Method of providing an implantation site in soft tissue

A method for forming, with a device, a substantially straight channel filled with aqueous gel in soft tissue, the channel being used for subsequent insertion of structures in the micrometer range such as a thin filament, or an electrode of an optical fiber, the device comprising an oblong, rigid pin comprising a distal section extending from a distal end of the pin towards a proximal end of the pin, a central section extending from the distal section towards the proximal end making up an axial extension, and a proximal section extending from the central section to the proximal end, a central conduit extending from the proximal end to the distal section and closed at its distal end, the distal section having a diameter decreasing towards the distal end forming a sharp or blunt distal end facilitating insertion into the soft tissue, the central conduit providing fluid connection between a reservoir for aqueous gel, the pin in its central section comprising lateral passages extending radially from the central conduit and the lateral passages being distributed over the central section, the channel in the soft tissue that is filled with aqueous gel having a depth corresponding to a length of the pin measured from the distal end of the pin to a proximal end of the central section of the pin, and the distal and proximal sections not having lateral passages extending laterally from the central conduit, the method comprising:

• inserting the device into the soft tissue;
• supplying the aqueous gel outside of the central section via the central conduit and the lateral passages from the reservoir during insertion of the device by way of applying pressure to the aqueous gel to force neural tissue abutting the outer face of the central section away from the pin to form a layer of aqueous gel around the central section;
• and
• withdrawing the device from the tissue while leaving the aqueous gel in the tissue thereby forming the channel filled with the aqueous gel, wherein the gel channel has a configuration enabling the structures to be inserted into the soft tissue without coming in direct contact with the soft tissue.