Iatrogene Keratektasie – eine Übersicht

Zusammenfassung

Die iatrogene Keratektasie ist eine der schwerwiegendsten postoperativen Komplikationen nach komplikationsloser refraktiver Hornhautlaserchirurgie. Die ektatischen Veränderungen können sich bereits 1 Woche oder auch erst viele Jahre nach der Operation entwickeln. Die tatsächliche aktuelle Inzidenz ist unklar, soll zwischen 0,04 und 2,8 % liegen. Die Keratektasie geht einher mit einer zunehmenden astigmatischen Myopisierung, einer Sehverschlechterung und Bildverzerrungen. Risikofaktoren sind neben einer dünnen Hornhaut < 500 µm eine pathologische Hornhauttopografie, eine geringe residuelle Stromadicke < 300 µm, eine hohe Myopie > 8 dpt, ein junges Lebensalter < 25 J., Neurodermitis, Familienanamnese bez. Keratokonus und Bindegewebserkrankungen sowie auch LASIK-Nachkorrekturen. Bei Erkennen und Diagnosesicherung durch Topografiekontrollen ist ein Crosslinking mittels Riboflavin/UVA-Licht mit späterer Kontaktlinsenanpassung indiziert. In seltenen Fällen ist heutzutage noch eine perforierende, besser eine tiefe lamelläre Keratoplastik erforderlich.

Abstract

Iatrogenic corneal ectasia is a rare complication but also one of the most feared situations that can occur after uneventful corneal laser surgery. Ectatic changes can occur as early as 1 week or can be delayed up to several years after LASIK. The actual incidence of ectasia is undetermined, an incidence rate of 0.04 to almost 2.8 % has been reported. Ectasia is most common following LASIK; however, cases have been reported following PRK and other corneal refractive procedures. Keratectasia shows progressive myopia, irregular astigmatism, ghosting, fluctuating vision and problems with scotopic vision. The progression leads to severe loss of corrected visual acuity. Risk factors are thin corneas < 500 µm, a pathological corneal topography, a residual stromal bed < 300 µm, high myopia > 8 D, young (female) age < 25 years, atopic dermatitis, allergies, family history for keratokonus and collagen diseases and retreatments. Treatment of choice is a cross-linking with riboflavin/UVA light with contact lenses. In severe cases a penetrating or a deep anterior lamellar graft is necessary.

Schlüsselwörter

Kornea - refraktive Chirurgie - LASIK - iatrogene Keratektasie - Crosslinking

Key words

cornea - refractive surgery - LASIK - iatrogenic keratectasia - cross-linking

• Literatur

• 1 Seiler T. Refraktive Chirurgie der Hornhaut. Stuttgart: Thieme; 2000
• 2 Barraquer JI. Method of cutting lamellar grafts in frozen corneas. New orientations for refractive surgery. Arch Soc Am Ophthalmol 1958; 1: 237-243
• 3 Barraquer JI. Keratomileusis for myopia and aphakia. Ophthalmol 1981; 88: 701-708
• 4 Waring GO, Lynn MJ, McDonnell PJ. Results of the prospective evaluation of radial keratotomy (PERK) study 10 years after surgery. Arch Ophthalmol 1994; 112: 1298-1308
• 5 Kohlhaas M, Draeger J, Schwartz R et al. Stabilität der Hornhautkrümmung nach radiärer Keratotomie – Eine Erklärung der progressiven Hyperopisierung?. Ophthalmo-Chirurgie 1992; 4: 193-197
• 6 Pallikaris I, Siganos D. Excimer laser in situ keratomileusis and photorefractive keratectomy. J Refract Corneal Surg 1994; 145: 498-510
• 7 Seiler T, Quurke AW. Iatrogenic keratectasia after LASIK in a case of forme fruste keratoconus. J Cataract Refract Surg 1998; 24: 1007-1009
• 8 Parmar D, Claoué C. Keratectasia following excimer laser photorefractive keratectomy. Acta Ophthalmol Scand 2004; 82: 102-105
• 9 Randleman JB, Banning CS, Stulting RD. Corneal ectasia after hyperopic LASIK. J Refract Surg 2007; 2: 98-102
• 10 Pallikaris IG, Kymionis GD, Astryrakakis NI. Corneal ectasia induced by laser in situ keratomileusis. J Cataract Refract Surg 2001; 27: 1796-1802
• 11 Randleman JB, Russell B, Ward MA et al. Risk factors and prognosis for corneal ectasia after LASIK. Ophthalmology 2003; 110: 267-275
• 12 Condon PI. Will keratectasia be a major complication for LASIK in the long term?. J Cataract Refract Surg 2006; 32: 2124-2132
• 13 Tabbara KF, Kotb AA. Risk factors for corneal ectasia after Lasik. Ophthalmology 2006; 113: 1618-1622
• 14 Binder PS. Analysis of ectasia after laser in situ keratomileusis: risk factors. J Cataract Refract Surg 2007; 33: 1530-1538
• 15 Condon PI, OʼKeefe M, Binder PS. Long-term results of laser in situ keratomileusis for high myopia: risk for ectasia. J Cataract Refract Surg 2007; 33: 583-590
• 16 Randleman JB, Woodward M, Lynn MJ et al. Risk assessment for ectasia after corneal refractive surgery. Ophthalmology 2008; 115: 37-50
• 17 Hafezi F, Iseli HP. Pregnancy-related exacerbation of iatrogenic keratectasia despite corneal collagen crosslinking. J Cataract Refract Surg 2008; 34: 1219-1221
• 18 Woodward M, Randleman JB, Russell B et al. Visual rehabilitation and outcomes for ectasia after corneal refractive surgery. J Cataract Refract Surg 2008; 34: 383-388
• 19 Ambrosio RJ, Randleman JB. Screening for ectasia risk: what are we screening for and how should we screen for it?. J Refract Surg 2013; 29: 230-232
• 20 Wollensak J, Buddecke E. Biochemical studies on human corneal proteoglycans – a comparison of normal and keratoconic eyes. Graefes Arch Clin Exp Ophthalmol 1990; 228: 517-523
• 21 Meek KM, Tuft SJ, Huang Y et al. Changes in collagen orientation and distribution in keratoconus corneas. Invest Ophthalmol Vis Sci 2005; 46: 1948-1956
• 22 Rohrbach JM, Szurmann P, El-Wardani M et al. Zur Häufigkeit der exzessiven Verdickung der epithelialen Basalmembran beim Keratokonus. Klin Monatsbl Augenheilkd 2006; 223: 889-893
• 23 Andreassen TT, Simonsen AH, Oxlund H. Biomechanical properties of keratoconus and normal corneas. Exp Eye Res 1980; 31: 435-441
• 24 Luce DA. Determining in vivo biomechanical properties of the cornea with an ocular response analyzer. J Cataract Refract Surg 2005; 31: 156-162
• 25 Roberts CJ, Dupps WJ. Biomechanics of corneal ectasia and biomechanical treatments. J Cataract Refract Surg 2014; 40: 991-998
• 26 Solomon KD. Flap thickness accuracy. Comparision of 6 microkeratome models. J Cataract Refract Surg 2004; 30: 964-977
• 27 Kohlhaas M, Spoerl E, Speck A et al. Eine neue Behandlung der Keratektasie nach LASIK durch Kollagenvernetzung mit Riboflavin/UVA-Licht. Klin Monatsbl Augenheilkd 2005; 222: 430-436
• 28 Kohlhaas M, Spoerl E, Speck A et al. Behandlung der Keratektasie nach LASIK durch Hornhautvernetzung. Ophthalmo-Chirurgie 2006; 18: 327-338
• 29 Spoerl E, Mrochen M, Sliney D et al. Safety of UVA-riboflavin cross-linking of the cornea. Cornea 2007; 26: 385-389
• 30 Hafezi F, Kanellopoulos J, Wiltfang R et al. Corneal collagen crosslinking with riboflavin and ultraviolet A to treat induced keratectasia after laser in situ keratomileusis. J Cataract Refract Surg 2007; 33: 2035-2040
• 31 Brooks NO, Greenstein SA, Fry K et al. Patient subjective visual function after corneal collagen crosslinking for keratoconus and corneal ectasia. J Cataract Refract Surg 2012; 38: 615-619
• 32 Greenstein SA, Fry KL, Hersh MJ et al. Higher-order aberrations after corneal collagen crosslinking for keratoconus and corneal ectasia. J Cataract Refract Surg 2012; 38: 292-302
• 33 Richoz O, Mavrakanas N, Pajic B et al. Corneal collagen cross-linking for ectasia after LASIK and photorefractive keratectomy: long-term results. Ophthalmology 2013; 120: 1354-1359
• 34 Greenstein SA, Hersh PS. Characteristics influencing outcomes of corneal collagen crosslinking for keratoconus and ectasia: Implications for patient selection. J Cataract Refract Surg 2013; 39: 1133-1140
• 35 Hersh PS, Greenstein SA, Fry KL. Corneal collagen cross-linking for keratoconus and corneal ectasia: one-year results. J Cataract Refract Surg 2011; 37: 149-160
• 36 Yildirim A, Cakir H, Kara N et al. Corneal collagen crosslinking for ectasia after laser in situ keratomileusis: long-term results. J Cataract Refract Surg 2014; 40: 1591-1596
• 37 Vinciguerra P, Camesasca FI, Albe E et al. Corneal collagen cross-linking for ectasia after excimer laser refractive surgery: 1-year results. J Refract Surg 2010; 26: 486-497
• 38 Wittig-Silva C, Chan E, Islam F et al. A randomized, controlled trial of corneal collagen cross-linking in progressive keratoconus. Ophthalmology 2014; 121: 812-821
• 39 Seiler T, Hafezi F. Corneal cross-linking induced stromal demarcation line. Cornea 2006; 25: 1057-1059
• 40 Jordan C, Patel DV, Abeysekera N et al. In vivo microscopy analyses of corneal microstructural changes in a prospective study of collagen cross-linking in keratoconus. Ophthalmology 2014; 121: 469-474
• 41 Tomita M, Yoshida Y, Yamamoto Y et al. In vivo confocal microscopy of morphologic changes after simultaneous LASIK and accelerated collagen crosslinking for myopia: One year results. J Cataract Refract Surg 2014; 40: 981-990
• 42 Kontadakis GA, Kymionis GD, Kankariya VP et al. Effect of collagen cross-linking on corneal innervation, corneal sensitivity and tear function of patients with keratoconus. Ophthalmology 2013; 120: 917-922
• 43 Pinero DP, Alcon N. In vivo charaterization of corneal biomechanics. J Cataract Refract Surg 2014; 40: 870-887
• 44 Spoerl E, Terai N, Scholz F et al. Detction of biomechanical changes after corneal cross-linking using ocular response analyzer software. J Refract Surg 2011; 27: 452-457