Magnetic resonance imaging of lung signal intensity and dimensions in patients with advanced lung disease before and after single lung transplantation.

A retrospective analysis of lung signal intensity normalized for fat and lung cross-sectional area normalized for body surface area was obtained from cardiac gated spin-echo (echo time 40 ms) images before and after single-lung transplantation in 12 patients with pulmonary airway disease (seven emphysema, two bronchiectasis and three obliterative bronchiolitis) and 14 with interstitial lung disease (three pulmonary fibrosis, four fibrosing alveolitis and seven lymphangioleiomyomatosis). Nine healthy volunteers were studied for comparison. The native lung in pulmonary airway disease without inflammatory processes has normalised signal intensity (79 +/- 12%) similar to that of the control (100 +/- 6%) while interstitial lung disease had a higher normalised signal intensity (172 +/- 33%; P = < 0.05). The transplanted lung had a similar normalised signal intensity (103 +/- 12%) to that of the control except when there was a rejection reaction (one patient) or infection (two patients). Compared with the control, the native lung was smaller in pulmonary fibrosis (50 +/- 8%) and fibrosing alveolitis (78 +/- 8%), while larger in lymphangioleiomyomatosis (136 +/- 6%) and pulmonary airway disease (165 +/- 8%). The cross-sectional area of the transplanted lung was comparable to that of the control (100 +/- 13%). Distinctive features of lung normalised signal intensity and cross-sectional area were demonstrated in patients with pulmonary airway disease and interstitial lung disease before lung transplantation. These measurements could be useful noninvasive indices for assessment of the transplanted lung and for frequent follow-up of patients without exposure to ionizing radiation. Future developments are required to enhance lung signal sufficiently to detect less severe diseases.