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Augenheilkunde up2date 2021; 11(04): 351-370
DOI: 10.1055/a-0642-1386
Bindehaut, Hornhaut, Lederhaut

Detektion des subklinischen Keratokonus

Detection of Subclinical Keratoconus
Stephan Degle
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Zusammenfassung

Das Frühstadium eines Keratokonus, ohne klassische und kennzeichnende klinische Befunde, stellt eine Kontraindikation für refraktive Chirurgie dar. Dieser Beitrag zeigt deshalb gemäß dem aktuellen Stand der Technik Möglichkeiten auf, Risikofaktoren für einen subklinischen Keratokonus zu erkennen.

Abstract

The early stage of a keratoconus (KC), without classic and characteristic clinical findings, is a contraindication for refractive surgery. This article therefore shows, in accordance with the current state of the art, ways of identifying risk factors for subclinical keratoconus.

After delimitation, this publication contains a current summary of epidemiology, etiology and pathophysiology of subclinical and clinical KC. Furthermore, an overview of different grading scales is given. A detailed description of several practical possibilities for detection of subclinical KC is the focus of this publication: typical abnormalities with subclinical KC in ocular aberrometry, corneal topography, Zernike analysis, Fourier analysis, indices of the corneal anterior surface; especially tomography of the anterior segment of the eye respecting addition of the corneal posterior surface and the pachymetry, and also innovative techniques counting in the rigidity or biomechanical properties, as well as traditional techniques giving hints for subclinical KC as retinoscopy, ophthalmoscopy and subjective refraction.

In preparation for refractive surgical interventions and to avoid possible consequences of subclinical KC, a suitable analysis with different methods should always be carried out in addition to a specific anamnesis. An exclusive consideration of the available indices is not sufficient, as this does not reveal early stages. Ideally, the biomechanics of the cornea is included in the diagnosis. The combination of tomography and biomechanics with methods of artificial intelligence are trendsetting in detection of subclinical KC.

Kernaussagen

  • Ziel der Erkennung des Keratokonus (KK) im subklinischen Stadium ist es, den Patienten frühzeitig über eine mögliche Progression und Komplikationen aufzuklären und diese zu minimieren.

  • Das Erkennen eines subklinischen Keratokonus ist vor refraktivchirurgischen Eingriffen von großer Bedeutung, um postoperative Komplikationen einer raschen Progression zu vermeiden.

  • Auch Patienten ohne einseitigen klinischen Keratokonus sollten vor refraktivchirurgischen Eingriffen auf Anzeichen von subklinischen Keratokonus untersucht werden.

  • Traditionelle Klassifikationen des klinischen Befunds sind für eine Früherkennung nicht geeignet.

  • Eine aberrometrische Auswertung der HOA (Aberrationen höherer Ordnung) und tomografische Verfahren, die Vorder- und Rückfläche und Dicke der Hornhaut berücksichtigen und diese mit Normwerten vergleichen, können subklinische Formen des Keratokonus detektieren. Speziell sind hier Differenzenvergleiche im Zeitverlauf zu empfehlen. Hilfreich sind ergänzend auch Hinweise aus der Anamnese, der subjektiven Bestimmung sowie der Skiaskopie und Ophthalmoskopie.

  • Die Kombination von Tomografie und Biomechanik mit Methoden der künstlichen Intelligenz sind in der Früherkennung von Keratokonus richtungsweisend.

Schlüsselwörter

subklinischer Keratokonus - Keratokonus-Klassifikation - Topografie - Tomografie - Rigidität der Hornhaut

Key words

subclinical keratoconus - keratoconus grading - topography - tomography - corneal biomechanics


Publication History

Article published online:
19 November 2021

© 2021. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 

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