Imaging description

Pulmonary veno-occlusive disease (PVOD) is considered a cause of pulmonary hypertension that preferentially affects the post-capillary pulmonary vasculature. The pathologic hallmark of PVOD is the extensive and diffuse occlusion of pulmonary veins by fibrous tissue. The imaging findings are a result of this fibrotic occlusion. Pulmonary and pleural lymphatics are dilated. The most consistent parenchymal change is thickening of the interlobular septa due to interstitial edema and deposition of collagen fibers along the septa [1]. On CT chest this is seen as peripheral interlobular septal thickening (Figures 57.1 and 57.2) Alveolar capillaries may become engorged and tortuous, and may resemble pulmonary capillary hemangiomatosis. On CT this is manifested by ground-glass opacities, predominately centrilobular ground-glass nodular opacities [2] (Figures 57.2 and 57.3). Other associated findings at CT include pleural effusions, pericardial effusions, enlarged central pulmonary arteries, normal central pulmonary vein and left atrium size, and mediastinal adenopathy.

Importance

The clinical presentation of PVOD (dyspnea, fatigue) is similar to primary pulmonary hypertension (PPH), but the treatments for PPH (vasodilator therapies) can be harmful and occasionally fatal in patients with PVOD, as they can induce fulminant pulmonary edema [2].