Patent ID: 8231586

Claim:
A cerebrospinal fluid (“CSF”) collection tube comprising: a bottom end portion; a tubular sidewall portion with a first end and a second end having an interior surface and an exterior surface, wherein said first end is sealed to said bottom end portion and wherein said second end defines an open end portion; a filament element configured to collect fluid, wherein said filament element includes a first end and a second end; and an attachment element, wherein said attachment element directly attaches said first end of said filament element to said interior surface of said tubular sidewall portion; wherein said filament element is flexible and can move between an extended position in which said filament element projects through said open end portion and a retracted position in which said filament element does not project through said open end portion; and a removable cap sized and configured so as to seal said open end portion wherein said cap causes said filament element to assume a retracted position when said cap is positioned to seal said open end portion..