Abstract: Provided is, among other things, a method of treating in an animal infection or neoplasm of cerebrospinal tissue characterized by a risk of death, the method comprising: (a) injecting a physiologically acceptable fluid for cerebrospinal perfusion into a first catheter into the cerebrospinal pathway, which fluid for cerebrospinal perfusion has an therapeutically effective amount an agent, the agent selected for effectiveness against the infection as identified or diagnosed; (b) withdrawing fluid at a second catheter into the cerebrospinal pathway to create a flow and flow pathway between the first and second catheters; and (c) maintaining the flow for a period of time adapted to perfuse at least 1 CSF volume.

Abstract: Subarachnoid hemorrhage is treated by circulating a synthetic cerebrospinal fluid containing an emulsifying agent in the cerebrospinal fluid pathway in the vicinity of hemorrhage. The emulsifying agent scavenges blood products and circulation of the synthetic cerebrospinal fluid clears the blood products form the subarachnoid space to reduce cerebral vasospasm.

Abstract: Provided is, among other things, a method of treating in an animal infection or neoplasm of cerebrospinal tissue characterized by a risk of death, the method comprising: (a) injecting a physiologically acceptable fluid for cerebrospinal perfusion into a first catheter into the cerebrospinal pathway, which fluid for cerebrospinal perfusion has an therapeutically effective amount an agent, the agent selected for effectiveness against the infection as identified or diagnosed; (b) withdrawing fluid at a second catheter into the cerebrospinal pathway to create a flow and flow pathway between the first and second catheters; and (c) maintaining the flow for a period of time adapted to perfuse at least 1 CSF volume.

Abstract: Provided is a method of delivering to neurological tissue a transforming composition or a transformed cell, the method comprising: a. injecting a physiologically acceptable cerebrospinal perfusion fluid into a first catheter into the cerebrospinal pathway, which cerebrospinal perfusion fluid has a gene therapy effective amount of gene therapy agent or transformed cells; b. withdrawing fluid at a second catheter into the cerebrospinal pathway to create a flow and flow pathway between the first and second catheters; and c. maintaining the flow for a period of time adapted to perfuse at least 1 CSF volume.

Abstract: Provided is a method of treating in an animal that has suffered damage to cerebrospinal tissue or that has an indication creating a risk of damage to cerebrospinal tissue, the method comprising: a. injecting a physiologically acceptable cerebrospinal perfusion fluid into a first catheter into the cerebrospinal pathway, which cerebrospinal perfusion fluid has a neuroprotecting effective amount of a neuroprotectant; b. withdrawing fluid at a second catheter into the cerebrospinal pathway to create a flow and flow pathway between the first and second catheters; and c. maintaining the flow for a period of time adapted to perfuse an affected tissue.