Coronary Artery Center-Line Extraction Using Second Order Local Features

Figure 5

Geometric representation of the process for updating the tracing direction: (1) the first next point 𝑞^𝑘₀ is found on semicircular profile based on maximum vesselness value; (2) the vessel direction ^→𝑢^𝑘₀ is estimated and two linear profiles 𝑃_𝐿 and 𝑃_𝑅 are drawn at 𝑞^𝑘₀ perpendicular to ^→𝑢^𝑘₀; (3) two edge points 𝑒^𝑘_𝐿 and 𝑒^𝑘_𝑅 are detected and the final position of the next center-line point 𝑞^𝑘₁ is calculated; (4) the final tracing direction ^→𝑢^𝑘₁ is updated according to the updated center-line point 𝑞^𝑘₁.