International Ophthalmology

, Volume 39, Issue 11, pp 2467–2475 | Cite as

Assessment of total corneal power after myopic corneal refractive surgery in Chinese eyes

  • Yanjun HuaEmail author
  • Chao Pan
  • Qinmei WangEmail author
Original Paper



To develop a new regression formula based on the Gaussian thick lens formula and to verify the accuracy of the regression formula.


In this prospective study, 207 eyes of 207 myopic subjects and 133 eyes of 67 postoperative subjects were included. For the 133 postoperative eyes, 127 eyes underwent laser-assisted in situ keratomileusis, and 6 eyes underwent photorefractive keratectomy. Subjective refraction and Pentacam HR were performed preoperatively and postoperatively, and IOLMaster was performed in the postoperative group. SimK, keratometry based on the Gaussian optic formula (KGOF), KCHM obtained using the clinical history method, and the regression formulas KRF1 and KRF2 were calculated.


(1) A statistically significant difference (t = 155.164, P = 0.000) between SimK and KGOF of 1.24 ± 0.12 D was observed, and there was a good correlation between SimK and KGOF (r = 0.996, P = 0.000). The first regression formula (KRF1 = 0.351 + 1.021 × KGOF) was obtained using linear regression. (2) Statistically significant differences (t = 19.114, − 25.184, 4.702, and all P = 0.000) between SimK and KCHM, KGOF and KCHM and KRF1 and KCHM of 0.75 ± 0.45 D, 0.96 ± 0.44 D and 0.18 ± 0.43 D, respectively, were obtained. Good correlations between SimK and KCHM, KGOF and KCHM and KRF1 and KCHM (all r ≧ 0.977, all Ps = 0.000) were also observed. The regression formula (KRF2 = − 1.204 + 1.027 × KRF1) was obtained using linear regression. (3) Six methods were used for the prediction of IOL power in the postoperative group. The highest results were obtained from the Shammas formula (without preoperative data) combining Km (obtained by IOLMaster) followed by the KCHM and KRF2 combining Haigis formula. The third was obtained from the KCHM and KRF2 combining Hoffer Q formula; and the smallest was the Km combining Haigis formula.


The IOL power predicted by KRF2 in eyes after myopic CRS may be accurate.


Corneal refractive surgery Corneal power Intraocular lens power Keratometric index Pentacam HR 


Author contributions

Yanjun Hua wrote the main manuscript text. Chao Pan collected and analyzed data. Qinmei Wang revised the manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare no competing financial interests.


  1. 1.
    Feiz V (2010) Intraocular lens power calculation after corneal refractive surgery. Middle East Afr J Ophthalmol 17:63–68PubMedPubMedCentralGoogle Scholar
  2. 2.
    Kalyani SD, Kim A, Ladas JG (2008) Intraocular lens power calculation after corneal refractive surgery. Curr Opin Ophthalmol 19:357–362CrossRefGoogle Scholar
  3. 3.
    Hoffer KJ (2009) Intraocular lens power calculation after previous laser refractive surgery. J Cataract Refract Surg 35:759–765CrossRefGoogle Scholar
  4. 4.
    Patel S, Alio JL, Artola A (2008) Changes in the refractive index of the human corneal stroma during laser in situ keratomileusis. Effects of exposure time and method used to create the flap. J Cataract Refract Surg 34:1077–1082CrossRefGoogle Scholar
  5. 5.
    Leyland M (2004) Validation of Orbscan II posterior corneal curvature measurement for intraocular lens power calculation. Eye (Lond) 18:357CrossRefGoogle Scholar
  6. 6.
    Tang M, Chen A, Li Y, Huang D (2010) Corneal power measurement with Fourier-domain optical coherence tomography. J Cataract Refract Surg 36:2115–2122CrossRefGoogle Scholar
  7. 7.
    Goss DA, West RW (2002) Introduction to the optics of the Eye. Butterworth-Heinemann, Oxford, pp 113–135Google Scholar
  8. 8.
    Mandell KJ, Jurkunas UV, Pineda R 2nd (2010) Intraocular lens calculations after corneal refractive surgery. Int Ophthalmol Clin 50:181–189CrossRefGoogle Scholar
  9. 9.
    Fam HB, Lim KL (2007) Validity of the keratometric index: large population-based study. J Cataract Refract Surg 33:686–691CrossRefGoogle Scholar
  10. 10.
    Ho JD et al (2008) Validity of the keratometric index: evaluation by the Pentacam rotating Scheimpflug camera. J Cataract Refract Surg 34:137–145CrossRefGoogle Scholar
  11. 11.
    Crawford AZ, Patel DV, McGhee CN (2013) Comparison and repeatability of keratometric and corneal power measurements obtained by Orbscan II, Pentacam, and Galilei corneal tomography systems. Am J Ophthalmol 156:53–60CrossRefGoogle Scholar
  12. 12.
    Arce CG et al (2009) Calculation of intraocular lens power using Orbscan II quantitative area topography after corneal refractive surgery. J Refract Surg 25:1061–1074CrossRefGoogle Scholar
  13. 13.
    Jonuscheit S, Doughty MJ (2009) Repeatability of central corneal thickness measures by Orbscan pachymetry for right and left eyes. Eye Contact Lens 35:20–25CrossRefGoogle Scholar
  14. 14.
    Kawana K et al (2005) Central corneal thickness measurements using Orbscan II scanning slit topography, noncontact specular microscopy, and ultrasonic pachymetry in eyes with keratoconus. Cornea 24:967–971CrossRefGoogle Scholar
  15. 15.
    Falavarjani KG et al (2010) Determining corneal power using Pentacam after myopic photorefractive keratectomy. Clin Exp Ophthalmol 38:341–345CrossRefGoogle Scholar
  16. 16.
    Savini G, Barboni P, Carbonelli M, Hoffer KJ (2009) Agreement between Pentacam and videokeratography in corneal power assessment. J Refract Surg 25:534–538CrossRefGoogle Scholar
  17. 17.
    Kim SW, Kim EK, Cho BJ, Song KY, Kim TI (2009) Use of the pentacam true net corneal power for intraocular lens calculation in eyes after refractive corneal surgery. J Refract Surg 25:285–289CrossRefGoogle Scholar
  18. 18.
    Savini G, Barboni P, Profazio V, Zanini M, Hoffer KJ (2008) Corneal power measurements with the Pentacam Scheimpflug camera after myopic excimer laser surgery. J Cataract Refract Surg 34:809–813CrossRefGoogle Scholar
  19. 19.
    Huang D et al (1991) Optical coherence tomography. Science 254:1178–1181CrossRefGoogle Scholar
  20. 20.
    Wang X, Dong J, Wu Q (2014) Mean central corneal thickness and corneal power measurements in pigmented and white rabbits using Visante optical coherence tomography and ATLAS corneal topography. Vet Ophthalmol 17:87–90CrossRefGoogle Scholar
  21. 21.
    Hua Y, Huang J, Pan C, Wang Q (2012) Assessment of total corneal power and intraocular lens power in post-LASIK eyes. Natl Med J China 92:2339–2344Google Scholar
  22. 22.
    Wang L, Mahmoud AM, Anderson BL, Koch DD, Roberts CJ (2011) Total corneal power estimation: ray tracing method versus gaussian optics formula. Invest Ophthalmol Vis Sci 52:1716–1722CrossRefGoogle Scholar
  23. 23.
    Holladay JT, Van Gent S, Ting AC, Portney V, Willis TR (1989) Silicone intraocular lens power vs temperature. Am J Ophthalmol 107:428–429CrossRefGoogle Scholar
  24. 24.
    Borasio E, Stevens J, Smith GT (2006) Estimation of true corneal power after keratorefractive surgery in eyes requiring cataract surgery: BESSt formula. J Cataract Refract Surg 32:2004–2014CrossRefGoogle Scholar
  25. 25.
    Shammas HJ et al (2003) Correcting the corneal power measurements for intraocular lens power calculations after myopic laser in situ keratomileusis. Am J Ophthalmol 136:426–432CrossRefGoogle Scholar
  26. 26.
    Jin H, Auffarth GU, Guo H, Zhao P (2012) Corneal power estimation for intraocular lens power calculation after corneal laser refractive surgery in Chinese eyes. J Cataract Refract Surg 38:1749–1757CrossRefGoogle Scholar
  27. 27.
    Sharma R, Maharajan P, Kotta S, Maharajan S (2014) Prediction of refractive outcome after cataract surgery using partial coherence interferometry: comparison of SRK/T and Haigis formulae. Int Ophthalmol 34:451–455CrossRefGoogle Scholar
  28. 28.
    Eom Y, Kang SY, Song JS, Kim HM (2013) Use of corneal power-specific constants to improve the accuracy of the SRK/T formula. Ophthalmology 120:477–481CrossRefGoogle Scholar
  29. 29.
    Langenbucher A et al (2012) Individualization of IOL constants for two hydrophobic intraocular lenses. SRK II, SRK/T, Hoffer-Q, Holladay 1 and Haigis formula. Ophthalmologe 109:468–473CrossRefGoogle Scholar
  30. 30.
    Holladay JT, Hill WE, Steinmueller A (2009) Corneal power measurements using Scheimpflug imaging in eyes with prior corneal refractive surgery. J Refract Surg 25:862–868CrossRefGoogle Scholar
  31. 31.
    Holladay JT (2010) Accuracy of Scheimpflug Holladay equivalent keratometry readings after corneal refractive surgery. J Cataract Refract Surg 36:182–184CrossRefGoogle Scholar
  32. 32.
    Xu K, Hao Y, Qi H (2014) Intraocular lens power calculations using a Scheimpflug camera to measure corneal power. Biotech Histochem 89:348–354CrossRefGoogle Scholar
  33. 33.
    McCarthy M, Gavanski GM, Paton KE, Holland SP (2011) Intraocular lens power calculations after myopic laser refractive surgery: a comparison of methods in 173 eyes. Ophthalmology 118:940–944CrossRefGoogle Scholar
  34. 34.
    De Bernardo M, Capasso L, Caliendo L, Paolercio F, Rosa N (2014) IOL power calculation after corneal refractive surgery. Biomed Res Int 2014:658350CrossRefGoogle Scholar
  35. 35.
    Masket S, Masket SE (2006) Simple regression formula for intraocular lens power adjustment in eyes requiring cataract surgery after excimer laser photoablation. J Cataract Refract Surg 32:430–434CrossRefGoogle Scholar
  36. 36.
    Haigis W (2008) Intraocular lens calculation after refractive surgery for myopia: Haigis-L formula. J Cataract Refract Surg 34:1658–1663CrossRefGoogle Scholar
  37. 37.
    Peyman A, Peyman M (2009) Intraocular lens power after refractive surgery: Haigis-L formula. J Cataract Refract Surg 35:1650–1651CrossRefGoogle Scholar
  38. 38.
    Latkany RA et al (2005) Intraocular lens calculations after refractive surgery. J Cataract Refract Surg 31:562–570CrossRefGoogle Scholar

Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Department of OphthalmologyShanghai Jiao Tong University Affiliated Sixth People’s HospitalShanghaiChina
  2. 2.Aier Eye HospitalWuhanChina
  3. 3.School of Optometry and Ophthalmology and Eye HospitalWenzhou Medical UniversityWenzhouChina

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