^
The first component to consider in steerable catheter design does not actually make it into the final product – this component is the processing mandrel. Depending on the design requirements for the inner lumen of the steerable shaft, the following must be considered:
The next component MIS evaluates in the design process is the liner material for the main lumen and pull wire lumens for the catheter. Liners are lubricious material that line the inner diameter of lumens to reduce frictional forces from passing other instruments, catheters, devices, and in the case of steerables, pull wires through these lumens. There are a number of options for liner material to incorporate into the delivery system, and they ultimately depend on the application. Common liner materials typically consist of:
The next layer to a steerable catheter delivery system is either a lamination aid or a reinforcement layer. The reinforcement layer plays a critical role in the overall device torqueability, achievable bend angles and bend diameters, kink resistance, and pushability. Depending on the application of the device, performance requirements, and other interacting devices, MIS engineers have a plethora of options in their catheter reinforcement toolbox, including, but not limited to:
At the distal end of the reinforcement segment of a catheter, it is common to abut a steering assembly. Most commonly this includes a pull ring and pull wire assembly; however, there are other technologies like magnets and coaxial steering mechanisms that can be employed. For the majority of steerable systems, a pull ring and attached pull wire will be employed and act as a critical component which drives the articulation of the overall catheter system. Several items that we consider during pull wire and ring development are:
The final layer in constructing a steerable delivery system is the jacket, or medical extrusion. The extrusions provide coverage over the reinforcement layer of the catheter and are also critical to the device torqueability, flexibility, compression and elongation resistance. MIS will help in developing a number of specifications surrounding these jackets, which include:
Contact us today to discuss how we can help determine the optimal approach to design your articulating catheter, and partnering with you on the development of your delivery system.
Mandrel and processing aid selection is critical in microcatheter design. Depending on the design requirements for the inner lumen of the microcatheter, there are several features that must be considered:
The next component MIS evaluates in the design process is the liner material for the main lumen of the catheter. Liners are lubricious material that line the inner diameter of lumens to reduce frictional forces from passing other instruments, catheters, devices. There are a number of options for liner material to incorporate into the delivery system, and they ultimately depend on the application. Common liner materials typically consist of:
Liner thicknesses for microcatheters can vary, but we have experience in working with liners that have a single wall thickness as low as 0.0005”.
The next layer to a microcatheter delivery system is typically a reinforcement layer. The reinforcement layer plays a critical role in the overall device torquability, achievable bend angles and bend diameters, kink resistance, and pushability. Depending on the application of the device, performance requirements, and other interacting devices, MIS engineers have a plethora of options in their catheter reinforcement toolbox, including, but not limited to:
Braided and coiled hybrid designs are commonplace in microcatheter design. A proximal braided portion provides pushability and torquability, while a coiled distal section allows for a tighter bend radius to be achieved while minimizing lumen ovalization. Important system considerations need to be taken into account, particularly at the junction of the braid and coil segments, and our experienced team can provide guidance in these areas.
The final layer in constructing a microcatheter is the jacket, or medical extrusion. The extrusions provide coverage over the reinforcement layer of the catheter and are also critical to the device torqueability, flexibility, compression and elongation resistance. MIS will help in developing a number of specifications surrounding these jackets, which include:
Contact us today to discuss how we can help determine the optimal approach to design and develop your custom microcatheter.
