Abstract
One of the main clinical parameters expressing the health of a cornea is the cell density of its endothelium. This information is particularly important in an eye bank environment, where donor corneas are screened to assess their suitability as a human graft. Endothelium cell density is conventionally estimated by a long, tedious and error-prone manual counting procedure, performed by cornea experts on specimen images observed through an optical microscope. An alternative solution is proposed: a computer program that provides automatic estimation of cell density in donor corneas by analysing the spatial frequencies contained in the image. A circular band in the 2D discrete Fourier transform of the image is shown to contain the relevant information about the cell density. A system for extracting from this spatial frequency information an estimate of the cell density has been developed. A clinical evaluation of the proposed technique was performed on 18 corneas, where the densities provided by the proposed technique were compared with those manually obtained by two experts. The results showed an average percentage difference of 3% (maximum 19%), a value well within the measured inter-expert range of variability. The proposed automatic procedure confirmed its ability to estimate correctly corneal endothelium cell density.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Armitage, W., Dick, A., andBourne, W. (2003): ‘Predicting endothelial cell loss and long-term corneal graft survival’,Invest. Ophthalmol. Vis. Sci.,44, pp. 3326–3321
Barisani-Asenbauer, T., Baumgartner, I., Grabner, G., andStur, M. (1993): ‘Automated digital image analysis of organ culture preserved donor corneas’,Ophthal. Res.,25, pp. 94–99
Benetz, B., Diaconu, E., Bowlin, S., Oak, S., Laing, R., andLass, J. H. (1999): ‘Comparison of corneal endothelial image analysis by Konan SP8000 Non-Contact and Bio-Optics Bambi systems’,Cornea,18, pp. 67–72
Corkidi, G., Marquez, J., Usisima, R., Toledo, R., Valdez, J., andGraue, E., (1993): ‘Automatedin vivo and online morphometry of human endothelium’,Med. Biol. Eng. Comput.,31, pp. 421–426
Dhawan, A. P. (2003): ‘Medical image analysis’ (Wiley-Interscience, 2003)
Fitzke, F., Masters, B., Buckley, R., andSpeedwell, L. (1997): ‘Fourier transform analysis of human corneal endothelial specular photomicrographs’,Exp. Eye Res.,65, pp. 205–214
Foracchia, M., andRuggeri, A., (2000): ‘Cell contour detection in corneal endotheliumin-vivo microscopy’, inFullerton, G. (Ed.): Proc. 22nd Annual IEEE-EMBS Conf. IEEE, New York, pp. 1033–1035
Gain, P., Thuret, G., Gavet, Y., Turc, P., Acquart, S., Desbois, I., Le Petit, J., andCampos, L. (2002): ‘Automated tri-image analyser of stored corneal endothelium’,Br. J. Ophthalmol.,86, pp. 801–808
Hartmann, C., andKöditz, W. (1984): ‘Automated morphometric endothelial analysis combined with video specular microscopy’,Cornea,3, pp. 155–167
Hasegawa, A., Itoh, K., andIchioka, Y., (1992): ‘Detection of cell membranes in human corneal endothelial micrograms using mathematical morphology’,Jpn. J. Appl. Phys.,31, pp. 798–804
Hasegawa, A., Itoh, K., andIchioka, Y. (1996): ‘Generalization of shift invariant neural networks: image processing of corneal endothelium’,Neural Networks,9, pp. 345–356
Hirst, L., Sterner, R., andGrant, D. (1984): ‘Automated analysis of wide-field specular photomicrographs’,Cornea,3, pp. 83–87
Jaroszewski, J., Rieger, R., Rieck, P., Hartmann, C., Grisan, E., andRuggeri, A. (2003): ‘Computerized endothelial cell density calculation in the cornea bank’,Graefes. Arch. Clin. Exp. Ophthalmol.,241, p. DO.07.06
Lester, J., MacFarland, J., Bursell, S., Laing, R., andBrenner, J. (1981): ‘Automated morphometric analysis of corneal endothelial cells’,Invest. Ophthalmol. Vis. Sci.,20, pp. 407–410
Masters, B. (1988): ‘Characterisation of corneal specular endothelial photomicrographs by their Fourier transforms’, inJuday, R. (Ed.): ‘Digital and optical shape representation and pattern recognition’. Proc. SPIE 938, pp. 246–252
Nishi, O., andHanasaki, K. (1988): ‘Automated morphometry of corneal endothelial cell: use of video camera and video recorder’,Br. J. Ophthalmol.,72, pp. 68–73
Reinhard, T., Spelsberg, H., Holzwarth, D., Dahmen, N., Godehardt, E., andSundmacher, R. (1999): ‘Wissensbasierte bildanalyse des endothels von hornhauttransplantaten’,Klin. Monatsbl. Augenheilkd.,214, pp. 407–411
Siertsema, J., Landesz, M., Van den Brom H., andVan Rij, G. (1993): ‘Automated video image morphometry of corneal endothelium’,Doc. Ophthalmol.,85, pp. 35–44
Thuret, G., Acquart, S., Manissolle, C., Delbosc, B., Borderie, V., Maugery, J., Garraud, O., andGain, P. (2004): ‘Urgent need for normalization of corneal graft quality controls on French eye banks’, Proc. 16th EEBA Conference. European Eye Bank Association, Barcelona, p. 25
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Foracchia, M., Ruggeri, A. Automatic estimation of endothelium cell density in donor corneas by means of Fourier analysis. Med. Biol. Eng. Comput. 42, 725–731 (2004). https://doi.org/10.1007/BF02347557
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02347557