RE-PERG, a new paradigm for glaucoma diagnosis, in myopic eyes

Figures & data

Figure 1 Five consecutive blocks of steady-state pattern electroretinogram (time domain – 512 samples).

Figure 2 Five consecutive blocks of steady-state pattern electroretinogram (frequency domain – rps).

Table 1 Demographic and relevant ocular characteristic of study participants

	Patients (n=112 cases)
	GP (n=50)		NC (n=35)		My (n=19)		P-value*
	Mean	SD ±	Mean	SD ±	Mean	SD ±	GP vs NC	GP vs My	NC vs My
Age	67.4	11.1	65.2	9.9	64.0	7.7	P=0.358	P=0.154	P=0.618
Male (%)	50		51		68		P=0.89**	P=0.12**	P=0.16**
MD (db)	−2.5	1.91	0.35	1.00	−1.27	1.26	P<0.001	P=0.002	P<0.001
PSD (db)	2.66	2.05	1.29	0.36	1.45	0.27	P<0.001	P=0.002	P=0.047
RNFL (µm)	75.84	13.34	92.03	8.93	85.5	10..5	P<0.001	P=0.007	P=0.009
GCC (µm)	67.26	11.70	80.14	4.94	79.3	9.4	P<0.001	P<0.001	P=0.654
ssPERG Amp (µV)	1.36	0.14	1.67	0.15	1.41	0.2	P<0.001	P=0.292	P<0.001
ssPERG SD ph (SD)	0.30	0.14	0.10	0.04	0.12	0.03	P<0.001	P<0.001	P=0.066

Notes: *One-way analysis of variance (Bonferroni corrected); **chi-square.

Abbreviations: MD, mean deviation; PSD, pattern standard deviation; RNFL, retinal nerve fiber layer thickness; GCC, ganglion cell complex; ssPERG SDph, steady-state intrinsic phase variability; ssPERG Amp, steady-state pattern electroretinogram mean amplitude value; GP, glaucomatous patients; NC, normal controls; My, myopic subjects.

Table 2 Clinical characteristics of myopic subjects

									Normality range
	Gender	Age	ssPERG Amp	ssPERG SDph	MD	PSD	RNFL	GCC	ssPERG Amp	ssPERG SDph
#1	m	44	1.42	0.09	−0.4	1.8	88	72	a	n
#2	m	74	1.48	0.13	−0.5	1.3	74	64	a	n
#3	m	78	1.36	0.1	−2.01	1.2	88	70	a	n
#4	m	68	1.15	0.12	−3.5	1.5	104	91	a	n
#5	m	60	1.18	0.11	−3.21	1.55	101	91	a	n
#6	f	74	1.19	0.12	−2.4	1.88	87	71	a	n
#7	f	56	1.09	0.1	−2.13	1.25	75	69	a	n
#8	m	55	1.13	0.11	−1.5	1.24	79	77	a	n
#9	f	57	1.54	0.11	0.35	1.88	76	77	n	n
#10	f	57	1.56	0.14	−2.89	1.24	98	92	n	n
#11	f	68	1.15	0.16	−1.4	1.4	102	84	a	a
#12	m	60	1.51	0.11	−2.1	1.53	99	90	n	n
#13	m	68	1.53	0.16	0.93	1.46	84	80	n	a
#14	m	65	1.44	0.07	−3.22	1.7	78	79	a	n
#15	m	61	1.55	0.07	−1.52	1.21	70	68	n	n
#16	m	69	1.53	0.12	−0.06	1.34	72	55	n	n
#17	f	62	1.5	0.15	−0.45	1.34	70	87	a	a
#18	m	57	1.75	0.2	1	1.4	100	90	n	a
#19	m	55	1.76	0.17	0.4	1.5	99	90	n	a

Abbreviations: ssPERG Amp, steady-state pattern electroretinogram mean amplitude value; ssPERG SDph, standard deviation of steady-state PERG phase; MD, mean deviation; PSD, pattern standard deviation; RNFL, retinal nerve fiber layer thickness; GCC, ganglion cell complex in 19 Myopic subjects.

Table 3 Pearson correlation coefficient (CC) and significance level P (SL-P) between mean deviation (MD) pattern standard deviation (PSD), retinal Nerve fiber layer thickness (RNFL)*, ganglion cell complex (GCC)*, steady-state pattern electroretinogram mean amplitude value (ssPERG Amp)*, standard deviation of steady-state PERG phase (ssPERG SDph) in all participants

		MD	PSD	GCC	RNFL	Amplitude	SD Phase
MD	CC		−0.59	0.55	0.52	0.72	−0.63
	SL-P		<0.0001	<0.0001	<0.0001	<0.0001	<0.0001
PSD	CC	−0.59		−0.34	−0.33	−0.34	0.41
	SL-P	<0.0001		0.0005	0.0005	0.0004	<0.0001
GCC	CC	0.55	−0.34		0.81	0.49	−0.52
	SL-P	<0.0001	0.0005		<0.0001	<0.0001	<0.0001
RNFL	CC	0.52	−0.33	0.81		0.48	−0.47
	SL-P	<0.0001	0.0005	<0.0001		<0.0001	<0.0001
ssPERG Amp	CC	0.72	−0.34	0.49	0.48		−0.27
	SL-P	<0.0001	0.0004	<0.0001	<0.0001		0.006
ssPERG SDph	CC	−0.63	0.41	−0.52	−0.5	−0.55
	SL-P	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001

Notes: *RNFL, GCC, and ssPERG Amp were converted to a logarithmic scale (dB) in association with visual field indices.

Table 4 Pearson correlation coefficient (CC) and significance level P (SL-P) between mean deviation (MD) pattern standard deviation (PSD), retinal nerve fiber layer thickness (RNFL)*, ganglion cell complex (GCC)*, steady-state pattern electroretinogram mean amplitude value (ssPERG Amp)*, standard deviation of steady-state PERG phase (ssPERG SDph) in myopic and glaucomatous patients

		MD	PSD	GCC	RNFL	Amplitude	SD Phase
MD	CC		−0.19	−0.07	−0.12	0.48	−0.06
	SL-P		0.06	0.63	0.38	0.001	0.67
PSD	CC	−0.19		0.01	0.14	−0.15	−0.09
	SL-P	0.06		0.93	0.31	0.28	0.54
GCC	CC	−0.07	0.01		0.65	−0.01	0.24
	SL-P	0.63	0.92		<0.001	0.93	0.08
RNFL	CC	−0.12	0.14	0.65		0.03	0.22
	SL-P	0.38	0.31	<0.001		0.84	0.11
ssPERG Amp	CC	0.48	−0.15	−0.01	0.03		−0.14
	SL-P	0.001	0.28	0.93	0.84		0.32
ssPERG SDph	CC	−0.06	−0.09	0.24	0.22	−0.14
	SL-P	0.67	0.54	0.08	0.11	0.32

Notes: *RNFL, GCC, and ssPERG Amp were converted to a logarithmic scale (dB) in association with visual field indices.

Figure 3 Box-plot of amplitude values of steady-state perg in glaucoma patients, myopic subjects and normal control.Abbreviation: ssPERG Amp, steady-state pattern electroretinogram mean amplitude value.

Figure 4 Box-plot of intrinsic variability of the phase of steady-state perg in glaucoma patients, myopic subjects and normal control. Abbreviation: ssPERG SDph, standard deviation of steady-state pattern electroretinogram phase.

Table 5 (A) Receiver operating characteristics (ROCs) without myopic subjects. (B) ROCs myopic subjects included

	AUC	SE^a	95% CI^b	Specificity	95% CI^b
A
MD	0.83	0.05	0.738–0.906	71.79	48.72–89.74
PSD	0.78	0.05	0.683–0.867	62.56	33.33–84.62
GCC	0.79	0.05	0.685–0.868	54.36	28.45–77.55
RNFL	0.77	0.05	0.664–0.853	64.10	47.20–78.80
ssPERG Amp	0.86	0.04	0.765–0.924	82.10	66.50–92.50
ssPERG SDph	0.93	0.04	0.857–0.976	84.60	69.50–94.10
B
MD	0.76	0.05	0.671–0.842	84.48	72.6–92.7
PSD	0.79	0.05	0.701–0.865	77.59	64.7–87.5
GCC	0.77	0.04	0.676–0.846	81.03	68.6–90.1
RNFL	0.73	0.04	0.640–0.817	58.62	44.9–71.4
ssPERG Amp	0.76	0.05	0.664–0.837	70.69	57.3–81.9
ssPERG SDph	0.86	0.04	0.778–0.920	93.10	83.3–98.1

Notes: Data from these studies.^12,13,30 aDeLong et al, 1988. ^bBinomial exact.

Abbreviations: MD, mean deviation; PSD, pattern standard deviation; RNFL, retinal nerve fiber layer thickness; GCC, ganglion cell complex; ssPERG Amp, steady-state pattern electroretinogram mean amplitude value; ssPERG SDph, standard deviation of steady-state PERG phase.

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