Table 4. Comparison of the peripapillary retinal nerve fibre layer thickness between non-arteritic anterior ischaemic optic neuropathy eyes and normal fellow eyes.

	NAION eye	Fellow eye	Reduction rate (%)*	P value†
Average RNFL thickness	64.7 ± 12.3	93.0 ± 7.6	30.4	<0.001
Quadrant RNFL thickness
Superior	70.8 ± 22.6	111.9 ± 11.8	36.7	<0.001
Nasal	54.4 ± 10.0	67.3 ± 9.8	19.2	<0.001
Inferior	80.0 ± 23.5	124.2 ± 16.1	35.6	<0.001
Temporal	53.1 ± 12.1	68.9 ± 10.2	23.0	<0.001
Clock-hour RNFL thickness
11 o’clock	73.5 ± 25.2	119.0 ± 22.7	38.2	<0.001
12 o’clock	75.8 ± 27.4	114.0 ± 19.8	33.5	<0.001
1 o’clock	62.5 ± 17.3	103.0 ± 18.1	39.3	<0.001
2 o’clock	57.8 ± 14.8	78.1 ± 16.8	26.1	<0.001
3 o’clock	51.8 ± 9.5	60.3 ± 8.3	14.1	0.005
4 o’clock	53.1 ± 7.8	62.5 ± 10.8	15.0	0.001
5 o’clock	64.4 ± 16.1	98.2 ± 17.3	34.4	<0.001
6 o’clock	81.8 ± 28.9	136.4 ± 25.1	40.0	<0.001
7 o’clock	93.7 ± 29.6	138.2 ± 19.8	44.5	<0.001
8 o’clock	55.1 ± 14.3	69.5 ± 12.2	20.7	0.001
9 o’clock	48.8 ± 10.7	56.0 ± 8.1	13.0	0.004
10 o’clock	55.0 ± 17.7	81.1 ± 15.6	32.2	<0.001

(μm, mean ± SD)

RNFL = retinal nerve fibre layer, GCIPL = ganglion cell plus inner plexiform layer

NAION = non-arteritic anterior ischaemic optic neuropathy

*Reduction rate (%) = 100 × (RNFL thickness of the fellow eye–RNFL thickness of the NAION eye)/RNFL thickness of the fellow eye

† Axial length adjusted linear mixed model.