Background This study aims to investigate the choroidal thickness and choroidal vascular density parameters and their correlation with severity of diabetic retinopathy (DR) in diabetes mellitus (DM) patients. Methods An observational cross-sectional study was conducted of 104 eyes, which were divided into 4 groups: Healthy controls (n = 38), DM with no DR eyes (n = 22), panretinal photocoagulation-untreated non-proliferative DR eyes (PRP-untreated NPDR eyes) (n = 24), PRP-untreated proliferative DR eyes (PRP-untreated PDR eyes) (n = 20). Optical coherence tomography (OCT) was performed. The total choroidal area (TCA), stromal area (SA), the luminal areas (LA) and the ratio of the luminal to choroidal area (L/C ratio) were compared. The choroidal parameters were also compared between PRP untreated and PRP-treated DR eyes. Results The L/C ratio values were 0.68 ± 0.06 in controls and 0.63 ± 0.04 in DM eyes (P < 0.001). But there were no statistically significant differences in retinal nerve fiber layer (RNFL) thickness, retinal thickness and subfoveal choroidal thickness (SCT) measurements between the two groups (P = 0.407, P = 0.654 and P = 0.849; respectively). The vessel density values were significantly different in DM with no DR eyes, PRP-untreated NPDR eyes and PRP-untreated PDR eyes (P < 0.001 for SCT, TCA and SA). The L/C ratio values in the three groups were significant different (P = 0.019). There was no significant difference in SCT, TCA, LA, SA and the L/C ratio between PRP-untreated and PRP-treated DR eyes. Conclusion Eyes of patients with DM showed the L/C ratio decreased compared with normal controls. The SCT increased, but L/C ratio significantly decreased with severity of DR eyes compared with DM and normal eyes. Changes in the L/C ratio may predict DR development before they are otherwise evident clinically. Choroidal blood flow deficit can be an early pathologic change in DR. Key Words Diabetic retinopathy; choroidal vascular density parameter; choroid; macular

Background This study aimes to investigate the choroidal thickness and choroidal vascularity index (CVI) and their correlation with severity of diabetic retinopathy (DR) in diabetes mellitus (DM) patients. Methods An observational cross-sectional study was conducted of 104 eyes, which were divided into 4 groups: Healthy controls (n = 38), DM with no DR eyes (n = 22), non-proliferative DR (NPDR) eyes (n = 24), proliferative DR (PDR) eyes (n = 20). Optical coherence tomography (OCT) was performed. The total choroidal area (TCA), stromal area (SA), the luminal areas (LA) and CVI were compared. Results The CVI values was 67.53 ± 6.20 in controls and 63.43 ± 4.47 in DM eyes (P < 0.001). But there were no statistically significant differences in retinal nerve fiber layer (RNFL), retinal thickness and subfoveal choroidal thickness (SCT) measurements between the two groups (P = 0.407, P = 0.654 and P = 0.849; respectively). The vessel density values were significantly different in DM with no DR eyes, NPDR eyes and PDR eyes. (P < 0.001 for SCT, TCA and SA). The CVIs in the three groups were significant different CVI (P = 0.019). Conclusion Eyes of patients with DM showed decreased CVI compared with normal controls. Choroidal thickness and CVI significantly increased with severity of DR eyes compared with DM eyes and normal. Changes in CVI may predict DR development or recurrence before they are otherwise evident clinically. Choroidal blood flow deficit can be an early pathologic change in DR.

Background This study aims to investigate the choroidal thickness and choroidal vascular density parameters and their correlation with severity of diabetic retinopathy (DR) in diabetes mellitus (DM) patients. Methods An observational cross-sectional study was conducted of 104 eyes, which were divided into 4 groups: Healthy controls (n = 38), DM with no DR eyes (n = 22), non-proliferative DR (NPDR) eyes (n = 24), proliferative DR (PDR) eyes (n = 20). Optical coherence tomography (OCT) was performed. The total choroidal area (TCA), stromal area (SA), the luminal areas (LA) and the ratio of the luminal to choroidal area(L/C ratio) were compared. The choroidal parameters were also compared between panretinal photocoagulation (PRP) untreated and PRP-treated DR eyes. ResultsThe L/C ratio values was 0.68 ± 0.06 in controls and 0.63 ± 0.04 in DM eyes (P < 0.001). But there were no statistically significant differences in retinal nerve fiber layer (RNFL) thickness, retinal thickness and subfoveal choroidal thickness (SCT) measurements between the two groups (P = 0.407, P = 0.654 and P = 0.849; respectively). The vessel density values were significantly different in DM with no DR eyes, PRP-untreated NPDR eyes and PRP-untreated PDR eyes (P < 0.001 for SCT, TCA and SA). The L/C ratio in the three groups were significant different (P = 0.019). There was no significant difference in SCT, TCA, LA, SA and the L/C ratio between PRP-untreated and PRP-treated DR eyes.Conclusion Eyes of patients with DM showed the L/C ratio decreased compared with normal controls.SCT increased, but the L/C ratio significantly decreased with severity of DR eyes compared with DM eyes and normal. Changes in the L/C ratio may predict DR development before they are otherwise evident clinically. Choroidal blood flow deficit can be an early pathologic change in DR. Key Words Diabetic retinopathy; choroidal vascular density parameter; choroid; macular Background The chronic hyperglycemia of diabetes mellitus (DM) can cause microvascular abnormalities [1] and complications of eyes [2] . It affects the retinal circulation and the choroidal vasculature. Diabetic retinopathy (DR) is one of the most severe complications of DM which can cause permanent visual impairment and affect the quality of life [3,4] . DR is gradually occurring with the development of DM.But due to the limitations of clinical diagnostic techniques, the pathological changes of DR have

Background This study aims to compare the levels of intraocular cytokines between Fuchs uveitis syndrome (FUS) eyes and the senile cataract eyes. The association between inflammatory cytokine levels and cataract severity in FUS is evaluated to find the possible mechanism of cataract in FUS eyes.Methods A retrospective study of 28 eyes with FUS was performed. Auxiliary examinations were performed, including ophthalmic examinations, laser flare-cell photometry, and levels of inflammatory cytokines in the aqueous humor were measured. The control group included 25 eyes with senile cataract. Data on the aqueous humor inflammatory cytokines were compared between the two groups. The association between the aqueous humor cytokine levels and severity of posterior subcapsular cataract was assessed.Results There were 28 eyes with FUS in 27 patients. Unilateral involvement was noted in 26 patients (96.30%). Stellate keratic precipitates (KPs) were noted in 16 eyes (57.14%). Heterochromia was observed in 21.43% of affected eyes. Posterior subcapsular cataract was observed in 16 of the 28 eyes. Eyes with FUS had significantly higher aqueous humor (AH) cytokine levels (VEGF, bFGF, IL-6, IL-8 and IL-10) compared with the control eyes (P<0.05). There was a statistically significant positive correlation between the severity of cataract and IL-6 and IL-8 levels in the AH (τ = 0.675 and 0.793, respectively; P = 0.001, P<0.001, respectively).Conclusions Expression of VEGF, bFGF, IL-6, IL-8 and IL-10 in the AH of FUS patients was significantly higher than in senile cataract eyes, and the aqueous humor levels of IL-6 and IL-8 were significantly positively associated with the severity of posterior subcapsular cataract. Our results imply that an inflammation mechanism may be involved in the early development of cataract in FUS.

Background This study aims to investigate the choroidal thickness and choroidal vascular density parameters and their correlation with severity of diabetic retinopathy (DR) in diabetes mellitus (DM) patients. Methods An observational cross-sectional study was conducted of 104 eyes, which were divided into 4 groups: Healthy controls (n = 38), DM with no DR eyes (n = 22), non-proliferative DR (NPDR) eyes (n = 24), proliferative DR (PDR) eyes (n = 20). Optical coherence tomography (OCT) was performed. The total choroidal area (TCA), stromal area (SA), the luminal areas (LA) and the ratio of the luminal to choroidal area were compared. Results The ratio of the luminal to choroidal area values was 67.53 ± 6.20 in controls and 63.43 ± 4.47 in DM eyes (P < 0.001). But there were no statistically significant differences in retinal nerve fiber layer (RNFL), retinal thickness and subfoveal choroidal thickness (SCT) measurements between the two groups (P = 0.407, P = 0.654 and P = 0.849; respectively). The vessel density values were significantly different in DM with no DR eyes, NPDR eyes and PDR eyes. (P < 0.001 for SCT, TCA and SA). The ratio of the luminal to choroidal area in the three groups were significant different(P = 0.019). Conclusion Eyes of patients with DM showed decreased ratio of the luminal to choroidal area compared with normal controls. Choroidal thickness and the ratio of the luminal to choroidal area significantly increased with severity of DR eyes compared with DM eyes and normal. Changes in the ratio of the luminal to choroidal area may predict DR development or recurrence before they are otherwise evident clinically. Choroidal blood flow deficit can be an early pathologic change in DR.