Cherie Young: Hello, my name is Cherie Young. Today is September

3rd, 2025 and I'm interviewing Dr Leo Happel on behalf of the

ASET Historical Advisory Committee. Thank you for being

with us today, Dr Happel.

Dr. Leo Happel: My pleasure.

Cherie Young: Great. So, Dr Happel, you are currently

retired, correct?

Dr. Leo Happel: Retired in quotes, as I was explaining a

little bit earlier, when you when you are in academic

medicine and you teach students, your students always feel like

they have the prerogative of calling you when it's necessary,

when they need something explained. And so I have a lot

of surgeons that I had no contact with previously who call

me and ask me questions and try to get me to explain what they

are seeing in the operating room. This is becoming much more

common now since my former head of neurosurgery, Dr David Klein,

passed away about six months ago, and so all the calls that

used to go to him now come to me, and sometimes it gets really

tough.

Cherie Young: Yep, so there's no such thing as retirement, right?

Dr. Leo Happel: Exactly, except that you don't get paid anymore.

Cherie Young: Right? Where did you receive your credentials for

intraoperative monitoring?

Dr. Leo Happel: I received my credentials when I was hired by

LSU medical school. I was hired by Dr Richard Patterson, who was

then the head of neurology, and he appointed me an Assistant

Professor of Neurology, even though I am a PhD, not an MD.

And so as a member of the faculty of the neurology

department that automatically gave me credentials at Charity

Hospital New Orleans. Charity Hospital, New Orleans was a

teaching hospital, and so the teaching faculty came from both

Tulane and LSU medical schools, the clinical departments. If you

had a clinical appointment, you automatically had the privilege

of seeing patients at Charity Hospital and performing testing

on them, and that was how my credentials got started. I had

to go through the process of acquiring other credentials. I

had to show proof of malpractice insurance, because you can't do

anything clinical at Charity Hospital unless you had

malpractice insurance. I had to go through training in basic

life support, because as a clinical faculty member, BLS

credentialing was required. So I had to show proof of training in

CPR. I had to be tuberculosis vaccinated. And with those

credentials, added to my academic credentials, I was

approved for seeing patients at Charity Hospital,

Cherie Young: Very good. And what drew you to evoked

potentials in intraoperative monitoring? How did you get into

that specific notch in diagnostic testing?

Dr. Leo Happel: I guess I have always been an electronics geek,

and as an electronics geek, when I was in graduate school, I

familiarized myself with a lot of electronic equipment and

basically did research in evoked potentials using the

instrumentation that I had familiarized myself with.

Cherie Young: Very good. So this wasn't very popular when you

started your career? You're one of the original pioneers,

correct?

Dr. Leo Happel: It was fundamentally nonexistent, and

the reason it didn't exist is there was no instrumentation

that was in one box. You couldn't go to the company

Nicolet because that didn't exist. You couldn't go to any of

the other vendors of evoked potential machines to buy a

machine, because they didn't exist. So what was necessary was

to assemble a cart with all of the appropriate equipment. I had

some GRASS amplifiers, and the GRASS amplifiers were

particularly good for two reasons. Number one, these

amplifiers had a very rapid recovery time, and so whenever

they whenever the instrumentation was smacked by a

large artifact like the electro surgical unit in the surgeon's

hand, these amplifiers would recover very quickly. And

another feature that these amplifiers had was they were

optically isolated, so there was no grounding associated with the

amplifier systems. And this was extremely important, especially

at Charity Hospital New Orleans, because Charity Hospital New

Orleans was a very old building, and all of the electrical wiring

in this building was not electrically isolated like it is

in all of the operating rooms today.

Cherie Young: Wow.

Dr. Leo Happel: So the optically isolated amplifiers helped a

lot. In addition, I had some GRASS stimulators, and the GRASS

stimulators were also optically isolated, and that precluded the

necessity for grounding. Grounding was a real problem in

the early days of neuromonitoring, because one of

the terrible things that would occur was the creation of a

ground loop. And in order to try to avoid ground loops, I

proposed something called Happel's law. And I don't know

if you remember Happel's Law. Happel's Law was "never, ever

attach more than one ground to a patient, it is never proper

technique". Anytime a patient has more than one ground on

their body, it is possible for their body to become involved in

an electrical current path that is part of a ground loop and

electrical burns from the operating room were relatively

common in the early 1970s.

Cherie Young: Wow. So we've overcome a lot of challenges

with our equipment these days. Wouldn't you say?

Dr. Leo Happel: Absolutely, the equipment manufacturers have

really done a great deal for technologists who actually do

the actual work. The inclusion of optical isolation in both

amplifier systems and stimulator systems really precludes the

possibility of ground loops. And so that is a huge help for us,

and takes away a lot of the risk associated with working in the

operating room. Operating rooms are intrinsically high risk

environments. They are very high electrical noise environments,

and they present us with lots and lots of problems. One of the

problems I had with working at Charity Hospital was the

operating rooms there were extraordinarily small. These

rooms were no more than 10 feet by 10 feet. And anytime you

start packing in a lot of equipment, the room just

disappears very quickly. I remember walking into another

hospital and walking into an operating room suite and looking

at the operating room and marveling at how big this

operating room was, and the operating room there got to be

very small by the time you put an EEG machine, stimulators, an

X-ray C arm, and all of the trays of instruments that the

surgeons needed by the time you put all that in the room, the

room got suddenly very, very small.

Cherie Young: Oh, my goodness. You've obviously created an

environment to test and record evoked potentials in the

operating room. Who would you say was the first manufacturer

of this equipment?

Dr. Leo Happel: The first manufacturer of the computer

that I use was a company called Fabritech, and Fabritech made a

computer of average transients, and that's what we needed to

have to do, the computer averaging that we do in

monitoring. Fabritech was a company that was later purchased

by Nicolet, and so it later bore the Nicolet name, but it was

nevertheless the same company.

Cherie Young: Okay, I remember back in the day a Tektronix. Was

that a computer you had built?

Dr. Leo Happel: Tektronix was a display. Tektronix is a

manufacturer of oscilloscopes. And so when I did surgical

monitoring, not just to do for spine surgery or brain surgery,

but for peripheral nerve surgery as well, the Tektronix became

the principal source of amplification and display.

Tektronix is a paragon name. Tektronix is a top of the line

oscilloscope and top of the line manufacturer, and this was

absolutely necessary to deal with all of the electronic

problems that we would encounter in the operating room. I have to

go back a few steps. I started working at Charity Hospital, not

in the operating room, but in a program of research that the

neurology department was conducting. The Department of

Neurology was trying to study the development of the human

brain, and the way they did that was recording evoked potentials

of neonates and then following those neonates over a period of

about eight years and watching the development of evoked

potentials as the brain developed.

Cherie Young: Wow. Very interesting.

Who would you say are some of your early mentors and earliest

influences in your career?

Dr. Leo Happel: This is kind of interesting. I'm glad you said

early influencers, because there were no real mentors. There was

nobody who had real expertise in operative monitoring. Some of

the people who were the early groundbreakers, there was a

fellow by the name of Augie Mohler. Augie Mohler, was

particularly good in the area of brain stem auditory evoked

potentials, and this is something that he performed

during the removal of acoustic neuromas, and he was able to

tell the surgeons what was happening to the point where he

dramatically improved the outcomes of brain stem auditory

evoked potential testing during acoustic neuroma removal. I

would like to mention as a learning issue here, to this

day, many people feel that if someone has an acoustic neuroma

in, let's say, their left ear, there is no reason to do

brainstem auditory evoked potential testing on their left

ear, and they just leave all that off, and they only do the

right ear to measure what's happening in the right

brainstem. And that's not really good technique. And the reason

for that is, when a person is deaf from an acoustic neuroma,

most of the time they still maintain a wave one of the

brainstem auditory evoked potential. Wave one of the

brainstem auditory evoked potential originates in the

distal eighth nerve. If that eighth nerve action potential is

still present, it indicates that the arterial blood supply to the

eighth nerve and to the cochlea is still intact. The blood

supply to the Cochlear artery comes through a blood vessel

that we call AICA, A, I, C, A, anterior, inferior cerebellar

artery. And this artery supplies several things in the brainstem

that are very much important. So it's still a good idea, even

though a patient is deaf in one ear due to an acoustic neuroma,

it's still a good idea to do the brainstem auditory evoked

potential testing on that ear, because it will still tell you

something about the blood supply to the brainstem.

Cherie Young: Right.

So really, when you started, there was no training program.

You did the training with physicians on personal nerve and

moved over into evoked potentials and intraoperative

monitoring. Where do you see us going in the future?

Dr. Leo Happel: Wow, that is a really tough question to answer.

Cherie Young: Certainly, we've come a long way from where you

started.

Dr. Leo Happel: One of the problems with neuromonitoring is

that it gets to be expensive. The equipment is expensive, the

personnel required to do it gets to be expensive. One would think

that it would be very easy for a single individual to bring the

equipment in the operating room and record evoked potentials

from a patient who is under anesthesia. It doesn't work out

to be quite that easy, and the reason for that is the surgeons

use some equipment that introduces vast amounts of

artifact in the records. And if there is one thing that a

computer system does not like, it's artifact. Transients that

are presented to the equipment doing evoked potentials creates

a noise problem that is so bad that it destroys the computer's

ability to demonstrate the evoked potential. So we usually

have to have two people in the operating room, one person

watching what the surgeon is doing. And I remember that the

early techs that worked with me would stand by me and stand up

tall enough that they could see over the drapes and see what the

surgeon was doing. And when the surgeon got ready to use the

bovy, the electro surgical machine, I'd get a tap on the

head, and I could quickly turn the inputs off, so that this did

not get into the computer and mess up the cumulative average

of what was going on. So all of this adds to the expense. And if

there's one thing that the medical insurance companies do

not like now, it's expenses, and so they try to cut back on

costs. And unfortunately, one of the things that's happening

right now is there are many insurers who designate that they

will not cover operative monitoring, even though

operative monitoring has clearly demonstrated that it improves

the outcome of particular surgeries. This happened first

with the brainstem auditory evoked potentials and acoustic

neuromas. When neuro monitoring was used in the case of removal

of an acoustic neuroma, the outcome statistics was so much

better than if monitoring was not used that some societies

like the American Academy of Neurology came out with a

position statement that said, if you'd removed an acoustic

neuroma without using auditory monitoring, you were practicing

substandard medicine. And got to be a very profound issue for a

long time, and to this day, most ENTs will use monitoring in the

case of acoustic neuroma removal.

Cherie Young: Scientific knowledge has certainly changed

in our field. What do you think were some of the big

breakthroughs, because you've seen it all starting from the

beginning. What do you think is one of our biggest

breakthroughs?

Dr. Leo Happel: One of our biggest improvements? The bottom

line and the bottom line is outcomes are better because of

neuromonitoring and it's hard to put a price on an improved

outcome, and that's why we have to argue with insurance

companies many times in order to get them to reimburse. We had an

issue once later on in my monitoring career, when there

was an insurance company that said, "Well, we're simply not

going to pay for it. If you want to do it, that's fine, but we're

simply not going to pay for it". And that put me in an awkward

position. I had to go to the surgeons and tell the surgeons,

look, I can't do this for free. This costs a considerable amount

of money, so I'm going to have to stop monitoring if insurance

is not going to reimburse for this. And so then the surgeons

said, "Well, I can't do the surgery without this". So he

would go to the administrator of the hospital, and he would tell

the administrator of the hospital, we're not going to be

able to do this kind of surgery. And the hospital would come back

and say, "Oh, well, but that's a very common procedure, and we

encounter this pathology often, and so we have to have you do

the procedure". And so we said, "Well, how can we arrange this"?

The hospital said, "Well, we will pay for the

neuralmonitoring by contract. We will contract with people who do

neuromonitoring and get them to perform the neuromonitoring, and

we will pay for that and the hospital at the end of the year

has a financial facility that they can turn to and things that

they are not reimbursed for they can charge off to various

governmental agencies. And so we're back in the situation

where we have the ability to finance neuromonitoring. And I

think most people would choose to use it because of the

statistically improved outcomes of surgeries that are monitored

compared to those that are not.

Cherie Young: That's correct. That's why we do what we do,

better patient outcomes, right?

Dr. Leo Happel: That's the bottom line.

Cherie Young: What would you say you're most proud of in your

professional life?

Dr. Leo Happel: The thing that I'm most proud of? I'm proud of

the teaching that the societies associated with neuromonitoring,

like ASNM, the teaching that those societies do. The

credentialing that the American Board of Neurophysiologic

Monitoring does, that basically indicates the person that's

doing this neuromonitoring is adequately trained. That's what

I'm most proud of, that we have created a plane of expertise,

and this plane of expertise can now be certified.

Cherie Young: Right, and you were a pioneer in the

development of some of these programs, like what we know as

ASNM today started out as...

Dr. Leo Happel: American Society of Evoked Potential Monitoring.

ASEPM. That's how it started out. That's the society that

first started off. And as the society evolved, they changed

its name to ASNM. And yes, I was a founding member of that

society. I was also a founding member of the American Board of

Neurophysiologic Monitoring, and I'm proud that I was able to do

that, and that we were able to examine people and certify that

indeed they had an adequate knowledge base to be doing

operative monitoring. Those were very good things to have done.

Cherie Young: Absolutely. What do you think was the best piece

of advice that you've ever received?

Dr. Leo Happel: Keep your eyes open and your ear to the ground.

Not the electrical ground, but... I had an unusual

opportunity in my career at LSU. When I was in the Department of

Neurology at LSU, there was research going on at the Delta

Regional Primate Center in Covington, Louisiana, and once a

week, I would go over there with either Dr Hector LeBlanc, Sonny

LeBlanc, or Roger Smith. And we had research going on primates

over there, and I had the opportunity to actually do some

of the surgery on the spinal cord of primates myself. This

gave me an opportunity to actually watch what was

happening to the blood vessels as I worked on the spinal cord,

and I gained a very healthy respect for the phenomenon of

vasospasm. When you mechanically stimulate blood vessels, you can

cause the smooth muscle of those blood vessels to constrict, and

that shuts down the blood vessels. And I was very much

sure that this same thing was happening when spine surgery was

being done on human subjects. As a consequence of that, I learned

my first principle of if the evoked potential monitoring

tells me something bad is happening, I will turn to the

anesthetist and ask them to raise the blood pressure. That

elevation of the blood pressure helps to prevent or reduce the

amount of vasospasm that occurs as a consequence of manipulation

of the blood vessels of the spinal cord. So that got to be a

very common thesis, and I think most people today will do the

exact same thing if they're in a surgical procedure, and during

that surgical procedure on the spine, the evoked potential

monitoring is changed. The first instinct that they have is to

raise the blood pressure and see if they can get the function to

return to what baseline was.

Cherie Young: If you were given the chance to interview anyone,

who would you choose in the field, to interview?

Dr. Leo Happel: One of the very authoritative people in

monitoring acoustic neuroma resection was Augie Mohler, and

unfortunately, Augie Mohler has passed away now, and he's not

available for an interview, but he was a very authoritative

figure, and his knowledge of neuroanatomy and neurophysiology

associated with the auditory system was very comprehensive,

so he would be a good person to learn from.

Cherie Young: Yes, and thank goodness we have his books with

all his stuff.

Dr. Leo Happel: Yes, we do have his book at least. And his book

is still very authoritative and still commonly used as a

referral point.

Cherie Young: So it's hard for me to believe, as you taught me

IOM, I was one of Happel's girls. I can't imagine you doing

anything else in your life, but if you wouldn't have gone into

evoked potential intraoperative monitoring, what profession

would you have chosen?

Dr. Leo Happel: Maybe I could have become an itinerant ukulele

stringer or something like that. I don't know what I would have

done. I had all of the background in electronics, in

physiology. My interest was in spinal cord function. And when I

was presented with the opportunity to join the faculty

at LSU and go into this area, with no reservations I jumped at

the chance.

Cherie Young: And you've done a wonderful job. You've taught so

many. What was your PhD in?

Dr. Leo Happel: My PhD was in neurophysiology. After I came to

LSU, I was only at LSU doing evoked potential recordings for

a period of about three months when the head of the

neurosurgery department, Dr David Klein, noticed what I was

doing and realized that I could help him out a lot. And so he

went to the head of the neurology department and told Dr

Patterson, "I want him in my department too. So I'm going to

make him 30% neurosurgery and 60% neurology". And so I got to

work with Dr David Klein, who was a world authority in

peripheral nerve surgery. I started doing a huge amount of

monitoring peripheral nerve function during neurosurgery for

peripheral nerve injury. Dr Klein passed away, I guess,

about eight months ago, and before he passed away, we tried

to put a comprehensive review of what we had done over the course

of 40 years monitoring peripheral nerve surgeries, and

the numbers that we came up with just blew me away. Over the

course of 40 years, we recorded data from 27,000 peripheral

nerve injuries. It made me realize why I got so tired. We

did it a lot, and some of these surgeries would last for long

periods of time. Dr Klein was particularly motivated in and

interested in surgery to the brachial plexus. Those surgery

procedures for brachial plexus injury would often last 18 to 20

hours, and we would be in the operating room for 18 to 20

hours recording peripheral nerve activity as he evaluated

different components of the brachial plexus. We had ample

pathologic material. The city of New Orleans had a very active

chapter of the Knife and Gun Club, and so as a consequence of

that, peripheral nerve injuries, especially to the brachial

plexus, were quite common and we did so many of those.

Cherie Young: I also want to ask you, how did that evolve into

spinal monitoring?

Dr. Leo Happel: I came to LSU in 1970 and so I got involved with

doing evoked potential recordings in the collaborative

Child Development Program and with teaching EEG techs. And I

did that for quite a few years, until finally, Dr Andrew King

asked me if I could do evoked potential recordings during

spine surgery. And I said, "Yeah, I think we can do that".

And we did one case at Charity Hospital, and the outcome from

this case was particularly good. This was a young man who had a

severe kyphosis, and during his correction of this kyphosis, we

lost all spinal cord function. When I told him that he was

really upset, and so the only thing he could think of to do

was to release the correction that he had placed on this young

man's spine. And when he released the correction,

instantly, spinal cord function returned. And so he put some

correction back, but not as much as he had originally, and the

spinal cord function was maintained. And the bottom line

of this case was, when the patient woke up, he was capable

of walking, using his legs, his spinal cord worked just fine. So

Dr King then asked me, "Well can we do this at Children's

Hospital?" And so I said, "Well, you know, I'm not credentialed

at Children's Hospital, but I have my credentials at Charity

Hospital, and we'll see what we can do." At that time, the

medical director of Children's Hospital was an

anesthesiologist, Dr John Heaton. Dr Heaton was a very

imaginative guy and a very forward looking guy, and he

said, "Yeah, let's see what we can do here". And so the only

way I could get on the staff of Children's Hospital was to be

hired by Children's Hospital as a contract employee under the

direct supervision of Dr Heaton, and this is how it came to pass.

So we started doing operative monitoring on the big spine

cases, on some of the brain stem cases, some of the neurosurgical

cases, and that's how neuromonitoring got started at

Children's Hospital. Over the course of many years, Dr King

and I have worked together, and we have many instances where we

have been able to identify an evolving problem that was highly

correctable, which we corrected with the outcome of a good

result from the surgery. And so I have to thank Dr King for his

efforts in getting me to work at Children's Hospital.

Cherie Young: So you were not only neurology, neurosurgery,

now you were orthopedics too.

Dr. Leo Happel: That's right, I actually got to do a lot of

orthopedic cases. And some of the orthopedic cases even

expanded beyond spine. During cases of hip replacement, it was

necessary to disarticulate the hip joint. And the orthopedists

who were doing that noticed that there was a lot of incidents of

peripheral nerve injury when the sciatic nerve was extracted and

pulled on to dislocate the hip joint, often it created an

injury to the sciatic nerve, and yes, we can monitor for that. So

that became one of the procedures that we would

frequently monitor. I would add not only orthopedics to what we

monitored, but the urologists got real interested in what we

were doing, and wanted to know, could we monitor from pelvic

floor nerves, because they had a lot of incidents of pelvic nerve

injury in the pelvic floor and so we started doing that. And as

we did that, the urologists actually got their own system

going, and they had their own people and their own equipment

to monitor urologic function during pelvic floor surgeries.

So it grew. It grew very, very rapidly, and I am grateful to

have participated in that.

Cherie Young: Through the years, when I started working in

intraoperative monitoring, in the beginning, we were only

doing somatosensory evoked potentials. Do you remember

that?

Dr. Leo Happel: Yes, I do.

Cherie Young: And we evolved together with your oversight.

Dr. Leo Happel: The spine surgeon said, it's nice to be

able to prevent problems to the sensory system, but what we

really want to do is we want to protect the voluntary motor

pathways. And so in the 1980s there were people who were

trying to develop a method to evaluate the motor pathways, and

they started off with trying to do transcranial stimulation of

the motor cortex to evoke movement that we could then

record an electrical event associated with and thus assess

the motor pathways. This was crude to start off with, and the

parameters of stimulation were a little bit scary. This motor

evoked potential process began at St Louis, in the hospitals at

St Louis, and they would stimulate transcranially using

electrical pulses of about 2000 volts. And I remember going to a

meeting once where somebody stood up and asked, "don't they

call that capital punishment"? Well, be that as it may, we got

better and better at it, and we got the techniques of

stimulation the motor cortex down a little bit better where

we could use much, much lower voltages, and that was much more

appealing. And now there is a fairly common use of motor

evoked potentials during spine surgery as well as somatosensory

evoked potentials. The more tracks that we can evaluate

during surgery, the more accurate we can be in stating

that things are working okay. The surgeons got to be pretty

demanding. And as surgical procedures were underway, they

would frequently ask, "How is everything"? And expecting an

instantaneous response, which we couldn't give. It took about

three minutes to perform the testing that would evaluate

these pathways, and we would have to say, "Well, you know,

give us a couple of minutes. We'll let you know in a couple

of minutes if everything is okay", which we had to then do

the testing, and then we could give them a response to say yes

or no, everything was okay or not okay.

Cherie Young: And to facilitate some of those requests, I recall

you being able to create instrumentation maybe, to help

us along the way.

Dr. Leo Happel: Yeah, we had several things that we could

use. I'm not really a surgical equipment manufacturer, but

there were pieces of surgical equipment that we could use that

would facilitate these recordings. But that was

something that really has not become very commonplace. Most

places still use transcortical stimulation and the recording

from muscle groups in the legs to see if there is conduction in

the motor pathways.

Cherie Young: And before that time, remember when we started

descending evoked potentials, before we had the motors, we

were doing descending evoke potential stimulation. And I

remember we had to apply the needles, but they had a Teflon

coating. So you would actually shave those needles for us to

remove some of the Teflon coating so we could stimulate.

Dr. Leo Happel: We could stimulate cervical spinal cord

and record motor events in the legs. That was a process that we

went through for a while, but then eventually the

transcortical stimulation took over from there, and it was a

little bit easier to place electrodes on the scalp.

Cherie Young: Right? No more shaving down electrodes.

Dr. Leo Happel: No more shaving down electrodes, no more

trying...

Cherie Young: And having them re-sterilized. And I remember,

in one of the cases they'd asked for the Happel adapter. Tell us

about that?

Dr. Leo Happel: Oh, uh.

Cherie Young: I remember all kinds of things.

Dr. Leo Happel: Yeah, you remember better than I do. I'm

trying to remember what that was. I remember we had an

adapter, but I don't really quite recall what that was.

Cherie Young: It was part of the stimulation process. Might have

to refer to Andy King on that one.

Dr. Leo Happel: Yeah, it can refresh my memory here. I hope

I'm not having the same problem that my wife has. My wife has

Alzheimer's, and so this really changed my course of action,

because my wife started to develop Alzheimer's about 2015

or so, and I was her primary caretaker. And I was her primary

caretaker until 2023 when I had an event myself. I had an

intestinal bleed, and in the middle of the night, one night,

I almost bled to death. And that changed the course of pretty

much everything for me. Following that bleed, I got to

be very weak, and in early 2024 I fell and broke my ankle. And

the orthopedist that I went to, x-rayed my leg, x-rayed my

ankle, and he told me, he says, "You know, I've seen this happen

time and time again. I can put plates and screws on the broken

bones, but I can tell you that if I do that, you're going to

have a lot worse arthritis than if I just leave it alone and let

it heal". And so I took his advice, and I let it alone, and

it has healed, but it still gives me problems. I still have

to walk with a cane, and so have not quite recovered from a

broken ankle.

Cherie Young: Goodness. Well, we're sorry to hear about Bonnie

and yeah, sometimes we have to make hard choices in life. It's

not easy.

Dr. Leo Happel: Yeah, it really isn't. It really is not.

Cherie Young: So I'd like to hear one more story from you. I

want to hear the story, since you've retired, the call that

you recently received. You said, people still call you.

Dr. Leo Happel: Yes, okay.

Cherie Young: Let's talk about that quick call. Well, it wasn't

a quick call. It was a quick call to you, but it was (laughs)

Dr. Leo Happel: Okay. Here's the story. There was a young man who

was born with a birth injury to his right brachial plexus. This

injury was so bad that he had a flail arm as a result. He had no

voluntary movement in his arm, and so it was not a good idea to

try to repair this injury right away. The surgeon chose to wait

and see what was going to happen, and he waited till the

child was six years old. When the child was six years old, the

neurosurgeon chose to do surgery on his right brachial plexus,

and he calls me on the telephone. He says, "I'm in the

operating room now", he says, "I've got his brachial plexus

exposed". He says "I'm stimulating elements in his

right brachial plexus, and I'm watching his right hand and the

fingers of his right hand move. How can that possibly be? This

child has no voluntary movement whatsoever. How can that be?

What does it mean?" And so I explained to him, over the

course of six years, this child has had a small number of axons

grow from his right brachial plexus all the way out to the

intrinsic muscles of his hand. These fibers are very few in

number, and they create very small motor units. What you are

doing when you stimulate is you are artificially synchronizing

what few motor units remain, going from his right brachial

plexus down to his hand, and those few motor units, when they

are synchronized together, can produce visible contraction of

his hand. However, those motor units are so small that they

cannot be incorporated into voluntary movements to create

voluntary movements of his right hand. So you have to treat this

as if this was a complete injury to his right brachial plexus,

and those elements in his right brachial plexus still have to be

repaired. That was a complicated picture, and it was a call that

I had to make that indeed, his injury was still complete. It

was not a case of his injuries had healed. It's just that the

case of those nerve fibers grew back, just a few of them over

the length of his arm, and they could now mediate movement if

they were synchronized by electrical stimulation.

Cherie Young: Very impressive. You never cease to amaze me Dr

Happel.

Dr. Leo Happel: Oh, well, this what I was meant to do. This was

my calling.

Cherie Young: I truly believe that.

Dr. Leo Happel: I had the electronics background, I had

the biology background, and the circumstances just came up where

I could pull all of that together, and it created a

wonderful career for me.

Cherie Young: Right? Well, I would like to say thank you very

much for taking the time to do the interview. From ASET

Historical Society, we truly appreciate the opportunity to

interview you today and hear all of your history and how evoked

potential and intraoperative monitoring have evolved today.

Dr. Leo Happel: Well, it means a lot to me that you were the

person on the other side of the screen here asking the

questions, because I have to tell you that I appreciate all

that you have done. You know you were a gifted person, and I

recognize that you were a gifted technologist, and I have had

ample opportunity to recommend you as someone who was

particularly capable. So it's been a pleasure working with

you.

Cherie Young: Thank you very much. That is very sweet. I

wouldn't be where I am without your help, and

Dr. Leo Happel: probably works both ways

Cherie Young: You were my mentor and I was excited when I was

asked to do this interview for you. So...

Dr. Leo Happel: Cool. Well, I'm glad to do it. Glad to do it for

the society. Glad to do it for you in particular.

Cherie Young: Dr Happel, you've done a significant amount of

research in our field, and I'm sure you have been awarded.

Dr. Leo Happel: I have been and it was indeed a great and

special honor that was conveyed on me at the ASNM meeting in

Orlando, Florida, I was designated as the recipient of

the Richard Brown Lifetime Achievement Award in operative

monitoring, and I still have that plaque, which has a special

place in my heart. Richard Brown is no longer with us, but he was

a very good friend during his lifetime, and he really meant a

lot to me.

Cherie Young: Well, we appreciate you being one of the

pioneers in our field and sharing your wealth of knowledge

with all of us.

Dr. Leo Happel: Thank you very much.