An incision is made in the ear canal near the ear drum. The ear drum is then carefully raised and the ear surgeon uses the operating microscope to see the structures in detail:

The middle ear is now opened. The bones of hearing are evaluated, confirming the surgeon's diagnosis of otosclerosis.

The calcium deposit is usually visible, and the stapes bone is tested. It does not move when pressed. The stapes bone is now separated from the incus (anvil.)

Freed from the stapes, the incus and malleus (hammer) bones can now move when pressed. A laser or other micro instrument vaporizes the tendon and the arch of the stapes bone, and the stapes bone remnant is removed from the middle ear.

The window that joins the middle ear to the inner ear and which serves as a platform for the stapes bone, is now opened. With a very low power setting, the laser is directed at the window and a miniscule opening (.6 mm or 1/40") is made.

Once the opening is made in the window, the artificial bone (prosthesis) is placed onto the incus bone and gently inserted. The prosthesis is then clipped gently onto the incus and the new assembly is gently pressed to confirm that its movement is correct. A piece of fat or other tissue is taken from a small incision behind the ear lobe and used to help seal the hole in the window and the space around the prosthesis.

The ear drum is then folded back into its normal position
and held down with a small gelatin sponge.