An evaluation of the Physical Properties of Current Microcatheters and Guidewires. The Development of the "Catheter-glide Approach" in Response to Weaknesses of Current Materials.

SUMMARY: The physical properties of the 16 microcatheters and 7 guidewires currently available were evaluated to assess their manoeuvrability. This investigation included the latest varieties of these products. The test results showed that there was a wide variation in flexibility and friction between the distal segments of the catheters. Even the recently developed hydrophilic polymer-coated catheters show this variation. Comparisons between guidewires also showed differing degrees of flexibility and friction. Torque transmission was also a variable factor. A combination of the most flexible microcatheter with the lowest friction and the most responsive guidewire with the lowest friction was picked for clinical evaluation. The effectiveness and safety of this combination of equipment was proved by embolising various cerebral arteriovenous malformations( AVMs) and thrombolysing cerebral emboli of arteriosclerotic patients. However it remains difficult to reach the nidus of distally located AVMs with extremely long and tortuous feeding pedicles such as parietal lobe AVMs. The efforts to overcome the weaknesses of current materials by further improving equipment and technique is another subject of the current paper.