Crosslinking und Keratokonus

Zusammenfassung

Ein Keratokonus führt zu einer progressiven Vorwölbung und Verdünnung der Hornhaut. Um dies aufzuhalten, kann ein Crosslinking durchgeführt werden. Dabei ist eine Behandlung nach dem „Dresdener Protokoll“ eine effektive und sichere Behandlungsmöglichkeit, aber auch zahlreiche neue Anwendungsprotokolle (akzeleriertes Crosslinking, transepitheliales Crosslinking) und sogar weitere Indikationen (refraktive Eingriffe, infektiöse Keratitis) wurden in den letzten Jahren veröffentlicht.

Abstract

Keratoconus leads to a progressive protrusion and thinning of the cornea. In order to stop this, corneal crosslinking can be performed if the progression of the disease is proven. Crosslinking according to the “Dresden protocol” includes abrasion of the corneal epithelium, application of riboflavin eye drops and irradiation with UV-A light of an intensity of 3 mW/cm² for 30 minutes. The efficacy has been shown in several prospective randomized studies. One of the more recent developments is accelerated crosslinking, which allows a shorter irradiation time. On the other hand, the possibility of transepithelial crosslinking was presented, which does not require an abrasion of the cornea. This should reduce the occurrence of postoperative pain. The range of indications has also been expanded. Corneal crosslinking is used for post-LASIK keratectasia as well. It is also being considered for use in infectious keratitis. Topographically controlled crosslinking can likewise be used to try to positively influence the refractive power of the cornea. The risks of crosslinking include the occurrence of pain, haze or scarring, endothelial cell damage and, rarely, the occurrence of keratitis.

Kernaussagen

• Der Keratokonus führt zu einer fortschreitenden Vorwölbung und Verdünnung der Hornhaut. Um dies aufzuhalten, kann bei nachgewiesener Progression der Erkrankung ein Crosslinking durchgeführt werden.

• Das Crosslinking nach dem „Dresdener Protokoll“ umfasst die Abrasio des Hornhautepithels, die Applikation von Riboflavin-Augentropfen und die Bestrahlung mit UV-A-Licht einer Intensität von 3 mW/cm² über 30 min. Die Wirksamkeit wurde in mehreren prospektiven randomisierten Studien gezeigt.

• Zu den neueren Entwicklungen zählt zum einen das akzelerierte Crosslinking, bei dem eine kürzere Bestrahlungszeit möglich ist.

• Zum anderen wurde die Möglichkeit des transepithelialen Crosslinking präsentiert, bei dem eine Abrasio der Hornhaut nicht durchgeführt werden muss. Dieses Vorgehen soll das Auftreten von postoperativen Schmerzen reduzieren.

• Auch das Indikationsspektrum hat sich erweitert: Korneales Crosslinking wird auch bei Keratektasie nach LASIK eingesetzt. Ebenso wird die Anwendung bei der infektiösen Keratitis erwogen.

• Durch topografiegesteuertes Crosslinking kann versucht werden, die Brechkraft der Hornhaut positiv zu beeinflussen.

• Zu den Risiken des Crosslinking zählen

  • das Auftreten von Schmerzen,

  • Haze- bzw. Narbenbildung,

  • Endothelzellschäden und

  • selten das Auftreten einer Keratitis.

Schlüsselwörter

Keratokonus - Crosslinking - Kornea

Key words

keratoconus - crosslinking - cornea

Publication History

Article published online:
19 April 2021

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