What are the key questions to be asked at the start of the catheter design process to help accelerate your product to market?
Bringing a catheter or any medical device from design through to scale manufacturing can be a challenging journey. It is a journey fraught with many potential pitfalls and hurdles to be avoided, but also many opportunities that must be grasped and taken advantage of.
At ICS Medical Devices it is a journey that we have made alongside our customers many times. Our role is to act as your guide, as an extension of your team, to see the pitfalls before they become problems, and to spot the opportunities that can work to our advantage.
Our experienced engineers do this by asking probing questions at every step, always with the clinical end use and manufacturability in mind, to help your device development life cycle to be smooth and efficient.
Design for manufacture is a key consideration in our design process, decision making, and design selection process. That could be how to improve the design to optimise the process or it could be choosing the best supply chain options for your product.
What sort of questions do we ask? Well, have a look at our video of a catheter device construction process and consider the following as you do:
What catheter shaft construction do you require?
- Do you require a thermoplastic liner for workhorse shafts or low friction PTFE materials for implant delivery or telescoping shafts?
- Do you require a sealed liner for high pressure applications?
- Do you need to carry high pressure through inflation lumens within the wall off the shaft?
- Does your shaft require low profile walls?
- Do you need to optimise your tensile and compression properties in your shaft layup?
What are your shaft properties?
- Flexibility – do you require a flexible highly navigable device for torturous applications?
- Tensile and / or compression properties – shaft structural strength for example in deployment or implants where shafts telescope within each other and other different stresses. Do you need further axial reinforcement to improve tensile and compression strengths?
- Radial force? do you load an implant in your sheath (e.g. a stent for up to 2 year) or pass implant through your shaft which has high radial forces.
- Kink resistance? Does you shaft pass through tight anatomical pathways, does your through lumen need to remain integral at these radii.
- High pressure – burst resistance? Does your shaft or internal lumens in your shaft wall carry high pressure?
- Or perhaps multiple, often competing performances?
- Visual Markers – does your shaft required accurate placement with the use of visual markers?
- Visibility under Radiopacity/Ultrasound – does the device require visualization under Fluoroscopy/Ultrasound? Local area or along the length?
What are your catheter shaft jackets requirements?
- Structure? What are the general requirements and compatibilities required for your shaft?
- Flexibility and stiffness transition control along the shaft – stiffer proximal ends and softer distal ends, low-profile smooth jacket surface with atraumatic features?
- How many transition zones do you require and what level of stiffness transition can you accommodate from one zone to the next? A very relevant consideration in neurovascular applications.
Mechanical Functionality
- Does your shaft need to steer and what articulation do you require? What angles and radius of curvature?
- Do you require single-plane single-way, single plane-two way or multi-plane multi-way steering?
- What are the forces required to deflect your shaft with and/or without an implant in the deflection zone?
- Will it require high-tensile shaft construction, or do you maintain low profile and flexibility?
These questions drive design selection of mechanisms to articulate or actuate and assembly of these mechanisms within the shaft.
High-Performance Assembly
- What forces do you need welds to withstand – e.g. for steering, deployment or other mechanical functionality?
- Can a mechanical method of attachment substitute for a weld to improve safety and performance?
- Design your pull wire and welds and attach mechanisms to meet specifications and build in a safety factor to ensure safe performance in the field.
- What are the requirements for the handle actuation mechanisms, what handle attachment features need to be accommodated into the shaft assembly? What are the forces required? Typically force loads are the highest in the handle and need to be designed carefully.
Other Important Considerations we would address with any prospective design, development and prototyping collaboration:
- What is your catheter shaft intended use? What type of procedure, what anatomy, who operates it, devices / other shafts it works with and its function.
- What type sterilization method will you apply? And are there any specific design or material considerations for that sterilization method?
- Where is your price point for the assembly? Do you have design vs cost trade-offs? Have you applied value engineering fundamentals to your design specification?
- What scale and volumes do you require over your development and manufacturing lifecycle? This is both a key design and manufacturing variable that should be considered early for the full lifecycle of your product.
As you can see there is a lot to consider, which is why it helps to work alongside a partner who is experienced in the catheter design and development process. Our experience and expertise allows us to ask these questions and more, to see the opportunities and challenges at an early stage, and ultimately to save you time and money as we accelerate your product along its development life-cycle.
Contact ICS Medical Devices today to discuss how we can combine our catheter and device expertise with your therapy and clinical expertise to develop an optimum product solution.