Related Experiment Video
Updated: Jan 26, 2026

Optimization of the Retinal Vein Occlusion Mouse Model to Limit Variability
Published on: August 6, 2021
Intravitreal dexamethasone implant for central retinal vein occlusion without macular edema
Eun Young Choi1, Hyun Goo Kang1, Sung Chul Lee2
1Department of Ophthalmology, Gangnam Severance Hospital, Yonsei University College of Medicine, 211, Eonjuro, Gangnam-gu, Seoul, 06273, South Korea.
Background:
To evaluate the efficacy of an intravitreal dexamethasone (IVD) implant (Ozurdex®) for the treatment of central retinal vein occlusion (CRVO) without macular edema (ME).
Methods:
A retrospective cohort study was designed, and 20 eyes of 20 patients diagnosed with non-ischemic CRVO without ME were included. A total of 10 CRVO eyes were observed without treatment, and another 10 CRVO eyes received a single IVD injection at baseline. Mean changes in pathomorphologic parameters of fundus and optical coherence tomography parameters were measured at baseline and at 1, 3, 6, and 12 months.
Results:
The decreases in venous tortuosity (p = 0.014 for superior; 0.036 for inferior arcades) and width (p = 0.024 for superior; 0.003 for inferior arcades) from baseline to 12 months after injection were significantly greater in the treated group than the observed group. The improvements in RNFL swelling (p = 0.010) and retinal hemorrhage (p = 0.006) were also significantly greater in the treated group. Visual symptom improvement was significantly faster in the treated group (p = 0.001). In two cases, IVD injection resulted in complete resolution of cilioretinal artery occlusion associated with the CRVO, leading to complete visual recovery in 1 week. None of the treated eyes showed signs of ME development, ischemia progression, or neovascularization.
Conclusions:
IVD implant was significantly effective in improving venous engorgement, retinal hemorrhage, RNFL swelling, and visual symptoms by presumed alleviation of disc swelling and venous outflow. This treatment may be a considerable treatment option in CRVO patients with no ME.
Related Concept Videos
The Central Dogma
The Central Dogma
RNA is the Missing Link Between DNA and Proteins
In the early 1900s, scientists discovered that DNA stores all the information needed for cellular functions and that proteins perform most of these functions. However, the mechanisms of converting genetic information into functional proteins remained unknown for many years. Initially, it was believed that a single gene is...
Measures of Central Tendency
Veins
Structure of Veins:
The structure of veins is specifically designed to assist in the low-pressure transportation of...
Trait Centrality
What is Central Tendency?
The central tendency is the most conventionally used data characteristic. It is a...

