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Project hyperopic power prediction: accuracy of 13 different concepts for intraocular lens calculation in short eyes
  1. Jascha Wendelstein1,
  2. Peter Hoffmann2,
  3. Nino Hirnschall3,
  4. Isaak Raphael Fischinger1,4,
  5. Siegfried Mariacher1,
  6. Tina Wingert1,
  7. Achim Langenbucher5,
  8. Matthias Bolz1
  1. 1 Department of Ophthalmology and Optometry, Kepler University Hospital, Linz, Oberösterreich, Austria
  2. 2 Department of Ophthalmology, Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
  3. 3 Department of Ophthalmology and Optometry, Hanusch Hospital, Wien, Wien, Austria
  4. 4 Department of Ophthalmology, Augentagesklinik Spreebogen Berlin GbR, Berlin, Germany
  5. 5 Institut für Experimentelle Ophthalmologie, Saarland University, Saarbrucken, Saarland, Germany
  1. Correspondence to Dr Isaak Raphael Fischinger, Ophthalmology, Augentagesklinik Spreebogen Berlin GbR, 4020 Linz, Germany; isaak.fischinger{at}


Purpose To evaluate the accuracy of intraocular lens (IOL) power calculation in a patient cohort with short axial eye length to assess the performance of IOL power calculation schemes in strong hyperopes.

Methodology The study was a single centre, single surgeon retrospective consecutive case series at the Augen- und Laserklinik, Castrop-Rauxel, Germany. Inclusion of patients after uneventful cataract surgery implanting either spherical (SA60AT) or aspheric (ZCB00) IOLs. Inclusion criteria were axial eye length <21.5 mm and/or emmetropising IOL power >28.5 D. Lens constants were optimised on a separate patient cohort considering the full bandwidth of axial eye length. Data of one single eye per patient were randomly included. The outcome measures were: mean absolute prediction error (MAE), median absolute prediction error, mean prediction error with SD and median prediction error and the percentage of eyes with an MAE within 0.25 D, 0.5 D, 0.75 D and 1.0 D.

Results A total of 150 eyes from 150 patients were assessed. Okulix, PEARL-DGS, Kane and Castrop provided a statistically significantly smaller MAE compared with the Hoffer Q and SRK/T formulae.

Conclusion In our patient cohort with short axial eye length, the use of PEARL-DGS, Okulix, Kane or Castrop formulae showed the lowest MAE. The Castrop formula has not been published before, but will be disclosed with a ready-to-use Excel sheet as an addendum to this paper.

  • lens and zonules
  • optics and refraction
  • posterior chamber

Data availability statement

All data relevant to the study are included in the article or uploaded as online supplemental information.

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Data availability statement

All data relevant to the study are included in the article or uploaded as online supplemental information.

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  • Contributors Concept and design of the study: JW, PH, NH, AL and MB. Data acquisition: PH. Data analysis/interpretation: JW, TW, PH, IRF, AL and NH. Drafting the manuscript: JW, IRF, TW and SM. Critical revision of manuscript: PH, NH, AL and MB. Administrative, technical or material support: PH, TW, SM, IRF and JW. Supervision: PH, NH, AL and MB.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.

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