The role of nuclear medicine in a case of Rendu-Osler-Weber disease with pulmonary involvement.

Rendu-Osler-Weber syndrome or hereditary hemorrhagic telangiectasia (HHT) is a rare systemic disease. Its primary pathogenic expression is multiple arteriovenous malformations (AVM) and severe hypoxia. A case of suspected pulmonary embolism in a 49-year-old male with intestinal, cardiac, and pulmonary HHT affection is reported. Pulmonary AVM could create an apparent mismatch perfusion defect evident upon ventilation and perfusion scan (V/Q scan), leading to misinterpretation. It reinforces the importance between clinics, anatomy, and functional evaluation. Care must be taken when interpreting V/Q scan and the reporting physician must be alert to the possible sources of errors.