Table 1.

Lung V/Q SPECT image scoring system

DS of the largest defect in each lung on SPECT

0 = No defect

1 = Defect <25% of one lung

2 = Defect 25–49% of one lung

3 = Defect 50–74% of one lung

4 = Defect 75–100% of one lung

Remaining lung DS on SPECT

1 = Homogeneous

2= Mild heterogeneity

3 = Moderate heterogeneity

4 = Marked heterogeneity

DS of total lung = ipsilateral lung DS + contralateral lung DS + RLDS = 1–12

Abbreviations: ventilation=V; perfusion=Q; single photon emission computed tomography=SPECT; defect score=DS. RLDS=remaining lung defect score, the degree of homogeneity of the tracer distribution outside the largest defect area in both lungs.

This method is modified from Gayed et al. J Thorac Oncol. 2008; 3(8):858–64.