Abstract
Objective
To compare 10-year clinical outcomes of frozen versus fresh corneal graft carriers
for the Boston Keratoprosthesis type 1 (KPro).
Design
Prospective, non-masked randomized controlled trial.
Participants
Nineteen eyes of 19 patients having undergone Boston KPro type 1 implantation using
a fresh or frozen graft carrier.
Methods
All patients that underwent Boston KPro type 1 implantation by a single experienced
surgeon using an allograft carrier between October 2008 and March 2010 at the Centre
Hospitalier de l'Université de Montréal were considered. Patients were excluded if
they had a history of prior KPro implantation in the same eye. A subset of the patient
cohort enrolled in the initial study protocol of 24 months continued follow-up to
120 months. Participants were randomized to receive either a fresh or frozen corneal
graft carrier depending on tissue availability from the eye bank on the day of KPro
implantation.
Results
Nineteen eyes of 19 patients were included, with 11 in the fresh group and 8 in the
frozen group. At 10 years, in the fresh and frozen groups respectively, device retention
was 91% and 75%; mean best corrected visual acuity increased from counting fingers
preoperatively to 20/300 and 20/125; and incidence of complications per patient was
2.36 and 2.37. There were no statistically significant differences between groups
for any of these outcome measures (p > 0.05 for all analyses).
Conclusions
Fresh and frozen corneal graft carriers offer similar clinical outcomes for KPro implantation
in terms of device retention, change in visual acuity, and rate of complications at
10 years.
Résumé
Objectif
Examiner les résultats cliniques à 10 ans de l'implantation d'une kératoprothèse (KPro)
Boston de type 1 montée sur un greffon cornéen frais ou congelé.
Nature
Étude prospective, comparative, randomisée et sans insu.
Participants
Dix-neuf yeux de 19 patients qui ont reçu une KPro Boston de type 1 montée sur un
greffon cornéen frais ou congelé.
Résultats
Tous les patients qui ont reçu une KPro Boston de type 1 montée sur une allogreffe
aux mains d'un seul chirurgien d'expérience entre octobre 2008 et mars 2010 au Centre
hospitalier de l'Université de Montréal (CHUM) ont été pris en compte. Les patients
qui avaient déjà reçu une KPro dans le même œil ont été exclus. Un sous-groupe de
patients de la cohorte initiale qui avaient pris part à l’étude de 24 mois ont été
suivis pendant 120 mois. Les participants avaient reçu au hasard un support de greffon
cornéen frais ou congelé, selon la disponibilité des tissus à la banque oculaire le
jour même de l'implantation de la KPro.
Résultats
Dix-neuf yeux de 19 patients ont été inclus : 11 dans le groupe greffon frais et 8
dans le groupe greffon congelé. Voici les résultats à 10 ans dans les groupes greffon
frais et greffon congelé, respectivement : le taux de rétention de la prothèse se
chiffrait à 91 % et à 75 %; la meilleure acuité visuelle corrigée moyenne est passée
de la capacité de compter les doigts avant l'intervention pour atteindre 20/300 et
20/125; enfin, l'incidence de complications par patient s’élevait à 2,36 et à 2,37.
On n'a enregistré aucune différence statistiquement significative entre les groupes
en ce qui a trait à chacun de ces paramètres de mesure (p > 0,05 pour l'ensemble des
analyses).
Conclusions
Les supports de greffon cornéens frais ou congelés donnent des résultats cliniques
semblables dans l'implantation d'une KPro en ce qui a trait au taux de rétention de
la prothèse, à l'amélioration de l'acuité visuelle et au taux de complications à 10
ans.
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Article Info
Publication History
Published online: March 28, 2021
Footnotes
Oral presentations: American Society of Cataract and Refractive Surgery Virtual Annual Meeting, May 16–17, 2020; Canadian Ophthalmological Society Virtual Annual Meeting, June 25–28, 2020
Poster presentation: American Academy of Ophthalmology Virtual Annual Meeting, November 13–15, 2020
Identification
Copyright
© 2021 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.
