Background: Coralline hydroxyapatite has been used since 1983 as volume replacement. Through 2001, a total of 200 hydroxyapatite implants were used in our department.
Objective: This prospective study was undertaken to measure the subjective and objective long-term tolerance of this implant.
Materials and methods: In 2012, a total of 20 patients were examined, who were enucleated or eviscerated between 1993 and 2001 (average follow-up 16.2 years) and had an hydroxyapatite implant placed with a scleral sheath. We evaluated the subjective tolerance and measured the motility, the prominence of the globe, lid positions, changes of the conjunctiva and postoperative complications.
Results: The subjective long-term tolerance was reported to be good. All patients had a ptosis; an ectropion was found in 50% of patients. In 40% of the patients additional surgery was performed. The motility was better in primary than in secondary placed implants. Volume replacement was successful in 10 patients, 9 patients had a retraction and 1 patient a prominent prosthesis.
Discussion: Hydroxyapatite implants with sclera sheathing were well tolerated and showed good motility on long-term follow-up over more than 16 years. Lid malpositions such as ptosis or ectropion are common but might be due to mechanical stress through the prosthesis and atrophy of the orbital fat.
Keywords: Anophthalmus; Compatibility; Hydroxyapatite orbital implant; Long-term results; Motility.