Influence of the Size of the Foveal Avascular Zone on Functional and Morphological Parameters in Patients with Early-Stage Diabetic Retinopathy

Figures & data

Table 1 Demographic and Diabetes Related Data per Group (G1/G2) and Quartile (Q1/Q3)

	FAZ ≤ 0.35 mm^2 (G1)		FAZ > 0.35 mm^2 (G2)		t-test	FAZ ≤ 0.45 mm^2 (Q1)		FAZ ≥ 1.16 mm^2 (Q3)		t-test
	N	Mean ± SD	N	Mean± SD	p-value	N	Mean ± SD	N	Mean ± SD	p-value
Age [yo]	6	62.2 ± 18.7	30	61.2 ± 14.8	0.89	9	63 ± 15.3	9	55.7 ± 15.6	0.33
HbA1c [%]	5	6.8 ± 0.6	26	7.7 ± 1.6	0.2	8	7.6 ± 1.4	8	7.2 ± 0.8	0.44
DM dur. [y]	5	16.8 ± 6.6	26	21.4 ± 10.7	0.36	8	15.3 ± 6.2	8	17.9 ± 7.8	0.49
Insulin ther. [y]	3	9 ± 5.6	21	18 ± 9.9	0.14	6	8.8 ± 4.6	6	17 ± 10.4	0.18
Spherical equivalent	6	−0.3 ± 2.3	28	−0.2 ± 2.2	0.92	9	−0.3 ± 2.1	8	0.3 ± 1.8	0.49

Table 2 Functional and Morphological Data per Group (G1/G2) and Quartile (Q1/Q3)

	≤0.35 mm^2 (G1)		>0.35 mm^2 (G2)		t-test	≤0.45 mm^2 (Q1)		≥1.16 mm^2 (Q3)		t-test
	N	Mean ± SD	N	Mean ± SD	p-value	N	Mean ± SD	N	Mean ± SD	p-value
BCVA [letters]	6	83 ± 7.2	26	79.1 ± 7.3	0.25	9	83.4 ± 5.8	8	79.4 ± 8.6	0.28
BCVA [logMAR]		0.04		0.12			0.04		0.12
BChcVA [letters]	6	50.7 ± 6.1	27	47 ± 9.7	0.38	9	51.9 ± 5.2	8	44 ± 14.5	0.18
BClcVA [letters]	6	44.5 ± 6.7	27	37.4 ± 11.8	0.17	9	43.9 ± 5.6	8	34 ± 16.4	0.14
MS [db]	6	28.7 ± 1.4	29	26.4 ± 5.2	0.04	8	28.7 ± 1.3	9	27.3 ± 3.6	0.32
MD [db]	6	0.8 ± 1.4	29	2.8 ± 4.5	0.07	8	1 ± 1.3	9	2.2 ± 3.5	0.7
CPT [µm]	4	244.5 ± 29.2	30	251.4 ± 41	0.75	7	247.9 ± 29.6	9	257.7 ± 34	0.55
CST [µm]	4	281 ± 33.2	30	285.9 ± 27.2	0.74	7	283.4 ± 24.2	9	294 ± 25	0.41
TMV [mm^3]	4	8.4 ± 0.9	30	8.7 ± 0.7	0.4	7	8.5 ± 0.7	9	9.1 ± 0.7	0.12
CSV [mm^3]	4	0.2 ± 0.02	30	0.2 ± 0.02	0.67	7	0.2 ± 0.02	9	0.2 ± 0.02	0.31

Abbreviations: BCVA, best corrected visual acuity; CPT, central point thickness; CST, central subfield thickness; CSV, central subfield volume; TMV, total macular volume; BChcVA, best corrected high contrast visual acuity scores; BClcVA, best corrected low contrast visual acuity scores; MS, mean sensitivity; MD, mean defect.

Table 3 Pearson’s Correlation Coefficient PCC and p-values for Regression Analysis

Parameter correlated with FAZ	PCC	p-value
Age [yo]	−0.21	0.23
HbA1c [%]	0.02	0.92
Duration of DM [y]	−0.1	0.61
Duration of insulin therapy [y]	0.05	0.82
BCVA [letters]	−0.17	0.34
MS [db]	−0.04	0.8
MD [db]	0.05	0.74
CPT [µm]	0.21	0.23
CST [µm]	0.26	0.14
CSV [µm]	0.31	0.07

Abbreviations: BCVA, best corrected visual acuity; CPT, central point thickness; CST, central subfield thickness; CSV, central subfield volume; TMV, total macular volume; BChcVA, best corrected high contrast visual acuity scores; BClcVA, best corrected low contrast visual acuity scores; MS, mean sensitivity; MD, mean defect.

Figure 1 Mean FAZ versus high contrast visual acuity score (Pearson’s correlation coefficient −0.38; p=0.03).

Figure 2 Mean FAZ versus low contrast visual acuity score (Pearson’s correlation coefficient −0.41; p=0.02).

Figure 3 Mean FAZ versus total macular volume [mm³] (Pearson’s correlation coefficient 0.35; p=0.04).