thoracic Imaging (BSTI) and British Society of Interventional Radiology (BSIR) members (May 2017) assessing all aspects of lung biopsy practice. Responses were collected anonymously.

RESULTS

Two hundred and thirty-nine completed responses were received (28.8% response rate). Of the respondents, 48.5% worked in a teaching hospital and 51.5% in a district general hospital, while 32.6% (78/239) were specialist thoracic radiologists, 29.2% (70/239) "general" radiologists with a thoracic subspecialty interest, and 28% (67/239) interventional radiologists. Of the respondents, 30.1% (72/239) did not require pre-biopsy lung function tests (PFTs); 45.6% (108/237) stopped aspirin before the procedure; 97.5% primarily use computed tomography (CT) guidance for biopsy and 88.7% (212/239) perform core needle biopsy (CNB); and 86.6% of radiologists use a co-axial technique. There was wide variation in the number of samples routinely taken with most radiologists performing 1-2 passes (55.9%) or 3-4 passes (40.8%). Sixty-four percent reported using chest drain prevention techniques to minimise the impact of iatrogenic pneumothorax, with needle aspiration most frequent (43.9%). Timing of post-biopsy chest radiography (CXR), performed by 95.8% (228/239), also varied greatly: most commonly at either 1 hour (23%), 2 hours (24.7%), or 4 hours (22.6%). Moreover, the time of patient discharge after uncomplicated biopsy was variable, although the majority (66.1%) discharge patients after ≥4 hours.

CONCLUSION

There are striking variations among surveyed UK radiologists performing lung biopsy in decision-making, pre-biopsy work-up, post-biopsy monitoring, management of pneumothorax, and discharge. The results suggest a need for new updated national percutaneous lung biopsy guidelines.

Use of transabdominal ultrasound-guided transjugular portal vein puncture on radiation dose in transjugular intrahepatic portosystemic shunt formation

PURPOSE

Transjugular intrahepatic portosystemic shunt (TIPS) creation is used to treat portal hypertension complications. Often the most challenging and time-consuming step in the procedure is the portal vein (PV) puncture. TIPS procedures are associated with prolonged fluoroscopy time and high patient radiation exposures. We measured the impact of transabdominal ultrasound guidance for PV puncture on duration of fluoroscopy time and dose.

METHODS

We retrospectively analyzed the radiation dose for all TIPS performed over a four-year period with transabdominal ultrasound guidance for PV puncture (n=212, with 210 performed successfully and data available for 206); fluoroscopy time, dose area product (DAP) and skin dose were recorded.

RESULTS

Mean fluoroscopy time was 12 min 9 s (SD, ±14 min 38 s), mean DAP was 40.3±73.1 Gy·cm2, and mean skin dose was 404.3±464.8 mGy.

CONCLUSION

Our results demonstrate that ultrasound-guided PV puncture results in low fluoroscopy times and radiation doses, which are markedly lower than the only published dose reference levels.

Necrotising pneumonia caused by non-PVL Staphylococcus aureus with 2-year follow-up

Necrotising pneumonia (NP) is a rare but life-threatening complication of pulmonary infection. It is characterised by progressive necrosis of lung parenchyma with cavitating foci evident upon radiological investigation. This article reports the case of a 52-year-old woman, immunocompetent healthcare professional presenting to Accident and Emergency with NP and Staphylococcus aureus septicaemia. The cavitating lesion was not identified on initial chest X-ray leading to a delay in antimicrobial optimisation. However, the patient went on to achieve a full symptomatic recovery in 1 month and complete radiological recovery at 2-year follow-up. Long-term prognosis for adult cases of NP currently remains undocumented. This case serves as the first piece of published evidence documenting full physiological and radiological recovery following appropriate treatment of NP in an immunocompetent adult patient.

Lung cancer tissue diagnosis in poor lung function: addressing the ongoing percutaneous lung biopsy FEV1 paradox using Heimlich valve

Many centres continue to decline percutaneous lung biopsy (PLB) in patients with poor lung function (particularly FEV1 <1 L) due to the theoretically increased risk of pneumothorax. This practice limits access to novel lung cancer therapies and minimally invasive surgical techniques. Our retrospective single-centre analysis of 212 patients undergoing PLB, all performed prospectively and blinded to lung function, demonstrates that using ambulatory Heimlich valve chest drain (HVCD) to treat significant postbiopsy pneumothorax facilitates safe, diagnostic, early discharge lung biopsy irrespective of lung function with neither FEV1 <1 L nor transfer coefficient for carbon monoxide (TLCO) <40% predicted shown to be independent predictors of HVCD insertion or pneumothorax outcomes. Incorporating ambulatory HVCD into standard PLB practice thereby elegantly bridges the gap that currently exists between tissue diagnosis in patients with poor lung function and the advanced therapeutic options available for this cohort.

Pharmacomechanical thrombectomy for salvage of TIPSS via successful -clearance of occlusive porto-splenic venous thrombosis

Transjugular intrahepatic porto-systemic shunt (TIPSS) is increasingly used to treat chronic portal vein thrombosis. However shunt thrombosis is a recognised early complication, particularly in those with thrombophilia. We outline a case of non-cirrhotic portal hypertension secondary to chronic portal vein occlusion where TIPSS was successfully performed but rapidly complicated by shunt thrombosis with extension into the portal and splenic veins. Mechanical thrombectomy and low dose systemic pharmacological thrombolysis were of limited benefit. Combined pharmacomechanical thrombectomy with the Trellis system restored -patency of the TIPSS, portal and splenic veins, with resultant good flow into the TIPSS. The patient remains well three months post-procedure. We describe the first case where the Trellis system has been successfully used to clear occlusive porto-splenic thrombus and restore flow through a blocked TIPSS.

Ambulatory percutaneous lung biopsy with early discharge and Heimlich valve management of iatrogenic pneumothorax: more for less

A prospective study of 489 consecutive outpatient image-guided percutaneous lung biopsies was conducted to determine whether early discharge, incorporating ambulatory Heimlich valve drain, is potentially advantageous to the National Health Service. Patients were discharged at 30 or 60 min, with significant pneumothoraces treated using Heimlich valve. 485 (99.2%) patients were successfully discharged early, 402 at 30 min. 87 (17.8%) patients developed pneumothorax: 52 required Heimlich valve; 5 proceeded to biopsy with Heimlich valve in situ. All drains were removed within 48 h, 38/52 (73.1%) at 24 h. Our results provide evidence for a paradigm shift in UK practice: early discharge lung biopsy, facilitated by ambulatory Heimlich valve, is safe with significant clinical and economic benefits.

Pan-insulin allergy and severe lipoatrophy complicating Type 2 diabetes

BACKGROUND

  Insulin allergy is a rare complication of insulin use. Localized lipoatrophy is also known to occur following subcutaneous injections of insulin.

CASE REPORT

  A 53-year-old non-obese female patient with Type 2 diabetes displayed local allergic-type symptoms to all available insulin preparations. This was complicated by the development of severe lipoatrophy on her abdominal and thigh injection sites and subsequently resulted in suboptimal glycaemic control.

CONCLUSIONS

  Whilst uncommon, insulin allergy and lipoatrophy can cause major problems in diabetic management. Potential pathophysiological mechanisms and a stepwise approach to management are discussed.

Does use of intraoperative cell-salvage delay recovery in patients undergoing elective abdominal aortic surgery?

A best evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether the use of intraoperative cell-salvage (ICS) leads to negative outcomes in patients undergoing elective abdominal aortic surgery? Altogether 305 papers were found using the reported search, of which 10 were judged to represent the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers were tabulated. None of the 10 papers included in the analysis demonstrated that ICS use led to significantly higher incidence of cardiac or septic postoperative complications. Similarly, length of intensive treatment unit (ITU) or hospital stay and mortality in elective abdominal aortic surgery were not adversely affected. Indeed two trials actually show a significantly shorter hospital stay after ICS use, one a shorter ITU stay and another suggests lower rates of chest sepsis. Based on these papers, we concluded that the use of ICS does not cause increased morbidity or mortality when compared to standard practise of transfusion of allogenic blood, and may actually improve some clinical outcomes. As abdominal aortic surgery inevitably causes significant intraoperative blood loss, in the range of 661-3755 ml as described in the papers detailed in this review, ICS is a useful and safe strategy to minimise use of allogenic blood.