Abstract
Purpose: The GDx is a scanning laser polarimeter that has been developed to allow the quantitative analysis of retinal nerve fibre layer (RNFL) thickness. The purpose of this study was to determine whether differences in the RNFL thickness between normal, ocular hypertensive and glaucomatous eyes could be detected using the GDx.
Methods: RNFL analysis was carried out using the GDx on 33 normal, 145 ocular hypertensive (OHT) and 44 glaucomatous (POAG) eyes. The inclusion criteria for entry into the study did not include the clinical appearance of the RNFL or optic disc, thus eliminating an important source of selection bias. The Kruskal-Wallis one-way analysis of variance was used to determine whether any significant differences existed among the groups in mean total and quadrantic RNFL thickness. When significant differences were found, specific inter-group analysis was carried out using the Mann-Whitney U-test.
Results: Significant differences in RNFL thickness were found for the mean total, superior and inferior quadrant values between normals and OHT eyes as compared with POAG eyes. No significant differences were found for these values between the normal and OHT eyes.
Conclusion: Analysis of RNFL thickness using the GDx was able to detect differences between POAG eyes compared with normal and OHT eyes, although there was considerable overlap between groups. Further assessment of the technique is required to determine whether it may be useful in screening for the presence of early glaucomatous damage.
Similar content being viewed by others
Article PDF
References
Hoyt WF, Newman NM . The earliest defect in glaucoma? Lancet 1972;1:692–3.
Sommer A, Katz J, Quigley HA, Miller NR, Robin AL, Richter RC, et al. Clinically detectable nerve fiber atrophy precedes the onset of glaucomatous field loss. Arch Ophthalmol 1991;109:77–83.
Airaksinen pJ, Drance SM, Douglas GR, Mawson DK, Nieminen H . Diffuse and localised nerve fiber loss in glaucoma. Am J Ophthalmol 1984;98:566–71.
Quigley HA, Katz J, Derick RJ, Gilbert D, Sommer A . An evaluation of optic disc and nerve fiber layer examinations in monitoring progression of early glaucoma damage. Ophthalmology 1992;99:19–28.
Weinreb RN, Shakiba S, Zangwill L . Scanning laser polarimetry to measure the nerve fiber layer of normal and glaucomatous eyes. Am J Ophthalmol 1995;119:627–36.
Tjon-Fo-Sang MJ, de Vries J, Lemij HG . Measurement by nerve fiber analyzer of retinal nerve fiber layer thickness in normal subjects and patients with ocular hypertension. Am J Ophthalmol 1996;122:220–7.
Hollo G, Suveges I, Nagymihaly A, Vargha P . Scanning laser polarimetry of the retinal nerve fibre layer in primary open angle glaucoma and capsular glaucoma. Br J Ophthalmol 1997;81:857–61.
Garway-Heath DF, Hitchings RA . Quantitative evaluation of the optic nerve head in early glaucoma. Br J Ophthalmol 1998;82:352–61.
AGIS Investigators. Advanced Glaucoma Intervention Study. Ophthalmology 1994;101:1445–55.
Anton A . Emdadi A . Weinreb R. Nerve fiber layer measurements with scanning laser polarimetry in ocular hypertension. Arch Ophthalmol 1997;115:331–4.
Xu L, Chen PP, Chen YY, Takahashi Y, Wang L, Mills RP . Quantitative nerve fibre layer measurement using scanning laser polarimetry and modulation parameters in the detection of glaucoma. J Glaucoma 1998;7:270–7.
Weinreb R, Berry CC, Bathija R, Sample PA . Detection of glaucoma with scanning laser polarimetry. Arch Ophthalmol 1998;116:1583–9.
Lee Mok KH . Retinal nerve fibre layer measurement by nerve fibre analyser in normal subjects and patients with glaucoma. Ophthalmology 1999;106:1006–8.
Quigley HA, Addicks EM, Green WR . Optic nerve damage in human glaucoma. III. Quantitative correlation of nerve fibre loss and visual field defect in glaucoma, ischaemic neuropathy, papilloedema, and toxic neuropathy. Arch Ophthalmol 1982;100:135–46.
Quigley HA, Kerrigan-Baumrind LA, Pease ME, Kerrigan DF, Mitchell RS . The number of retinal ganglion cells in glaucoma eyes compared to threshold visual field data in the same eyes. Invest Ophthalmol Vis Sci 1999;40:S582.
Tjon-Fo-Sang ML, Lemij H . The sensitivity and specificity of nerve fiber layer measurements in glaucoma as determined with scanning laser polarimetry. Am J Ophthalmol 1997;123:62–9.
Chi Q, Tomita G, Inazumi K, Hayakawa T, Ido T, Kitazawa Y . Evaluation of the effect of aging on the retinal nerve fibre layer thickness using scanning laser polarimetry. J Glaucoma 1995;4:406–13.
Poinoosawmy D, Fontana L, Wu JX, Fitzke FW, Hitchings RA . Variation of nerve fibre layer thickness measurements with age and ethnicity by scanning laser polarimetry. Br J Ophthalmol 1997;81:1–5.
Niessen AG, van den Berg TJ, Langerhorst CT, Greve EL . Retinal nerve fiber layer assessment by scanning laser polarimetry and standardized photography. Am J Ophthalmol 1996;121:484–93.
Waldocks A, Potts MJ, Sparrow JM, Karwatowski WS . Clinical evaluation of scanning laser polarimetry. I. Intra-operator reproducibility and design of a blood vessel removal alogorithm. Br J Ophthalmol 1998;82:252–9.
Poinoosawmy D, Bunce C, Kamal D, Hitchings R . Comparison of one-two year change in RNFL thickness in normal tension glaucoma patients with normal subjects. Invest Ophthalmol Vis Sci 1999;40:S65.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kamal, D., Bunce, C. & Hitchings, R. Use of the GDx to detect differences in retinal nerve fibre layer thickness between normal, ocular hypertensive and early glaucomatous eyes. Eye 14, 367–370 (2000). https://doi.org/10.1038/eye.2000.90
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1038/eye.2000.90
Keywords
This article is cited by
-
A comparison of HRT II and GDx imaging for glaucoma detection in a primary care eye clinic setting
Eye (2007)
-
Influence of optic disc size on parameters of retinal nerve fiber analysis with laser scanning polarimetry
Graefe's Archive for Clinical and Experimental Ophthalmology (2006)
-
Histological measurement of retinal nerve fibre layer thickness
Eye (2005)
-
Effect of cataract extraction and intraocular lens implantation on nerve fibre layer thickness measurements by scanning laser polarimeter (GDx) in glaucoma patients
Eye (2004)
-
Scanning laser polarimetry in patients with acute angle-closure glaucoma
Eye (2004)