Assessing Environmental Contamination During Corneal Processing

Authors

Thomas D. Miller, MS, CEBT, Andrew J. Maxwell, BA, CEBT, Paul J. Trizuto, BS, Mudassir Razvi BS, CEBT, Hortense Kendall BS, CEBT, Patricia Dahl, B.S., CEBT, Bernardino Iliakis, MHA CEBT

Keywords

endothelial keratoplasty; femtosecond laser-assisted keratoplasty; bacterial contamination; settle plates; processing; eye bank; laser suite; laminar flow hood.

Abstract

ABSTRACT

Purpose: This study was performed to assess the potential
introduction of biological contamination during eye bank processing
of corneal tissue, including femtosecond laser-assisted
keratoplasty (FLAK) and endothelial keratoplasty (EK) tissue.
The study was designed to determine if FLAK or EK processing
could be performed without introducing bioburden or environmental
contamination of the corneal tissue.

Methods: We evaluated the processing of FLAK tissue in a
laser processing suite and EK processing in a laminar flow hood,
following established Standard Operating Procedures (SOPs) for
FLAK and EK. In-process cultures were taken from corneoscleral
rims before and after tissue preparation using a femtosecond
laser. Environmental and processing cultures were also taken
from sterile soft contact lenses substituted for the corneoscleral
disc during EK processing before and after processing. Environmental
settling plates were taken before and after FLAK and EK
processing of the corneal tissue.

Results: The processing cultures taken from the corneoscleral
rims pre-and post-femtosecond laser processing and those cultures
taken of the sterile soft contact lenses pre-and post-simulated
femtosecond laser processing all resulted in no growth. The
sets of cultures taken of the sterile soft contact lenses pre-and
post-simulated EK processing resulted in no growth.

Conclusions: Results demonstrate that eye banks may reliably
provide contaminant free FLAK and EK corneal tissue processed
in an open-room or laminar flow hood. Aseptic technique as well
as industry accepted corneal decontamination with povidone iodine
and environmental monitoring are required. Sterile contact
lenses may be a valid substitute in simulated processing of the
corneoscleral disc during environmental and process validation
studies.