## 4 Discussion and Conclusions
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline  & \multicolumn{2}{c}{**Left Frontal Bone**} & \multicolumn{2}{c}{**Right Frontal Bone**} & \multicolumn{2}{c}{**Left Parietal Bone**} & \multicolumn{2}{c}{**Right Parietal Bone**} & \multicolumn{2}{c}{**Occipital Bone**} \\ \cline{2-10}  & **Reduction** & **Expansion** & **Reduction** & **Expansion** & **Reduction** & **Expansion** & **Reduction** & **Expansion** & **Reduction** & **Expansion** \\ \hline Severe & **3.87** & 1.68 & **4.14** & 1.24 & 1.34 & **4.48** & 0.97 & **5.68** & **6.06** & 0.88 \\ sagittal case & **3.41** & 1.00 & **3.65** & 0.90 & 1.06 & **2.84** & 0.62 & **3.99** & **2.62** & 0.65 \\ Severe bilateral & **5.38** & 3.11 & **5.83** & 2.62 & **6.34** & **6.36** & **5.37** & **6.81** & 0.13 & **12.78** \\ coronal case & **3.96** & 2.45 & **5.45** & 1.45 & **5.42** & 2.79 & 3.66 & **4.28** & 0.05 & **7.94** \\ Unilateral & 1.43 & **4.70** & **6.13** & 1.23 & 2.01 & **6.36** & **7.76** & 1.61 & 0.21 & **6.76** \\ Unilateral & 0.83 & **3.29** & 1.20 & **3.03** & 1.81 & **3.23** & **6.45** & 0.91 & 1.70 & **4.19** \\ \hline \end{tabular}
\end{table} 
Table 1: Results of the expansion and reduction indices of the regional cranial bones for representative synostoses of craniosynostosis. Bold indicates the major deformations of the surgical outcomes in each regional cranial bone. with an asymmetric shape, the right frontal and parietal bones showed a large reduction index, while the left frontal and parietal bones and occipital bone showed a large expansion index. In cases of unilateral lambdoid synostosis with an asymmetric shape, the right frontal and partial bones showed a large reduction index, and the left frontal and parietal bones and occipital bone showed a large expansion index. These large reduction indices indicated that the area of the regional bone was reduced after surgery, while these large expansion indices indicated that the area of the regional bone was expanded after surgery. Therefore, the proposed quantification method overcomes the limitation of quantification difficulty when using the traditional CI by analyzing regional cranial bones and providing useful information with which to quantify surgical effect for craniosynostosis patients with symmetric deformity as well as craniosynostosis patients with asymmetric deformity. Conceptualization, M.J.L. and H.H. ; methodology, M.J.L. and H.H. ; software, M.J.L. ; resources, K.W.S. ; writing--original draft preparation, M.J.L. ; writing--review and editing, H.H. and K.W.S. ; project administration, H.H. ; funding acquisition, H.H. All authors have read and agreed to the published version of the manuscript. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No.2017R1D1A1B03034927) and the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2020R1A2C1102140). The study was approved by the Institutional Review Board of Severance Hospital, Yonsei University College of Medicine, Seoul, Korea (4-2016-0603). Informed Consent Statement: Informed consent was waived from the IRB due to the retrospective nature of the study and the analysis using anonymous clinical data. Data Availability Statement: Not applicable. Conflicts of Interest: The authors declare no conflict of interest.