The Intermountain Healthcare catheter angiography annotation application (aka Angiographer) is designed to allow doctors to document the diagnosis and intervention process during an angiography procedure. The minimally invasive test involves inserting a catheter through the femoral artery into the heart. A contrast material is introduced into the bloodstream to clearly delineate the coronary arterial structure when exposed to x-rays. A number of animated images are retrieved from various camera orientations. The diagnostic portion consists of graphing the patient’s arterial pathways including any blockage or lesions. The intervention portion includes optionally placing stents in arteries to ensure continued blood flow. Currently, doctors are required to document this procedure using pen and paper on a flat schematic diagram.

The Angiographer application developed by InterKnowlogy addresses the inherent limitations of a traditional pen and paper approach by presenting the doctor with an interactive pen based display containing a three dimensional model of a heart and coronary arteries. Since each patient has a slightly different geometry to their coronary pathways, the doctor begins by using intuitive stylus-based gestures to modify a statistically average arterial template. X-ray images are presented in thumbnail form on a panel in the main application window. Clicking on an x-ray animates the orientation of the 3D heart model to align the model with the position and angle of the camera. This enhanced workflow provides a significant reduction to the overall duration and cost of the procedure. Once the basic structure has been laid out, the doctor can then annotate areas of blockage (lesions) using simple drawing tools and contextual pop-up diagnostic tools. Finally, the placement and result of intervention techniques such as stents can easily be marked on the three dimensional arterial structure.

Angiographer is built on the Windows Presentation Foundation and leverages the managed 3D functionality to animate the heart as well as the built-in tablet/ink integration to build gesture recognition features. Coronary arteries are rendered as actual three dimensional spline extrusions as the user moves the stylus across the surface of the heart. Despite containing well over fifty thousand triangles, the heart models rotates smoothly even on average graphics processors. Angiographer also makes extensive use of WPF’s vector graphics engine and control styling to create an unique immersive interface that is simple to use yet still visually compelling.