Utility of high resolution computed tomography in predicting bronchiolitis obliterans syndrome following lung transplantation: preliminary findings

This study was undertaken to evaluate the efficacy of high resolution computed tomography (HRCT) in predicting the development of bronchiolitis obliterans syndrome (BOS) in lung transplant recipients. Fifty lung transplant patients who were clinically stable and without evidence of BOS were evaluated for the presence of four HRCT features reported to be associated with bronchiolitis obliterans: mosaic attenuation on inspiratory CT (mosaic perfusion), mosaic attenuation on expiratory CT (air trapping), bronchiectasis, and tree-in-bud opacities. CT exams were part of an annual surveillance process with the hope of predicting subsequent development of BOS. Diagnosis of BOS was made in 9 of 50 patients as indicated by a fall in FEV1 of greater than 20% of a stable baseline. None of the radiographic features associated with clinically established BOS were both sensitive and specific in the prediction of BOS. Air trapping demonstrated moderate sensitivity (56%, 5/9) and moderate specificity (76%, 35/46) for prediction of BOS in the year following the CT exam. Bronchiectasis, the most reliable indicator of the presence of BOS was a poor predictor of subsequent BOS with an 11% (1/9) sensitivity but had high specificity (96%, 44/46). No high resolution CT features accurately predicted the development of BOS.