[Use of scintigraph in the diagnosis of pulmonary sequestration]

To evaluate scintigraphic findings in cases of pulmonary sequestration, perfusion lung scintigrams were obtained with Tc-99m macroaggregated albumin, and radionuclide angiocardiograms were obtained with Tc-99m pertechnetate in 5 cases of pulmonary sequestration. Perfusion lung scintigrams showed well-defined, segmental perfusion defects in the left lower lobe adjacent to the diaphragm, including S8, S9, and S10. The radionuclide angiocardiograms delineated abnormal systemic blood flow through the descending aorta to the left lower lobe. Subtraction scintigrams were obtained from two images of different phase in the aortic phase on the radionuclide angiograms; these images showed the abnormal systemic blood flow through the descending aorta more clearly than did the conventional radionuclide angiocardiograms. Thus, perfusion lung scintigrams and radionuclide angiocardiograms may be useful as non-invasive aids in the diagnosis of pulmonary sequestration.