Korean J Ophthalmol.  2006 Mar;20(1):26-32. 10.3341/kjo.2006.20.1.26.

Comparison of Retinal Nerve Fiber Layer Measurements between NTG and HTG using GDx-VCC

• Jung JY
• Kim JH
• Kook MS

• KMID: 1099069
• DOI: http://doi.org/10.3341/kjo.2006.20.1.26

Abstract

PURPOSE: To compare quantitative polarimetric measurements in eyes with NTG and HTG using GDx-VCC. Both groups were matched by age and glaucoma stage based on the Humphrey visual field test. METHODS: We retrospectively reviewed the records of 146 patients who underwent Humphrey field analysis (HFA) and GDx-VCC. We compared outcomes of retinal nerve fiber layer (RNFL) parameters among the three groups by ANOVA and between each pair of groups using the Tukey-Kramer Post-Hoc test. We also evaluated the sensitivity and specificity of GDx-VCC in detecting glaucoma in each group. RESULTS: The mean age and HFA mean deviation (MD) were 55.6+/-9.5 years and -0.8+/-1.5 dB in 47 control patients, 59.4+/-9.0 years and -5.77+/-4.38 dB in 49 NTG patients, and 59.4+/-11.7 years and -8.09+/-6.77 dB in 51 HTG patients, respectively. All thickness parameters were lower in HTG patients compared to NTG patients, but there were no significant differences in ratio parameters between age-matched early HTG and NTG patients. The sensitivity of GDx-VCC was significantly higher in both early and total HTG patients compared to the respective groups of NTG patients. CONCLUSIONS: Compared to eyes with NTG, eyes with HTG showed reduced RNFL thickness and ratio parameters when patients were age and visual field matched. GDx-VCC appeared to be more sensitive in detecting RNFL damage in HTG patients.

Keyword

Normal-tension glaucoma (NTG); High-tension glaucoma (HTG); scanning laser polarimetry with variable corneal compensation (GDx-VCC)

MeSH Terms

Visual Fields
Severity of Illness Index
Retrospective Studies
Retinal Ganglion Cells/*pathology
Perimetry/*methods
Nerve Fibers/*pathology
Middle Aged
Lasers/*diagnostic use
Intraocular Pressure/*physiology
Humans
Glaucoma, Open-Angle/*pathology/physiopathology
Follow-Up Studies
Aged

Figure

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  Fig. 1 Comparison of thickness parameters in all NTG and HTG eyes. TSNIT AVE: temporal superior nasal inferior temporal average, SUPAVE: superior average, INFAVE: inferior average, SUPMAX: superior maximum, INFMAX: inferior maximum, ELLAVE: ellipse average, *P<0.05 by Post Hoc Tukey-Kramer test.

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  Fig. 2 Ratio and modulation parameters in all NTG and HTG eyes. INESYMM: intereye symmetry, SYMMETRY: symmetry, SUPRATIO: superior ratio, INFRATIO: inferior ratio, SUPNAS: superior/nasal ratio, MAXMOD: maximal modulation, ELLIMOD: ellipse modulation, *P<0.05 by Post Hoc Tukey-Kramer test.

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  Fig. 3 Comparison of thickness parameters in early stage NTG and HTG eyes (Humphrey visual field mean deviation >-6dB) TSNIT AVE: temporal superior nasal inferior temporal average, SUPAVE: superior average, INFAVE: inferior average, SUPMAX: superior maximum, INFMAX: inferior maximum, ELLAVE: ellipse average. *P<0.05 by Post Hoc Tukey-Kramer test.

• 

  Fig. 4 Comparison of ratio and modulation parameters in early stage NTG and HTG eyes (Humphrey visual field mean deviation >-6dB) INESYMM: intereye symmetry, SYMMETRY: symmetry, SUPRATIO: superior ratio, INFRATIO: inferior ratio, SUPNAS: superior/nasal ratio, MAXMOD: maximal modulation, ELLIMOD: ellipse modulation. *P<0.05 by Post Hoc Tukey-Kramer test.

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