Patent ID: 7455666

Claim:
A method of navigating a spinal subarachnoid space in a living being, comprising: percutaneously introducing a guidewire in a first direction through an introducer and into the spinal subarachnoid space at an entry location, the guidewire being sufficiently flexible to navigate the spinal subarachnoid space, the introducer having a distal end; advancing the guidewire in a second direction beyond the distal end of the introducer, the second direction being different from the first direction; percutaneously introducing a device over the guidewire and into the spinal subarachnoid space, the device having a first passageway sized to slidably receive, and work with, at least the guidewire, and the guidewire being positioned in the first passageway; advancing the device over the guidewire and within the spinal subarachnoid space at least more than 10 centimeters from the entry location; introducing a penetration apparatus through the first passageway of the device, the penetration apparatus including an outer sleeve element and an inner puncture element, the outer sleeve element and the inner puncture element being slidably coupled together; puncturing the pia matter using the penetration apparatus; and advancing the device over the guidewire from the spinal subarachnoid space into the intracranial subarachnoid space.