Tumor and normal tissue motion in the thorax during respiration: Analysis of volumetric and positional variations using 4D CT

Comparison of Spine, Carina, and Tumor as Registration Landmarks for Volumetric Image-Guided Lung Radiotherapy

“…van der Weide et al (35) used the carina to verify gated RT delivery and reported a high correlation coefficient for superoinferior motion between the carina and tumor (mean R, 0.84 AE 0.11). Weiss et al (36) also analyzed positional variations using 4D-CT and reported strong correlations between the centroid of the GTV and that of the lung (0.94 and 0.93 in the right and left lung, respectively) during a respiratory cycle. With paratracheal and subcarinal lymph nodes lying immediately adjacent to carina and trachea, the carina is expected to be a good anatomic surrogate for patients with mediastinal disease.…”

Respiratory Motion Changes of Lung Tumors Over the Course of Radiation Therapy Based on Respiration-Correlated Four-Dimensional Computed Tomography Scans

“…That study concludes that treatment margins should be based on tumor motion as opposed to external marker motion. More recently, Weiss et al (35) used respiration-correlated 4D-CT scans to calculate the centroid movement for different structures over the respiratory cycle. They conclude that the average correlation coefficients between the skin or diaphragm movement and the GTV movement were small.…”

Registration of temporal sequences of coronal and sagittal MR images through respiratory patterns

“…Although respiration clearly shows a repetitive character, the reduction of the respiratory organ deformation to a single parameter neglects all residual variability and may be a too coarse approximation in some cases. This leads to artifacts in the reconstructed images and considerable uncertainties [33][34][35][36].…”