New perspectives on keratoconus as revealed by corneal confocal microscopy

REFERENCES

• Rabinowitz YS. Keratoconus. Surv Ophthalmol 1998; 42: 297–319.
   PubMed Web of Science ®Google Scholar
• Chopra I, Jain AK. Between eye asymmetry in keratoconus in an Indian population. Clin Exp Optom 2005; 88: 146–152.
   PubMedGoogle Scholar
• Haque S, Simpson T, Jones L. Corneal and epithelial thickness in keratoconus: a comparison of ultrasonic pachymetry, Orbscan II and optical coherence tomography. J Refract Surg 2006; 22: 486–493.
   PubMed Web of Science ®Google Scholar
• Patel DV, Mcghee CN. Contemporary in vivo confocal microscopy of the living human cornea using white light and laser scanning techniques: a major review. Clin Exp Ophthalmol 2007; 35: 71–88.
   PubMed Web of Science ®Google Scholar
• Efron N, Perez‐gomez I, Mutalib HA, Hollingsworth J. Confocal microscopy of the normal human cornea. Contact Lens Ant Eye 2001; 24: 16–24.
   Google Scholar
• Hollingsworth J, Perez‐gomez I, Mutalib HA, Efron N. A population study of the normal cornea using an in vivo, slit‐scanning confocal microscope. Optom Vis Sci 2001; 78: 706–711.
   PubMed Web of Science ®Google Scholar
• Zhivov A, Stave J, Vollmar B, Guthoff R. In vivo confocal microscopic evaluation of Langerhans cell density and distribution in the corneal epithelium of healthy volunteers and contact lens wearers. Cornea 2007; 26: 47–54.
   PubMed Web of Science ®Google Scholar
• Patel DV, Mcghee CN. Mapping of the normal human corneal sub‐basal nerve plexus by in vivo laser scanning confocal microscopy. Invest Ophthalmol Vis Sci 2005; 46: 4485–4488.
   PubMed Web of Science ®Google Scholar
• Böhnke M, Masters BR. Long‐term contact lens wear induces a corneal degeneration with microdot deposits in the corneal stroma. Ophthalmology 1997; 104: 1887–1896.
   PubMed Web of Science ®Google Scholar
• Parmar DN, Awwad ST, Petroll WM, Bowman RW, Mcculley JP, Cavanagh HD. Tandem scanning confocal corneal microscopy in the diagnosis of suspected acanthamoeba keratitis. Ophthalmology 2006; 113: 538–547.
   PubMed Web of Science ®Google Scholar
• Brasnu E, Bourcier T, Dupas B, Degorge S, Rodallec T, Laroche L, Borderie V, Baudouin C. In vivo confocal microscopy in fungal keratitis. Br J Ophthalmol 2006; 91: 588–591.
   Web of Science ®Google Scholar
• Krachmer JH, Feder RS, Belin MW. Keratoconus and related noninflammatory corneal thinning disorders. Surv Ophthalmol 1984; 28: 293–322.
   PubMed Web of Science ®Google Scholar
• Teng CC. Electron microscope study of the pathology of keratoconus: I. Am J Ophthalmol 1963; 55: 18–47.
   PubMed Web of Science ®Google Scholar
• Scroggs MW, Proia AD. Histopathological variation in keratoconus. Cornea 1992; 11: 553–559.
   PubMed Web of Science ®Google Scholar
• Sturbaum CW, Peiffer RL Jr. Pathology of corneal endothelium in keratoconus. Ophthalmologica 1993; 206: 192–208.
   Web of Science ®Google Scholar
• Sawaguchi S, Fukuchi T, Abe H, Kaiya T, Sugar J, Yue BY. Three‐dimensional scanning electron microscopic study of keratoconus corneas. Arch Ophthalmol 1998; 116: 62–68.
   PubMedGoogle Scholar
• Hollingsworth JG, Bonshek RE, Efron N. Correlation of the appearance of the keratoconic cornea in vivo by confocal microscopy and in vitro by light microscopy. Cornea 2005; 24: 397–405.
   PubMed Web of Science ®Google Scholar
• Hollingsworth JG, Efron N. Observations of banding patterns (Vogt striae) in keratoconus: a confocal microscopy study. Cornea 2005; 24: 162–166.
   Web of Science ®Google Scholar
• Hollingsworth JG, Efron N, Tullo AB. In vivo corneal confocal microscopy in keratoconus. Ophthalmic Physiol Opt 2005; 25: 254–260.
   PubMed Web of Science ®Google Scholar
• Hollingsworth JG, Efron N, Tullo AB. A longitudinal case series investigating cellular changes to the transplanted cornea using confocal microscopy. Contact Lens Ant Eye 2006; 29: 135–141.
   PubMedGoogle Scholar
• Zadnik K, Barr JT, Gordon MO, Edrington TB. Biomicroscopic signs and disease severity in keratoconus. Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study Group. Cornea 1996; 15: 139–146.
   PubMed Web of Science ®Google Scholar
• Perez‐gomez I, Hollingsworth J, Efron N. Effects of benoxinate hydrochloride 0.4% on the morphological appearance of the cornea using confocal microscopy. Contact Lens Ant Eye 2004; 27: 45–48.
   Google Scholar
• Somodi S, Hahnel C, Slowik C, Richter A, Weiss DG, Guthoff R. Confocal in vivo microscopy and confocal laser‐scanning fluorescence microscopy in keratoconus. Ger J Ophthalmol 1996; 5: 518–525.
   Google Scholar
• Wygledowska‐promienska D, Rokita‐wala I, Gierek‐ciaciura S, Piatek‐koronowska G. The alterations in corneal structure at III/IV stage of keratoconus by means of confocal microscopy and ultrasound biomicroscopy before penetrating keratoplasty. Klin Oczna 1999; 101: 427–432.
   Google Scholar
• Uçakhan OO, Kanpolat A, Ylmaz N, Özkan M. In vivo confocal microscopy findings in keratoconus. Eye Contact Lens 2006; 32: 183–191.
   PubMedGoogle Scholar
• Weed KH, Macewen CJ, Cox A, Mcghee CN. Quantitative analysis of corneal microstructure in keratoconus utilising in vivo confocal microscopy. Eye 2007; 21: 614–623.
   PubMed Web of Science ®Google Scholar
• Tsubota K, Mashima Y, Murata H, Sato N, Ogata T. Corneal epithelium in keratoconus. Cornea 1995; 14: 77–83.
   PubMed Web of Science ®Google Scholar
• Mocan MC, Irkec M. Fluorescein enhanced confocal microscopy in vivo for the evaluation of corneal epithelium. Clin Experiment Ophthalmol 2007; 35: 38–43.
   PubMed Web of Science ®Google Scholar
• Rokita‐wala I, Gierek‐ciaciura S, Majlinger R, Wygledowska‐promienska D. Iron deposits in cornea in confocal microscope. Klin Oczna 2001; 103: 111–115.
   Google Scholar
• Scroggs MW, Proia AD. Histopathological variation in keratoconus. Cornea 1992; 11: 553–539.
   PubMed Web of Science ®Google Scholar
• Aktekin M, Sargon MF, Cakar P, Celik HH, Firat E. Ultrastructure of the cornea epithelium in keratoconus. Okajimas Folia Anat Jpn 1998; 75: 45–53.
   Google Scholar
• Jongebloed WL, Worst JF. The keratoconus epithelium studied by SEM. Doc Ophthalmol 1987; 67: 171–181.
   Web of Science ®Google Scholar
• Chi HH, Katzin HM, Teng CC. Histopathology of keratoconus. Am J Ophthalmol 1956; 42: 847–860.
   Web of Science ®Google Scholar
• Tsubota K. In vivo observation of the corneal epithelium. Scanning 1994; 16: 295–299.
   Web of Science ®Google Scholar
• Tsubota K, Yamada M, Naoi S. Specular microscopic observation of human corneal epithelial abnormalities. Ophthalmology 1991; 98: 184–191.
   Web of Science ®Google Scholar
• Patel DV, Mcghee CN. Mapping the corneal sub‐basal nerve plexus in keratoconus by in vivo laser scanning confocal microscopy. Invest Ophthalmol Vis Sci 2006; 47: 1348–1351.
   PubMed Web of Science ®Google Scholar
• Patel DV, Mcghee CN. Contemporary in vivo confocal microscopy of the living human cornea using white light and laser scanning techniques: a major review. Clin Experiment Ophthalmol 2007; 35: 71–88.
   PubMed Web of Science ®Google Scholar
• Szaflik JP. Comparison of in vivo confocal microscopy of human cornea by white light scanning slit and laser scanning systems. Cornea 2007; 26: 438–445.
   PubMed Web of Science ®Google Scholar
• Auran JD, Koester CJ, Rapaport R, Florakis GJ. Wide field scanning slit in vivo confocal microscopy of flattening‐induced corneal bands and ridges. Scanning 1994; 16: 182–186.
   Web of Science ®Google Scholar
• Kobayashi A, Yokogawa H, Sugiyama K. In vivo laser confocal microscopy of Bowman’s layer of the cornea. Ophthalmology 2006; 113: 2203–2208.
   PubMed Web of Science ®Google Scholar
• Kaas‐hansen M. The histopathological changes of keratoconus. Acta Ophthalmol Scand 1993; 71: 411–414.
   Google Scholar
• Fini ME. Keratocyte and fibroblast phenotypes in the repairing cornea. Prog Retin Eye Res 1999; 18: 529–551.
   PubMed Web of Science ®Google Scholar
• Patel SV, Mclaren JW, Hodge DO, Bourne WM. Confocal microscopy in vivo in corneas of long‐term contact lens wearers. Invest Ophthalmol Vis Sci 2002; 43: 995–1003.
   PubMed Web of Science ®Google Scholar
• Erie JC, Patel SV, Mclaren JW, Nau CB, Hodge DO, Bourne WM. Keratocyte density in keratoconus. A confocal microscopy study. Am J Ophthalmol 2002; 134: 689–695.
   PubMed Web of Science ®Google Scholar
• Jalbert I, Stapleton F. Effect of lens wear on corneal stroma: preliminary findings. Aust NZ J Ophthalmol 1999; 27: 211–213.
   PubMedGoogle Scholar
• Efron N, Mutalib HA, Perez‐gomez I, Koh HH. Confocal microscopic observations of the human cornea following overnight contact lens wear. Clin Exp Optom 2002; 85: 149–155.
   PubMedGoogle Scholar
• Efron N, Perez‐gomez I, Morgan PB. Confocal microscopic observations of stromal keratocytes during extended contact lens wear. Clin Exp Optom 2002; 85: 156–160.
   PubMedGoogle Scholar
• Kallinikos P, Morgan P, Efron N. Assessment of stromal keratocytes and tear film inflammatory mediators during extended wear of contact lenses. Cornea 2006; 25: 1–10.
   PubMed Web of Science ®Google Scholar
• Kallinikos P, Efron N. On the etiology of keratocyte loss during contact lens wear. Invest Ophthalmol Vis Sci 2004; 45: 3011–3020.
   PubMed Web of Science ®Google Scholar
• Hollingsworth JG, Efron N. Confocal microscopy of the corneas of long‐term rigid contact lens wearers. Contact Lens Ant Eye 2004; 27: 57–64.
   Google Scholar
• Wilson SE, He YG, Weng J, Li Q, Mcdowall AW, Vital M, Chwang EL. Epithelial injury induces keratocyte apoptosis: hypothesized role for the interleukin‐1 system in the modulation of corneal tissue organization and wound healing. Exp Eye Res 1996; 62: 325–327.
   PubMed Web of Science ®Google Scholar
• Kim WJ, Rabinowitz YS, Meisler DM, Wilson SE. Keratocyte apoptosis associated with keratoconus. Exp Eye Res 1999; 69: 475–481.
   PubMed Web of Science ®Google Scholar
• Fabre EJ, Bureau J, Pouliquen Y, Lorans G. Binding sites for human interleukin 1 alpha, gamma interferon and tumor necrosis factor on cultured fibroblasts of normal cornea and keratoconus. Curr Eye Res 1991; 10: 585–592.
   PubMed Web of Science ®Google Scholar
• Tuori AJ, Virtanen I, Aine E, Kalluri R, Miner JH, Uusitalo HM. The immunohistochemical composition of corneal basement membrane in keratoconus. Curr Eye Res 1997; 16: 792–801.
   PubMed Web of Science ®Google Scholar
• Møller‐pedersen T, Li HF, Petroll WM, Cavanagh HD, Jester JV. Confocal microscopic characterization of wound repair after photorefractive keratectomy. Invest Ophthalmol Vis Sci 1998; 39: 487–501.
   PubMed Web of Science ®Google Scholar
• Møller‐pedersen T, Cavanagh HD, Petroll WM, Jester JV. Stromal wound healing explains refractive instability and haze development after photorefractive keratectomy: a 1‐year confocal microscopic study. Ophthalmology 2000; 107: 1235–1245.
   PubMed Web of Science ®Google Scholar
• Ohno K, Mitooka K, Nelson LR, Hodge DO, Bourne WM. Keratocyte activation and apoptosis in transplanted human corneas in a xenograft model. Invest Ophthalmol Vis Sci 2002; 43: 1025–1031.
   PubMed Web of Science ®Google Scholar
• Daxer A, Fratzl P. Collagen fibril orientation in the human corneal stroma and its implication in keratoconus. Invest Ophthalmol Vis Sci 1997; 38: 121–129.
   PubMed Web of Science ®Google Scholar
• Maurice DM. The structure and transparency of the cornea. J Physiol 1957; 136: 263–286.
   PubMed Web of Science ®Google Scholar
• Simo mannion L, Tromans C, O’donnell C. An evaluation of corneal nerve morphology and function in moderate keratoconus. Contact Lens Ant Eye 2005; 28: 185–192.
   PubMedGoogle Scholar
• Simo mannion L, Tromans C, O’donnell C. Corneal nerve structure and function in keratoconus: A case report. Eye Contact Lens 2007; 33: 106–108.
   Google Scholar
• Brookes NH, Loh IP, Clover GM, Poole CA, Sherwin T. Involvement of corneal nerves in the progression of keratoconus. Exp Eye Res 2003; 77: 515–524.
   PubMed Web of Science ®Google Scholar
• Komai Y, Ushiki T. The three‐dimensional organization of collagen fibrils in the human cornea and sclera. Invest Ophthalmol Vis Sci 1991; 32: 2244–2258.
   PubMed Web of Science ®Google Scholar
• Freund DE, Mccally RL, Farrell RA, Cristol SM, L’hernault NL, Edelhauser HF. Ultrastructure in anterior and posterior stroma of perfused human and rabbit corneas. Relation to transparency. Invest Ophthalmol Vis Sci 1995; 36: 1508–1523.
   PubMed Web of Science ®Google Scholar
• Morishige N, Wahlert AJ, Kenney MC, Brown DJ, Kawamoto K, Chikama T, Nishida T, Jester JV. Second‐harmonic imaging microscopy of normal human and keratoconus cornea. Invest Ophthalmol Vis Sci 2007; 48: 1087–1094.
   PubMed Web of Science ®Google Scholar
• Stachs O, Bochert A, Gerber T, Koczan D, Thiessen HJ, Guthoff RF. The extracellular matrix structure in keratoconus. Ophthalmologe 2004; 101: 384–389.
   Web of Science ®Google Scholar
• Hayes S, Boote C, Tuft SJ, Quantock AJ, Meek KM. A study of corneal thickness, shape and collagen organisation in keratoconus using videokeratography and X‐ray scattering techniques. Exp Eye Res 2007; 84: 423–434.
   PubMed Web of Science ®Google Scholar
• Tripathi RC, Bron AJ. Secondary anterior crocodile shagreen of Vogt. Br J Ophthalmol 1975; 59: 59–63.
   Web of Science ®Google Scholar
• Dangel ME, Kracher GP, Stark WJ. Anterior corneal mosaic in eyes with keratoconus wearing hard contact lenses. Arch Ophthalmol 1984; 102: 888–890.
   Google Scholar
• Meek KM, Blamires T, Elliott GF, Gyi TJ, Nave C. The organisation of collagen fibrils in the human corneal stroma: a synchrotron X‐ray diffraction study. Curr Eye Res 1987; 6: 841–846.
   PubMed Web of Science ®Google Scholar
• Katz HH. A hypothesis for the formation of vertical corneal striae as observed in the wearing of softlens contact lenses and in keratoconus. Am J Optom Physiol Opt 1976; 53: 420–421.
   Google Scholar
• Smolek MK, Mccarey BE. Interlamellar adhesive strength in human eyebank corneas. Invest Ophthalmol Vis Sci 1990; 31: 1087–1095.
   PubMed Web of Science ®Google Scholar
• Smolek MK. Interlamellar cohesive strength in the vertical meridian of human eye bank corneas. Invest Ophthalmol Vis Sci 1993; 34: 2962–2969.
   PubMed Web of Science ®Google Scholar
• Mcmahon TT, Robin JB, Scarpulla KM, Putz JL. The spectrum of topography found in keratoconus. CLAO J 1991; 17: 198–204.
   PubMedGoogle Scholar
• Laing RA, Sandstrom MM, Berrospi AR, Leibowitz HM. The human corneal endothelium in keratoconus: A specular microscopic study. Arch Ophthalmol 1979; 97: 1867–1869.
   PubMed Web of Science ®Google Scholar
• Matsuda M, Suda T, Manabe R. Quantitative analysis of endothelial mosaic pattern changes in anterior keratoconus. Am J Ophthalmol 1984; 98: 43–49.
   PubMed Web of Science ®Google Scholar
• Halabis JA. Analysis of the corneal endothelium in keratoconus. Am J Optom Physiol Opt 1987; 64: 51–53.
   Google Scholar
• Hoffer KJ, Kraff MC. Normal endothelial cell count range. Ophthalmology 1980; 87: 861–866.
   Web of Science ®Google Scholar
• Esgin H, Erda N. Endothelial cell density of the cornea during rigid gas permeable contact lens wear. CLAO J 2000; 26: 146–150.
   Google Scholar
• Grupcheva CN, Craig JP, Sherwin T, Mcghee CN. Differential diagnosis of corneal oedema assisted by in vivo confocal microscopy. Clin Experiment Ophthalmol 2001; 29: 133–137.
   PubMed Web of Science ®Google Scholar
• Alsuhaibani AH, Sutphin JE, Wagoner MD. Confocal microscopy of subepithelial infiltrates occurring after epidemic keratoconjunctivitis. Cornea 2006; 25: 778–780.
   Google Scholar
• Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet‐a‐induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol 2003; 135: 620–627.
   PubMed Web of Science ®Google Scholar
• Mazzotta C, Traversi C, Baiocchi S, Sergio P, Caporossi T, Caporossi A. Conservative treatment of keratoconus by riboflavin‐UVA‐induced cross‐linking of corneal collagen: qualitative investigation. Eur J Ophthalmol 2006; 16: 530–535.
   PubMed Web of Science ®Google Scholar
• Mazzotta C, Balestrazzi A, Traversi C, Baiocchi S, Caporossi T, Tommasi C, Caporossi A. Treatment of progressive keratoconus by riboflavin‐UVA‐induced cross‐linking of corneal collagen: Ultrastructural analysis by Heidelberg Retinal Tomograph II in vivo confocal microscopy in humans. Cornea 2007; 26: 390–397.
   PubMed Web of Science ®Google Scholar
• Ruckhofer J. Clinical and histological studies on the intrastromal corneal ring segments (ICRS(R), Intacs(R)). Klin Monatsbl Augenheilkd 2002; 219: 557–574.
   PubMed Web of Science ®Google Scholar
• Kymionis GD, Siganos CS, Tsiklis NS, Anastasakis A, Yoo SH, Pallikaris AI, Astyrakakis N, Pallikaris IG. Long‐term follow‐up of Intacs in keratoconus. Am J Ophthalmol 2007; 143: 236–244.
   PubMed Web of Science ®Google Scholar
• Shi W, Xie L, Li S, Yuan F, Liu H. Observation on healing process of corneal lens after epikeratophakia with confocal microscopy. Zhonghua Yan Ke Za Zhi 2002; 38: 295–297.
   Google Scholar
• Imre L, Resch M, Nagymihaly A. In vivo confocal corneal microscopy after keratoplasty. Ophthalmologe 2005; 102: 140–146.
   Web of Science ®Google Scholar
• Niederer RL, Perumal D, Sherwin T, Mcghee CN. Corneal innervation and cellular changes after corneal transplantation: an in vivo confocal microscopy study. Invest Ophthalmol Vis Sci 2007; 48: 621–626.
   PubMed Web of Science ®Google Scholar
• Forseto ados S, Dos santos MS, Sampaio A, Mascaro V, Nosé W. Diagnosis of epithelial ingrowth after penetrating keratoplasty with confocal microscopy. Cornea 2006; 25: 1124–1127.
   Web of Science ®Google Scholar