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Projection-Based Systems

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Corneal Topography

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Abstract

Projection-based topography systems include those using slit photography, rasterstereography, laser interferometry or moiré interference. An image is projected onto the surface of the cornea in the same way as a slide is projected onto a screen and viewed directly. Some of these systems have the advantage of obtaining data from irregular and non-reflective surfaces and potentially from a wider area of cornea. They directly measure corneal height (elevation), from which slope, curvature and power can be calculated. Corneal thickness (pachymetry) measurements can also be made by slit systems.

The projection-based technique most commonly used in commercial systems is slit photography, which gives an accuracy similar to other commercially available devices. However, the other techniques have potentially a higher accuracy and other advantages but need further development before being introduced to regular clinical practice.

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References

* References Particularly Worth Reading

  1. Warnicki JW, Rehkopf PG, Arrra RC, Stuart JC. Corneal topography using a projected grid. In: Schanzlin DJ, Robin JB, editors. Corneal topography. Measuring and modifying the cornea. New York: Springer; 1992. p. 25–32.

    Chapter  Google Scholar 

  2. Liang F-Q, Geasey SD, del Cerro Maquavella JV. A new procedure for evaluating smoothness of corneal surface following 193nm excimer laser ablation. Refract Corneal Surg. 1992;8:459–65.

    CAS  PubMed  Google Scholar 

  3. Ediger MN, Pettit GH, Weiblinger RP. Noninvasive monitoring of excimer laser ablation by time-resolved reflectometry. Refract Corneal Surg. 1993;9:268–75.

    CAS  PubMed  Google Scholar 

  4. Corbett MC, Verma S, Prydal JI, Pande M, Oliver KM, Patel S, Marshall J. The contribution of the corneal epithelium to the refractive changes occurring after excimer laser photorefractive keratectomy. Invest Ophthalmol Vis Sci. 1995;36:S2.

    Google Scholar 

  5. Mishima S. Some physiological aspects of the precorneal tearfilm. Arch Ophthalmol. 1965;73:233.

    Article  CAS  Google Scholar 

  6. Prydal JI, Campbell FW. Study of precorneal tear film thickness and structure by interferometry and confocal microscopy. Invest Ophthalmol Vis Sci. 1992;33:1996–2005.

    CAS  PubMed  Google Scholar 

  7. Naufal SC, Hess JS, Friedlander MH, Granet NS. Rasterstereography-based classification of normal corneas. J Cataract Refract Surg. 1997;23:222–30.

    Article  CAS  Google Scholar 

  8. Wilson SE, Klyce SD, Husseini ZM. Standardized color-coded maps for corneal topography. Ophthalmology. 1993;100:1723–7.

    Article  CAS  Google Scholar 

  9. *Auffarth GU, Tetz MR, Biazid Y, Völcker HE. Measuring anterior chamber depth with the Orbscan topography system. J Cataract Refract Surg. 1997;23(9):1351–5.

    Article  CAS  Google Scholar 

  10. Cairns G, Ormonde SE, Gray T, et al. Assessing the accuracy of the Orbscan II post LASIK: apparent keratectasia is paradoxically associated with anterior chamber depth reduction in successful procedures. Clin Exp Ophthalmol. 2005;33:147–52.

    Article  Google Scholar 

  11. Cairns G, McGhee CN. Orbscan computerised topography: attributes, applications and limitations. J Cataract Refract Surg. 2005;31:205–20.

    Article  Google Scholar 

  12. Hashemi H, Mehravaran S. Corneal changes after laser refractive surgery for myopia: comparison of Orbscan II and Pentacam findings. J Cataract Refract Surg. 2007;33:841–7.

    Article  Google Scholar 

  13. Prisant O, Calderon N, Chastang P, et al. Reliability of pachymetric measurements using Orbscan after excimer refractive surgery. Ophthalmology. 2003;110:511–5.

    Article  Google Scholar 

  14. Kamiya K, Oshika T, Amano S, et al. Influence of excimer laser PRK on the posterior corneal surface. J Cataract Refract Surg. 2000;26:867–71.

    Article  CAS  Google Scholar 

  15. Naroo SA, Charman WN. Changes in posterior corneal curvature after PRK. J Cataract Refract Surg. 2000;26:872–8.

    Article  CAS  Google Scholar 

  16. Seitz B, Torres F, Langenbucher A, et al. Posterior corneal curvature changes after myopic LASIK. Ophthalmology. 2001;108:666–72.

    Article  CAS  Google Scholar 

  17. Wang Z, Chen J, Yang B. Posterior corneal surface topography changes after LASIK are related to residual corneal bed thickness. Ophthalmology. 1999;106:406–9.

    Article  CAS  Google Scholar 

  18. Baek T, Lee K, Kagaya F, et al. Factors affecting the forward shift of posterior corneal surface after LASIK. Ophthalmology. 2001;108:317–20.

    Article  CAS  Google Scholar 

  19. Reinstein DZ, Silverman RH, Coleman J. High-frequency ultrasound measurement of the thickness of the corneal epithelium. Refract Corneal Surg. 1993;9:385–7.

    CAS  PubMed  Google Scholar 

  20. Reinstein DZ, Archer TJ, Gobbe M, Silverman RH, Coleman DJ. Epithelial thickness in the normal cornea: three-dimensional display with Artemis very high-frequency digital ultrasound. J Refract Surg. 2008;24(6):571–81.

    Article  Google Scholar 

  21. Warnicki JW, Rehkopf PG, Curtin DY, Burns SA, Arffa RC, Stuart JC. Corneal topography using computer analyzed rasterstereographic images. Appl Opt. 1988;27:1135–40.

    Article  CAS  Google Scholar 

  22. *Arffa RC, Warnicki JW, Rehkopf PG. Corneal topography using rastereography. Refract Corneal Surg. 1989;5:414–7.

    Google Scholar 

  23. *Belin MW, Litoff FK, Strods SJ, Winn SS, Smith RS. The PAR technology corneal topography system. Refract Corneal Surg. 1992;8:88–96.

    Google Scholar 

  24. Belin MW. Intraoperative raster photogrammetry – the PAR Corneal Topography System. J Cataract Refract Surg. 1993;19(Suppl):188–92.

    Article  Google Scholar 

  25. Belin MW, Zloty P. Accuracy of the PAR corneal topography system with spatial misalignment. CLAO J. 1993;19:64–8.

    CAS  PubMed  Google Scholar 

  26. Stultiens BAT, Jongsma FHM. Frequency modulation as an alternative for local phase in 3D corneal topography. Proc Ophthal Tech. 1994;2126:174–84.

    Google Scholar 

  27. Takeda M, Ina H, Kobayashi S. Fourier-transform method of fringe-pattern analysis for computer-based topography and interferometry. J Opt Soc Am. 1982;72:156–60.

    Article  Google Scholar 

  28. Corbett MC, O’Brart DPS, Stultiens BAT, Jongsma FHM, Marshall J. Corneal topography using a new moiré image-based system. Eur J Implant Ref Surg. 1995;7:353–70.

    Article  Google Scholar 

  29. *Jongsma FHM, Laan FC, Stultiens BATh. A moiré based corneal topographer suitable for discrete Fourier analysis. Proc Ophthal Tech. 1994;2126:185–92.

    Google Scholar 

  30. Kawara T. Corneal topography using moire contour fringes. Appl Opt. 1979;18:3675–8.

    Article  CAS  Google Scholar 

  31. Varner JR. Holographic and moiré surface contouring. In: Erf R, editor. Holographic non-destructive testing. New York: Academic Press; 1974. p. 105–47.

    Chapter  Google Scholar 

  32. Skolnick AA. New holographic process provides noninvasive, 3-D anatomic views. JAMA. 1994;271:5–8.

    Article  CAS  Google Scholar 

  33. *Smolek MK. Holographic interferometry of intact and radially incised human eye-bank corneas. J Cataract Refract Surg. 1994;20:277–86.

    Article  CAS  Google Scholar 

  34. Baker PC. Holographic contour analysis of the cornea. In: Masters BR, editor. Non-invasive diagnostic techniques in ophthalmology. New York: Springer-Verlag; 1990. p. 82–97.

    Chapter  Google Scholar 

  35. Kasprzak H, Kowalik W, Jaronski J. Inferometric measurements of fine corneal curvature. SPIE. 1994;2329:32–9.

    Google Scholar 

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Authors and Affiliations

  1. Imperial College Healthcare NHS Trust, London, UK

    Melanie Corbett

  2. University Hospital Coventry and Warwickshire, Coventry, UK

    Nicholas Maycock

  3. Manchester, UK

    Emanuel Rosen

  4. Department of Ophthalmology, St. Thomas Hospital, London, UK

    David O’Brart

Authors
  1. Melanie Corbett
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  2. Nicholas Maycock
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  3. Emanuel Rosen
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  4. David O’Brart
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Corbett, M., Maycock, N., Rosen, E., O’Brart, D. (2019). Projection-Based Systems. In: Corneal Topography. Springer, Cham. https://doi.org/10.1007/978-3-030-10696-6_3

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  • DOI: https://doi.org/10.1007/978-3-030-10696-6_3

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  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-10694-2

  • Online ISBN: 978-3-030-10696-6

  • eBook Packages: MedicineMedicine (R0)

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