Clinical characteristics of and risk factors for hepatolithiasis developed after surgery for congenital biliary dilatation

Figure 1 Kaplan-Meier curve for postoperative hepatolithiasis occurrence.

Figure 2 Least absolute shrinkage and selection operator analysis for screening variables associated with postoperative hepatolithiasis. A: Least absolute shrinkage and selection operator coefficient profiles of seven variables. Variables: (1) Age at surgery; (2) Preoperative stone; (3) Preoperative symptoms; (4) Postoperative acute cholangitis; (5) Anastomotic leakage; (6) Todani type Ic relative to Ia; and (7) Todani type IV-A relative to Ia; B: Mean-square error with the 10-fold cross-validation method. The selection criterion for lambda was the one-standard-error rule. ¹Dotted vertical line was drawn at the optimal values using one standard error of the minimum criterion (1-SE rule).

Figure 3 The ability of age at surgery to predict the development of postoperative hepatolithiasis. A: Time-dependent receiver operating curve at 6 years after surgery. The area under the curve was 0.953. The cutoff age based on the Youden index was 31 years; B: Kaplan-Meier curve for hepatolithiasis stratified by age at surgery.