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Introduction: Novel biomarkers are needed to improve assessment of ILD. Oxygen enhanced MRI (OE-MRI) monitors regional O2 delivery from changes in the MRI relaxation time T1 in response to hyperoxia. We present OE-MRI biomarkers in different ILD phenotypes (IPF, DI-ILD, CTD-ILD, HSP) acquired in a prospective observational study and compare them with lung function tests under standard clinical care. Methods: Patients recruited and scans analysed to date are summarised in fig 1. The OE MR parameters considered were: baseline T1, change in delta pO2 (ΔpO2), O2 wash-in time and ventilated volume fraction. Biomarker values at each visit and the change between visits were compared with lung function tests (FVC%, FEV1%, Tlco%, KCO%) using Pearson correlation (no correction for multiple comparisons). Results: In the IPF subgroup, T1 correlated with Tlco% and KCO% (r=-0.43, p=0.027 and r=-0.43, p=0.028). Changes between visits in ΔpO2 and in KCO%(r = 0.86, p=0.003) were also correlated. No significant correlations were found in other phenotypes. Conclusions: In IPF, change between visits in ΔpO2 correlates with the change in KCO%, but not in the other ILD subtypes.

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.

Since the emergence of the novel coronavirus SARS-CoV-2 in Wuhan, China in 2019 [1], the resulting COVID-19 disease has rapidly transitioned into a global pandemic with over 31 000 deaths and 215 000 infections in the UK as of 10th May 2020 [2]. Confirmation of SARS-CoV-2 infection requires reverse-transcriptase polymerase chain reaction (RT-PCR) testing [3]. Chest radiographic and/or computed tomography imaging is also central to diagnosis and management [4]., The National COVID-19 Chest Imaging Database (NCCID) is a repository of chest X-Ray, CT and MRI images and clinical data from COVID-19 patients across the UK, to support research and development of AI technology that may proffer insights into the disease.

Introduction: Apparent diffusion coefficient (ADC) is a measure of gas diffusion in the airspaces, where restrictions by tissue boundaries provide information about lung microstructure down to the alveolar level. Diffusion-weighted (DW) MRI of the lung with hyperpolarised helium in idiopathic pulmonary fibrosis (IPF) has shown that ADC correlates with DLCO, KCO and CT fibrosis score (Chan, H-F. et al. Radiology 2019; doi:10.1148/radiol.2019181714) but to date no data are available on the utility of 129-xenon (129Xe) diffusion in interstitial lung disease (ILD). Aim: To evaluate the ability of 129Xe DW-MRI to distinguish between ILD subtypes. Methods: A prospective, multicentre study of patients with ILD including drug induced ILD (DI-ILD), hypersensitivity pneumonitis (HP), IPF and connective tissue disease ILD (CTD-ILD). Hyperpolarised 129Xe DW-MRI was performed on a 1.5 T scanner and mean ADC was calculated. Results: To date, 33 patients (6 DI-ILD, 7 HP, 15 IPF, 5 CTD-ILD) have undergone baseline 129Xe DW-MRI. There was a significant difference in mean ADC between the ILD subtypes (p=0.011), with the significant difference occuring between the HP (median: 0.038cm2/s) and IPF (median: 0.048cm2/s) groups (p Conclusions: We demonstrate a correlation between mean 129Xe ADC and DLCO but not FVC. Our findings suggest significant differences in mean ADC between IPF and HP. Therefore, 129Xe DW-MRI could potentially have a role in differentiating changes in the airway microstructure in ILD subtypes.

Introduction: Hyperpolarised 129-xenon (129Xe) MR spectroscopy (MRS) can be used as a quantitative marker of gas exchange in interstitial lung disease (ILD). The ratio of the uptake of 129Xe in the red blood cells to the tissue/plasma (RBC:TP) has been shown to be reduced by 70% in idiopathic pulmonary fibrosis (IPF) patients when compared with healthy volunteers (Kaushik, S.S. et al. J Appl Physiol 2014; 117:577-585). In IPF, a significant decline in 129Xe RBC:TP over 12 months has been demonstrated but no significant change in DLCO or KCO (Weatherley, N.D. et al. Thorax 2018 [Epub ahead of print]). Aim: To compare longitudinal changes in 129Xe RBC:TP with changes in FVC and DLCO between ILD subtypes. Methods: A prospective, multicentre study of ILD patients including drug induced ILD (DI-ILD), hypersensitivity pneumonitis (HP), IPF and connective tissue disease ILD (CTD-ILD). Hyperpolarised 129Xe MRS was performed on a 1.5 T scanner. Results: To date, 18 patients (5 DI-ILD, 5 HP, 6 IPF, 2 CTD-ILD) have undergone 129Xe MRS on two separate visits (6 weeks apart for DI-ILD/HP and 6 months apart for IPF/CTD-ILD). There was a significant difference in longitudinal change in RBC:TP between the HP and IPF groups (p=0.022). Median change in RBC:TP in the HP and IPF groups was 0.022 and -0.023 respectively. There was no significant difference in longitudinal change in FVC% predicted (p=0.79) or DLCO% predicted (p=0.39) between the ILD subtypes. Conclusions: Our findings demonstrate that 129Xe RBC:TP has sensitivity to longitudinal change with significant differences between IPF and HP patients, whilst FVC and DLCO showed no change, suggesting that RBC:TP is more sensitive to change than PFTs in ILD.

Ataxia-Telangiectasia (A-T) is characterised by progressive ataxia, immunodeficiency, malignancy and chronic lung infection. Respiratory disease and cancer are leading causes of death. Imaging the lungs is challenging due to sensitivity to ionising radiation. Dynamic oxygen enhanced MRI (OE-MRI) characterises the arrival of oxygen into lung tissue by monitoring changes in MR signal on hyperoxia. No breath-hold is required. OEMRI has not previously been used in A-T. Aims: We aimed to assess the feasibility of undertaking OE-MRI in A-T. We hypothesized that children with A-T would be able to successfully complete an OE-MRI protocol. Methods: We studied children and young people with A-T. Participants have been enrolled to a 3 year cohort study. OE-MRI was done in a 1.5T GE systems machine, with image analysis with the Pulmolux (Bioxydyn, Ltd) platform. Results: We present early results from the first 5 participants (aged 9 – 15). All children undertook the OE-MRI protocol without sedation. Patient experience feedback from the scans has been positive. The median signal enhancement due to O2 breathing was 15%. Heterogeneity of oxygen delivery was observed, suggestive of ventilation variability. Conclusions: OE-MRI is feasible in children with A-T without sedation. Work is ongoing to understand OE-MRI reproducibility and role in A-T. Fig: Overlay of O2 enhancement map [%] over anatomical images.

Purpose: To investigate the capability of 3D-dynamic oxygen-enhanced MR (OE-MR) and Computed tomography (CT) in patients with Cystic Fibrosis (CF) and pulmonary function tests (PFT). Materials/Methods: 13 patients (median age: 28, female n=7) with a range of CF lung disease underwent OE-MR (1.5 T MR scanner). Coronal T1 parameter maps were obtained during free breathing. 3D coronal volumes of both lungs were acquired while patients alternately breathed room air and 100% oxygen. Images were fitted pixel by pixel. T1-parameter maps were generated and the following OE-MR parameters were measured: maximum O2-uptake(dPO2), wash-in and wash-out time. CT and PFT were available. Brody score was assessed by two radiologists. Total CT Brody score (CF-CT) was compared with PFT (%FEV1) and the OE-MR parameters using Pearson correlation. Results: Intraclass correlation for CF-CT(range:2-53,median 32) was high (0.86). dPO2, wash-in and wash-out time showed a significant correlation with CF-CT (dPo2:r=-0.691;p=0.009; wash-in/wash out:r=0.712;p=0.006). There was a significant correlation between dPO2, wash-in time and %FEV1 (O2-uptake: r=0.85;p Conclusion: Functional lung imaging using OE-MR has the capability to assess the severity of CF lung disease showing a significant correlation with %FEV1 and CT Brody score. For long-term CF care, avoidance of cumulative radiation burden is desirable and feasible using OE-MR.