Perfusion scintigraphy in the diagnosis of pulmonary embolism: a self-assessment quiz.

The authors present ten case reports with lung scintigrams in a format suitable for a self-assessment quiz. The first seven cases include perfusion scintigrams and the final diagnosis was established by postmortem examination. The last three studies include ventilation images (using nebulized Tc-99m tin colloid) and the final diagnosis established by nonradionuclide studies. The authors believe this quiz demonstrates the necessity for ventilation studies when using lung scintigraphy for a positive diagnosis.