Advertisement

Clinical Utility of Computerized Optic Nerve Analysis

  • Neil T. Choplin
Chapter

Abstract

This chapter emphasizes the point that glaucoma is a disease of retinal nerve fibers and their ganglion cells. The diagnosis and management of glaucoma requires the ability to detect the loss of retinal nerve fibers (i.e., determining if an individual has less nerve fibers than he/she is supposed to have based upon the population from which he/she comes) and to determine if the loss of retinal nerve fibers occurs at a rate greater than what is expected from normal aging. The “traditional” method for doing this has been through direct ophthalmoscopy and the determination of the cup-to-disc ratio, with the assumption that “cupping” represents the loss of nerve fibers from the neuroretinal rim. The problem with the traditional method is that it has no way of accounting for the large structural variability of human optic nerve heads. A cup-to-disc ratio of 0.6, for example, may be quite normal in an axial myope, but may be quite pathological if it was 0.3 ten years before the patient was ever seen by the eye care provider. Likewise, it may be quite normal if the disc is large, and abnormal if the disc is small. Plus, the determination of cup-to-disc ratio only provides an (subjective) indirect measure of the retinal nerve fiber layer, the tissue of interest in glaucoma. Small changes in cup-to-disc ratio may be very difficult to detect by ophthalmoscopy, and progression may go unnoticed for years. Hence, better methods are required and, as outlined in this chapter, have been developed.

Keywords

Optical Coherence Tomography Retinal Nerve Fiber Layer Optic Nerve Head Heidelberg Retinal Tomograph Computerize Scanning Imaging 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. 1.
    Quigley HA, Addicks EM, Green WR. Optic nerve damage in human glaucoma III. Quantitative correlation of nerve fiber loss and visual field defect in glaucoma, ischemic neuropathy, papilledema, and toxic neuropathy. Arch Ophthalmol. 1982;100:135–146.PubMedGoogle Scholar
  2. 2.
    Weinreb RN, Dreher AW, Coleman A, et al. Histopathologic validation of Fourier-ellipsometry measurements of retinal nerve fiber layer thickness. Arch Ophthalmol. 1990;108:557–560.PubMedGoogle Scholar
  3. 3.
    Fortune, B, Wang, G, Cull, Cioffi GA. Intravitreal colchicine causes decreased retinal nerve fiber layer thickness measured by scanning laser polarimetry but not by optical coherence tomography in non-human primates. Inv Vis Sci. 2007;(48), Abstract no. 2877.Google Scholar
  4. 4.
    Yamada N, Tomita G, Yamamoto T, Kitazawa Y. Changes in the nerve fiber layer thickness following a reduction of intraocular pressure after trabeculectomy. J Glaucoma. 2000;9(5):371–375.Google Scholar
  5. 5.
    Aydin A, Wollstein G, Price LL, Fujimoto JG, Schuman JS. Optical coherence tomography assessment of retinal nerve fiber layer thickness changes after glaucoma surgery. Ophthalmology. 2003;110(8):1506–1511.CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Neil T. Choplin
    • 1
  1. 1.Eye Care of San DiegoSan DiegoUSA

Personalised recommendations