Abstract
Purpose: :
The purpose of this study is to measure implant failure rates for alloplastic versus biointegrating materials. Additional attention has been paid to comparing failure rates of enucleations versus eviscerations as treatment modalities.
Methods: :
A comprehensive search was undertaken of all first enucleation and evisceration procedures performed at the DMC from 2005 to 2010. Data collected included type of procedure, implant material, number of failures, time to failure, and reason for failure. Exclusion criteria included non-native enucleation/evisceration (i.e. no re-ops), enucleation and implantation to reform the bony orbit (e.g. anophthalmic sockets), and an inability to identify implant type. Treatment failures were defined into four categories: implant exposure or extrusion, implant migration, socket contracture, and orbital infection or trauma requiring surgical revision. Data calculated included total follow-up time, time to failure, and average time to failure. Survival analyses of all data subsets were performed.
Results: :
A total of 126 enucleations and eviserations were evaluated on a single eye of 126 patients. Of these, 110 of were enucleations and 16 were eviscerations. A total of 69 alloplastic implants and 56 biointegrating implants were analyzed. The most common reasons for evisceration and enucleation was endophthalmitis and globe trauma respectively. The most common alloplastic and biointegrating implant was silicone and porous polyethylene respectively. Of 69 alloplastic implants, 8 failures occurred (11.6%). The average time to failure was 70.5 ± 93.2 days. Of 56 biointegrating implants, 2 failures occurred (3.6%). The average time to failure was 67.5 ± 34.6 days. Of 110 total enucleations, 10 failures occurred (9.1%). The average time to failure was 221.4 ± 528.4 days. Of 16 eviscerations, only 1 failure occurred (6.3%). The survival rate of all alloplastic implants was 88.4% versus 96.4% for all biointegrating implants (p = 0.11).
Conclusions: :
No statistically significant difference of implant failures between alloplastic and bio-integrated devices was appreciated in this study. As there was a trend towards increased survival rates with biointegrating implants (p ~ 0.11). A more powerful study may yet elucidate a statistically significant difference between these two materials. Analysis of reasons for chosen procedures showed that blind sequellae of ruptured globes as a reason for enucleation versus evisceration was highly prevalent and may be overrepresented compared to the general population.