Quantitative lobar Tc99m-MAA SPECT/CT of the lung in pre-and post-procedural guidance for bronchoscopic lung volume reduction

Abstract

Objective This study investigates the role of single photon emission computed tomography (SPECT) with computed tomography (CT) in treating chronic obstructive pulmonary disease (COPD) through bronchoscopic lung volume reduction (BLVR). BLVR, a minimally invasive treatment for emphysema and hyperinflation of the lobes allows healthier lung regions to expand more efficiently by blocking the most diseased lobe(s). It is a viable option for patients with end-stage COPD who have limited treatments available. Methods This prospective study included 92 patients who underwent BLVR with quantitative SPECT/CT study pre- and post -procedure between November 2018 and June 2023. The mean age was 70 years (range 56-85). with 51 males and 41 females . SPECT/CT quantified perfusion for each lobe, and the lowest counts/volume ratio determined the procedural target. Postprocedure SPECT/CT assessed total atelectasis and perfusion shifts. The 6-minute walk test and pulmonary function tests were compared pre- and post-BLVR. Results SPECT/CT-guided BLVR showed clinical benefits (decreased oxygen requirements) and physiological improvements in total lung capacity, forced expiratory volume, and forced vital capacity (P < 0.05). Significant perfusion shifts were observed away from the target lobe, with unique patterns noted for ipsilateral and contralateral nontarget lobes (P < 0.05). Conclusion Quantitative lobar SPECT/CT in preprocedural guidance for BLVR proved useful in identifying suitable targets in multi-lobe homogeneous emphysema, resulting in physiological and clinical improvements for this patient group. The perfusion shift information provided by SPECT/CT offers valuable insights for pulmonologists.