abstract |
A filter-catheter consists of outer (2) and inner (3) flexible tubes, e.g. oil PTFE, with the duct between them linked to the filter, which is formed from a series of lengthwise strips (6) separated by slits (5). The proximal end of the catheter has a coupling unit (10) which is linked to the duct between the catheter tube and has a seal (14) through which the inner tube can slide. The filter can be varied by sliding the inner tube of the catheter relative to the outer one, causing the strips (6) to bulge and increase the size of the gaps between them. |