**5. Case report using our system**

**Figure 18.** Vessel representation. The system displays coronary arteries as two parallel lines and handles the branches appropriately (a). The system first draws a wide red line (b1), and then a narrow white line inside (b2). The width of

The pulling interface deforms the curve while maintaining its local details (Figure 5 (c)) [13]. The system first generates triangles by connecting sets of three neighboring points on a polyline. As the user pulls a point along the curve, the system determines the location of free vertices so as to minimize the distortion of the triangles. We also used the peeling interface introduced in [13] to adjust the size of the region to be deformed, so that a larger area is de‐ formed as the user pulls more. As the user pulls the curve further away, the influence region

**Figure 19.** We use the pulling and peeling interface introduced in [13]. As the user pulls the curve further away, the

these lines decreases toward the non-connected end of a vessel to represent the taper (c1, c2).

**4.2. Geometry editing**

378 Artery Bypass

grows (Figure 19, left to right).

influence region grows (left to right).

We illustrate the effectiveness of our system, utilizing two cases of coronary artery bypass surgery as examples. These examples were only described (not illustrated) in the original papers.

The first example is Case 1 of [14]. The paper describes it as follows:

`A man, 45 years of age, had suffered attacks of angina pectoris during many years. He had had infarction of the myocardi‐ um. During the operation it was noted that the left coronary artery and the initial portions of its main branches were calci‐ fied. We also noted density of the right coronary artery. Anastomosis was applied between the inner thoracic artery and the circumflex branch of the left coronary artery.'

**Figure 20.** Case 1 of the report [14] using our system.

Figure 20 shows how to illustrate this process using our system. First, the user inputs a CAG table, as shown in Figure 20 (a). With our system, the user can set the type of the corre‐ sponding stenosis, as shown in the CAG table. The system then automatically generates a graphical coronary schema, as shown in Figure 20 (b). Figure 20 (c) shows the result of set‐ ting the severity of a stenosis of the left coronary artery to 100%.

**6. Discussion**

play.

the following benefits:

Our current implementation is a research prototype and is not yet being used in clinical practice. However, we have already demonstrated it to medical professionals and confirmed

Generating Graphical Reports on Cardiac Catheterization

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

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**1.** The user can easily modify the geometry of coronary arteries for individual patients.

**2.** The system can store the data compactly using vectors instead of bitmaps, which signif‐ icantly improves the network response when storing information on a remote server. **3.** The system can export the CAG table based on the AHA committee report in XML for‐ mat. Therefore, the system can easily exchange data with other existing systems.

**4.** The user can edit a coronary schema while viewing a reference image on the same dis‐

**5.** The user can draw diagrams and text freely in our system, which allows the recording

In addition, we received the following comment from another heart surgeon: `This is a userfriendly system. It is particularly effective for inexperienced doctors. Diagnosis is performed

The correspondence between a diagnosis and a dissection, as well as comparison be‐ tween the diagnosis and a CT scan image, are important to a surgeonpreparing for an operation. However, even though there is an AHA standard that defines how to verbal‐ ize diagnosis results, there is significant variation in the way surgeons describe diagnosis results, even among experts. Accordingly, one specialist commented that it is useful to have a link between CT scan images of the circumflex branches to the corresponding lo‐ cations in the schema. The specialist also commented that two-dimensional (2D) repre‐ sentation is sufficient if the purpose of the target system is diagnosis, but 3D

An issue with the current implementation is that it is limited by the AHA standards. The manner of recording schemas for cardiac catheterization varies widely among users and fa‐ cilities. As the AHA committee report was designed more than 30 years ago, it cannot han‐ dle many cases well. Therefore, a more powerful and flexible representation is needed.

We developed an effective interface for reporting graphical findings in cardiac catheteriza‐ tion using hand-drawn diagrams. The user can easily record the position and degree of a stenosis on a coronary schema template, and can also record treatments such as bypasses and stents. Once a bypass is added, the system automatically displays the resumption of blood flow. This type of automatic adaptation is not possible with paper-based medical re‐

by a heart physician. But, I think that it is useful also for a young surgeon's training. '

of new anomalies that have never been previously observed.

representation is desirable for training purposes.

**7. Conclusion and future work**

The bypass connects an open vessel to the closed coronary artery, and the system automati‐ cally opens the closed coronary artery to indicate that blood flow is recovered, as shown in Figure 20 (d, e).

The second example is Case 3 of the report [14]. The paper describes it as follows:

`A male patient (40 years of age), had suffered from generalized atherosclerosis. (…) During the operation calcification and complete occlusion of the initial portion of both branches of the left coronary artery were found. An end-to-end

anastomosis between the inner thoracic and interventricular arteries was made.'

**Figure 21.** Case 3 of the report [14] using our system.

Figure 21 shows how to illustrate this process using our system. First, the user inputs a CAG table, as shown in Figure 21 (a). The system then automatically generates a graphical coro‐ nary schema, as shown in Figure 21 (b). By default, the system automatically generates the stenosis in the middle portion of the corresponding vessel, as shown in Figure 21 (b). The user can move the stenosis to the initial portion, as shown in Figure 21 (c). Figure 21 (d) shows the result of setting the severity of the stenosis to 100%.

The bypass connects an open vessel to the closed coronary artery, and the system automati‐ cally opens the closed coronary artery to indicate that blood flow is recovered, as shown in Figure 21 (e, f) and (g, h).
