Optimizing ventilation-perfusion lung scintigraphy: Parting with planar imaging

Aim of the study was to introduce and verify a ventilation-perfusion (V/Q) acquisition protocol that incorporates new developments in scintigraphy in order to allow for a more balanced comparison with other diagnostic procedu res. Methods: In 103 patients suspect of having pulmonary embolism, V/Q sca ns were acquired exclusively with SPECT technique. Ventilation was done wit h ultrafine aerosol. Planar images in eight directions were reconstructed t hrough addition of three consecutive SPECT projections. Three referees exam ined the scans in regard to type, localization, and extent of V/Q defects. Results: Using this protocol, significantly more defects, especially of sub segmental size, were detected (p <0.01). Sensitivity, and diagnostic accura cy were also significantly improved (p <0.01) to 0.96, and 0.99, respective ly. Furthermore, kappa values were increased up to 0.82 - a relevant enhanc ement in the ability to precisely localize V/Q defects. Conclusion: In conc lusion this protocol provides high-resolution tomographic scans as well as high-quality planer images within a short acquisition time. Due to the sign ificant increase in lesion detection, sensitivity, diagnostic accuracy, and anatomical localization of defects, it is a substantial improvement in the diagnosis of pulmonary embolism that will put V/Q scintigraphy on a par wi th other tomographic methods.