The non-specificity of symptoms of pulmonary embolism (PE) makes imaging studies essential. The ventilation-perfusion lung scan (VQ) is the most frequently done nuclear medicine test for PE but the length of imaging time is inconvenient to the patient. The purpose of this study is to evaluate planar and SPECT lung perfusion scans interpreted using the PISA-PED criteria. In determining the sensitivity, specificity, positive and negative predictive values of the two imaging techniques, we also aim to present a simplified imaging method that foregoes the ventilation scan in the diagnosis of PE. This could lead to a change in the standard VQ scintigraphy protocol being used by nuclear medicine centers in the Philippines. This is a prospective study wherein fourteen patients suspected of having PE underwent planar and SPECT perfusion scans and CT pulmonary angiography, which was used as the gold standard for diagnosing PE. Planar and SPECT specificities and positive predictive values were the same at 100%. The sensitivity, negative predictive value, and accuracy of SPECT (85.7%,87.5%,92.8%, respectively) were all higher than planar scans (71.4%, 77.8%, 85.7%, respectively. A SPECT perfusion scan is superior to a planar perfusion scan in detecting pulmonary embolism. This implies that the standard ventilation-perfusion scan used by nuclear medicine centers in the country can be simplified. A ventilation scan can be omitted.

Human ; Male ; Female ; Aged ; Middle Aged ; Adult ; Young Adult ; Angiography ; Nuclear Medicine ; Perfusion Imaging ; Philippines ; Prospective Studies ; Pulmonary Embolism ; Radionuclide Imaging ; Tomography, Emission-computed, Single-photon ; Tomography, X-ray Computed ; Respiratory Tract Diseases ; Lung Diseases