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.

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.

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.