V/Q SPECT and SPECT/CT in Pulmonary Embolism

J Nucl Med Technol. 2023 Mar;51(1):9-15. doi: 10.2967/jnmt.122.264880. Epub 2023 Jan 4.


Ventilation and perfusion (V/Q) lung scintigraphy has been used in the assessment of patients with suspected pulmonary embolism for more than 50 y. Advances in imaging technology make SPECT and SPECT/CT feasible. This article will examine the application and technical considerations associated with performing 3-dimensional V/Q SPECT and the contribution of a coacquired CT scan. The literature tends to be mixed and contradictory in terms of appropriate investigation algorithms for pulmonary embolism. V/Q SPECT and SPECT/CT offer significant advantages over planar V/Q, with or without the advantages of Technegas ventilation, and if available should be the preferred option in the evaluation of patients with suspected pulmonary embolism.

Keywords: CTPA; SPECT; SPECT/CT; V/Q; lung imaging.

MeSH terms

  • Humans
  • Lung
  • Pulmonary Embolism*
  • Single Photon Emission Computed Tomography Computed Tomography
  • Tomography, Emission-Computed, Single-Photon* / methods
  • Tomography, X-Ray Computed / methods
  • Ventilation-Perfusion Ratio