Leukemia in her central nervous system

This morning the doctors let us know that her leukemia has spread to her central nervous system. I have searched and searched online for an answer while we wait to see her doctor on Monday. This is all I could find:

Leukemia cells occasionally will circulate into the spinal column in the fluid called cerebrospinal fluid (CSF). For them to cause paralysis would be EXTREMELY RARE. See, leukemia cells are blood cells and don't form a 'lump' to compress the spinal column. Solid tumors such as breast, lung, or prostate cancer can spread to the spine and cause paralysis.
Typically, if the leukemia in the spinal column isn't treated the symptoms are usually visual (blurred vision, loss of vision,etc.) or nausea/vomiting.
Treatment of the spinal column usually involves having a special catheter put in place (Omaya reservoir) so chemotherapy (methotrexate or cytarbine) can be injected directly into the CSF.
This is usually done in addition to treating the leukemia throughout the body with systemic chemotherapy

It's not to go on and we have yet to know the full impact until we speak to the doctor. The rounds doctors asked if we had any questions, but luck with them is like playing craps at a casino. We do know that something like 2x a week she has a spinal tap and chemo is injected in and a screening of the fluid is performed. While doing this they basically look to make sure she is clear 4x in a row before they quit checking for it.