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Unilateral absence or extreme hypoplasia of pulmonary veins.

SUMMARY Three children with recurrent chest symptoms and signs caused by unilateral atresia or absence of the pulmonary veins are described, with a discussion of the seven reported cases of unilateral congenital pulmonary venous obstruction. The condition is rare but should enter into the differential diagnosis of recurrent unilateral pulmonary infection or oedema. Pulmonary arteriography is necessary and pulmonary artery wedge angiography is the most informative diagnostic procedure.