The effect of referrer education on ventilation perfusion imaging referral patterns

Abstract

Background: Ventilation perfusion (VQ) imaging for suspected pulmonary embolism (PE) is more likely to be diagnostically useful in the presence of a clear chest radiograph (CXR). An audit was performed to determine the effect of education of referrers on the referral patterns in this respect. Method: VQ scan reports before and after referrer education, in the form of a letter and oral presentation, were assessed: 49 reports before and 43 after. The contemporary CXR was assessed in isolation and defined as either normal, minimally abnormal or grossly abnormal. The final VQ scan result was correlated with the CXR category. Results: Before the education, 12% of CXRs were grossly abnormal whereas after this it fell to 2%. In the grossly abnormal CXR subgroup the indeterminate rate for the associated VQ scan was 100% in both time periods. Overall indeterminate rates for these periods were 28% and 22%. Conclusion: The decrease from 12% grossly abnormal CXRs to 2% is likely to be due to successful education of the referrers. Pre-assessment of the CXR by the nuclear medicine department before deciding on which specialist investigation to choose would probably further decrease the indeterminate rate for VQ scanning.