Abstract
Purpose :
To investigate the extent and location of nonperfusion area (NP) associated with changes of aqueous cytokines in patients with macular edema (ME) secondary to retinal vein occlusion (RVO) to analyze their association with best corrected visual acuity (BCVA) and central macular thickness (CMT).
Methods :
This prospective study included 31 patients with ME secondary to RVO and 10 age-matched control subjects. Ang-1, Ang-2, MCP-1, IL-8, IL-6, PDGF-AA, PlGF, and VEGF-A levels in the aqueous humor were measured before intravitreal injection or cataract surgery using suspension array technology. Baseline ultra-widefield fluorescein angiography was used to quantify NP and ischemic index (ISI) defined as a ratio of NP to total retina with stereographic projection method to correct peripheral distortion. To assess the amount and severity of NP in different areas, concentric rings centered on the fovea were defined as five zones: peri-macular area (PMA, 0.5-3 mm radius), near-peripheral area (NPA, 3-10 mm), mid-peripheral area (MPA, 10-15 mm), far-peripheral area (FPA, 15 mm-normal perfusion boundary), and the peripheral normal avascular area. The levels of aqueous cytokines between RVO group and control group were compared. And the association between complete/partial NP and ISI from the various rings/zones and BCVA, CMT, and cytokines were evaluated in RVO group.
Results :
The aqueous levels of Ang-1, Ang-2, MCP-1, IL-8, IL-6, PlGF, and VEGF-A were significantly higher in RVO group than control group. The distribution of NP and ISI showed significant difference among the retinal zones (P<0.001). And most extensive NP zone was MPA. MPA with partial ischemia showed significant correlation with CMT, Ang-1, Ang-2, MCP-1, IL-8, IL-6, PlGF and VEGF-A. However, complete NP and ISI did not showed correlation with any other factors. The CMT correlated with Ang-2, IL-8 and baseline BCVA (P=0.016, P=0.021, P<0.001, respectively).
Conclusions :
Angiogenic and inflammatory cytokines in aqueous were overexpressed in RVO patients and showed a distinct difference according to the location and extent of NP. Increased levels of angiogenic cytokines were associated with NP in the posterior and mid-peripheral area with partial ischemia, not with complete ischemia.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.