Abstract
Purpose: :
To assess components of the fibrinolytic system in the vitreous humor and serum of patients with vitreoretinal disorders undergoing pars plana vitrectomy.
Methods: :
43 samples of vitreous humor and plasma of 43 patients undergoing vitrectomy for macular hole, macular pucker, retinal detachment or proliferative vitreoretinopathy (PVR) were evaluated for their content of plasminogen, a2–antiplasmin, plasminogenactivator–inhibitor 1 (PAI–1), plasmin–a2–antiplasmin–complex (PAP), tissue plasminogen activator (t–pa), total protein, albumin, d–dimer. Patients were divided into 4 groups according to their diagnosis and the groups were compared to each other.
Results: :
Of the 43 patients 25 (58%) were male, the mean age was 65 years. 8 patients (19%) underwent vitrectomy for macular hole, 12 patients (28%) for macular pucker, 11 patients (25%) for retinal detachment and 12 patients (28%) for PVR. Plasma levels of plasminogen (64.73, 64.25% of norm vs. 108.94, 116.03% of norm, p<0.001), a2–antiplasmin (54.86, 61.36% of norm vs. 105.5, 80.36% of norm, p<0.001) and PAI–1 (42.08, 36.69ng/ml vs. 65.22, 65.35ng/ml, p<0.05) were elevated in the groups of retinal detachment and PVR compared to macular hole and macular pucker groups. Plasminogen levels in the vitreous were below the detection level of 10% of norm. Patients with macular hole had the lowest vitreal concentration of each measured factor. The groups of retinal detachment and PVR had elevated vitreal levels of PAI–1 (352.52, 370.73ng/ml vs. 1.86, 56.64ng/ml, p=non significant), PAP (2416.50, 1836.24µg/l vs. 124.21, 133.35µg/l, p<0.001), albumin (0.12, 0.23g/dl vs. 0.03, 0.07g/dl, p<0.05) and d–dimer (4.76, 1.64µg/ml vs. 0.40, 0.48µg/ml, p=non significant) when compared to patients with macular hole and macular pucker.
Conclusions: :
There are significant differences in the vitreal concentration of components of the fibrinolytic system in patients with vitreoretinal disorders. Breakdown of the blood–retinal barrier seems to be contributing to an accumulation of components of the fibrinolytic system in the vitreous.
Keywords: vitreous • vitreoretinal surgery • retina