Reduced ventilation–perfusion (V/Q) mismatch following endobronchial valve insertion demonstrated by Gallium‐68 V/Q photon emission tomography/computed tomography. Issue 5 (10th August 2017)

• Record Type: Journal Article
• Authors: Leong, Paul; Le Roux, Pierre‐Yves; Callahan, Jason; Siva, Shankar; Hofman, Michael S; Steinfort, Daniel P
• Is Part Of: Respirology case reports. Volume 5:Issue 5(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-08-10
• Subjects: Bronchial valve implants -- bronchoscopy -- positron emission tomography -- ventilation; Respiratory organs -- Diseases -- Periodicals; 616.2005
• DOI: 10.1002/rcr2.253
• Languages: English
• ISSNs: 2051-3380

Abstract

Abstract : Endobronchial valves (EBVs) are increasingly deployed in the management of severe emphysema. Initial studies focussed on volume reduction as the mechanism, with subsequent improvement in forced expiratory volume in 1 s (FEV1 ). More recent studies have emphasized importance of perfusion on predicting outcomes, though findings have been inconsistent. Gallium‐68 ventilation–perfusion (V/Q) photon emission tomography (PET)/computed tomography (CT) is a novel imaging modality with advantages in spatial resolution, quantitation, and speed over conventional V/Q scintigraphy. We report a pilot case in which V/Q‐PET/CT demonstrated discordant findings compared with quantitative CT analysis, and directed left lower lobe EBV placement. The patient experienced a significant improvement in 6‐min walk distance (6MWD) without change in spirometry. Post‐EBV V/Q‐PET/CT demonstrated a marked decrease in unmatched (detrimental) V/Q areas and improvement in overall V/Q matching on post‐EBV V/Q‐PET/CT. These preliminary novel findings suggest that EBVs improve V/Q matching and may explain the observed functional improvements. Abstract : Endobronchial valves (EBVs) are increasingly used in severe emphysema. Using Gallium‐68 ventilation–perfusion (V/Q) photon emission tomography (PET)/computed tomography (CT), we report a pilot case in which PET/CT findings were discordant to standard quantitative CT analysis. We deployed valves in a lobe where benefit was not predicted with standard quantitative CT, and found significant clinical improvement and improved V/Q matching on repeat imaging.