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Aim To study patients with suspected pulmonary embolism (PE) with ventilation/perfusion tomographic technique (V/PSPECT) with implementation of holistic interpretation criteria.To give clear answer regarding existence of PE and to report additional scintigraphic findings if such exists.Method Lung scintigraphy for diagnosis of PE routinely includes ventilation and perfusion studies.With efficient technique and effective organization,V/PSPECT takes only one hour from referral to report.The ventilation study starts with inhalation of 25-30 MBq Technegas,usually 2-3 breaths.Immediately after ventilation SPECT,a dose of 100-120 MBq 99mTc MAA is given intravenously for perfusion imaging.During the examination,the supine patient carefully maintains the position between ventilation and perfusion acquisitions.Immobilization for only 20 minutes is well tolerated by nearly all patients.Examination in supine position is comfortable even for critically ill patients.It is also more convenient for the staff.It is noteworthy that V/PSPECT can be performed in all patients,since there is no contraindication related to age,radiation,contrast media or comorbidity.For the reconstruction and calculation of V/P quotient images,iterative OSEM is essential for SPECT reconstruction.Ventilation activity is subtracted from perfusion images.A valuable parameter in clinical SPECT is the Ventilation/Perfusion quotient,V/Pquotient.V/Pquotient is calculated after normalization of ventilation counts to perfusion counts.