Lasers & Catheter Technologies

Lasers, which offer high speeds, incredible precision, and the ability to process without thermally altering the surrounding material, are ideal for removing material through ablation or drilling a variety of micron-sized features in catheter tubing and other materials. As medical catheters become smaller and more complex, lasers are often the only manufacturing technology capable of delivering the necessary accuracy.

Common laser processing applications for medical catheters include:

• Outer diameter reduction—laser ablation removes material from the exterior of the catheter in sub-micron-thick layers, one layer at a time. This technique works well at both macro and micro scales for a wide variety of medical products, including neurovascular, cardiovascular, and other minimally invasive products.
• Laser-cut features—lasers remove material to create access ports for components within the catheter, or to selectively expose functional parts. Lasers drill through one layer of the catheter structure at a time to create micro holes or other geometric shapes to specific depths. Laser cutting is preferred for tiny features in infusion catheters, balloon catheters, and embolic protection filters.
• Surface finish—lasers are used to create high-precision, micro-sized features or patterns on catheter surfaces to enhance performance and functionality. A rougher surface can be beneficial when bonding or welding parts together because it increases bond strength. A textured or patterned surface can also help manage surface tension when moving components are in contact or slide along the same plane or surface.

Catheters are increasingly complex in their designs. Medical device companies seek to add more functionality in less space—for example, multi-durometer or multi-material designs, multi-lumen extrusions with complex profiles and mechanical properties, and inner and outer diameters that continue to get smaller, with thinner walls. As catheter complexity increases, so does the range of medical applications for laser processing. These applications include: 

• Parylene and/or polyimide coating removal for catheters
• Cutting catheters to length
• Micro holes and portals for wire routing in surgical instruments and cardiovascular delivery catheters
• Hole drilling for peripheral vascular drug delivery catheters
• Marking rings, distance indicators, and texts/logos on catheter parts
• Preparing surfaces for welding or assembly

The type of laser selected and the process (laser cut, drill, ablation) depends largely on the features being created and the catheter material selected. For example:

• Laser ablation is frequently used to reduce the OD of the catheter tube or expose satellite lumens inside the catheter so wire leads can be inserted into the lumens and attached to the electrodes.
• Ultrafast lasers are often used for catheters that are made from sensitive materials to further reduce risk of damage or heat-affected zones that might alter performance or durability.
• Laser-cut hypotubes or spiral tubes enhance catheter functionality in several ways, including customizing stiffness and flexibility, kink resistance, torque transfer, and maintaining ovality during a surgical procedure.

Laser processing applications will continue to advance as medical device manufacturers incorporate more complex designs, materials, and added functionality. Often the best solutions result from collaboration between customer and supplier engineering teams to create proprietary laser systems that push the technical limits of laser micromachining and make extraordinary designs a reality.