Altered spontaneous brain activity patterns in strabismus with amblyopia patients using amplitude of low-frequency fluctuation: a resting-state fMRI study

Figures & data

Table 1 Demographics and clinical measurements of SA and HC groups

	SA	HC	t-value	P-value
Male/female	6/10	6/10	N/A	>0.99
Age (years)	24.50±5.91	24.94±5.23	−0.222	0.615
Handedness	16 R	16 R	N/A	>0.99
Duration (years)	18.19±9.85	N/A	N/A	N/A
Esotropia/exotropia	5/11	N/A	N/A	N/A
Spherical equivalent refractive error (diopters)	1.22±0.56	1.25±0.67	−0.365	0.741
Mean ± SD (range)	−2.75–1.75	−2.75–2.00	N/A	N/A
Angle of strabismus (PD)	26.25±12.71	N/A	N/A	N/A
Best-corrected VA-AE	0.53	−0.05±0.08	6.149	<0.001
Best-corrected VA-FE	−0.03±0.09	−0.01±0.07	−0.651	0.185

Notes: Independent t-tests comparing the two groups (P<0.05 represented statistically significant differences). Data shown as mean SD or n.

Abbreviations: AE, amblyopic eye; FE, fellow eye; HC, healthy control; N/A, not applicable; PD, prism diopter; R, right; SA, strabismus with amblyopia; VA, visual acuity.

Table 2 Brain areas with significantly different ALFF values between groups

Conditions	L/R	Brain regions	BA	MNI coordinates			Peak voxels	t-value
				X	Y	Z
SAs > HCs
1	R	Superior frontal gyrus	10	−12	60	6	41	4.6552
2	R	Precuneus		27	−75	39	144	4.8382
3	L	Cuneus	19	−24	−87	27	48	5.1766
4	B	Precentral gyrus	6	−3	−21	78	648	9.9577
SAs < HCs
1	L	Cerebellum posterior lobe		−33	−60	−42	88	−4.4430
2	L	Thalamus		−18	−15	12	78	−6.3723
3	R	Thalamus		12	−21	12	101	−6.0901
4	L	Middle frontal gyrus	9	−48	15	30	89	−5.6140

Note: The statistical threshold was set at voxel level with P<0.05 for multiple comparisons using Gaussian random field theory voxels with P<0.01 and cluster size >40 voxels, AlphaSim corrected.

Abbreviations: ALFF, amplitude of low-frequency fluctuation; BA, Brodmann area; B, bilateral; HC, healthy control; L, left; MNI, Montreal Neurological Institute; R, right; SA, strabismus with amblyopia.

Figure 1 Spontaneous brain activity in the SA and HC groups.

Notes: (A) The different ALFF regions between the SA and HC groups. (B) Significant differences of brain activity in cerebrum. (C) Significant differences of brain activity in cerebellum. The red regions indicate higher ALFF values, and the blue regions imply lower ALFF values (P<0.05, AlphaSim corrected, cluster size >40).
Abbreviations: ALFF, amplitude of low-frequency fluctuation; HC, healthy control; L, left; R, right; SA, strabismus with amblyopia.

Figure 2 The mean ALFF values between the SA and HC groups.

Abbreviations: ALFF, amplitude of low-frequency fluctuation; BPCG, bilateral precentral gyrus; HC, healthy control; LC, left cuneus; LCPL, left cerebellum posterior lobe; LMFG, left middle frontal gyrus; LT, left thalamus; RPC, right precuneus; RSFG, right superior frontal gyrus; RT, right thalamus; SA, strabismus with amblyopia.

Figure 3 ROC curve analysis of the mean ALFF values for altered brain regions in SA group.

Notes: (A) The area under the ROC curve were 0.871, (P<0.001; 95% CI: 0.734–1.000) for RSFG, RPC 0.949 (P<0.001; 95% CI: 0.874–1.000), LC 0.898 (P<0.001; 95% CI: 0.795–1.000), BPCG 0.957 (P<0.001; 95% CI: 0.879–1.000) (SAs > HCs). (B) The area under the ROC curve were 0.914 (P<0.001; 95% CI: 0.815–1.000) for LCPL, LT 0.938 (P<0.001; 95% CI: 0.859–1.000), RT 0.938 (P<0.001; 95% CI: 0.845–1.000), LMFG 0.973 (P<0.001; 95% CI: 0.922–1.000) (SAs < HCs).
Abbreviations: ALFF, amplitude of low-frequency fluctuation; AUC, area under the curve; BPCG, bilateral precentral gyrus; HC, healthy control; LC, left cuneus; LCPL, left cerebellum posterior lobe; LMFG, left middle frontal gyrus; LT, left thalamus; ROC, receiver operating characteristic; RPC, right precuneus; RSFG, right superior frontal gyrus; RT, right thalamus; SA, strabismus with amblyopia.