Differential association of elevated inflammatory cytokines with postoperative fibrous proliferation and neovascularization after unsuccessful vitrectomy in eyes with proliferative diabetic retinopathy

Figures & data

Table 1 Inclusion and exclusion criteria for patients

Criteria
Inclusion criteria
Age >20 years
Proliferative diabetic retinopathy
Tractional retinal detachment with active neovascularization within the FVMs
Repeated vitreous hemorrhage with active neovascularization
Refractory neovascular glaucoma
Exclusion criteria
Age >80 years
Previous history of ocular trauma or pars plana vitrectomy
Previous history of ocular surgery or panretinal photocoagulation within 6 months
Hematologic disease
Uremia
Previous chemotherapy
Epilepsy

Abbreviation: FVM, fibrovascular membrane.

Table 2 Demographics and surgical characteristics of PDR patients

Characteristic
Age, years	55.4±14.4
Sex
Male	6
Female	8
Duration of diabetes, years	12.4±5.9
Glycosylated hemoglobin, %	7.8±1.6
Photocoagulation spots	1,205±286
Operation time, min	83.3±39.7
Subgroups, n (%)
Anterior chamber neovascularization	1 (7)
Vitreous hemorrhage	4 (28)
Fibrovascular membrane	12 (86)
Traction retinal detachment	4 (29)
Panretinal photocoagulation	11 (79)
Presence or iatrogenic generation of retinal holes	13 (93)
Air tamponade at the first vitrectomy	12 (86)
SF6 gas tamponade at the first vitrectomy	1 (7)

Note: Data presented as mean ± SD unless otherwise indicated.

Abbreviations: PDR, proliferative diabetic retinopathy; SF6, sulfur hexafluoride.

Figure 1 Vitreous concentrations of MCP-1 (A), IL-6 (B), IL-8 (C), and VEGF (D) in the vitreous samples at the first vitrectomy in PDR patients, and the same vitrectomized PDR patients at the time of the reoperation.

Note: *P<0.001 (Wilcoxon matched-pairs signed-rank tests).
Abbreviations: PDR, proliferative diabetic retinopathy; NS, not significant.

Figure 2 Intravitreous levels of MCP-1, IL-6, IL-8, and VEGF at the time of reoperation vitrectomy and their correlations with the presence or absence of tractional retinal detachment (TRD) due to fibrous proliferation.

Notes: The correlation was determined by the Spearman coefficient of correlation. (A) Intravitreous level of MCP-1 in eyes with and without fibrous proliferation (*P<0.01). (B) Intravitreous level of IL-6 in eyes with and without fibrous proliferation (**P<0.05). (C) Intravitreous level of IL-8 in the presence or absence of fibrous proliferation (**P<0.05). (D) Intravitreous level of VEGF in the presence or absence of fibrous proliferation.
Abbreviation: NS, not significant.

Figure 3 Intravitreous levels of MCP-1, IL-6, IL-8, and VEGF at the time of reoperation vitrectomy and their correlations with the presence or absence of neovascular glaucoma (NVG) and/or anterior hyaloidal fibrovascular proliferation (AHFVP).

Notes: The correlation was determined by the Spearman coefficient of correlation. (A) Intravitreous level of MCP-1 in eyes with and without NVG and/or AHFVP. (B) Intravitreous level of IL-6 in eyes with and without NVG and/or AHFVP. (C) Intravitreous level of IL-8 according to the presence or absence of NVG and/or AHFVP. (D) Intravitreous level of VEGF according to the presence or absence of NVG and/or AHFVP (*P<0.05).
Abbreviation: NS, not significant.

Figure 4 Vitreous concentrations of MCP-1 (A), IL-6 (B), IL-8 (C), and VEGF (D) in patients with an idiopathic epiretinal membrane or a macular hole (nondiabetic controls; n=110), and also eyes with proliferative diabetic retinopathy (PDR; n=129), and proliferative vitreoretinopathy (PVR; n=24).

Notes: The horizontal lines are the mean values. *P<0.01, **P<0.001 (Mann–Whitney U test).

Table 3 Correlations among vitreous concentration of MCP-1, IL-6, IL-8 and VEGF in eyes with proliferative diabetic retinopathy (PDR) and proliferative vitreoretinopathy (PVR)

	PDR		PVR
	Correlation coefficient	P-value	Correlation coefficient	P-value
MCP-1 vs IL-6	0.7329	<0.0001	0.8078	<0.0001
MCP-1 vs IL-8	0.7648	<0.0001	0.7765	<0.0001
IL-6 vs IL-8	0.6174	<0.0001	0.5687	0.0037
VEGF vs IL-6	0.2493	0.0044	0.3876	0.0613
VEGF vs IL-8	0.3368	<0.0001	0.3229	0.1238
VEGF vs MCP-1	0.1295	0.1435	0.3296	0.1158