Abstract
Background The blood-aqueous barrier (BAB) separates immunoprivileged tissue of the eye from
the blood circulation. Disruption of the BAB is therefore a risk factor for rejection
after keratoplasty.
Purpose The present work provides a review of the work of our group and others on BAB disruption
in penetrating and posterior lamellar keratoplasty and its implications for clinical
outcome.
Methods A PubMed literature search was performed to generate a review paper.
Results Laser flare photometry provides an objective and reproducible method to assess the
integrity of the BAB. Studies of the flare after penetrating and posterior lamellar
keratoplasty demonstrate a mostly regressive disruption of the BAB in the postoperative
course, which is influenced in extent and duration by multiple factors. Persistently
elevated flare values or an increase in flare after initial postoperative regeneration
may indicate an increased risk of rejection.
Discussion In case of persistent or recurrent elevated flare values after keratoplasty, intensified
(local) immunosuppression may potentially be useful. This could become important in
the future, especially for the monitoring of patients after high-risk keratoplasty.
Whether an increase of the laser flare is a reliable early indicator of an impending
immune reaction after penetrating or posterior lamellar keratoplasty has to be shown
in prospective studies.
Key words
keratoplasty - DMEK - tyndallometry - tyndall - flare - blood-aqueous barrier
