Two-dimensional SPECT display and three methods for integrated visualization of SPECT and MRI patient data are evaluated in a multiobserver study to determine whether localization of functional data can be improved by adding anatomical information to the display.
Methods: SPECT and MRI data of 30 patients were gathered and presented using four types of display: one of SPECT in isolation, two integrated two-dimensional displays and one integrated three-dimensional display. Cold and hot spots in the peripheral cortex were preselected and indicated on black-and-white hard copies of the image data. Nuclear medicine physicians were asked to assign the corresponding spots in the image data on the computer screen to a lobe and a gyrus and give a confidence rating for both localizations. Interobserver agreement using kappa statistics and average confidence ratings were assessed to interpret the reported observations.
Results: Both the interobserver agreement and the confidence of the observers were greater for the integrated two-dimensional displays than for the two-dimensional SPECT display. An additional increase in agreement and confidence was seen with the integrated three-dimensional display.
Conclusion: Integrated display of SPECT and MR brain images provides better localization of cerebral blood perfusion abnormalities in the peripheral cortex in relation to the anatomy of the brain than single-modality display and increases the confidence of the observer.