Fig. 6
Kaplan–Meier survival analysis of experimental groups. (A) The control group; (B) the sham group; (C) the injection of HP alone group, 30-min dual-frequency sonication with Hp injection in (D) one repetition at the first day group (US(150 kHz + 1 MHz) + Hp)0; (E) two repetitions at the first and sixth days group (US(150 kHz + 1 MHz) + Hp)0,6; (F) three repetitions at the first, sixth, and twelfth days group (US(150 kHz + 1 MHz) + Hp)0,6,12; (G) four repetitions at the first, sixth, twelfth, and eighteenth days group (US(150 kHz + 1 MHz) + Hp)0,6,12,18; and (H) the fractional treatment group treated by 7.5-min dual-frequency sonication and Hp injection at the first, third, sixth, and ninth days (USfraction (150 kHz + 1 MHz) + Hp)0,3,6,9