Post-op PTA average: 6 months 36, 47 dB, 12 months 37, 33 dB and 24 months 37, 98 dB lower than pre-operative PTA 49, 7 dB; 70, 1% PTA ≤ 40 dB after 6 months Post-op ABG average: 6 months 20, 11 dB, 12 months 21, 7 dB and 24 months 22, 9 dB lower than pre-operative ABG 35, 03 dB; 58, 2% ABG ≤ 20 dB after 6 months.