Taylor and colleagues have developed a prototype software system for vascular surgery planning using computational methods for modeling blood flow [75]. This system, the Advanced Surgical Planning Interactive Research Environment (ASPIRE) was developed using the Java programming language and the Virtual Reality Modeling Language. A typical treatment planning session starts by examining a case presentation. Patient history, medical imaging data and vascular lab data are examined through a web browser. The next step in the treatment planning process is the specification of a treatment plan and involves drawing a treatment on a sketchpad as shown in Figure 11. The sketch is referenced to a three-dimensional computer model reconstructed from
medical imaging data. In the present case circular and elliptical curves were fitted to magnetic resonance angiography (MRA) imaging data to extract the luminal surface of the blood vessels. Recently, a geometric segmentation technique, the level set method, has been employed to create patient specific models [76, 77]. Once a treatment plan is created, the next step is to predict the changes in blood flow which result from this treatment. The user submits the treatment to the system for evaluation and computational fluid dynamics calculations are used to compute the three-dimensional flow field and store the information in the system database.The user interface is then operated in the treatment evaluation mode to query the solution and examine the predicted flow distribution and pressure data using graphical means or three-dimensional visualizations.