Fig. 3.1
Color-coding scheme for segments of the heart. Segmented pieces include aorta (red), coronary arteries (neutral), pulmonary veins and left atrium (pink), left ventricle (salmon), right ventricle (purple), right atrium and systemic veins (light blue), pulmonary arteries (dark blue), and trachea (yellow). Notice that right-sided structures are variations of blue (deoxygenated blood) and left-sided structures are variations of red (oxygenated blood). This is the same color scheme followed in most anatomy textbooks.
Fig. 3.2
The individual structures are then pieced together to create a full color-coded 3D model. IVC—inferior vena cava; SVC—superior vena cava.
We tested our color-coding scheme using three groups of 40 third-year medical students to identify basic anatomy using our scheme versus a randomly chosen color-coding scheme and models with no color added (Fig. 3.3) . Students were asked to identify 12 structures on their model: aorta, main pulmonary artery, right and left pulmonary arteries, right and left coronary arteries, inferior vena cava, superior vena cava, right and left atria, and right and left ventricles. With no color added, the 40 students identified an average of 2.5/12 structures correctly. With random color assigned to the anatomy, 40 students identified 5.3/12 structures correctly. Finally, with our color-coding scheme, 40 students identified 6.6/12 structures correctly. The difference in the number identified correctly between the random color group and our color group was statistically significant (P value of 0.001).
Fig. 3.3
Three different color-coding schemes for 3D models of the heart. (a) Our color coding scheme. (b) A random color scheme. (c) A model left in neutral color.
3.2 Patient-Specific Physical Models
Once the segmentation and coloring of the models is accomplished, the data can be used to create an actual 3D resin model of the anatomy. A 3D rapid prototyping machine can be used to create color-coded models of the heart. 3D models have a variety of applications for presurgical planning. These models are to scale and can be sterilized and used in the operating room (Figs. 3.4–3.6).
