In the case of leukemia, the cancer interferes with the body's ability to make blood. Leukemia attacks the bone marrow and the blood itself, causing fatigue, anemia, weakness, and bone pain. It is diagnosed with a blood test in which specific types of blood cells are counted.amples of blood from a healthy person and from one with leukemia, a type of blood cancer. Leukemia is often diagnosed after blood testing. Hematologists analyze blood cancer samples. Swollen lymph nodes are one symptom of lymphoma. Red blood cells.
1 Antidepressants, which change how information is processed in the nerves in the brain. Any medication that affects neurological function can affect vision and cause changes in the cornea, optic nerve, lens, macula and retina.  Venlafaxine, prescribed for depression can lead to optic nerve damage and/or glaucoma.
The optic nerve carries images of what the eye sees to the brain. When this nerve become swollen or inflamed, it is called optic neuritis. It may cause sudden, reduced vision in the affected eye. The exact cause of optic neuritis is unknown. The optic nerve carries visual information from your eye to the brain. The nerve can swell when it becomes suddenly inflamed. The swelling can damage nerve fibers. This can cause short or long-term loss of vision.