Jordy van Zandwijk

Jordy van Zandwijk

Technical Physician at the University of Twente. I work there as a researcher and teacher, and am part of the team developing the course on Ultrasound Imaging.

Location University of Twente, Enschede, The Netherlands


  • Okay, nice ones. But do you know what radar exactly means? I don't think there is any ultrasound involved in it :)

    But no worries, it's a common misunderstanding and often confused with sonar technology, which is used by the marine. Later on, you get to know that ultrasound works better with water than with air, so hopefully then it all makes sense!

  • Yes! Can you give specific examples in your own environment maybe..?

  • Isn't it wonderful!

  • You can make this animations very easily with programs like Matlab!

  • Hi Hanieh, subtitles are already added to each video! You can turn them manually of and on, so maybe in your videoplayer you have to turn them on (each time)?

  • Hi Santhirasegaram. I'm sure you'll learn more about US in this course that helps you understanding (personal) problems. Of course we focus a lot on the technique, but the physical and clinical aspects plays a role in some cases as well! (check out the physiotherapy case).

    Regarding knee problems, your support and musculoskeletal system should always be...

  • Nice to see the great variety of you! I hope to satisfy all your needs in this course, but for more questions or additional stuff you want to discuss, just let us know in the discussion!

  • Hi Fawzi, he has a very interesting case with some nice US images later on this week! Maybe you can say something about the case and similarities with your work/patients later on..?

  • Hi George, what a touching story you have. I hope you learn in this course more about US that helps you in hopefully an upcoming healthy future!

  • Care to elaborate on that Peter?

  • Welcome to you all who made it to the last week! I'm just curious, was it what you expected in the beginning??

    Good luck with the final week.

  • That is perfectly possible, I assume that for your hospital/country this is not obligated to do? What do you think of this?

  • Nice answers everyone! :)

  • Seems plausible, can you show your calculations to everyone? And I'm also not sure what you mean with a wavelength of 2m?

  • It can be, as a rule of thumb you can use that injecting 40 cc of air into a blood vessel will be lethal, which is a quite high number. Less volume of air by a simple syringe is therefore always be avoided since large bubbles may still cause problems (e.g. air embolisms). The air bubbles in here are microbubbles, which is the major difference with 'simple air'...

  • It is, but not that often. Especially for infants and newborns it can be useful. Can you maybe reason why, or what would be the problem??

    (think back of the content from Week 2!)

  • Good feedback, thanks! It is hard to imagine this if you haven't done or seen this before, so also for me a bit hard to explain it only by means of a video. What I did simultaneously with the real probe should have been exactly the same as what the simulator shows you by the way.

    But I agree that this could have been improved.

  • I know, silly name... :)

  • Indeed that is very important. Do you know places were US machines are that you can use for training?

  • Hint: Use the formula from the video

  • Hi Stephen, that's the question! Do you have an answer on that?

  • The answer is in the first part of your reaction. Also, check the tabel underneath the video. Velocity is determined by the type of tissue.

  • Do you mean like quantifying this?

  • Wouldn't that mean that the acoustic impedance would change all the time? What do you think of that?

  • This is indeed a bit more difficult, but we're getting there!

  • Maybe let it sink in for a while, and re-read it another day? :)

  • Nice comparison, like!

  • You will be imaging different areas/anatomy. Is that what you meant with your question?

  • Good to see you replying here, don't forget to take a look as well on the Padlet wall, and maybe even share some thoughts and ideas over there as well!

  • Yes! Can you think of other applications for the mobile version as well?

  • What did you wanted to know from this video? Maybe what you expected will be discussed later in the course..?? Please let us know if you have improvements!

  • They are not using anything, this has to do with the anatomy of their inner ears. There is a structure that can 'capture' different frequencies, and this structure differs in length (so more or less frequencies) between animals.

  • If you consider the formula mentioned in the video, then indeed if you change frequency the wavelength changes. But do you also know now what determines the velocity of the sound wave?

    (Hint: it has nothing to do with the US system..)

  • Then I think you will be lucky this week!

  • Hi Marzena, you are absolutely right, since there are of course situations where US can be immediately helpful in case of emergency. We should have nuanced this and where perhaps too much generalizing. Life functions are always the first thing you should consider, but sometimes US aids you in how to restore the right life functions.

    Thanks anyways for your...

  • And at which places would you measure Maartje?

  • Would you measure only at the stenosis or are there also other places?

  • Remember that it's just a monitor displaying information. With basic HDMI cables you can split/transfer the signal to any other device with HDMI input you like! Can be very helpful, especially for demonstrations or ultrasound education.

  • Good! Do you like other cases as well?

  • You will pick up more knowledge throughout the course, and hopefully you will be able to understand this better in the end! (and maybe even be able to solve our case :)

  • Very good reference, nice illustration here. Perhaps we should include the link in the article don't you think?

  • Please try to also give explanations to your answers! This can help others to understand your reasoning as well and may lead to new ideas for the ones that are less experiences with the technique.

    Besides, I see a lot of satisfying answers :)

  • Very nice to see the variety of you here. I sincerely hope there will be something new and exciting for everyone. I see a lot of professionals here who want to benefit immediately from this course. I would like to know in the end of this has worked and how it influenced daily work for all of you.

    Enjoy the course!

  • I hope so! This is exactly how we made the course and how it should be.

  • Hi all! I'm very excited to see how you experience the course. Please let me know if there would be anything I can do for you or help you with during the course. Good Luck!

  • Very well! What is the most important setting that you learned to tweak Juliet?

  • Good to know Sunday! Did you also post something on the Padlet wall?

  • Again, a wonderfull overview and a nice additional website you provided us with A Mitchell! It is also good at the second point to think about the exact location where to measure with respect to the (suspected) stenosis. Do you measure before, at, or after this stenosis?

  • Very nice overview of steps that you would take. What about the transducer frequency at point 1, how would you change this?

  • Interesting to see your thoughts about anisotropy A Mitchell, and that it won't be a reason since two different orientations were used in this case. Did you also consider that in the different orientations you still have multiple degrees of freedom to tilt and angulate your probe around the interesting structures?

    And those are some nice links you added, I...

  • Of course Valia! Let us know if you need help on some topics!

  • It's good to see you posting your thoughts here, but also don't forget to go to the Padlet wall and see what many other learners have said/thought before you!

  • Nice to see the great variety of learners that joined us in this course!

  • Good to see you all here, I hope that you'll learn something from this course!

  • I see that some of you do a great job in showing the underlying math for this concept, well done! The most important thing, however, is to give an interpretation on the math that you did. Some of you do this very well, but if you haven't done so already go give it a try!

    What do you think a ratio Pr/Pi of 0.99 means?

  • Yes, thanks for the explanation Yoeri. This is the main reason that your temporal resolution decreases if you use this technique. You can use your time of flight knowledge to demonstrate this principle of a decreased temporal resolution.

  • Don't forget to post your input also on the Padlet wall, so your fellow learners can quickly overview all the reactions!

  • Hi Emma, this is perfectly possible, although you still use ultrasound live to get immediate feedback of what you are imaging. What kind of complex processing do you think of?

  • You will see this later on in the week from a 'familiar face'!

  • Yes really! :) How would you call it?

  • Hi Deborah, I'm not quite sure what you meant with this comment. Can you maybe rephrase your question or feedback for us? Thanks!