Clinical Study of High Concentration Ganciclovir Eye Drops in the Treatment of Cytomegalovirus Retinitis

Inclusion Criteria: 1. Patients voluntarily participate in studies and sign informed consent forms 2. Ages 2-80 years (with cut-off values) male and female 3. One of the following is true （1）In patients with cytomegalovirus retinitis after hematopoietic stem cell transplantation/cord blood transplantation, the white blood cell count is less than 4× 10\^9/L, and the platelet count ranges are 25× 10\^9/L≤ PLT\<100×10\^9/L，Intravitreal injection carries a greater risk of infection and bleeding, and is unable to administer systemic medication due to the bone marrow suppression of antiviral drugs, or systemic medication for severe CMV retinitis cannot be well controlled; （2）In patients with CMVR with AIDS, the CD4+ T cell count is less than 100/μl, there is a great risk of infection with intravitreal injection, and the systemic medication of severe CMV retinitis cannot be well controlled. Exclusion Criteria: * Eye condition 1. The presence of refractive interstitial opacification affects fundus observation; 2. Intravitreal ganciclovir or sodium phosformate injections were performed within 1 week prior to baseline; 3. Other diseases that can affect visual function such as syphilis-related eye diseases, acute retinal necrosis, congenital glaucoma, congenital corneal lesions, congenital macular degeneration, etc. * General condition 1. Severe neutropenia (\<0.5×10\^9) or severe thrombocytopenia (\< 25× 10\^9/L); 2. Other investigators judged patients who were not suitable for enrollment;