Explantation Of Small-Aperture Corneal Inlays In Presbyopic Eyes: A Long Term Follow

The purpose of this study was to report explantation rate, reasons for the explantation and visual prognosis after explantation of a small-aperture corneal inlay used for the treatment of presbyopia.

This is a retrospective case series conducted at a single site in Salzburg, Austria, Paracelsus Medical University, Department of Ophthalmology and Optometry.

Medical records of 51 patients who had received a small-aperture corneal inlay ACI 7000 (KAMRA™, AcuFocus Inc., Irvine, CA, USA) between 2006-2009 were reviewed. Patients who had undergone explantation of the device were identified. Uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), were measured pre-implantation, post-implantation, pre-explantation, and post-explantation of the inlay. 

18 eyes from 18 patients were included in this study. The explantation rate was 35.3 % over 16 years, with blurry vision as the most common complaint. After explantation, none of the patients achieved pre-implantation UDVA. All patients had residual donut-shaped corneal haze in the stroma at the previous position of the inlay. All patients experienced improvement in haze none of them experiencing complete resolution. The degree of stromal haze was not related to the duration of implantation. 

 

Histopathology was performed in three cases. Histology and immunohistochemistry showed fibrohistiocytic reaction, fibroblasts and inflammatory cells like lymphocytes and granulocytes. 

Although this device is removeable, long-term monitoring is important, to detect late severe adverse events and signs of activation. The current model of this inlay is probably associated with fewer adverse events, but regular monitoring is nevertheless required. Patients should expect some post-explantation changes such as residual haze with a small subset experiencing persistent deficits in CDVA.