A STRUCTURED APPROACH TO THE INTERPRETATION AND REPORTING OF VENTILATION PERFUSION SCANS/

The aim of this study was to develop a structured approach to the repo rting and in particular the clinical interpretation of ventilation/per fusion (V/Q) scan results. An initial audit indicated that there were significant variations in the clinical management of patients particul arly after a non-diagnostic V/Q scan report. There were also differenc es in the approaches used to interpret the scan itself. In an attempt to improve this, a set of interpretation guidelines was produced based on the revised PIOPED data. To combat the problems with clinical inte rpretation, a standard method for assessing the pre-test clinical prob ability of pulmonary embolism was established. This clinical risk was then combined with the V/Q scan result to give an overall probability for the presence of pulmonary embolism. The more precise risk stratifi cation which resulted allowed explicit clinical advice on patient mana gement to be incorporated into the final report. A second audit was pe rformed with the revised methodology in place. The level of inter-obse rver variability for scan reporting decreased from 30% to 12%. The pri or assessment of clinical risk and the standardized method of combinin g this with the scan result led to an improvement in patient managemen t. This was particularly true for the non-diagnostic group, in whom ad ditional investigations were more appropriately used. A structured app roach which allows the pre-test probability of pulmonary embolism to b e combined in an explicit fashion with the V/Q scan result can provide a more precise risk stratification allowing appropriate recommendatio ns to be made. Such an approach can result in improved patient managem ent.