Zusammenfassung
Der Keratokonus ist eine bilaterale, progrediente, nichtentzündliche Erkrankung der Hornhaut, die mit einer kegelförmigen kornealen Vorwölbung einhergeht, die zu einer zunehmenden Verdünnung der Hornhaut führt und dadurch eine progrediente Verschlechterung der Sehschärfe aufgrund eines zunehmenden irregulären Astigmatismus induziert. Zahlreiche Verfahren gestatten die geometrische Vermessung der Hornhaut, was als Grundlage für die Diagnostik des Keratokonus sowie die Therapieplanung für die refraktive Hornhautchirurgie dient. Aufgrund fehlender Messmöglichkeiten konnten Informationen über die korneale Biomechanik bislang aber nur aus Spenderhornhäuten in vitro erhalten werden. Die Entwicklung und klinische Anwendung moderner Apparate in den letzten Jahren hat es ermöglicht, die biomechanischen Eigenschaften der Hornhaut in vivo zu analysieren. Heutzutage ist es möglich, das individuelle biomechanische Verhalten der Hornhaut zu erfassen, um die Diagnostik des Keratokonus zu optimieren und die Sicherheit von hornhautrefraktiven Eingriffen noch weiter zu erhöhen.
Abstract
Keratoconus is a bilateral, progressive, non-inflammatory corneal degeneration characterized by a conical protrusion of the cornea which leads to marked corneal thinning thereby inducing severe visual impairment due to increasingly irregular astigmatism. Current corneal imaging technology provides an accurate anatomical and topographical analysis of the cornea which is the ‘gold standard for the diagnosis of keratoconus and preoperative screening in refractive surgery. Until recently evaluation of corneal biomechanics was feasible only in vitro as the technology required for in vivo analysis was not available. However, in recent years methods have been developed which enable an accurate in vivo analysis of corneal biomechanics thereby enhancing the early detection of keratoconus and improving the safety profile of corneal refractive procedures.
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Interessenkonflikt. Z. Gatzioufas und B. Seitz geben an, dass kein Interessenkonflikt besteht. Dieser Beitrag beinhaltet keine Studien an Menschen oder Tieren.
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Gatzioufas, Z., Seitz, B. Neues zur Biomechanik der Kornea beim Keratokonus. Ophthalmologe 110, 810–817 (2013). https://doi.org/10.1007/s00347-013-2818-x
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DOI: https://doi.org/10.1007/s00347-013-2818-x