CT Based Volumetric Reconstruction of the Pulmonary System in Scoliosis

Scoliosis has been associated with reduced pulmonary capacity, however the source of the reduction in capacity (left, right or both lungs) is not clear. The objective of this study was to investigate trends in left, right and total lung volume and left/right lung volume asymmetry with spinal curve severity in scoliosis. Three-dimensional volumetric reconstruction of the pulmonary system was performed on existing pre-operative CT scans for 28 idiopathic scoliosis patients. Left, right and total lung volumes, and left/right lung volume ratios were calculated and correlated with the following spinal curve parameters; major Cobb angle, rib hump, number of vertebrae in the major curve, most cephalad vertebra in the major curve, and thoracic kyphosis. Left/right lung volume ratio increases significantly with increasing rib hump. Left, right and total lung volumes were significantly correlated with rib hump and number of vertebrae in the major curve (P<0.05), and near-significantly correlated with most cephalad vertebra in the major curve (P<0.10). Shorter, higher, more rotated thoracic curves therefore restrict lung volume more than longer, lower, less rotated curves. The mean lung volume ratio for scoliosis patients was lower than for age-matched controls (P