The Two Piece (Magnetic) Ocular Prosthesis
 

When the eyelids are firm (caused by radiation, chemical or adhesions) and unresponsive to expansion it is not possible to insert a macrosize prosthesis into a skin grafted socket.  And, it is not the intention to compromise by placing a less than adequate size prosthesis (just for easier insertion) into the cavity, because it would negate any chance of obtaining near symmetrical palpebral fissures.  The weight of the prosthesis would not be a factor.  The only alternative is to fabricate the ovate prosthesis in two parts.  The posterior half of the elongated sphere would have a small magnet embedded near its anterior juncture, where it would join with the adjacent magnet on the posterior section of the front portion of the prosthesis.

Figure 25A The two-piece prosthesis when separated shows the magnets embedded (in clear acrylic).  The posterior half is marked for its position placement in the cavity.

Figure 25B The profile view of the two halves indicate the depth of the socket.  Note: Most skin grafted sockets follow the concave curvature of the bony orbital wall.

Figure 25C The posterior half of the prosthesis is shown in its position. Note: the almost leather-like firmness of the lower eyelid.

Figure 25D The completed prosthesis in frontal gaze.  Cosmetic optics would correct the slightly narrower horizontal aperture, and tinted lenses would detract from the immobile prosthetic eye.