GUMEE The Go-To Ultrasound Model for Endovaginal Education - HD

Introduction

I am Dr. Roya Soha, professor of Diagnostic Radiology and Obstetrics and gynecology at Oregon Health and Science University.

And today I'm gonna talk about a transvaginal ultrasound model for first trimester ultrasound called a gummy model.

Today we're gonna present the go-to ultrasound model for endo vaginal education, and the acronym is gummy and of course gummy bears are involved.

And I'm gonna introduce the fact that I did this with my stenographer, Aaliyah Martin a little bit later in the talk.

Background

Here's the background to the story.

The opiate residency coordinator contacted a group of us a few months back saying, I need to train my OB learners, especially the OB interns, how to do first trimester transvaginal ultrasound, to which I said, let's buy a phantom.

And she said, that's great. Why don't you choose a model? I'll look at my budget.

And therefore, I started to look at the commercially available phantoms for transvaginal ultrasound and learned pretty quickly that phantom sophisticated ones such as this were actually quite spendy.

This one was $7,000.

Here's a phantom without the blue towel.

And this one was also pretty expensive at $4,800 and less anatomically correct phantoms at yet serving the purpose of doing the ultrasound procedure were also quite spendy at $2,900.

So the conclusion was that these phantoms are quite expensive, and our goal was to actually have several dozen phantoms available and therefore that was not something that at our institution we could afford to do.

So we decided to create our own phantom.

And it also brought us to really look at what are the goals for having a model to practice transvaginal ultrasound.

Goals for the Model

I felt quite strongly that the first objective that we need to meet is to have the learner become comfortable with the machine before encountering a real person in that there will be less fumbling, at least with the left hand on the machine.

We also want the learner to be able to optimize the image and measure the first trimester structures accurately.

It's a very important time for dating a pregnancy, and therefore the learner really needs to know how to turn the transistor at least a bit to get the accurate measurements of the gestational sac to evaluate a yolk sac and of course, measure the embryo.

As we know, there is quite a bit of challenge with the neology as so many different machines have all different platforms.

Even, a one, machine producer will have several different platforms.

At our institution alone, we have three different platforms in the ultrasound, in the radiology department, the gyne folks in the OB clinic have several other ones, and so do the emergency room.

So it quite is a challenge to learn what to do at the machine for the appropriate scanning technique.

Then the objective number two that we considered, can you really teach someone how to scan on a phantom?

Can you really evaluate transducer manipulation, use the bimanual technique that you need to actually bring pelvic structures close to the transducer, find the structures that you need to, and can you really do this with a phantom?

And probably not was our conclusion.

And therefore this objective was put somewhat to the side.

So the summary for trying to come up with the perfect model for our purposes, and I hope for your purposes as well, is we wanted an inexpensive model.

So each learner or two could actually have their own model to work with.

We wanted to use materials that are readily available in a standard ultrasound suite or OB clinic without the need to prep before using the model.

I did not want to have the learners go into their kitchen and make gelatin molds.

I really wanted them to be able to use a model basically as they wanted to, as they had found time to practice scanning.

And also we decided that gummy bear, gummy bears would serve as the perfect embryo, their gelatin base, and therefore they're sono friendly.

They're available in most hospital gift shops and they're perfect for crown rump length.

And basically you only need one so you can eat the rest as you practice your scanning.

Development of the Gummy Model

I joined forces with a fabulously creative sonographer, Aaliyah Martin.

She was a student in our institution.

She's the person who, when she finished her training, made a rice Krispy cake of uterine pathology, even brought a transducer knife to cut this up thinking everybody would eat some of this in, which we didn't however you wanted.

I wanted to work with one of the most creative people in my department, and therefore, Ali and I came up with the gummy model.

And this is how the gummy model was born.

Materials and Building Instructions

So the materials necessary are ultrasound gel.

Ultrasound transducer covers both the endo vaginal and the transabdominal.

If one works in a clinic where transabdominal scanning is not performed, any other plastic bag, which is a little bit larger and could fit into a urinal would work as long as it doesn't have any holes in it.

We need small rubber bands, which come almost always with the endo vaginal transducer covers.

One needs a standard hospital urinal, water, scissors, and gummy bears and gummy bears come in all different sizes and it's at our institution.

These are organic blueberry gummy bears, but you can buy them at practically any store and gift shop.

The first step is to prepare the sack phantom.

A dollop of gel is placed at the end of the transvaginal probe cover.

And then you wanna squeeze out any air around this dollop and make a nice little sack, put a rubber band on it and cut it short.

So this is the empty gestational sack model.

If one of the small rubber bands is placed inside, then you have the yolk sack model.

And if the gummy bear is placed inside, that is the embryo model recommendation is to make all three.

Next, the phantom is placed inside the larger transducer cover, and this whole apparatus is placed inside the urinal.

It's really not necessary to secure the top at this point because we are going to go over to the sink.

So the plastic is moved to the side and the urinal is filled about a third with water.

And then the plastic is opened up and inside the, phantom is filled a third with water.

Next is positioning of the urinal.

We use towel rolls or anything that you have around to kind of reproduce the pelvic tilt of a transvaginal, phantom, what you would expect in a real pelvis in a female, and then introduce the transvaginal transducer without a cover into the model.

Imaging and Practice

So what kind of imaging is possible here?

I'm showing how we have recreated that pelvic tilt by putting the transducer at this angle.

And also you can put the phantom where you would expect the patient's pelvis would be in your own examining room and start scanning and practicing the ology and finding the phantom.

So these are the kind of images one can be expected to see.

Here's the gestational sack, and by tweaking it appropriately and turning the probe, we can see an intact ring.

This is a yolk sack model. You can measure it.

Obviously this yolk sack is too large and here is what the gummy bear looks like.

You can measure the gestational sac and also obviously the crown rump length of the gummy bear can be measured.

An additional step is you can have two learners.

One learner can measure the gummy bear.

Like I said, they come in different sizes and then make the phantom not sharing that information with the second learner, who can then measure the crown rum length and see if they're getting accurate measurements of the longest crown rum length.

This is an eight week gummy bear.

A bonus would be to do different things with this urinal model.

This is fluid within the larger, transducer cover.

And we put the smaller phantoms on the outside and this mimics the ovary, I'm sorry, the uterus and the ovaries.

And therefore learners can practice with that as well.

But our goal was really for the first trimester structures.

Implementation and Success

So did this work well at our institution?

I met one time with the OB residency director and gave her the recipe for the model and pictures of how to put it together.

My sonographer met one time with a perinatal fellow and a medical student, and physically showed them how to put the model together.

We gave them one sheet of paper, which had the instructions, which is also going to be available to you at the end of this presentation.

The instructions will be on one PowerPoint slide and we let them loose.

So they took the model along with other gelatin models and non gelatin models over to their ultrasound, training lab, which they do quarterly, and Aaliyah and I did not attend.

So these were folks really on their own putting it together.

This is an example of a faculty member working with a first year resident and a fellow working with a first year resident and other residents working independently.

These are third and fourth year residents, and you could see that the model could be used with a variety of different machines to learn how the machines are working and could be used independently or in conjunction with other, mentors.

The model was preferred over the gelatin transabdominal model, and again, took very little preparation.

Here it is being used on in, using a female urinal.

And the, in this case, they strapped it down, which is probably a good idea because then the model won't tip over as the, scanning takes place.

So we feel the proof of success of this model is that it's inexpensive using supplies in ultrasound labs with the addition of gelatin animals such as gummy bears.

It's reproducible with written instructions.

So you do not need special skills to put it together.

We've shown success in informal OB training lab.

It serves a great role in learning the ology and first trimester measurement skills.

And unexpectedly people who do have experience with ultrasound, they have used the model feel that it actually does replicate the feel of actually doing a transvaginal ultrasound.

And that was not the goal, but we seem to have replicated that at least a bit.

Conclusion

So thank you for your attention.

And the last slide again shows what the supplies would be for making the model and how to build it.

So I leave you with this. Thank you.