Discrimination between Normal and Early Stage of Glaucomatous Eyes Using the Stratus Optical Coherence Tomography

Yoo-Mi Song; Ki Bang Uhm

doi:10.3341/jkos.2007.48.12.1675

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Song and Uhm: Discrimination between Normal and Early Stage of Glaucomatous Eyes Using the Stratus Optical Coherence Tomography

Original Article

J Korean Ophthalmol Soc 2007;48(12):1675-1685.

Published online: 30 August 2007

DOI: https://doi.org/10.3341/jkos.2007.48.12.1675

Discrimination between Normal and Early Stage of Glaucomatous Eyes Using the Stratus Optical Coherence Tomography

Yoo-Mi Song, M.D., Ki Bang Uhm, M.D.

Department of Ophthalmology, Hanyang University College of Medicine, Seoul, Korea

Address reprint requests to Ki Bang Uhm, M.D., Department of Ophthalmology, College of Medicine, Hanyang University, #17 Haengdang-dong, Sungdong-gu, Seoul 133-792, Korea, Tel: 82-2-2290-8570, Fax: 82-2-2290-8570, E-mail: KBUhm@hanyang.ac.kr

Received 31 January 2007 Accepted 21 August 2007

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Purpose

To evaluate the diagnostic ability of Stratus optical coherence tomography (OCT) parameters to distinguish normal eyes from those with early glaucomatous visual field defects.

Methods

One eye each of 52 normal-tension glaucoma patients with early visual field defects (mean deviation, −3.98±1.30dB; range, −0.01 to −5.86dB) and 88 age-matched normal subjects were enrolled. The Peripapillary retinal nerve fiber layer (RNFL) and optic nerve head regions were scanned using the Stratus OCT. Areas under the receiver operating characteristic curve (AROC) and the sensitivity and specificity for various OCT parameters were used to assess the performance of OCT.

Results

The AROC for the C/D area ratio was 0.865. Other high AROC values included the vertical C/D ratio (0.848), the average RNFL thickness (0.813), and the RNFL thickness in the inferior quadrant (0.791). A stepwise discriminant analysis found that a combination of the C/D area ratio and RNFL thickness in the inferior quadrant could correctly identify 86.4% of the normals and 80.8% of the glaucoma patients (AROC=0.893).

Conclusions

In our sample of patients with early visual field defects, Stratus OCT parameters showed moderate discriminating abilities. Combining the C/D area ratio and RNFL thickness in the inferior quadrant by discriminant analysis improved the diagnostic ability to detect glaucoma.

Keywords: Discriminant analysis, Glaucoma, Optical coherence tomography, Optic nerve, Retinal nerve fiber layer

References

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; 100:135–46.

2. Sommer A, Katz J, Quigley HA, et al. Clinically detectable nerve fiber atrophy precedes the onset of glaucomatous field loss. Arch Ophthalmol. 1991; 109:77–83.

3. Quigley HA, Katz J, Derick RJ, et al. An evaluation of optic disc and nerve fiber layer examinations in monitoring progression of early glaucoma damage. Ophthalmology. 1992; 99:19–28.

4. Uhm KB, Hong C, Kim JH, Baek CE. Sensitivity, specificity, and predictive value of optic disc parameters in primary open-angle glaucoma. J Korean Ophthalmol Soc. 1997; 38:1819–26.

5. Jonas JB, Gusek GC, Naumann GO. Optic disc, cup and neuroretinal rim size, configuration and correlations in normal eyes. Invest Ophthalmol Vis Sci. 1995; 29:1151–8.

6. Chi T, Ritch R, Stickler D, et al. Racial differences in optic nerve head parameters. Arch Ophthalmol. 1989; 107:836–9.

7. Poinoosawmy D, Fontana L, Wu JX, et al. Variation of nerve fiber layer thickness measurements with age and ethnicity by scanning laser polarimetry. Br J Ophthalmol. 1997; 81:350–4.

8. Paunescu LA, Schuman JS, Price LL, et al. Reproducibility of nerve fiber thickness, macular thickness, and optic nerve head measurements using Stratus OCT. Invest Ophthalmol Vis Sci. 2004; 45:1716–24.

9. Garway-Heath DF, Hitchings RA. Sources of bias in studies of optic disc and retinal nerve fiber layer morphology. Br J Ophthalmol. 1998; 82:986.

10. Brusini P, Salvetat ML, Zeppieri M, et al. Comparison between GDx VCC scanning laser polarimetry and Stratus OCT optical coherence tomography in the diagnosis of chronic glaucoma. Acta Ophthalmol Scand. 2006; 84:650–5.

11. Bourne RR, Medeiros FA, Bowd C, et al. Comparability of retinal nerve fiber layer thickness measurements of optical coherence tomography instruments. Invest Ophthalmol Vis Sci. 2005; 46:1280–5.

12. Pieroth L, Schuman JS, Hertzmark E, et al. Evaluation of focal defects of the nerve fiber layer using optical coherence tomography. Ophthalmology. 1999; 106:570–9.

13. Chen HY, Huang ML. Discrimination between normal and glaucomatous eyes using Stratus optical coherence tomography in Taiwan Chinese subjects. Graefes Arch Clin Exp Ophthalmol. 2005; 243:894–902.

14. Medeiros FA, Zangwill LM, Bowd C, et al. Evaluation of retinal nerve fiber layer, optic nerve head, and macular thickness measurements for glaucoma detection using optical coherence tomography. Am J Ophthalmol. 2005; 139:44–55.

15. Wollstein G, Ishikawa H, Wang J, et al. Comparison of three optical coherence tomography scanning areas for detection of glaucomatous damage. Am J Ophthalmol. 2005; 139:39–43.

16. Manassakorn A, Nouri-Mahdavi K, Caprioli J. Comparison of retinal nerve fiber layer thickness and optic disk algorithms with optical coherence tomography to detect glaucoma. Am J Ophthalmol. 2006; 141:105–15.

17. Bowd C, Zangwill LM, Berry CC, et al. Detecting early glaucoma by assessment of retinal nerve fiber layer thickness and visual function. Invest Ophthalmol Vis Sci. 2001; 42:1993–2003.

18. Zangwill LM, Bowd C, Berry CC, et al. Discriminating between normal and glaucomatous eyes using the Heidelberg retina tomograph, GDx nerve fiber analyzer, and optical coherence tomograph. Arch Ophthalmol. 2001; 119:985–93.

19. Kamal DS, Garway-Heath DF, Hitchings RA, et al. Use of sequential Heidelberg retina tomograph images to identify changes at the optic disc in ocular hypertensive patients at risk of developing glaucoma. Br J Ophthalmol. 2000; 84:993–8.

20. Parisi V, Manni G, Centofanti M, et al. Correlation between optical coherence tomography, pattern electroretinogram, and visual evoked potentials in open-angle glaucoma patients. Ophthalmology. 2001; 108:905–12.

21. Kang KD, Park CK. Comparison of diagnostic precision between preprogramed indicator and newly calculated indicator in optical coherence tomography. J Korean Ophthalmol Soc. 2006; 47:243–52.

22. Leung CK, Chan WM, Hui YL, et al. Analysis of retinal nerve fiber layer and optic nerve head in glaucoma with different reference plane offsets, using optical coherence tomography. Invest Ophthalmol Vis Sci. 2005; 46:891–9.

23. Iliev ME, Meyenberg A, Garweg JG. Morphometric assessment of normal, suspect and glaucomatous optic discs with Stratus OCT and HRT II. Eye. 2006; 20:1288–99.

24. Schuman JS, Wollstein G, Farra T, et al. Comparison of optic nerve head measurements obtained by optical coherence tomography and confocal scanning laser ophthalmoscopy. Am J Ophthalmol. 2003; 135:504–12.

25. Jonas JB, Schmidt AM, Muller-Bergh JA, et al. Human optic nerve fiber count and optic disc size. Invest Ophthalmol Vis Sci. 1992; 33:2012–8.

26. Savini G, Zanini M, Carelli V, et al. Correlation between retinal nerve fiber layer thickness and optic nerve head size:an optical coherence tomography study. Br J Ophthalmol. 2005; 89:489–92.

27. Bowd C, Zangwill LM, Blumenthal EZ, et al. Imaging of the optic disc and retinal nerve fiber layer: the effects of age, optic disc area, refractive error, and gender. J Opt Soc Am A Opt Image Sci Vis. 2002; 19:197–207.

Figure 1.

Areas under the receiver operating characteristic curves (AROC) of the linear discriminant function (LDF), of the best parameters from the Stratus OCT optic nerve head (cup/disc area ratio and vertical cup/disc ratio) and retinal nerve fiber layer (average thickness and inferior quadrant thickness).

Table 1.

Characteristics of the study groups

	Normal eyes (n=88)	Early glaucomatous eyes (n=52)	P value
Age (years)	60.1±10.3	59.2±10.6	0.63
Gender (male:female)	38:50	23:29	0.90
Refractive error (diopter)	0.16±1.32	-0.37±2.10	0.08
MD (dB)	-1.87±1.18	-3.98±1.30	<0.001
CPSD (dB)	1.68±0.37	3.74±1.91	<0.001

Values are number or means±standard deviation.

MD=mean deviation, CPSD=corrected pattern standard deviation.

Table 2.

Comparison of Stratus OCT parameters between the two groups

	Normal eyes (n=88)	Early glaucomatous eyes (n=52)	P value
Optic disc parameters
Disc area (mm²)	2.57±0.56	3.05±0.70	<0.001
VIRA (mm³)	0.30±0.20	0.14±0.11	<0.001
HIRW (mm²)	1.55±0.25	1.30±0.30	<0.001
Cup area (mm²)	1.04±0.48	1.93±0.85	<0.001
Rim area (mm²)	1.53±0.42	1.07±0.44	<0.001
C/D area ratio	0.40±0.13	0.63±0.17	<0.001
Horizontal C/D ratio	0.67±0.14	0.82±0.14	<0.001
Vertical C/D ratio	0.57±0.11	0.74±0.13	<0.001
RNFL thickness parameters (μm)
Average	103.8±10.9	85.8±19.8	<0.001
Superior quadrant	127.3±16.0	104.4±27.3	<0.001
Temporal quadrant	72.6± 15.9	63.5±17.9	0.002
Inferior quadrant	133.8±17.9	106.8±29.5	<0.001
Nasal quadrant	81.7±17.1	68.5±23.3	<0.001
O'clock hour segment
12 (superior)	132.6±21.6	107.9±32.4	<0.001
11	132.4±23.9	107.5±33.5	<0.001
10	88.0±20.0	7 5.1±23.2	0.001
9 (temporal)	57.6±12.6	53.0± 15.5	0.055
8	72.8±20.6	64.0±22.0	0.018
7	137.2±24.1	112.3±38.5	<0.001
6 (inferior)	148.3±27.2	115.2±34.6	<0.001
5	115.9±22.1	92.7±29.2	<0.001
4	81.5±19.5	70.9±25.7	0.007
3 (nasal)	67.1±16.5	57.2±20.4	0.002
2	96.1±23.4	77.9±28.5	<0.001
1	117.1±19.6	97.5±28.5	<0.001

Values are means±standard deviation.

VIRA=vertical integrated rim area (an estimation of the total volume of the RNFL tissue in the rim), HIRW=horizontal integrated rim width (an estimation of the total neuroretinal rim area). RNFL=retinal nerve fiber layer.

Table 3.

Areas under the receiver operator characteristic curve (AROC), sensitivity, specificity, best cut-off point, and accuracy for Stratus OCT parameters and linear discriminant function

	AROC (SE)	Best sensitivity/specificity (%)	Bestcut-off point	Sensitivity (%) at Specificity of 80%	Accuracy (%)
Optic disc parameters
VIRA (mm³)	0.824±0.040	80.7/75.0	0.155	71.6	66.4
HIRW (mm²)	0.738±0.043	67.0/63.5	1.427	53.4	65.0
Cup area (mm²)	0.823±0.040	76.9/73.9	1.258	69.2	76.4
Rim area (mm²)	0.786±0.042	76.1/75.0	1.253	60.2	71.4
C/D area ratio	0.865±0.037	82.7/78.4	0.517	82.7	80.0
Horizontal C/D ratio	0.819±0.041	80.8/65.9	0.748	71.2	71.4
Vertical C/D ratio	0.848±0.037	78.8/77.3	0.661	75.0	77.9
RNFL thickness parameters (μm)
Average	0.813±0.039	71.6/76.9	97.86	65.9	72.1
Superior quadrant	0.781±0.043	69.3/69.2	117.5	48.9	73.6
Temporal quadrant	0.623±0.050	55.7/55.8	67.50	29.5	54.3
Inferior quadrant	0.791±0.041	70.5/75.0	124.5	51.1	73.6
Nasal quadrant	0.673±0.049	59.1/61.5	76.50	30.7	59.3
O'clock hour segment
12 (superior)	0.742±0.045	69.3/65.4	122.5	50.0	67.1
11	0.725±0.045	65.9/65.4	124.5	50.0	65.0
10	0.639±0.049	59.1/50.0	80.50	33.0	57.1
9 (temporal)	0.574±0.053	56.8/55.8	54.50	17.0	54.3
8	0.598±0.051	55.7/55.8	67.00	26.1	52.9
7	0.677±0.048	59.1/63.5	131.5	42.0	62.9
6 (inferior)	0.779±0.041	70.5/71.2	133.5	60.2	70.0
5	0.737±0.043	65.9/63.5	106.5	53.4	62.1
4	0.608±0.052	54.5/53.8	76.50	27.3	54.3
3 (nasal)	0.645±0.050	60.2/59.6	60.50	34.1	56.4
2	0.679±0.047	56.8/57.7	87.50	43.2	58.6
1	0.715±0.046	65.9/65.4	109.5	50.0	65.7
Linear discriminant function	0.405-0.023×inferior quadrant RNFL thickness+5.096×cup/disc area ratio
	0.893±0.032	80.8/86.4	0.224	82.7	84.3

SE=standard error, VIRA=vertical integrated rim area, HIRW=horizontal integrated rim width, RNFL=retinal nerve fiber layer.

Table 4.

Correlation between Stratus OCT parameters and mean deviation (MD) or corrected pattern standard deviation (CPSD) of the Humphrey full-threshold 30-2 program

	MD		CPSD
	R	P value	R	P value
Optic disc parameters
Disc area (mm²)	-0.111	0.365	0.199	0.102
VIRA (mm³)	0.316	0.008	-0.238	0.049
HIRW (mm²)	0.388	0.001	-0.239	0.047
Cup area (mm²)	-0.286	0.017	0.260	0.031
Rim area (mm²)	0.395	0.001	-0.148	0.224
C/D area ratio	-0.384	0.001	0.221	0.069
Horizontal C/D ratio	-0.280	0.020	0.115	0.347
Vertical C/D ratio	-0.368	0.002	0.294	0.014
RNFL thickness parameters (μm)
Average	0.464	<0.001	-0.312	0.009
Superior quadrant	0.422	<0.001	-0.301	0.012
Temporal quadrant	0.214	0.078	-0.177	0.146
Inferior quadrant	0.454	<0.001	-0.431	<0.001
Nasal quadrant	0.405	0.001	-0.029	0.814
O'clock hour segment
12 (superior)	0.441	<0.001	-0.321	0.007
11	0.181	0.136	-0.176	0.148
10	0.142	0.246	-1.134	0.271
9 (temporal)	0.101	0.411	-0.050	0.683
8	0.239	0.048	-0.261	0.030
7	0.361	0.002	-0.499	<0.001
6 (inferior)	0.412	<0.001	-0.405	0.001
5	0.426	<0.001	-0.197	0.117
4	0.362	0.002	-0.030	0.805
3 (nasal)	0.423	<0.001	0.052	0.671
2	0.367	0.002	-0.087	0.478
1	0.461	<0.001	-0.315	0.008
Discriminant score	-0.479	<0.001	0.360	0.002

^* VIRA=vertical integrated rim area, HIRW=horizontal integrated rim width, RNFL=retinal nerve fiber layer.

Table 5.

The best parameters and linear discriminant function of stratus OCT for the present study and published studies

References	MD (dB)	The best parameters		Linear discriminant function
	Glaucoma severity	ONH (AROC)	RNFLT (AROC)	(AROC)
Present study	-3.98	C/D area ratio (0.87)	Average (0.81)	C/D area ratio +
	early	Vertical C/D ratio (0.85)	Inferior quadrant (0.79)	Inferior quadrant RNFLT (0.89)
1. Brusini et al¹⁰	-3.70	C/D area ratio (0.88)	Average (0.84)	NA
	early to
	moderate
2. Chen et al¹³	-2.80	Vertical C/D ratio (0.73)	Average (0.79)	Average RNFLT +
	early		C/D area ratio (0.71)	10+11+12 o'clock thickness+Cup
				area+VIRA (0.88)
3. Medeiros et al¹⁴	-4.96	C/D area ratio (0.88)	Inferior quadrant (0.91)	C/D area ratio+Average RNFLT+
	early to	Vertical C/D ratio (0.88)	Average (0.91)	7+11+9 o'clock thickness (0.97)
	severe	HIRW (0.88)	Inferior maximum (0.90)
4. Wollstein et al¹⁵	-5.85	Rim area (0.97)	Average (0.94)	NA
	early to	HIRW (0.96)
	severe	VIRA (0.95)
5. Manassakorn et al¹⁶	-5.30	Vertical C/D ratio (0.90)	7 o'clock thickness (0.93)	NA
	early to		Inferior quadrant (0.92)
	severe

^* MD=mean deviation, ONH=optic nerve head, RNFL=retinal nerve fiber layer thickness, AROC=areas under the receiver operator characteristic curve, NA=not applicable, VIRA=vertical integrated rim area, HIRW=horizontal integrated rim width.

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