Tuesday, July 5, 2016

A trip to see Dr. Hertle

A trip to see Dr. Hertle in Akron, Ohio

Today we went to see Dr. Hertle in Ohio.  I can't believe it's been 10 months since we initially found out about Jesse's nystagmus.  We were so worried and scared.  Now he's an active 13 month old, walking everywhere, and trying his hardest to keep up with his brother, Max.

Fortunately Jeremy's parents live only about 1.5 hrs from Akron, Ohio, so we were able to combine the trip to Dr. Hertle with a family vacation and July 4th picnic (more on that later).
The facility at Akron Children's is small but nice enough.  Our appointment was at 10am and they were right on time.  The staff was very pleasant and everyone was super friendly.


First we saw Dr. Hertle for a quick introduction.  He almost immediately noticed Jesse's head tilt of about 10-20 degrees down.  I had long suspected that he had a null point up (chin down), but his chin was never planted in his chest, so it's not super noticeable, especially because he doesn't use it all the time.  Apparently most kids will eventually elect to stop using the null point because it hurts their neck and back, but then of course this means that their vision is worse because they aren't using the part of the eye that allows for the best sight.

Eye Movement Recordings

Next up was the Eye Movement Recordings (EMR).  For these Jesse's eyes were recorded for 3 minutes with an infrared camera in a dark room.  He did pretty well and we finished on the first take.  They also did a 1 minute standard video recording with the lights on.  This was fairly well tolerated.


Visual Evoked Potential

After the EMR was the Visual Evoked Potential (VEP).  This test is done to test the optic pathway between the eye and the brain.  This was the most difficult test.  Jesse was not happy.  For the VEP they place a large electrode on the forehead and three smaller ones on the back of the head.  They also place a probe on their right ear.  They then cover up each eye and show a series of black and white checkered images on the screen.  Each image has a red dot in the center and they last for a minute, with the image moving slightly.  I think they need about 4 good recordings per eye.  The key to good waveforms is that the child must remain calm and look at the screen for the whole minute.  Jesse did amazing and we were able to get all the recordings done in a short amount of time.  I think we wound up having to do 6-8 recordings per eye to get good ones.   To keep him calm we sang songs and dangled little fake spiders and frogs in front of the screen on strings.  I will say, his head tilt was very noticeable during the test, which makes sense because he was concentrating so hard on the screen.

(VEP right eye)

(VEP left eye)

Eye Exam

After the VEP test they dilated Jesse's eyes for his final exam, which was an eye exam by Dr. Hertle.  Since Jesse was happy and alert, Dr. Hertle was able to do his eye exam in about 5 minutes.  Obviously he's not old enough to read an eye chart, but Dr. Hertle did look into his eye for pigmentation and any refractive error.

After all the tests were done (about 2 hours for us because Jesse was happy and cooperative), Dr. Hertle gave us his opinion.  

The Results

He believes that Jesse has a null point up resulting in a downward head tilt of about 15-20 degrees.  He believes he only uses the head tilt when he is in a new or novel environment and he is trying to visually capture everything.  Dr. Hertle believes that Jesse has some mild nearsightedness which doesn't require glasses at the moment, but may in the future.  Apparently 80% of kids with nystagmus need glasses at some point.  He also believes that he has mild ocular albinism.  

A Possible Cause

He also believes that Jesse's nystagmus is caused by some developmental disturbance of the visual system in utero.  When in utero, the enzyme system that makes pigment and give our eyes their color, helps guide and develope the retna, optic nerve, and fovia.  After birth it produces pigment.  If it functions well in utero but doesn't function after birth you get the blond hair blue eyed race.  If it doesn't function well in utero you get visual problems and nystagmus.  In Jesse's case, it most likely didn't function well in utero and didn't function after birth: nystagmus & blond hair/blue eyes.  Dr. Hertle believes this led to a slightly underdeveloped retna and lightened optic nerve -- mild albinism.  About 65% of the operations on patients with albinism have a head down tilt.
He believes that Jesse's nystagmus is caused by a X linked dominant trait from Shelley.  An X linked dominant trait is expressed differently in every child.  He believes that for some reason the X linked dominant gene didn't present itself in Max the way it did in Jesse.  Because they are boys, it's 50/50 that if this is caused by an X linked dominant gene they would have presented with nystagmus.  If they were girls, they would have another X from dad and would not have nysagmus because they would use the good copy of the gene.  This is the rarest form of albinism.  

Why X linked dominance instead of recessive or other?  Becuase Max has the blond hair and blue eyes but no nystagmus.  Recessive genes tend to show very consistent traits from child to child, where dominant genes are not.  It wouldn't be X dominant from Jeremy because he gave the Y chromosome.  

Dr. Hertle did say that Jesse's fovia and macula look good, and the pigment in the fovia area looks good which goes along with good visual potential.  Phew.  

Going Forward & Possible Surgery

In his crystal ball, he can't tell us what his vision will be in terms of numbers.  He does say that his eyes will probably not handicap him.  Nystagmus will guide his life a little bit, but it won't hold him back.  Most of the kids with postures (head tilt) at this age will have vision good enough to drive.  He will play sports and have friends.  His education and learning won't be inhibited by the nystagmus but he may need minimal 

Having said that, he thinks he would benefit from treatment (surgery).  He doesn't want him to have to make a choice with his vision.  His visual system is not static.  It's dynamic based on his mood, environment, and time.  The world looks different all the time.  So he tries to gain his best vision by putting his eyes where the nystagmus is the least (chin down).  When he doesn't care that much, he won't posture his head but when he does care, he will posture.  The reason for the treatment, muscle surgery, is to give him the best vision straight ahead (primary) all the time so he doesn't have to make a choice between best vision and posture.  This will become more important as he grows older and starts studying more and learning more in school where he has to concentrate.

The surgery (standard eye muscle surgery - procedure #2 as he calls it) will change the nystagmus and not only bring his null point up to primary (straight ahead) but also expand their best visual field from a cone to a balloon.  That is, larger field of good vision in addition to posture.  It's possible that the surgery won't make the posture go away completely, but it would greatly help.  For this surgery an incision made on white part of the eye and muscles are cut and reattached - He operates on three muscles - the oblique, lateral rectus, and superior rectus.  Operation #2 is three muscles on each eye - recess the superior rectus, myectomize (a piece out of this muscle) the inferior oblique, and tenitomize with reattach (remove and reattach) of the lateral.  

The operation is out patient and takes about 30 minutes.  

Side Effects

Side effects: 10-20% of the kids that have muscle surgery to treat nystagmus need a second surgery to correct a new null point, lazy eye, or some other condition that could develop within a few months or even years later.  Because Dr. Hertle does about 10-12 eye muscle surgeries a week, this is about 1-2 children.
Final Results & Choices

So we will get the quantitative results from the ERP and the VEP in a week or so, but they will probably just confirm what Dr. Hertle believes right now.  

Now we have a choice.  Should we do something and if so, when.  Dr. Hertle believes the risk of doing something is less than the risk of doing nothing and the best effect would be when they are younger.  But of course it's easier when you're removed.  As Jesse's mom and dad this is a huge decision for us.  

I think we've always believed that we would always have surgery for Jesse, but now that time is approaching it's such a difficult decision.  For me having confirmation of his head tilt, and really noticing it as he was trying to concentrate on the screen during the VEP makes me feel that the surgery will help him and it gives me confirmation that he will need correction someday to have the best possible outcome in school and in life.  However, is that time now?  I know if we do it now then 6 months, a year, three years from now this will just be a blip on the radar.  But what if something bad happens.  What if he's in that 20% that needs a second surgery.  What if something goes wrong and his vision gets worse?  He's such a happy go lucky boy, I can't imagine doing anything to him that could change that.   

Decisions, decisions.

Then of course there's the question if we wait and go with Dr. Lingua's procedure.

If you haven't been following with our journey, click HERE to start from the beginning.  

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