Fig. 7

Correlations between the PD degenerative process and our results. a Correlation plot between LTS density score in the retina and the number of INL ChAT⁺ cells; Spearman correlation ρ = 0.437; P > 0.05 (no correlation). b Correlation plot between LTS density score in the retina and the number of GCL ChAT⁺ cells; Spearman correlation ρ = 0.269; P > 0.05 (no correlation). c Correlation plot between LTS density score in the retina and the number of DA-ChAT connections in the retina; Spearman correlation ρ =  − 0.045; P > 0.05 (no correlation). d Correlation plot between the number of DA cells in the retina and the number of INL ChAT⁺ cells at 2 mm from the optic nerve; Spearman correlation ρ = 0.760; P < 0.05. e Correlation plot between the number of DA cells in the retina and the number of INL ChAT⁺ cells at 4 mm from the optic nerve; Spearman correlation ρ = 0.835; P < 0.01. f Correlation plot between the number of DA cells in the retina and the number of INL ChAT⁺ cells at 6 mm from the optic nerve; Spearman correlation ρ = 0.694; P < 0.05. g Correlation plot between the number of DA cells in the retina and the number of bright INL ChAT⁺ cells at 2 mm from the optic nerve; Spearman correlation ρ = 0.746; P < 0.05. h Correlation plot between the number of DA cells in the retina and the number of bright INL ChAT⁺ cells at 4 mm from the optic nerve; Spearman correlation ρ = 0.729; P < 0.05. i Correlation plot between the number of DA cells in the retina and the number of bright INL ChAT⁺ cells at 6 mm from the optic nerve; Spearman correlation ρ = 0.778; P < 0.01. j Correlation plot between the number of DA cells in the retina and the number of INL ChAT⁺ cells; Spearman correlation ρ = 0.629; P > 0.05 (no correlation). k Correlation plot between the number of DA cells in the retina and the number of GCL ChAT⁺ cells; Spearman correlation ρ = 0.549; P > 0.05 (no correlation). l Correlation plot between the number of DA cells in the retina and the number of DA-ChAT connections in the retina; Spearman correlation ρ = 0.794; P < 0.05. Two-tailed Spearman correlation test. LTS: retinal Lewy-type synucleinopathy