Introduction: Pulmonary hypertension has been described for over a century in the context of scoliosis. Possible mechanisms of pulmonary arterial hypertension in this cohort include hypoxemia due to restrictive lung disease but may also include an element of mechanical deformation of the pulmonary circulation. Here we present a review of the history and data collected in patients with scoliosis.
We discuss the case of a 60 year old male with history of polio and scoliosis (Cobb angle 30⁰/Moderate Scoliosis) who is CPAP dependent but remains dyspneic.
Case, Methods and Measurements: Measures of pulmonary blood volume including BV5 (volume of vessels <5mm2 in cross-section) and total pulmonary blood vessel volume (TBV) were then extracted from volumetric CT imaging using 3D vascular reconstruction. The distal volume (BV5) was normalized by TBV and lung volume (LV) for each lobe as a marker of pruning.
BV5/TBV was 0.51 in the right lower lobe as compared to 0.41 in the left lower lobe. Similarly the left upper lobe had a BV5/TBV of 0.48 in comparison. BV5/LV was 21.8ml/L in the right lower lobe in comparison to 16.9 ml/L in the left lower lobe (Table 1). The loss of distal vasculature is shown in the Figure 1.
Discussion: Correlation between scoliosis and pulmonary hypertension has been described, including correlation between Cobb’s angle and RVSP in adolescent idiopathic Scoliosis, reported to be reversible upon surgical intervention. The exact pathophysiology of pulmonary hypertension in a patient with scoliosis is not clear. This report suggests that local changes in pulmonary vascular capacity and vascular dimension may play a role through compression and pruning of vasculature.
Conclusion: Measurement of pulmonary blood volume and vascular pruning may allow further understanding of mechanism of pulmonary vascular disease in scoliosis. To view results table, see full pdf