Related Experiment Video
Updated: Jul 7, 2026
An Ex Vivo Tissue Culture Model for Fibrovascular Complications in Proliferative Diabetic Retinopathy
Published on: January 25, 2019
The Effects of Pars Plana Vitrectomy and Panretinal Laser Photocoagulation on Ocular Blood Flow in Proliferative
Mehmet Barış Üçer1, Zeliha Yazar2, Mehmet Önen2
1Department of Ophthalmology, Sincan Training and Research Hospital, Ankara, Turkey.
Purpose:
To evaluate the effects of pars plana vitrectomy (PPV) versus panretinal photocoagulation (PRP) on ocular blood flow in patients with proliferative diabetic retinopathy (PDR).
Methods:
The blood flow parameters of the ophthalmic artery (OA), central retinal artery (CRA), central retinal vein (CRV), and posterior ciliary artery (PCA) of patients with PDR were evaluated with color Doppler ultrasonography (CDU), before and 6 months after PPV and PRP in 24 eyes of 24 patients. PRP alone was applied in the laser group, whereas PPV and PRP were applied to patients in the vitrectomy group.
Results:
CRA's peak systolic velocity, end-diastolic velocity, and CRV's mean velocity were significantly lower after PRP (P = 0.003, P = 0.003, and P = 0.050, respectively). A significant reduction in the resistivity index of CRA (P = 0.005) and OA (P = 0.013) was found in the vitrectomy group after PPV. Despite the application of PRP in the vitrectomy group, the decrease in postoperative flow velocities of the CRA, CRV, and PCA were lower than in the laser group.
Conclusions:
PRP treatment was associated with reduced flow velocities in the CRA and CRV; however, no comparable decline was observed when PPV was combined with PRP. Our findings suggest that PPV may counteract the flow-reducing effects of PRP by enhancing ocular blood flow velocities and decreasing vascular resistance. Given the limited sample size, this investigation should be considered a preliminary pilot study without definitive clinical conclusions.
