RT Journal Article SR Electronic T1 Perfusion measured with HRCT-approximated perfusion is comparable to SPECT/CT for patients with severe COPD JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 3800 DO 10.1183/13993003.congress-2022.3800 VO 60 IS suppl 66 A1 T D Koster A1 K Klooster A1 M Van Dijk A1 A Van Erp-Zeilstra A1 A Willems Van Beveren A1 J Pruim A1 J Charbonnier A1 D Slebos YR 2022 UL http://erj.ersjournals.com/content/60/suppl_66/3800.abstract AB Introduction: In patients with severe emphysema, who are evaluated for bronchoscopic lung volume reduction (BLVR) treatment, single photon-emission computed tomography (SPECT)/CT may be performed to determine the perfusion per lobe for definitive treatment decision making, which comes with additional radiation and costs.Aims and objectives: To investigate whether AI-based perfusion estimation from high resolution CT is comparable to SPECT/CT for perfusion on a lobar level.Methods: We performed a retrospective analysis of patients with severe emphysema, evaluated for BLVR. Perfusion approximation analysis (PXT) was performed to estimate lobar perfusion from non-contrast HRCT (LungQ, Thirona, The Netherlands). PXT was compared to the outcomes of SPECT/CT on lobar level.Results: We included 56 patients. The mean difference between PXT and SPECT/CT was -0.8% in the left lower lobe (p=0.09) and varied from -4.3% to 3.4% for the other lobes (p<0.001) (Table). The average PXT score correlated well with the outcome of the SPECT/CT (Pearson’s r=0.89-0.97, p<0.001) for both lungs and for all lobes separately.Conclusion: We found a high correlation in HRCT-approximated perfusion and SPECT/CT per lung and on a lobar level. There was a small but clinically irrelevant difference between the two methods. Lobar perfusion can be calculated using the PXT method which can save additional procedures, costs and radiation exposure.FootnotesCite this article as Eur Respir J 2022; 60: Suppl. 66, 3800.This article was presented at the 2022 ERS International Congress, in session “-”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).