Fundus vascular occlusion may be due to vascular inflammation, altered blood flow status, vasospasm, embolic detachment and other factors. 1. Vascular inflammation: Usually, the presence of vascular inflammation in patients will lead to inflammatory cell infiltration of the blood vessel wall and perivascular area, which may be accompanied by degeneration of collagen fibers, necrosis of myocytes, fibrin deposition, etc., which may lead to thrombus formation and fundus vascular occlusion. 2. Alteration of blood flow status: slowing down of blood flow and vortex of blood flow are favorable to thrombus formation, which can also induce fundus vascular occlusion. 3. Vasospasm: If the patient’s vasoconstriction is unstable, but there is no organic lesion, resulting in vasospasm contraction, it can also cause fundus vascular occlusion. 4. Embolism: when the embolus formed in other parts of the body of the patient’s blood vessels fall off, it can form tiny embolus, and can also be transferred to the fundus blood vessels with the blood, which can also induce fundus blood vessel occlusion. It is recommended that patients with fundus arteriosus blockage should seek timely medical examination to find out the cause of the disease, and under the guidance of the doctor to carry out targeted treatment, so as to avoid delaying the condition.