Figure 4.

Facial ROIs. ${\mathbf{R}}^1$, right forehead side; ${\mathbf{R}}^2$, left forehead side; ${\mathbf{R}}^3$, right periorbital side; ${\mathbf{R}}^4$, left periorbital side; ${\mathbf{R}}^5$, tip of nose; ${\mathbf{R}}^6$, right cheek; ${\mathbf{R}}^7$, left cheek; ${\mathbf{R}}^8$, right perinasal side; ${\mathbf{R}}^9$, left perinasal side; ${\mathbf{R}}^{10}$, right chin side; ${\mathbf{R}}^{11}$, left chin side.