Correlation between laser speckle flowgraphy and optical coherence tomography angiography measurements in normal and glaucomatous eyes

Figures & data

Figure 1 (A) ONH blood flow acquired by LSFG. “1” represents region of interest inside ONH. (B) The black area shows MBR-T and the white area shows MBR-V. (C) CpVD “area a” represents a vascular density of 250-μm-wide elliptical annulus around the optic disc. IpVD “area b” represents a vascular density of 1.5×1.5-mm scan field centered on the ONH.

Abbreviations: ONH, optic nerve head; LSFG, laser speckle flowgraphy; MBR-T, tissue mean blur rate; MBR-V, vascular mean blur rate; cpVD, circumpapillary vessel density; ipVD, intra-papillary vessel density.

Table 1 Age, sex, MD, and refractive error in each group

	Normal	Mild glaucoma	Moderate to severe glaucoma	P-value
Number of subjects	14	16	16
Age (years)	64.0±14.0	60.7±9.3	60.6±13.6	0.75^a
Sex (male/female)	6/8	8/8	8/8	0.94^b
MD (dB)	0.6±1.4	−4.1±1.8	−14.1±7.0	<0.001^a
Refractive error (D)	−0.6±1.7	−2.5±2.3	−2.1±2.7	0.13^a

Notes: Continuous variables are presented as mean ± SD. (^a and ^b) Indicate one-way ANOVA and Fisher’s exact test, respectively.

Abbreviation: MD, mean deviation.

Table 2 MBR-V and cpVD in various layers

		Normal	Mild glaucoma	Moderate to severe glaucoma	P-value
Number of subjects		14	16	16
MBR-V		40.9±4.6	37.3±3.9	36.9±6.2	0.07
	RPCP	20.4±7.7	20.6±9.0	19.1±9.9	0.46
cpVD	Choroid	5.2±3.9	8.3±6.8	5.4±4.7	0.20
	Lamina cribrosa	26.4±8.8	27.9±8.0	23.3±6.4	0.24

Notes: Data are presented as mean ± SD. P-values were calculated by one-way ANOVA.

Abbreviations: MBR-V, vascular mean blur rate; cpVD, circumpapillary vessel density; RPCP, radial peripapillary capillary plexus.

Table 3 Intra-papillary vessel density in various layers

		Normal	Mild glaucoma	Moderate to severe glaucoma	P-value
Number of subjects		14	16	16
	RPCP	14.9±6.6	13.5±7.0	13.4±5.9	0.79
ipVD	Outer layer of retina	21.4±6.8	21.8±7.1	17.6±7.4	0.20
	Choroid	16.2±6.7	19.6±6.4	16.0±5.7	0.19
	Lamina cribrosa	11.0±5.8	14.9±6.5	10.4±6.1	0.10

Notes: Data are presented as mean ± SD. P-values were calculated by one-way ANOVA.

Abbreviations: ipVD, intra-papillary vessel density; RPCP, radial peripapillary capillary plexus.

Figure 2 (A) ONH tissue blood flow (MBR-T, mean ± standard error) changes in normal subjects and patients in each glaucoma stage. P<0.001 (one-way ANOVA), *P<0.01 (Dunnett’s test). (B) Retinal outer layer cpVD changes (mean ± standard error) in each glaucoma stage. P=0.02 (one-way ANOVA), *P<0.01 (Dunnett’s test).

Abbreviations: n.s, not significant; ONH, optic nerve head; MBR-T, tissue mean blur rate; cpVD, circumpapillary vessel density.

Table 4 Correlation between cpVD and MBR-T or MBR-V in various layers

	RPCP		Outer layer of retina		Choroid		Lamina cribrosa
	r	P	r	P	r	P	r	P
MBR-T	0.28	0.07	0.49	0.0005	0.03	0.81	0.23	0.11
MBR-V	0.10	0.51	0.13	0.36	0.13	0.37	0.28	0.07

Notes: P-values and correlation coefficients (R) were calculated by univariate regression analysis.

Abbreviations: cpVD, circumpapillary vessel density; MBR-T, tissue mean blur rate; MBR-V, vascular mean blur rate; RPCP, radial peripapillary capillary plexus.

Table 5 Correlation between ipVD and MBR-T or MBR-V in various layers

	RPCP		Outer layer of retina		Choroid		Lamina cribrosa
	r	P	r	P	r	P	r	P
MBR-T	0.10	0.46	0.07	0.60	0.17	0.23	0.08	0.55
MBR-V	0.20	0.16	0.01	0.93	0.17	0.23	0.15	0.31

Notes: P-values and correlation coefficients (R) were calculated by univariate regression analysis.

Abbreviations: ipVD, intra-papillary vessel density; MBR-T, tissue mean blur rate; MBR-V, vascular mean blur rate; RPCP, radial peripapillary capillary plexus.

Figure 3 Correlation between retinal outer layer cpVD and MBR-T. P=0.0005, r=0.49 (univariate regression analysis).

Abbreviations: MBR-T, tissue mean blur rate; cpVD, circumpapillary vessel density.