MORPHOLOGIC GRADING OF THE EMPHYSEMATOUS LUNG AND ITS RELATION TO IMPROVEMENT AFTER LUNG-VOLUME REDUCTION SURGERY

Background. The morphologic criteria for lung volume reduction surgery , such as severity and heterogeneity of disease, differ widely between patients, and this makes any comparison of functional results between centers difficult. Here we present a morphologic scoring system and d escribe its possible relation to functional results after lung volume reduction operations. Methods. Between September 1994 and December 199 6, 47 consecutive patients underwent bilateral lung volume reduction o perations. The morphology of emphysema was quantified with standard ch est roentgenograms and computed tomographic imaging, which were used t o define the following four variables: degree of hyperinflation (grade 0 to 4), degree of impairment in diaphragmatic mechanics, degree of h eterogeneity (grade 0 to 4), and severity of parenchymal destruction ( range, 0 to 48). Results. All four variables showed good reproducibili ty. Degree of heterogeneity had a significant influence on functional improvement in terms of forced expiratory volume in 1 second (p = 0.04 13, r(2) = 0.11). Severity of parenchymal destruction was significantl y associated with 30-day mortality: patients who died after operation (n = 4) had a severity of parenchymal destruction of 28.4 +/- 2.1 comp ared with 21.3 +/- 1.0 for those who survived (n = 43) (p = 0.003). Co nclusions. This morphologic scoring system is easy to use, is reproduc ible, and allows quantification of the morphology of emphysema, thereb y allowing definition of different patient subgroups. Such an exact mo rphologic quantification may help in the comparison of functional resu lts between centers. Furthermore, the risk factors for certain morphol ogic subgroups, such as patients with a homogeneous distribution patte rn, may be clarified in the future. (C) 1998 by The Society of Thoraci c Surgeons.