Avalon's Army of Angels
|August 25, 2008
The Good, the Better, and the Slightly Perturbed
Today was a pivotal day at our house. Today, Avalon saw Dr. Benes, her
neuro-ophthalmologist. Today, we finally got some good news.
Dr. Benes does four things to check Avalon's vision. I'll break them down as they happened
1) We check for acuity with a normal eye chart like anyone else.
Avalon showed 20/25 today. That's an improvement from an earlier appointment. Its
not the best she's been, but its good.
2) She checked peripheral vision.
This is the area that's been affected the most by the high intracranial pressure. At the
worst, Avalon had lost nearly 70% of her peripheral vision. A doctor younger, or less
skilled than Dr. Benes might have misjudged Avalon all these years. You see, most
ophthalmologists have long since switched to the fully automated peripheral test.
Some of you may have taken one. Its where you rest your head on a small platform,
and look into a large white hemisphere. You are supposed to watch the small light in
the middle of the hemisphere, and sound a beeper when you think you see a
flashing light in your peripheral vision.
The stupid test gives me a headache every time. For Avalon, (or any child, I presume)
the automated test would be folly. There is no way of knowing if the subject is being
truthful and focusing directly at the center spot. Its not that Avalon would try to be
deceitful, its just its very tempting to look toward the light, giving a false positive.
Dr. Benes' answer to children doing the test, is to use an older version of the appartus,
a manual one. With the manual one, Dr. Benes can watch Avalon's eye through the
central hole. If Avalon looks away from the center, toward the light, Dr. Benes calls her
on it, and repeats the light stimulus later. That way, we know she's truly seeing/missing
the cue with her peripheral vision ~ not "cheating" by changing her focus. As Avalon
beeps, Dr. Benes marks the series of dots that Avalon has seen. When she's done,
she has creates a "map" of Avalon's peripheral vision, by connecting the dots seen, and
shading the areas that were missed.
Today, Avalon had regained a nice portion of her lower peripheral vision in one eye,
and reduced her blind spot in both eyes. In other words, progress. Good, positive
3) Avalon looks into a computer interface, and it takes a picture of her retina, and measures
This is the test I am least qualified to explain. I can see improvement/degradation
verses previous readings, but I'm not 100% sure what its measuring. I understand that
the computer program can overlay data from previous appointments for comparison -
but I truly cannot explain the science behind this. All I know, is that this is a purely
clinical test, no subjective elements that can be debated by anyone.
The test looked better for one eye, reasonably the same for the other. In fact, for
the eye that changed only a little, the data approximated what the eye had been after the
first shunt was installed in Jan of 2007. We know the pressure was still high then.
4) Dr. Benes ultrasounds Avalon's eye, to look at the diameter of the optic nerve
Some doctors argue the validity of this method being used to predict intracranial
pressure. (high pressure causes the optic nerve to dilate) Dr. Benes agrees that
research has not been done to directly correlate the diameter of the optic nerve to a
specific IC pressure. She uses it as a tool to compare diameters of the nerve
between different appointments with an individual patient. For example, we could see the
bubble of fluid that was forming from the extreme pressure before Avalon received her
first shunt. That very visible bubble, was the reason Avalon was scheduled for the
emergency Optic Nerve Sheath Fenstration surgery. The ONSF placed holes in the
covering of the optic nerve to allow excess fluid to leak out behind the eye, reducing
pressure on the critical last 4 mm of the optic nerve. We can still see fluid leaking
out those holes on current ultrasounds.
We learned today that the swelling is appreciably reduced in one eye, and slightly
reduced in the other.
*So what does all of this mean?
It means the temporal decompressions are doing their job. Dr. Benes said Dr. Kosnik was
brilliant for thinking of them. They're doing exactly what he hoped, they're buying us time.
By revisiting data from several previous appointments that we had known IC pressures we
could correlate with, Dr. Benes agrees with me, that we think the current VP shunt is only
barely functioning. Avalon's IC pressure was higher after the shunt was placed in May, than
it had been the month before. In addition, her vision had degraded along a predictable
curve that supports the notion that her pressure never reduced after surgery. In other
words, the VP shunt that was "flowing slowly" in the May 2008 operation, and "supposedly"
causing Avalon's high pressures, was doing a better job than the one she has now.
Therefore, Dr. Benes agrees that eventually, we need to have Dr. Kosnik do a shunt
revision on Avalon . HOWEVER, the temporal decompressions have been so successful,
we have time to wait for the revision.
You've heard the Good, and the Better. Now for the Slightly Perturbing. According to Dr.
Benes, the temporal decompressions have helped so much, that she thinks if we revise the
shunt to one that actually works...Avalon may actually have nearly normal pressure!!!!!!
Can you even imagine?! I seriously threatened to dance right there in the office. So, I'm
sure you're wondering what on earth is perturbing about that. The killer is, we can't go and
fix it right now. Dr. Benes agrees whole-heartedly with Dr. Kosnik - we need to WAIT.
Avalon's body and brain have been through too much this Summer, she can't take another
operation. She needs time, and lots of it, to thoroughly heal - so the next surgery can go
as smoothly as possible.
I know they're right. I know they have Avalon's best interest at heart. I really do. Its
just...we're sooooo close. Today, I saw hope and light. Today, I saw a chance to give
Avalon the best chance she's got at a normal life. Today...I saw the carrot...and I'm
croaking to grab it.
Normal pressure won't fix Avalon's nerve or bone issues. Normal pressure probably won't
fix her short term memory problems, or her motor control of her right hand. And Dr. Benes
was very sad to tell me, she doesn't think it will fix a large damaged spot on Avalon's one
optic nerve, she thinks this one area is just gone now... But all that's OK. That's all
potatoes. A normal intracranial pressure will help Avalon's brain heal, and will go a long
way toward keep her here. That's all we really care about.
I know Dr. Benes understood that. I could see it. But I also know she had to reign me in, its
the smart thing to do. So, before I left, we discussed exactly what I'm supposed to report to
Dr. Kosnik next week. I went over it several times to make sure I'm conveying precisely what
she wants me to. I know Dr. Benes was doing her best to be cautious...but even she gave
in to some pretty big grins. We couldn't help it. It was like catching that first glimpse of OZ,
and knowing its just a little farther.......