Twelve-month outcomes in patients with retinal vein occlusion treated with low-frequency intravitreal ranibizumab

Yoshihito Sakanishi, Ami Lee, Ayumi Usui-Ouchi, Rei Ito, Nobuyuki Ebihara Department of Ophthalmology, Juntendo University Urayasu Hospital, Urayasu City, Chiba, Japan Purpose: The purpose of this study was to determine the clinical efficacy of low-frequency intravitreal ranibizumab to treat macular edema due to retinal vein occlusion (RVO).Patients and methods: This was a retrospective examination of cases that received intravitreal ranibizumab for untreated RVO over a period of 12 months. Instead of the conventional three monthly injections, injections were given once during the introductory period. If the recurrence of macular edema was diagnosed during the monthly visit, additional injections were given as needed. There were 21 eyes of 21 patients with branch RVO (BRVO) and ten eyes of ten patients with central RVO (CRVO). The parameters examined included the number of injections over the 12-month period, improvements in best-corrected visual acuity (BCVA), and the central macular thickness (CMT). For BRVO, preinjection parameters that had an effect on the prognosis of BCVA after the 12-month period were also examined.Results: The total mean number of injections over the 12-month period was 3.4 for CRVO and 2.1 for BRVO. For CRVO, the BCVA in log minimum angular resolution changed from a preinjection value of 0.80 to 0.55 at 12 months. For BRVO, the change was from 0.51 to 0.30. For all diseases, BCVA improved after 12 months compared with the preinjection values (P<0.05). There was improvement in the CMT, and the CRVO changed from 765.0 µm at preinjection to 253.5 µm 12 months later. BRVO changed from 524.1 to 250.1 µm, and preinjection BCVA was associated with a prognosis of visual acuity after 12 months of the initial injection (P=0.0485).Conclusion: Even with a low number of injections during the introductory period, there were still improvements in both visual acuity and CMT in RVO patients after 12 months, indicating that it was an effective treatment. Keywords: retinal vein occlusion, IVR, macular edema, BRVO, CRV

Significance of radical oxygen production in sorus development and zoospore germination in Saccharina japonica (Phaeophyceae)

We investigated production of radical oxygen species (ROS) in sorus development of sporophyte discs and during zoospore germination of Saccharina japonica (Phaeophyceae) using the fluorescent dye 2',7'-dichlorofluorescein diacetate (DCFH-DA). Quantitative analysis of ROS showed high intracellular production during the stages of zoosporangium formation when paraphyses elongated. In this stage, remarkable ROS release was observed. ROS production was also observed histologically (under a fluorescence microscope) in the elongating paraphyses and the sorus zoosporangia of the sorus. The sorus had significantly higher phenol content, anti-oxidant capacity and ROS scavenging enzyme activities (ascorbate peroxidase, catalase, glutathione reductase and superoxide dismutase) than adjacent non-sorus blade sectors. Thus, intracellular ROS scavenging mechanisms are active during ROS production in sorus formation. In contrast, iodine content was lower in the sorus than in the adjacent non-sorus tissues, suggesting the existence of an anti-oxidant defense mechanism based on iodine efflux. We demonstrated that ROS production is an important phenomenon in the reproduction of the sporophyte in S. japonica. Furthermore, ROS were also observed in the zoospore germination processes. We discuss the physiological and ecological roles of ROS production in sorus formation and zoospore germination