wwall: Safer for White may be 18.Qh4
After 18...Bxd7 19.exd7+ Kxd7 20.Qe8+ Kc7 21.Re7+ Qxe7 (not 21...Kb6?? 22.Qd8 mate) 22.Qxe7+ Nd7 23.Be6 Rd8 24.f3 and the win is much harder for White.
Better may be 19...b5, since 20.Bb3?? leads to mate after 20...Qf1+ 21.Rxf1 Rxf1 mate. If 20.Bxb5, then 20...Bxd7 21.exd7+ Kxd7 22.Qe7+ Kc8 and Black may be winning. 19...Bxd7 fails to 20.exd7+ Kxd7 21.Rd1+ Kc7 22.Qe7+ Kb6 23.Rb1+ Ka5 24.Qb4 mate.
After 20.Qe5, White is threatening 21.Rd8+ Kxd8 22.e7+ Ke8 23.Qh8+, leading to mate. If 20...Rf8 21.Red1 wins. If 20...Rxc4, then 21.Qh8+ Qf8 22.Rd8+, winning. If 20...Qxe1+, then 21.Qxe1 Rxc4 22.Rf7, threatening 23.Qe5 and 24.Qh8 mate.