Spatial correspondence of 4D CT ventilation and SPECT pulmonary perfusion defects in patients with malignant airway stenosis

摘要: To determine the spatial overlap agreement between four-dimensional computed tomography (4D CT) ventilation and single photon emission (SPECT) perfusion hypo-functioning pulmonary defect regions in a patient population with malignant airway stenosis. Treatment planning 4D CT images were obtained retrospectively for ten lung cancer patients radiographically demonstrated obstruction due to gross tumor volume. Each also received SPECT study within one week of CT, prior initiation treatment. Deformable image registration was used map corresponding tissue elements extreme component phase images, from which quantitative three-dimensional (3D) representing local specific constructed. Semi-automated segmentation percentile distribution performed identify regional defects distal known obstructing lesion. similarly by multiple observers delineate depicted on ventilation. Normalized Dice similarity coefficient (NDSC) indices determined each observer assess agreement. Tidal volumes evaluated versus measurements parenchyma segmentation. Linear regression resulted linear fit slope = 1.01 (R² 0.99). Respective values average DSC, NDSC(1 mm) NDSC(2 all cases 0.78, 0.88 0.99, indicating that, average, comparable threshold 1-2 mm uncertainty. Corresponding coefficients variation metrics range: 0.10%-19%. This is first quantitatively 3D clinically acquired CT. Results suggest high correlation methods sub-population