Pulmonary Venoocclusive Disease

Jud W. Gurney, MD, FACR

Key Facts

Terminology

Rare cause of pulmonary hypertension due primarily to occlusion of post-capillary venous radicles

Imaging Findings

Pulmonary arterial hypertension + smooth interlobular septal lines
Centrilobular ground-glass opacities and septal thickening have random distribution within lung
Thickened interlobular septa (80%), smooth
Centrilobular ground-glass opacities (65%)
Presence of 2 or more findings (lymphadenopathy, septal thickening, centrilobular ground-glass opacities)
- Sensitivity 75% and specificity 85% for PVOD

Top Differential Diagnoses

Pathology

Etiology: Idiopathic, post bone marrow transplant, chemotherapy drugs
Unknown incidence: PVOD may account for up to 10% of cases of PPH
Pathologic hallmark: Extensive occlusion of pulmonary veins by intimal thickening
Some evidence that proliferation of thin-walled capillaries in PCH histologic reaction to PVOD

Clinical Issues

Axial CECT shows smooth interlobular septal thickening

and centrilobular nodules

in a patient with pulmonary venoocclusive disease.

Axial HRCT shows centrilobular ground-glass nodules

in a patient with pulmonary artery hypertension

from pulmonary venoocclusive disease.

TERMINOLOGY

Abbreviations and Synonyms

Pulmonary venoocclusive disease (PVOD), pulmonary vasoocclusive disease
Isolated pulmonary venous sclerosis, obstructive disease of pulmonary veins, venous form of primary pulmonary hypertension, pulmonary artery hypertension (PAH)

Definitions

Rare cause of pulmonary hypertension due primarily to occlusion of post-capillary venous radicles

IMAGING FINDINGS

General Features

Best diagnostic clue: Pulmonary arterial hypertension + smooth interlobular septal lines
Patient position/location: Centrilobular ground-glass opacities and septal thickening have random distribution within lung

CT Findings

Lung
- Ground-glass opacities common (100%) but nonspecific
  - Centrilobular (65%), most specific pattern
  - Geographic (50%)
  - Diffuse
  - Mosaic
  - Perihilar
  - Patchy
- Thickened interlobular septa (80%), smooth
  - Range from few to numerous
- Peribronchovascular bundle thickening
- Distribution of septal thickening and ground-glass opacities: Random
Lymph nodes
- Mild lymphadenopathy, mean 15 ± 5 mm (50%)
Pulmonary vasculature
- Enlarged main and central pulmonary arteries
- Pulmonary vein caliber normal
Cardiac
- Dilated right atrium and right ventricle
- Thickened right ventricular myocardium
- Left ventricle and atrium have normal dimensions
Pleura-pericardium
- Pleural effusions (20-40%) may be bilateral, usually small
- Pericardial effusion (10%), small
Accuracy
- Presence of 2 or more findings (lymphadenopathy, septal thickening, centrilobular ground-glass opacities)
  - Sensitivity 75% and specificity of 85% for PVOD
  - Presence of only 1 finding cannot rule out PVOD
Life-threatening pulmonary edema
- May follow vasodilator therapy for primary pulmonary hypertension (PPH)
- Vasodilators include continuous intravenous infusion prostacyclin (epoprostenol) and calcium channel blockers
- Patients with centrilobular ground-glass opacities and septal lines at highest risk