The facial recess approach was used in 3 patients with CC malformation with an incomplete basal turn, and the transmastoid single-slit labyrinthotomy approach in 18 patients with classic CC malformation. After follow-up for 36 months, the average free-field hearing threshold was higher, and the scores for the CAP, SIR, IT-MAIS, and closed-set/open-set auditory speech perception tests were lower than in the control group (p < 0.05).