Skip to main content

Advertisement

Log in

Accuracy of a new photorefractometer in young and adult patients

Graefe's Archive for Clinical and Experimental Ophthalmology Aims and scope Submit manuscript

Abstract

Background

Photorefraction can be carried out in both eyes simultaneously from a distance and is therefore suitable for examination of children. This study evaluated the accuracy of a commercially available photorefractometer (PowerRefractor, Plusoptix, Erlangen, Germany) and investigated whether the working distance relaxes the accommodation sufficiently without cycloplegia.

Methods

Photorefractometer readings were compared to cycloplegic retinoscopy. Because of the limited working range the group of patients consisted of low and moderate ametropic eyes within a spherical power of −7.0 to +5.0 D. One hundred and ninety-two eyes from 104 patients (2–81 years) were photorefracted under cycloplegia. A subgroup of 83 eyes from 46 patients was additionally refracted without cycloplegia.

Results

Under cycloplegia, the PowerRefractor measured the spherical equivalent slightly below that of cycloplegic retinoscopy (too much minus). The mean difference in spherical equivalent was −0.12±0.91 D (SD). The mean difference of cylindrical power was −0.17±0.73 D. The mean weighted axis difference was 0.61±0.71 D which is comparable to an axis deviation of 18° at a cylinder power of 1.00 D. Without cycloplegia, the mean difference of the spherical equivalent was −0.73±1.25 D. The mean difference of cylindrical power was −0.20±0.65 D. The mean weighted axis difference was 0.44±0.58 D which is comparable to an axis deviation of 13° at a cylinder power of 1.00 D.

Conclusions

Without cycloplegia, the spherical equivalent of the PowerRefractor tends to be underestimated due to uncontrolled accommodation, especially in children. Cycloplegia improves the accuracy in evaluating the spherical equivalent, but decreases the accuracy of cylinder power and axis.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4

References

  1. Althaus K, Bischoff P (1994) Videorefraktionsmessung im ersten Lebensjahr. Klin Monatsbl Augenheilkd 205:133–137

    Google Scholar 

  2. Atkinson J, Braddick OJ, Bobier B, Anker S, Ehrlich D, King J, Watson P, Moore A (1996) Two infant vision screening programmes: prediction and prevention of strabismus and amblyopia from photo- and videorefractive screening. Eye 10:189–198

    Google Scholar 

  3. Bobier WR, Braddick OJ (1985) Eccentric photorefraction: optical analysis and empirical measures. Am J Optom Physiol Opt 62:614–620

    Google Scholar 

  4. Bobier WR, Campbell MCW, McCreary CR, Power AM, Yang KC (1992) Geometrical optical analysis of photorefractive methods. Ophthal Physiol Opt 12:147–152

    Google Scholar 

  5. Choi M, Weiss S, Schaeffel F, Seidemann A, Howland HC, Wilhelm B, Wilhelm H (2000) Laboratory, clinical, and kindergarten test of a new eccentric infrared photorefractor (PowerRefractor). Optom Vis Sci 77:537–548

    Article  Google Scholar 

  6. Cronje S, Harris WF (1997) Short-term keratometric variation in the human eye. Optom Vis Sci 74:420–424

    Google Scholar 

  7. Grimm W (1981) Automatische objective Refraktionsbestimmung. DOZ 37:23–34

    Google Scholar 

  8. Hodi S, Wood ICJ (1994) Comparison of the techniques of videorefraction and static retinoscopy in the measurement of refractive error in infants. Ophthal Physiol Opt 14:20–24

    Google Scholar 

  9. Howland HC, Howland B (1974) Photorefraction: a technique for study of refractive state at a distance. J Opt Soc Am 64:240–249

    Google Scholar 

  10. Howland HC (1985) Optics of photoretinoscopy: results from ray tracing. Am J Optom Physiol Opt 62:621–625

    Google Scholar 

  11. Hsu-Winges C, Hamer RD, Norcia AM, Wesemann H, Chan C (1989) Polaroid photorefractive screening of infants. J Pediatr Ophthalmol Strabismus 26:254–260

    Google Scholar 

  12. McBrien NA, Millodot M (1987) The relationship between clinically measured tonic accommodation and refractive error. Invest Ophthalmol Vis Sci 28:997–1004

    CAS  PubMed  Google Scholar 

  13. Mohindra I (1975) A technique for infant vision examination. Am J Optom Physiol Opt 52:867–870

    Google Scholar 

  14. Owens DA, Mohindra I, Held R (1980) The effectiveness of a retinoscope beam as an accommodative stimulus. Invest Ophthalmol Vis Sci 19:942–949

    Google Scholar 

  15. Raasch TW, Schechtman KB, Davis LJ, Zadnik K (2001) Repeatability of subjective refraction in myopic and keratoconic subjects; results of vector analysis; CLEK Study Group. Ophthalmic Physiol Opt 21:376–383

    Article  Google Scholar 

  16. Rassow B, Wesemann W (1984) Automatic infrared refractors–1984b. Ophthalmology 91(suppl):10–26

    Google Scholar 

  17. Rosenfield M (1989) Evaluation of clinical techniques to measure tonic accommodation. Optom Vis Sci 66:809–814

    Google Scholar 

  18. Rosenfield M, Chiu NN (1995) Repeatability of subjective and objective refraction. Optom Vis Sci 72:577–579

    Google Scholar 

  19. Schimitzek T, Krzizok T (2001) Messungenauigkeit der Videorefraktometrie bei höheren Ametropien. Klin Monatsbl Augenheilkd 218:438–444

    Article  Google Scholar 

  20. Schimitzek T, Wesemann W (2002) Clinical evaluation of refraction using handheld wavefront autorefractor in young and adult patients. J Cataract Refract Surg 28:1655–1666

    Article  Google Scholar 

  21. Schimitzek T, Haase W (2002) Efficiency of a video-autorefractometer used as a screening device for amblyogenic factors. Graefe’s Arch Clin Exp Ophthalmol 240:710–716

    Google Scholar 

  22. Thompson A, Li T, Peck LB, Howland HC, Counts R, Bobier WR (1996) accuracy and precision of the Tomey ViVA infrared photorefractor. Optom Vis Sci 73:644–652

    Google Scholar 

  23. Twelker JD, Mutti DO (2001) Retinoscopy in infants using a near noncycloplegic technique, cycloplegia with tropicamide 1%, and cycloplegia with cyclopentolate 1%. Optom Vis Sci 78:215–222

    Article  Google Scholar 

  24. Wesemann W, Rassow B (1987) Automatic infrared refractors—a comparative study. Am J Optom Physiol Opt 64:627–638

    Google Scholar 

  25. Wesemann W, Norcia AM, Allen D (1991) Theory of eccentric photorefraction (photoretinoscopy): astigmatic eyes. J Opt Soc Am 8:2038–2047

    Google Scholar 

  26. Wesemann W, Wesemann H (1994) Photorefraction—an objective refraction technique for small children. In: Schulz E (ed) Symposium (to honor Professor Dr. Wolfgang Haase on his 60th birthday) on visual development and “update” in strabismus. Strabismus 2:147–168

    Google Scholar 

  27. Wesemann W, Dick B (2000) Accuracy and accommodation capability of a handheld autorefractor. J Cataract Refract Surg 26:62–70

    Article  Google Scholar 

Download references

Acknowledgements

The authors have no financial interest in any of the products mentioned in the manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Thilo Schimitzek.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Schimitzek, T., Lagrèze, W.A. Accuracy of a new photorefractometer in young and adult patients. Graefe's Arch Clin Exp Ophthalmol 243, 637–645 (2005). https://doi.org/10.1007/s00417-004-1056-y

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00417-004-1056-y

Keywords

Navigation