Category Archives: Control Devices

Accura: 8DOF Accurately Steerable Platform

As of today, Chronic Total Occlusions (CTO) represent the most technically challenging lesions interventionists face during Percutaneous Coronary Interventions (PCI), with considerably lower success rates (50-90%) in comparison to semi-occluded and acutely occluded arteries [1]. The main technical challenge in PCI of CTOs lies in successfully puncturing and crossing the CTO with a guidewire.

In this section we will focus on crossing challenges. For solutions to puncture the CTO, see the Pulze Hammer I, Pulze Hammer II (coming soon), Cradle Catheter (coming soon), and Wave Catheter (coming soon).

Crossing is challenging as the guidewire cannot be actively steered and deflection can thus not be compensated. This can lead, amongst others, to dissection of the blood vessel wall or subintimal crossing, in which the guidewire crosses the CTO via the blood vessel wall (between the intima and adventitia). Furthermore, it is often challenging to navigate through tortuous CTOs.

A steerable crossing device could be the solution to current crossing challenges, as it will give the interventionist the freedom to actively navigate through the vascular system and CTO freely. Therefore, a steerable prototype nicknamed the Accura was designed with an 8 Degrees Of Freedom (DOF) cable actuated tip (Ø 2 mm, L = 32 mm) divided over 4 steering segments; allowing for constructing complex S-curves. The tip contains a lumen (Ø 1 mm) to allow for the insertion of, amongst others, a balloon catheter, a guidewire, or an IntraVascular UltraSound probe (for visualization purposes). The steerable tip is connected to a rigid shaft (Ø 2 mm, L = 200 mm), which in turn is connected to the handle. The handle consists of an innovative combined locking and steering mechanism to lock the tip position in place and to precisely steer each segment separately. This construction allows for both the tip position and direction to be changed independently, allowing for a scanning movement.

The multisteerable tip has been successfully combined with a single element forward-looking IVUS transducer and Optical Shape Sensing (OSS) fiber to reconstruct a wire frame in front of the tip. This combination will allow for reconstructing and scanning a 3D volume in front of the tip, which can be used to determine the most suitable entry location. Furthermore, the addition of the OSS fiber can potentially minimize the use of X-Ray and contrast fluid during the intervention.

Even though it is still a long way towards a fully applicable clinical tool, the tests have given first insights into the possibilities and advantages of having such a tool in PCI. Currently, a multisteerable catheter is under development.


  • Sakes A., Ali A., Janjic, J., and Breedveld P. (2018). Novel Miniature Tip Design for Enhancing Dexterity in Minimally Invasive Surgery. Journal of Medical Devices. Accepted.


Endo-PaC – Endoscopic Path Controller

Developed in 2011-2012.

In the field of minimally invasive surgery and specifically in pathway surgery – i.e. minimally invasive procedures carried out transluminally or through instrument-created pathways – spatial disorientation is a common experience to surgeons.

Our Endo-PaC (Endoscopic Path Controller) is a simulator designed to investigate human control behavior during path following tasks. Emulating the shaft and handle of a maneuverable surgical instrument, Endo-PaC’s hardware controller consists of a base, an instrument shaft, and a handle with a joystick. The hardware controller contains five position sensors to measure the orientation of the shaft relative to the base, the translational displacement of the shaft, and the orientation of the joystick relative to the shaft. Instead of having a separate joystick, the handle can also be directly connected to the joystick, making the Endo-PaC suitable for comparing thumb control with wrist control.

The hardware controller is combined with custom-developed software animating surgical pathway scenarios. This virtual environment enables the assessment of the user performances based on criteria such as task completion time, motion smoothness, collisions, and the length of the travelled path. This makes the Endo-PaC highly suitable for comparing different control techniques.