Abstract
Purpose: :
Endophthalmitis is one of the the most devastating complications following keratoprosthesis (KPro) surgery. The Boston Type I KPro is comprised of a PMMA front plate and stem, a PMMA or titanium backplate, and a locking ring. These components are assembled with donor cadaveric corneal tissue between the front and back plate. The donor corneal button is then sutured to the recipient corneal bed. Integration of any KPro with recipient tissue is essential to avoid extrusion and to ensure a sealed, closed system that precludes microbial access into the anterior chamber. The ability to visualize corneal epithelial growth around and over the edge of the front plate would therefore be a reassuring sign for surgeons as it may act as a mechanical barrier to microbial ingress.
Methods: :
RTVue CAM (Optovue, Inc. Fremont, CA) spectral domain anterior segment OCT technology was utilized to image the anterior segment of five eyes of three patients with Boston Type I KPro from the Veterans Affairs Boston Healthcare System. The images were taken at various time points post-operatively (1 day to 6 years) and were retrospectively reviewed to assess the relationship between KPro PMMA front plate and donor corneal tissue.
Results: :
OCT Images of all 5 eyes demonstrated corneal epithelium extending from the donor corneal tissue and overriding the edge of the KPro front plate, a finding which was not always evident by slit-lamp examination. Serial imaging in the immediate post-operative period demonstrated this growth of epithelium as early as one week postoperatively.
Conclusions: :
Anterior Segment OCT is useful in demonstrating the presence of an epithelial lip extending from the donor corneal rim over the edge of the Boston Type I KPro front-plate. This protective lip appears to form as early as one week post-operatively, but cannot always be visualized clinically. The presence of such epithelial growth is reassuring as it suggests a tight seal and a barrier to infection.
Keywords: keratoprostheses • imaging/image analysis: clinical • wound healing