More than 40 years ago Benjamin Burrows and his colleagues1 described the distinctive clinical, functional, radiological and pathological characteristics of the chronic obstructive pulmonary disease (COPD) phenotypes that they called emphysematous and bronchial types of chronic airways obstruction. They identified a subgroup of patients who were “thin” and had evidence of emphysema on chest x ray, while another subgroup was found to be of “stocky build” and had chest x ray changes suggestive of previous pulmonary inflammatory disease. Postmortem anatomical emphysema severity was positively related to emphysema grade on chest x ray, and with total lung capacity and age. Anatomical emphysema was, on the other hand, inversely related to chronic inflammatory changes on chest x ray, and with sputum volume, carbon dioxide tension and diffusing capacity.1 All patients had severe irreversible airways obstruction and died of respiratory failure but, noticeably, reduction in forced expiratory volume in 1 s (FEV₁) was not significantly related to anatomical emphysema extent and severity. Burrows et al introduced the terms type A and type B to empirically differentiate patients with the emphysematous type from those with the bronchial type of chronic airways obstruction.1 This phenotypic differentiation of patients with COPD, without being not even seriously questioned or challenged, has never been widely accepted and in more recent times it has been almost totally neglected by the pulmonary scientific community.

In this issue of Thorax, investigators from the Universities of Kyoto, Shiga, and Vancouver,2 continuing a long history of research activity in the field of the in vivo anatomical study of COPD by high resolution computed tomography (HRCT), elegantly bring back …