**1. Introduction**

Electronic medical recording systems [1-4] have become widespread due to the improve‐ ment in hardware performance and user interfaces. Some recent systems are designed to support doctor–patient communication using a tablet PC [5-6]. However, usability is still an issue and medical professionals need more such user-friendly interfaces. To make these sys‐ tems accessible to inexperienced users and to reduce the overhead of data entry, we have been developing various pen-based electronic medical recording systems [7-8]. Pen-based computing is an active research area for both user interfaces and computer graphics. Our work is based on recent advances in this area, especially the freeform user interfaces pro‐ posed by Igarashi [9]. Using this approach, the user draws freehand lines on the screen as‐ sisted by the system, and the result is directly stored as a vector image. Our systems feature special purpose functions for pen input including three-dimensional (3D) sketching, useridentification, and handwritten character recognition and search [8]. They are designed to help medical professionals to think more freely when working on difficult problems without being constrained by cumbersome interfaces.

One problem with these freeform pen-based systems, however, is that their output does not easily fit into a structure that lends itself to further machine processing or interface with oth‐ er more traditional recording systems. Our goal in the project was to bridge this gap be‐ tween freeform diagramming and more structured recording.

One strength of pen-based systems is that they make it easy to draw and add diagrams to medical records. This is particularly useful in ophthalmology, otolaryngology, and dentistry in which diagrams play an important role in medical records. Indeed, the frequent use of

© 2013 Igarashi et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

diagrams makes it difficult to use traditional GUI-based medical recording systems in these areas [10]. Cardiac catheterization is one of these areas in which the diagram is an indispen‐ sable tool for medical recording. Existing electronic medical recording systems rely on struc‐ tured templates, but it is difficult to create an appropriate report of findings or treatment plan using these predefined templates. Most existing diagram editors are implemented as bitmap paint tools, not vector graphics. This makes it difficult to edit the geometry after‐ ward and requires that a large amount of data be transmitted and stored

We therefore developed a pen-based interface for graphical reporting of findings in cardiac catheterization (Figure 1) [11]. Figure 2 shows an illustration of the human heart. The target of our system is the coronary arteries. Figure 3 shows a screenshot of our system. The user can freely "sketch" coronary arteries and stenoses on the screen using a pen on a template of coronary features. The location and degree of each stenosis, and various treatments such as bypass and stents, are visually represented. We developed an algorithm that can extract se‐ mantic information from the graphical representation and store it in XML format. The sys‐ tem can also generate a table in the format specified in the AHA (American Heart Association) committee report [12]. This system is useful not only as a tool for efficiently generating reports of findings but also as an effective explanation tool for patients.

**Figure 2.** An illustration of the human heart. The target of our system is the coronary arteries (the red vessels shown in

Generating Graphical Reports on Cardiac Catheterization

http://dx.doi.org/10.5772/54235

369

this figure).

**Figure 3.** Recording an example of cardiac catheterization.

**Figure 1.** A screenshot of our system in use.

**Figure 2.** An illustration of the human heart. The target of our system is the coronary arteries (the red vessels shown in this figure).

**Figure 3.** Recording an example of cardiac catheterization.

diagrams makes it difficult to use traditional GUI-based medical recording systems in these areas [10]. Cardiac catheterization is one of these areas in which the diagram is an indispen‐ sable tool for medical recording. Existing electronic medical recording systems rely on struc‐ tured templates, but it is difficult to create an appropriate report of findings or treatment plan using these predefined templates. Most existing diagram editors are implemented as bitmap paint tools, not vector graphics. This makes it difficult to edit the geometry after‐

We therefore developed a pen-based interface for graphical reporting of findings in cardiac catheterization (Figure 1) [11]. Figure 2 shows an illustration of the human heart. The target of our system is the coronary arteries. Figure 3 shows a screenshot of our system. The user can freely "sketch" coronary arteries and stenoses on the screen using a pen on a template of coronary features. The location and degree of each stenosis, and various treatments such as bypass and stents, are visually represented. We developed an algorithm that can extract se‐ mantic information from the graphical representation and store it in XML format. The sys‐ tem can also generate a table in the format specified in the AHA (American Heart Association) committee report [12]. This system is useful not only as a tool for efficiently

generating reports of findings but also as an effective explanation tool for patients.

**Figure 1.** A screenshot of our system in use.

ward and requires that a large amount of data be transmitted and stored

368 Artery Bypass
