Retinal Nerve Fiber Layer Volume Measurements in Normal Children Using Spectral Domain Optical Coherence Tomography

Dong Eik Lee; Joong Won Shin; Han Woong Lim; Yong Un Shin; Min Ho Kang; Hee Yoon Cho; Min Cheol Seong

doi:10.3341/jkos.2016.57.5.800

Journal List > J Korean Ophthalmol Soc > v.57(5) > 1010591

Go to TopGo to Top Go to BottomGo to Bottom

TOOLS

Lee, Shin, Lim, Shin, Kang, Cho, and Seong: Retinal Nerve Fiber Layer Volume Measurements in Normal Children Using Spectral Domain Optical Coherence Tomography

Original Article

J Korean Ophthalmol Soc 2016;57(5):800-807.

Published online: 7 September 2016

DOI: https://doi.org/10.3341/jkos.2016.57.5.800

Retinal Nerve Fiber Layer Volume Measurements in Normal Children Using Spectral Domain Optical Coherence Tomography

Dong Eik Lee, MD, Joong Won Shin, MD, Han Woong Lim, MD, PhD, Yong Un Shin, MD, PhD, Min Ho Kang, MD, PhD, Hee Yoon Cho, MD, PhD, Min Cheol Seong, MD, PhD

Department of Ophthalmology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea

Address reprint requests to Min Cheol Seong, MD, PhD Department of Ophthalmology, Hanyang University Guri Hospital, #153 Gyeongchun-ro, Guri 11923, Korea Tel: 82-31-560-2354, Fax: 82-31-564-9479 E-mail: goddns76@hanmail.net

Received 21 January 201611 February 2016 Accepted 8 April 2016

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 perm its unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Purpose

To measure retinal nerve fiber layer (RNFL) volume in normal children using spectral domain optical coherence tomography (SD-OCT).

Methods

This study included 79 eyes of 54 normal children between 4 and 15 years of age evaluated from February 2012 to November 2012. All participants underwent ocular examination and 3D-disc scanning using SD-OCT. RNFL volume was calculated between 2.5 and 5 mm diameter circles using the length, width, and height of each pixel derived from the RNFL thickness map with Matlab software. The relationship between RNFL volume and thickness was analyzed.

Results

The RNFL volumes of the mean total, superior, nasal, inferior, and temporal areas were 1.48 ± 0.09 mm³, 0.45 ± 0.04 mm³, 0.29 ± 0.04 mm3, 0.46 ± 0.03 mm3, and 0.29 ± 0.04 mm3, respectively. Comparing RNFL volume and conventional circumpapillary RNFL thickness measured using built-in software, a strong correlation between mean total, superior, and inferior areas (R = 0.980, 0.953 and 0.932, respectively) and a moderate correlation between the nasal and temporal areas were observed (R = 0.545 and 0.514, respectively). The negative correlations between RNFL thickness and RNFL volumes of the mean total, superior, nasal, inferior, and temporal areas and age were not significant (p > 0.05).

Conclusions

This study reports RNFL volume measured from RNFL thickness map analysis in normal children. These data regarding RNFL volume of normal children may provide useful information for diagnosis and monitoring of pediatric glaucoma.

Keywords: Normal children, Retinal nerve fiber layer, Spectral domain optical coherence tomography, Volume

References

1. Tuulonen A. Lehtola J. Alraksinen PJ. Nerve fiber layer defects with normal visual fields. Do normal optic disc and normal visual field indicate absence of glaucomatous abnormality? Ophthalmology. 1993; 100:587–97. discussion. 597–8.

2. Airaksinen PJ. Alanko HI. Effect of retinal nerve fibre loss on the optic nerve head configuration in early glaucoma. Graefes Arch Clin Exp Ophthalmol. 1983; 220:193–6.

3. Rao A. Sahoo B. Kumar M, et al. Retinal nerve fiber layer thickness in children< 18 years by spectral-domain optical coherence tomography. Semin Ophthalmol. 2013; 28:97–102.

4. Yoon SW. Kang SM. Comparison of RNFL thickness among normal, glaucoma suspect and glaucoma in children. J Korean Ophthalmol Soc. 2009; 50:113–9.

5. Huynh SC. Wang XY. Rochtchina E. Mitchell P. Peripapillary retinal nerve fiber layer thickness in a population of 6-year-old children: findings by optical coherence tomography. Ophthalmology. 2006; 113:1583–92.

6. Salchow DJ. Oleynikov YS. Chiang MF, et al. Retinal nerve fiber layer thickness in normal children measured with optical coherence tomography. Ophthalmology. 2006; 113:786–91.

7. Ahn HC. Son HW. Kim JS. Lee JH. Quantitative analysis of retinal nerve fiber layer thickness of normal children and adolescents. Korean J Ophthalmol. 2005; 19:195–200.

8. Song JH. Kim E. Yoo JM. Analysis of RNFL thickness and optic nerve head measured with OCT in children. J Korean Ophthalmol Soc. 2007; 48:1346–53.

9. Cho YK. Lee YC. Lee SY. Factors mediating effects on the retinal nerve fiber layer thickness in normal children. J Korean Ophthalmol Soc. 2008; 49:98–103.

10. Kang KD. Abdul Majid AS. Kim YD, et al. Retinal nerve fiber layer thickness in children with glaucoma. J Korean Ophthalmol Soc. 2009; 50:887–92.

11. Shin JW. Uhm KB. Seong M. Lee DE. Retinal nerve fiber layer volume measurements in healthy subjects using spectral domain optical coherence tomography. J Glaucoma. 2014; 23:567–73.

12. Schuman JS. Hee MR. Puliafito CA, et al. Quantification of nerve fiber layer thickness in normal and glaucomatous eyes using optical coherence tomography. Arch Ophthalmol. 1995; 113:586–96.

13. Kanamori A. Nakamura M. Escano MF, et al. Evaluation of the glaucomatous damage on retinal nerve fiber layer thickness measured by optical coherence tomography. Am J Ophthalmol. 2003; 135:513–20.

14. Chi QM. Tomita G. Inazumi K, et al. Evaluation of the effect of aging on the retinal nerve fiber layer thickness using scanning laser polarimetry. J Glaucoma. 1995; 4:406–13.

15. Varma R. Bazzaz S. Lai M. Optical tomography-measured retinal nerve fiber layer thickness in normal latinos. Invest Ophthalmol Vis Sci. 2003; 44:3369–73.

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

17. Dichtl A. Jonas JB. Naumann GO. Retinal nerve fiber layer thickness in human eyes. Graefes Arch Clin Exp Ophthalmol. 1999; 237:474–9.

18. Alamouti B. Funk J. Retinal thickness decreases with age: an OCT study. Br J Ophthalmol. 2003; 87:899–901.

19. Leung MM. Huang RY. Lam AK. Retinal nerve fiber layer thickness in normal Hong Kong Chinese children measured with optical coherence tomography. J Glaucoma. 2010; 19:95–9.

20. Budenz DL. Fredette MJ. Feuer WJ. Anderson DR. Reproducibility of peripapillary retinal nerve fiber thickness measurements with stratus OCT in glaucomatous eyes. Ophthalmology. 2008; 115:661–6.

Figure 1.

A process for measuring retinal nerve fiber layer (RNFL) thickness of each pixel in the RNFL thickness map. The RNFL thickness map in the 6 × 6 mm² (540 × 540 pixels) parapapillary area is converted to RGB color information (red arrow). The color scale bar is also converted to red, green and blue (RGB) color format (black arrow). Then, each color pixel (blue and violet boxes) in the RNFL thickness map is compared with the RGB dataset (black box) of the color scale bar, and the RGB difference is calculated. We define RGB difference as (Red map - Red bar)² + (Green map - Green bar)² + (Blue map - Blue bar)². Each different minimal RGB position (pink and green boxes) is selected in the color scale bar and translated to the corresponding numeric RNFL thickness measurement. SD-OCT = spectral domain optical coherence tomography.

Figure 2.

Three-dimensional (3-D) structure of retinal nerve fiber layer (RNFL). (A) 3-D RNFL structure as the integral of a number of cube pixels. (B) The RNFL volume as the sum of ‘(6/540) mm × (6/540) mm × (RNFL thickness of corresponding pixel/1,000) mm’ within the measuring area. (C) RNFL volume between the 2.5- and 5-mm diameter circles, and RNFL thickness on the 3.4-mm circle.

Figure 3.

Retinal nerve fiber layer (RNFL) volume in children according to age. (A) Total mean RNFL volume. (B) Superior quadrant RNFL volume. (C) Nasal quadrant RNFL volume. (D) Inferior RNFL volume. (E) Temporal RNFL volume. ∗Correlation coefficient; †Statistical significance was tested using Person’s correlation test.

Table 1.

Study characteristics

Age (years)	10.03 ± 3.39
Sex (male/female)	30/24
Visual acuity	0.81 ± 0.28
Refractive error (dipoters)	-0.15 ± 1.13
Intraocular pressure (mm Hg)	13.42 ± 5.21

Values are presented as mean ± SD unless otherwise indicated.

Table 2.

RNFL volume and thickness based on quadrant in normal children and correlations between measurements

	RNFL volume (mm³)	RNFL thickness (μm)	R^∗
Total mean	1.48 ± 0.09	107.11 ± 7.19	0.980
Superior	0.45 ± 0.04	130.61 ± 12.16	0.953
Nasal	0.29 ± 0.04	77.89 ± 11.36	0.545
Inferior	0.46 ± 0.03	133.18 ± 11.11	0.932
Temporal	0.29 ± 0.04	86.81 ± 10.43	0.514

Values are presented as mean ± SD unless otherwise indicated.

RNFL = retinal nerve fiber layer.

^∗ Pearson’s correlation analysis; all correlation is significant at <0.01 level of p-value.

Table 3.

Analysis of RNFL change in children according to age

Variables	4≤~<8 years	8≤~ < 12 years	12≤~<15 years	p-value^∗	p-value^†
Mean age (years)	6.80 ± 1.47	10.01 ± 1.58	13.04 ± 1.66
Number (eyes)	25	27	27
RNFL volume (mm³)
Total mean	1.49 ± 0.09	1.51 ± 0.09	1.45 ± 0.08	0.063	0.081
Superior quadrant	0.45 ± 0.04	0.46 ± 0.04	0.43 ± 0.04	0.065	0.141
Nasal quadrant	0.29 ± 0.04	0.29 ± 0.04	0.28 ± 0.04	0.891	0.630
Inferior quadrant	0.46 ± 0.03	0.46 ± 0.03	0.45 ± 0.03	0.116	0.222
Temporal quadrant	0.29 ± 0.04	0.29 ± 0.03	0.28 ± 0.04	0.088	0.057
RNFL thickness (μm)
Total mean	108.04 ± 7.02	108.63 ± 7.39	104.32 ± 6.22	0.075	0.068
Superior quadrant	131.36 ± 10.75	133.96 ± 12.36	126.16 ± 11.72	0.083	0.124
Nasal quadrant	78.32 ± 13.51	78.59 ± 10.62	75.64 ± 11.61	0.471	0.242
Inferior quadrant	134.24 ± 10.89	134.67 ± 10.32	129.96 ± 11.60	0.323	0.187
Temporal quadrant	88.20 ± 9.46	87.30 ± 9.70	85.36 ± 11.69	0.241	0.082

Values are presented as mean ± SD unless otherwise indicated.

RNFL = retinal nerve fiber layer.

^∗ Kruskal-Wallis test;

^† Jonckheere-Terpstra test.

Table 4.

Mean RNFL volume and thickness according to sex

Gender	Size (eyes)	Age (years)	RNFL volume (mm³)					RNFL thickness (μm)
Gender	Size (eyes)	Age (years)	Total mean	Superior	Nasal	Inferior	Temporal	Total mean	Superior	Nasal	Inferior	Temporal
Male	45	10.11 ± 3.21	1.48 ± 0.09	0.45 ± 0.38	0.29 ± 0.03	0.45 ± 0.03	0.29 ± 0.04	107.00 ± 7.24	130.78 ± 12.50	79.40 ± 10.78	132.50 ± 110.19	85.18 ± 9.43
Female	34	9.91 ± 3.67	1.49 ± 0.09	0.45 ± 0.04	0.29 ± 0.04	0.46 ± 0.04	0.29 ± 0.04	107.26 ± 7.22	130.38 ± 11.88	75.88 ± 11.95	134.06 ± 12.32	88.97 ± 11.40
p-value^∗		0.798	0.793	0.948	0.947	0.582	0.885	0.872	0.887	0.175	0.543	0.110

Values are presented as mean ± SD unless otherwise indicated.

RNFL = retinal nerve fiber layer.

^∗ Independent t-test.

Table 5.

Comparison of studies reporting optical coherence tomography-measured RNFL in normal children

Author	Age range (years)	Size (eyes)	RNFL thickness (μm)
Author	Age range (years)	Size (eyes)	Mean	Superior	Nasal	Inferior	Temporal
Huynh et al⁵	6	1,369	103.7 ± 11.4	129.5 ± 20.6	81.7 ± 19.6	127.8 ± 20.5	75.7 ± 14.7
Salchow et al⁶	4-17	92	107.0 ± 11.1	135.4 ± 19.3	83.0 ± 18.0	136.9 ± 16.9	72.5 ± 13.4
Ahn et al⁷	9-18	72	105.5	134	70	132	87.8
Song et al⁸	5-14	200	104.67 ± 9.07	131.84 ± 18.71	73.85 ± 14.26	133.87 ± 18.58	78.49 ± 12.91
Yoon and Kang⁴	5-15	94	110.8 ± 10.1	140.1 ± 17.5	79.9 ± 14.5	134.1 ± 14.8	89.2 ± 16.8
Kang et al¹⁰	6-18	127	105.39 ± 9.22	131.26 ± 14.09	78.0 ± 15.2	134.34 ± 12.91	81.31 ± 17.2
Cho et al⁹	4-17	148	106.39 ± 12.8	135.3 ± 20.6	71.9 ± 20.8	130.9 ± 23.0	86.3 ± 18.9
Lee et al (present)	4-15	79	107.11 ± 7.19	130.61 ± 12.16	77.89 ± 11.36	133.18 ± 11.11	86.81 ± 10.43
			RNFL volume (mm³)
Lee et al (present)	4-15	79	1.48 ± 0.09	0.45 ± 0.04	0.29 ± 0.04	0.46 ± 0.03	0.29 ± 0.04

Values are presented as mean ± SD unless otherwise indicated.

RNFL = retinal nerve fiber layer.

TOOLS

Similar articles