DIFFICULTIES WITH HYDROXYAPATITE ORBITAL IMPLANTS IN 2 PATIENTS WITH DYSFUNCTIONAL LEVATOR SUPERIOR RECTUS MUSCLE COMPLEX

Hydroxyapatite orbital implants are recognized for their excellent res ults in anophthalmos. Few complications are reported in the literature . We implanted hydroxyapatite spheres in two patients with acquired an ophthalmos and denervated or nonfunctional levator palpebrae superiori s and superior rectus muscles. In both patients, the implant rotated a nteriorly, obliterating the superior fornix and causing proptosis. Pro sthetic fitting was impeded, necessitating surgical revision in both p atients. A hydroxyapatite implant may rotate and migrate anteriorly in the presence of a nonfunctional superior rectus muscle, distorting th e conjunctival fornices and causing proptosis. This complication calls into question whether muscle-attached orbital implants should be used in patients with significant rectus muscle weakness.