The occipital lobes form the rear ends of the two major halves of the brain - the cerebral hemispheres. They are principally concerned with our ability to see and interpret what we see.
A discreet hypodensity is what someone studying a computerised tomographic (CT) scan of the brain might observe in a patient. It refers to a small, well-defined area in the brain that is less dense in appearance than the surrounding tissue. The causes are many and can vary from damage produced by a lack of blood supply to that part of the brain to a lump in the brain. Treatment will depend on the cause of the abnormality.
Such an abnormality should be evaluated by a consultant neurologist or neurosurgeon. You are advised to seek such help and guidance.