Purpose: To assess the use of xenon ventilation maps (Xe-images) for predicting postoperative pulmonary function.
Materials and methods: After study approval by the institutional review board, written informed consent was obtained from 30 patients with lung tumors who underwent pre- and postoperative spirometry, pulmonary perfusion SPECT and dual-energy CT (80 kV and 140 kV/Sn) after single-breath inspiration of 35 % xenon. Xe-images were calculated by three-material decomposition. Sum of pixel values of the part to be resected (A) and of the whole lung (B) on Xe-images or lung perfusion SPECT, and volumes or the number of segments of the part to be resected (A) and of the whole lung (B) on Xe-images were enumerated, respectively. We multiplied (1 - A/B) by each preoperative value from spirometry for prediction. Predictions by each of the four methods were compared with postoperative values.
Results: Predicted values for vital capacity (VC), forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) by the four methods regressed significantly with measured values (R (2) = 0.56-0.77, p < 0.001 for all).
Conclusion: Analysis of Xe-images can predict postoperative VC, FVC and FEV1 with accuracy comparable to that of CT volumetry.