Vitreous levels of reactive oxygen species in proliferative diabetic retinopathy.
OBJECTIVE
To investigate vitreous levels of reactive oxygen species (ROS) in patients with proliferative diabetic retinopathy (PDR) and analyze ROS levels among different groups of PDR patients.


METHODS
Retrospective case-control study.


METHODS
Thirty-nine eyes of 39 patients with PDR and 16 eyes of 16 non-PDR patients (control group) that underwent primary vitrectomy for complications of PDR and other conditions (control group), with a follow-up time > or = 12 months.


METHODS
Proliferative diabetic retinopathy patients were classified into 3 groups according to the extent of fibrovascular proliferation: (1) no or focal adhesions at < or =3 sites (n = 17); (2) > or =1 broad adhesions or vitreous-retinal adhesions around disc, macula, and arcade (n = 12); and (3) vitreous-retinal attachment extending to the periphery or no posterior vitreous detachment with or without retinal detachment (RD) (n = 10). The control group (n = 16) contained non-PDR patients. Vitreous samples were obtained during measurement of vitrectomy and vitreous levels of ROS by luminol-enhanced chemiluminescence assay.


METHODS
Reactive oxygen species levels were recorded as mean (+/- standard deviation) chemiluminescence counts per 10 seconds. Correlations of vitreous levels of ROS among the 3 PDR groups and anatomic prognosis were evaluated. Multiple linear regression analysis of selective potential risk factors was performed to investigate the main determinants of ROS levels.


RESULTS
Vitreous ROS levels were significantly higher in patients with PDR (125.76+/-351.72 chemiluminescence counts per 10 seconds) than in control patients (0.37+/-0.72 chemiluminescence counts per 10 seconds; P<0.0001). Reactive oxygen species levels were 1.86+/-1.63 (group 1), 24.47+/-22.68 (group 2), and 457.94+/-597.01 (group 3); the difference among groups was significant (P = 0.001). Regression analysis indicated that only patient grouping (according to the severity of fibrovascular proliferation) had a strong dependent association with ROS levels (P = 0.001). Final anatomic results revealed that recurrent untreatable RD occurred in 3 patients of group 3, who also had the highest ROS levels.


CONCLUSIONS
Reactive oxygen species levels were significantly elevated in the vitreous fluid of PDR patients, and patients with a more advanced clinical PDR appearance had higher ROS levels. These findings suggest an association between ROS and the pathogenesis of PDR. Reactive oxygen species might be correlated with PDR severity.
Yeh
Po-Ting
PT
Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan.
Yang
Chung-May
CM
Huang
Jen-Shang
JS
Chien
Chiang-Ting
CT
Yang
Chang-Hao
CH
Chiang
Yi-Hui
YH
Shih
Yung-Feng
YF
D000368:Aged; D016022:Case-Control Studies; D003930:Diabetic Retinopathy / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery; D018450:Disease Progression; D005260:Female; D006801:Humans; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014821:Vitrectomy; D014822:Vitreous Body / Q000378:metabolism*
D017382:Reactive Oxygen Species