All posts by Jette Bloemberg

Plant root inspired steerable needle for urology (CLOSED)

This graduation assignment focuses on the design of a steerable needle for urology procedures, in specific prostate cancer treatment, with a focus on improving accuracy, precision, and patient comfort. The design of the needle will be inspired by the root system of plants, particularly how they extend and move through soil. The tip of the needle will have an extension that can be steered to the desired location within the prostate. 

The assignment involves designing, developing, and testing a novel steerable needle that allows for accurate needle positioning. We are looking for a student who is interested in a design-oriented project and who can start at short notice (i.e., spring or summer 2023). For this project, creative problem solving, SolidWorks, and 3D-printing skills, and an interest in medical topics would be useful. 

Interested? Please contact Jette Bloemberg,, and/or Esther de Kater,

Ovipositor MRI-Needle

Developed in 2020-2021, diameter 0.8 mm.

Female parasitic wasps pass their eggs through an organ called the ovipositor into their hosts, which sometimes hide in a solid substrate such as wood. The ovipositor has the shape of a tube and consists of three slender, parallel-positioned segments, called valves. The wasp can push and pull the valves with respect to each other in a reciprocating manner. A groove-and-tongue mechanism interlocks the valves along their length. The push-pull motion of the valves has two functions. First, it keeps the unsupported length of the individual valves low. Second, moving the individual valves forward one by one while pulling the others provides stability to the wasp’s ovipositor and prevents buckling. The push and pull forces produce a net force near zero, enabling a self-propelled motion.

Inspired by the wasp ovipositor, we developed a self-propelled Ovipositor MRI-Needle with a diameter of 0.8 mm that can be used inside an MRI system. Our needle consists of six parallel needle segments and an actuation unit. The design of the actuation unit is based on the so-called click-pen mechanism of a ballpoint pen. The actuation unit allows you to actuate the needle that consists of six parallel Nitinol segments by just a translating motion. We 3D-printed the components of this actuation to be able to test it inside an MRI system. The video below shows the movement of the needle segments actuated by the actuation unit:

The prototype was tested with success in ex-vivo human prostate tissue in a preclinical 7-Tesla MRI system at the Amsterdam University Medical Centres. The results showed that the needle tip was visible in MR images and that the needle was able to self-propel through tissue.

This project, in which we developed a self-propelled wasp-inspired needle that can be used inside an MRI system, is part of Project 4 of the MEDPHOT programme funded by the Netherlands Organization for Scientific Research (NWO). MEDPHOT focusses on the development of photonics-based technologies that can enable earlier diagnosis and tailored treatment of diseases in the pulmonology, urology, and gastroenterology fields and translate these technologies to their clinical environments. The goal of Project 4 is to develop a novel transperineal laser ablation platform for an accurate treatment of prostate tumours under MRI.


Design of an Octopus-Inspired Device for Stable Needle Insertion (CLOSED)

Octopuses have eight arms that are perfect for gripping rocks, catching prey, and walking along different surfaces. They do this with the suction cups that underline their arms. We are currently developing soft suction cups for stable needle insertion in flexible tissue inspired by these octopus suction cups.

Tissue motion and deformation leads to needle positioning errors. Hence, clinicians typically needle multiple attempts to position the needle at the target location. To achieve accurate needle positioning, clinicians can stabilize the tissue by gripping it. However, gripping and handling of slippery and flexible tissues during minimally invasive surgery is often challenging. Current grippers commonly use a force grip to manipulate tissue, which makes it prone to damage. Octopus-inspired suction cups integrated with a needle could be the solution that stabilizes tissue during needle insertion without damaging the tissue.

This MSc-graduation project involves designing, developing, and testing a novel stable-needle insertion device that allows for accurate needle positioning. We are searching for a student that is interested in a design-oriented project. For this project, SolidWorks, 3D-printing, and creative-problem-solving skills are useful.

Interested? Please contact Vera Kortman ( or Jette Bloemberg (

Design of a Wasp-Inspired Steerable Needle for Urology (CLOSED)

In nature, there is a special group of wasps known as parasitoid wasps. They have a thin and steerable needle-like structure called the ovipositor. This ovipositor is used to lay eggs in hosts. The ovipositor is a very thin organ shaped like a flexible, hollow needle. In order to reach the right location, the wasp can steer her ovipositor. How it steers is still being studied.

We are currently developing novel steerable needles for prostate and kidney interventions inspired by the wasp ovipositor. This project will focus on understanding the steering mechanism of the ovipositor and applying this to new needle designs. We are searching for an MSc student that can start at short notice with this interesting graduation project.

Interested? Please contact Jette Bloemberg,

Design of an Ultrasound-Enhanced Needle (Closed)

Needles are an integral part of many medical procedures nowadays. In prostate cancer ablation procedures, for example, surgeons insert a needle into the prostate tumor with image guidance to deliver the treatment fiber to the cancerous tissue. Needle insertion is not, however, a simple task and requires precision localization to reach the target accurately. Furthermore, minimal insertion forces are required to preserve the tissue that the needle is penetrating. In nature, some wasp and mosquito species are able to move a needle-like structure in substrates using a vibrating motion, this vibrating motion is thought to reduce the frictional force during the penetration process. In this graduation project, we look forward to developing an ultrasound-enhanced needle to minimize the effect of the friction forces acting on the needle, thus increasing the positioning accuracy and minimizing the tissue damage due to penetration.

The assignment is available from October 2021. Interested? Contact Jette Bloemberg: or Mostafa Atalla:

NWO MEDPHOT – MRI-ready steerable needles

This research project is part of the MEDPHOT programme and is funded by the Netherlands Organization for Scientific Research NWO. The MEDPHOT programme, carried out bij a consortium of Dutch Universities, university medical centres, and companies, aims to develop new optical biomarkers that are needed to realise earlier diagnosis, improved treatment and better quality of life in the fields of oncology, asthma, and neurodegeneration.

The standard surgical treatment of prostate cancer is radical prostatectomy. However, side effects of radical prostatectomy are incontinence and erectile dysfunction. A local treatment that preserves noncancerous tissue like focal laser ablation reduces these side effects. Focal laser ablation is an optical fibre-based laser ablation treatment that allows for fast percutaneous focal ablation of prostate tumours. Using needles and magnetic resonance imaging (MRI)-guidance, the medical operator can position optical fibres at the target region. However, for ablation to be successful, it is important to have full positioning control over the accuracy and extend of the ablation.

This research aims to develop an MRI in-bore ready steerable needles to position the optical treatment fibre at the target region. A novel actuation system will allow for safe use inside the MRI scanner.  The integration of the steerable needle, the novel actuation system, and a laser ablation fibre will make the needle suitable for use under MRI guidance to enable precise ablation of the prostate tumour.