Category Archives: General

Beter worden met ‘electroceutica’

Electroceutica kunnen helpen om allerlei aandoeningen, zoals tinnitus (oorsuizen) en epilepsie, te bestrijden. Dat zegt prof. Wouter Serdijn in zijn intreerede als hoogleraar bio-elektronica aan de TU Delft op woensdag 30 maart. Electroceutica betreft het slim, lokaal en gericht toedienen van helende elektrische pulsen aan het lichaam. De technische uitdaging is het slimmer en kleiner maken van de apparatuur.

Minder bijwerkingen

Volgens prof. Wouter Serdijn kunnen ‘electroceutica’ uitgroeien tot een nieuw en belangrijk type medicijn, naast en als aanvulling op de al bestaande farmaceutica. Werken farmaceutica op een chemische wijze in op het lichaam, electroceutica doen dit op een elektrische manier.
Electroceutica dienen helende elektrische pulsen aan het lichaam toe op een slimme en gerichte wijze, vooral voor aandoeningen die hun oorsprong vinden op specifieke plaatsen, in bijvoorbeeld de hersenen.Het gericht geven van elektrische pulsen kan bij veel aandoeningen helpen, en is zeker niet alleen toepasbaar in de hersenen. Het grote voordeel van de elektrische methode boven farmaceutica is dat het effect lokaal is. Pillen werken immers in op het hele lichaam en veroorzaken derhalve snel bijwerkingen.

Slimmer en kleiner

Serdijn ziet electroceutica nadrukkelijk als aanvulling op ‘gewone’ medicijnen. ‘Het gaat om het vinden van de perfecte combinatie  tussen electroceuticals en conventionele medicatie. Op dit moment is het toedienen van elektrische pulsen aan het lichaam nog vrij grofstoffelijk, met bijvoorbeeld relatief grote batterijen en draden. Ook heeft de methode nog een vrij hoge graad van trial and error.’

Een chip in zijn meet-behuizing voor het uitlezen van de neurale signalen tijdens en direct na het elektrisch stimuleren, door Cees-Jeroen Bes, in samenwerking met LUMC-KNO. Ondersteund door STW, TMSi, AB-Sys and HealthTech.

Er zijn daarom twee technische hoofddoelen, zegt Serdijn. ‘De uitdaging is het kleiner (dus ook makkelijker implanteerbaar) én slimmer maken van de apparatuur. Dat slimmere zit hem vooral in het meten van de toestand van en het aanpassen van de therapie aan een individuele patiënt. Dit patiënt-specifieke element is heel belangrijk. Want niet alleen is iedere patiënt anders, de toestand van iedere individuele patiënt varieert ook nog eens in de tijd. Door dit te meten en terug te koppelen kunnen we veel gerichter de juiste therapie instellen.’

Concreet is het doel om een flexibel hersenimplantaat te ontwikkelen op een polymeer-substraat. Dat implantaat dient dan als algemeen platform voor diverse typen implantaten.

Tinnitus

Volgens Serdijn is het (potentiële) toepassingsgebied van electroceutica zeer breed. ‘Het kan bijvoorbeeld worden ingezet voor de behandeling van onder meer tinnitus (oorsuizen), epilepsie, het syndroom van Tourette en bepaalde verslavingen. Op deze gebieden worden nu ook al successen geboekt.’
‘Neem tinnitus als voorbeeld. Wereldwijd hebben meer dan 500 miljoen mensen hier last van. Sommige patiënten kunnen worden geholpen via elektrische pulsen. Nu gebeurt die behandeling nog subjectief’, zegt Serdijn. ‘De patiënt moet zelf aangeven wat hij hoort en of er enige verlichting als gevolg van de stimulatie is opgetreden. Intelligente electroceuticals kunnen de doelmatigheid van de toegepaste therapie continu monitoren en deze aanpassen aan de behoeften van de patiënt, zelfs wanneer deze alweer op de terugweg is van het ziekenhuis.’

Symposium

Uiteraard vinden de technische ontwikkelingen plaats in nauwe samenwerking met artsen. Dit komt ook tot uiting in het symposium dat op de dag van de intreerede van Serdijn wordt gehouden. Medical Delta partners ErasmusMC en LUMC zijn goed vertegenwoordigd in het programma. Tijdens het symposium wordt bio-elektronica besproken vanuit een technologisch, een medisch, een klinisch, een industrieel en een maatschappelijk perspectief. Vijf vooraanstaande sprekers van het ErasmusMC, het LUMC, de Dunedin School of Medicine en een biomedisch bedrijf behandelen deze thema’s.
Meer informatie
Het symposium en de intreerede van prof. Serdijn.
Contact
Wouter Serdijn, prof. bio-elektronica TU Delft, W.A.Serdijn@tudelft.nl, +31 (0)15 278 1715.
Claire Hallewas, persvoorlichter TU Delft, c.r.hallewas@tudelft.nl, +31 (0)6 4095 3085.

Electronics in Neonatology

Bij Rico van Dongen, honorary member of the Bioelectronics Group

An Electronic Fetal Monitor, also known as cardiotocograph (CTG), to record the fetal heartbeat and the uterine contractions during pregnancy

On December first of last year I became the proud father of a baby boy, Wouter. Unfortunately, the pregnancy and birth did not go according to plan and my wife and I were exposed to a long period of hospitalization and a lot of medical devices.

It all started October last year when my wife was hospitalized with pre-eclampsia, a form of pregnancy related high blood pressure. The fact is there is no cure or proper treatment for this besides inducing labor and abort the pregnancy. Being only 25 weeks pregnant at the time the survival changes of the baby are already quite good thanks to modern neonatology, but certainly not without complications.

Obviously the best path for our unborn child was to extend the pregnancy for as long as possible and try to control the high blood pressure with medication. Two months of intensive hospital care and almost weekly increasing dose of medication followed.

The heartbeat of our baby was monitored daily by means of cardiotocography, CTG, to check if he could still handle the high dose of medication. The resulting graphs were, according to the doctors, sub-optimal. This resulted in the fact that my wife was connected to this CTG machine for up to 4 hours a day before the doctors were confident again that our baby was stable.

As a father confident in the strength of our child I soon blamed the machine for this sub-optimal picture. It was not long before we realized that almost all drops in heartbeat correlated with movement of the baby. As an engineer, my hands were itching with the urge to re-write the software of this machine and add an additional graph with signal quality to the output.

Weeks of endless CTG and blood pressure medication passed. By the time of the 30st week of pregnancy oral medication was nog longer sufficient and the real heavy stuff was administered through IV drip. Two weeks passed until there was no other option than to abort the pregnancy.

Although usually inducing labor is not successful at this early terms my wife managed to pull it off and finally our son was born. Although weighing only 1417g it was a strong guy that could already breath on his own. He spent only one night at the intensive care for observation before we could move him to the high-care section.

The good news only lasted half a day. After a routine ultrasound of the brains the doctors discovered a massive hemorrhage. His right ventricle was half filled with blood and the left completely filled. At the left side there was already sign of damage to brain tissue. The damage concentrated to the connections from the motor cortex to the central nerve system. The neonatologist explained to us that bleedings at premature born babies are not that uncommon, the strange thing about our case was that the bleeding already occurred before birth. Luckily the human brain, and especially the undeveloped brain of babies, is capable of finding new connections and avoid damaged regions.

There is a chance that we won’t be able to notice anything abnormal in the way our baby moves but it was clear that our days of worrying and hospital visits were long from over. But first things first, being only 1417g our boy needed to gain strength in an incubator.

The incubator is, again, a collection of medical electronics where the engineer in me would love to make some improvements. Take for example the electrodes used for monitoring the heartbeat and the sensor for measuring blood oxygen saturation. I’m not sure if it was the way of handling our baby but somehow the leads always seemed to be tangled. Small wireless sensors would be very helpful in this situation. Perhaps this is a good use for low power ultra-wide-band technology. On the other hand, it is nice to see the designers already took some effort making the electrodes fit in to the cuddly baby environment by printing cute teddy bear pictures on them.

Another one and a half month passed before out baby boy was strong enough to leave the hospital. As a final check an MRI was made. It clearly showed the damaged regions but also that the brains developed normal and that the remaining blood was gradually cleared away. At this point he is just like any other baby. There is nothing wrong with his ability to cry us awake during the night or to kick off his socks. Nevertheless, his development will be closely monitored with perhaps even more electronics.

I guess my messages to other biomedical engineers is first of all, keep up the good work. Until you need the electronics we design you don’t really realize how valuable our work is. Secondly, I think it would be helpful to try to evaluate the design from the viewpoint of the patients and medical personnel that are using your products.

Rico van Dongen, Febr. 6, 2016

Baby Wouter van Dongen

Baby Wouter van Dongen

Symposium: Bioelectronics meets Electrophysiology, Wednesday, 30 March 2016, 09:30-18:00 hrs, Aula Main Auditorium, Delft University of Technology, Delft

Symposium: Bioelectronics meets Electrophysiology

Wednesday, 30 March 2016

09:30-18:00

Aula Main Auditorium, Delft University of Technology, Delft

Johan Frijns (LUMC), Jeroen Dudink (ErasmusMC), Richard Houben (AB-Sys), Freek Hoebeek (ErasmusMC), Dirk Ridder (Otago Univ.)

On the occasion of Wouter Serdijn’s recent appointment to full professor in bioelectronics and the inaugural ceremony in which he accepts his appointment, a full-day symposium will be organized. This symposium addresses bioelectronics from a technological, a medical, a clinical, an industrial and a societal perspective. Five distinguished speakers from the Erasmus and Leiden Medical Centers, from the Dunedin School of Medicine and from Applied Biomedical Systems will address these challenging topics.

The symposium language will be English and free of charge. Registration is required, though. Please click the following link to register: Registration

Programme:

9:30 hrs: registration and coffee
10:00 hrs: opening of the symposium by the chairman, Dr.ir. Marijn van Dongen
10:10 hrs: Prof.dr.ir. Johan Frijns, Leiden University Medical Center, ENT Cochlear Implants: Clinical problem, technical solution and social impact
10:40 hrs: Dr. Jeroen Dudink, Erasmus Medical Center, Neonatology The future of baby brain monitoring
11:10 hrs: Ing. Richard Houben, Applied Biomedical Systems Electroanatomical Mapping of Persistent Atrial Fibrillation
11:40 hrs: coffee break
12:10 hrs: Dr. Freek Hoebeek, Erasmus Medical Center, Neuroscience Bioelectronics allow the small brain to conquer the big brain
12:40 hrs: Prof.dr. Dirk de Ridder, Dunedin School of Medicine, New Zealand Bioelectronics controls the brain by mimicking nature
13:10 hrs: lunch
15:00 hrs: inaugural ceremony and speech of Dr.ir.Wouter Serdijn, Delft University of Technology Beter worden met elektrceutica: elektronische medicijnen reiken de helpende hand 

(Eng: Getting Better with Electroceuticals: electronic medicine to the rescue)

16:30 hrs reception+

How do you become Best Lecturer of TU Delft?

Nominated best lecturers 2015 – Wouter Serdijn (EEMCS) and Ianus Keller (IDE) – and students give a sneak peek in their way of teaching. After these tips you could become Best Lecturer 2016.

On 26th November, the Best Lecturer of the year 2015 was chosen. 8 nominees, one from each faculty, competed for the prize. But how do you ‘become’ lecturer of the year of lecturer or your faculty? How does the lecturer of the year differentiates him or herself from the other lecturers? Is the interaction with the students different and what is the ‘Golden tip’?

Read more

Intuitive CMOS transistor modeling

On Oct. 6, 2015, I gave a guest lecture in the lecture series “Structured Electronic Design” (EE4C09) on Intuitive CMOS Transistor Modeling. In there I explain the 5 regions of operation of an MOS transistor (both in weak inversion and in strong inversion, both in triode and saturation, and off), based on the EKV model. For those of you that might still be struggling with understanding how the CMOS transistor works and how it can be employed in first time right, first time best analog and mixed signal circuit design, this lecture is for you.
See the complete lecture, which also treats double loop negative feedback amplifiers, herehttps://collegerama.tudelft.nl/Mediasite/Play/d2fc417f2e644a64b4463e34322f86a31d?catalog=528e5b24-a2fc-4def-870e-65bd84b28a8c

Do you really listen or hear?

Learning in the true sense of the word is possible only in that state of attention, in which there is no outer or inner compulsion. Right thinking can come about only when the mind is not enslaved by tradition and memory.”

–  Jiddu Krishnamurti

Considering all the senses we possess, the post could have been named “Do we see or look?” or perhaps  “Do we speak or talk?”. But among the three, I would like to focus more on the capability to hear and listen, which also holds relevance to the research conducted at the bioelectronics group. To provide a sense of appreciation, simply look at how elegantly the brain processes the sounds we hear, with clear distinctions in frequency and amplitude making innumerable nervous connections, to generate a unique experience. For instance, when you hear the far away church bell ringing in a crowded marketplace, it fills you with joy and hope. If you care about the quality of the sound and prefer using high end headphones, you would know the joy of heavy bass sound and clear vocals that you savor while listening to music!

With tremendous advancements in microelectronics, thousands of individuals with varying degrees of disabilities are now able to hear better with the support of hearing aids, where the size of the aid is diminishing rapidly, while maximizing comfort. As an example, the cochlear implants (CI) are being used for the restoration of the hearing ability and is on the road to absolute bliss in audition. As exciting and extreme the research continues to be, I would like to draw your attention to the significance of listening, going beyond hearing, and the differences lying therein.

Although we have managed to bring about considerable improvement in the hearing abilities of the people through scientific progress, have the fully abled beings actually made complete use of the capabilities in a way that would enhance their personalities and their understanding? Do we truly listen?

Difference between hearing and listening

When we hear someone speak, we produce our own formulations and thoughts, we are either accepting or rejecting his/her idea, as the speaker speaks. We stand to compare his words with what we think based on the background, knowledge base and the experience we possess. This very fact is the denial of listening. While hearing is the ability to perceive sound by detection of the changes in pressure in the surrounding medium, which is involuntary, listening is an act you choose to do voluntarily, a decision you take consciously.

In Jiddu Krishnamurti’s words, in listening there is no comparison, neither is there acceptance nor rejection. The quality of listening is your attention. When you listen, every part of your body is in rapt attention to what is being spoken, intensely, where there is no judgement. There is no confusion but absolute clarity. You are neither influenced by the person’s appearance, nor intimidated by his presence. When you do that, you listen to the subject of discussion wholly. You are then in a position to discriminate right from wrong. There is a strong inner urge to understand the speech fundamentally, and not superficially be steered by the speaker and/or being ignorant. You are then very observant of the changes that are taking place within you, subtle nevertheless. A detailed discussion is available here for the interested reader.

Krishnamurti speaks in depth about the state of the mind while listening. A calm mind can perceive and listen with great clarity. Also, such a mind can have positive influence on the environment, the essence of which is well captured in one of Krishnamurti’s commentaries about “The noisy child and the silent mind” and is available here. As another example, in the movie Karate Kid (2010), Kung Fu master Mr. Han (Jackie Chan) takes Dre Parker (Jaden Smith) to the Dragon well on top of the mountain. Mr.Han explains the state of mind of the lady (who controlled the snake) which was calm and still just like the water in the well where Dre looks at his own reflection. The scene is available here (Watch from 1:13:00 to 1:17:10).

To give an analogy in the circuits and signal processing domain, when we need to acquire a signal, while ensuring quality and reproducibility in the digital domain for a given application, both internal and external noise have to either be minimized or rejected. In the same way, only a quiet mind can perceive and experience what is beyond hearing and also understanding. And often, the quality of listening goes with the choice of words one uses in his/her speech. As you begin to listen better, your thoughts become refined and so do your words. You then begin to filter all that is noise and only recover your signal of interest.

On another note, it is important to use one’s own discretion in placing the attention. Considering the information society we live in, there is a vast wealth of information on every subject. What we choose to learn is an individual choice. A wealth of information creates a dearth of attention, derived from the concept of attention economy, first studied extensively by Herbert Simon.

While we aim to bring about improvement in the the lives of people with hearing disabilities, we also need to give a thought towards how effectively we use our perfectly functioning abilities. How we take things for granted! If we didn’t, the experience would be more enriching, so much more happier and so much more wholesome!

As Helen Keller said,
So much has been given to me I have not time to ponder over that which has been denied.
This should not only motivate oneself to look within, reflecting on the challenges and converting every disadvantage to an advantage, but also placing a check on whether we use our inherent faculties to the total extent. It is just like owning a Lamborghini Aventador but being limited to use it as a Dacia Sandero on legal roads or employing an ARM micro-controller to make an LED blink!

                                                   ***
About Jiddu Krishnamurti

jk  Born (11 May 1895 ) in Mandanpalle, Andhra Pradesh, India, Jiddu Krishnamurti, an Indian philosopher, is globally regarded as one of the greatest educators and thinkers. He had a deep sense of appreciation and respect for nature, as it appears in his notes. When he spoke, he did so with his own insight and vision, which had a certain directness and freshness.

About Hellen Keller

hk Born (27th June 1880) in Tuscumbia, Alabama, U.S., Hellen overcame the adversity of being deaf and blind to become one of the 20th century’s leading humanitarians as quoted here.

Suggested reading and references

  • Commentaries on Living, Jiddu Krishnamurti
  • Education and the significance of life, Jiddu Krishnamurti
  • Story of my life, Hellen Keller

 

calvin

 

 

Optogenetics: lighting the way to the future

Article in Maxwell, the quarterly magazine of the Electrotechnische Vereeniging, ETV, Issue 18.4, by Farnaz Nassiri Nia, MSc Student in the Section Bioelectronics on the basic principles of optogenetics and a state-of-the-art bioelectronics application for the treatment of epilepsy.

The brain is the mystery of the human body. Neurons, as primary units of the nervous system, are joined together into a complicated biological interconnected network. A conventional method to manipulate the neural performance within this network is to use drugs that alter the chemical balance of the brain. However, a crucial aspect of the nervous systems is the electrical signalling between the neurons. Bioelectronics has advanced the neural modulation techniques beyond the conventional methods by developing electrical brain stimulation tools. Electrical brain stimulation is truly beneficial to understand the mechanism underlying neural behaviour, and develop novel therapeutic methods. Optogenetics is another breakthrough method in neural stimulation techniques, which has opened up entirely new avenues of research opportunities in the fields of neuroscience and bioelectronics. In this article, the basic principles of optogenetics and a state-of-the-art bioelectronics application for the treatment of epilepsy are described.

Een betere toekomst begint vandaag

maslov_eeVoor verwelkoming van de aankomende 1e-jaars van de opleiding Electrical Engineering aan de TU Delft maakte ik tijdens het “Electro Ontvangst Weekend” (EOW) een presentatie. Deze presentatie vind je hier: http://elca.et.tudelft.nl/~wout/tmp/eow_2015_serdijn.pdf.

Neural stimulation: design of efficient and safe neural stimulators

Article by Marijn van Dongen on efficient and safe neurostimulation

Article by Marijn van Dongen, honorary aluminus of the Bioelectronics Group, in Maxwell 18.3, the quarterly magazine of the Electrotechnische Vereeniging, on the work he did for his PhD studies on power efficient and safe neurostimulation.

Read the entire article here: http://elca.et.tudelft.nl/~wout/tmp/neurostimulation_maxwell_18.3_vandongen.pdf

Lecture on Electroceuticals: getting better with electricity

Lecture on Electroceuticals: getting better with electricity

Lecture on Electroceuticals: getting better with electricity

On May 6, 2015, Collegerama of TU Delft made video recordings of the lecture I gave on Electroceuticals.

Electroceuticals are the electronic counterparts of pharmaceuticals and are miniature electronic devices that interact with the body in an electrical fashion.

In this talk I discuss: neurostimulation and the need to make neurostimulators smaller, more power efficient and more intelligent; optogenetic neuromodulation and the need to make this new neuromodulation modality operate in a closed-loop fashion; neurosensing devices to make neurostimulators intelligent and thereby adjust themselves to the therapeutical needs of the patient; autonomous wireless sensor nodes that can measure temperature or the electrocardiogram without the need for a battery; an outlook into the future of electroceuticals with the promise to treat a larger variety of neurological and brain disorders better.

Click here to start watching the video and slides:

https://collegerama.tudelft.nl/Mediasite/Play/cc7888beb88349c1a60c1414476b577a1d?catalog=528e5b24-a2fc-4def-870e-65bd84b28a8c