Acoustic neuroma and diving . . .

[NancyLynn]

I've been having unilateral high frequency hearing loss and tinnitus, and decided it would be a good thing to get it checked out in advance of my dive trip to in two weeks - just on the off chance it was something other than my age catching up with me.

It's always a bad thing when the doctor comes into the room looking very interested in you . . . unfortunately something I recognized because I've had far too much experience with it.

I've been cleared for the upcoming dive trip, after being duly cautioned that since I have documented hearing loss in one ear that I should avoid any additional barotrauma (the "you only have one kidney left, make sure you protect the other" kind of speech).

I am, however, being evaluated for "a growth," which my post visit research tells me is an acoustic neuroma. As near as I can tell, my risk level of having one is somewhere around 30% (both unilateral tinnitus and high frequency hearing loss. I lack the objective third symptom that would put me in Welling's high risk category - 30% decrease in ability to repeat single syllable words - but I have long known that I don't process sounds as well in that ear. I hear all of the sounds and have to stop and think what they mean - as opposed to the instant association that occurs in the other ear - so I can't effectively use anything that makes the affected ear the sole input for words (like the phone)).

An ABR is scheduled for Monday. I will probably press for an MRI, even if the ABR shows no different transmission time relative to the different ears, based on my subjective additional symptoms and my understanding that small tumors are most likely to create false negatives - and also most likely to be treatable without sacrificing hearing. (Everyone seems to agree that MRI is a more effective diagnostic tool - the disagreement seems to be whether it is cost effective to use MRI for everyone in the intermediate risk category - based on the cost of using MRI on 90-95+ people to discover additional 5-10 tumors.)

Anyway - looking down the road - post surgery (IF that is what I have and IF the treatment is surgical removal) any experience/advice regarding subsequent diving? I found one article on DAN that suggests this will end my diving, but the explanation didn't seem to me to be based on necessarily universal consequences of the surgery.

(For anyone concerned that I am obsessing about possibilities - you are correct, I am. Over the years, through a number of "freak" medical conditions I, or a family member, have had I have learned that it is the best way for me to cope. Knowledge of long term possibilities both helps me prepare - and if it is the "worst," I am better able to actively participate in my medical care because I am usually able to anticipate and ask informed questions about - or make suggestions about - whatever the doctor recommends. The better doctors appreciate it and quickly actively involve me in the decision making tree. It does, however, tend to freak out insecure and sometimes younger doctors - and watching the freakout is a nice distraction. )

 

[CheddarChick]

Ahhh Nancy...man what a sour note to hear right before you go diving.. Make the best of your time there and don't worry about the what if's...

 

[NancyLynn]

It reinforces my decision to go diving and enjoy myself.

When I got the flyer for the trip I misread the date and was thinking it was a year from now (which would have been much more convenient - daughter would be off at college, my time intensive work load would have passed, spouse would be done with PhD qualifying exams). When I realized my mistake, I debated with myself, but ultimately decided to go anyway. Now, I'm really glad I didn't postpone it. Having this kind of scare, regardless of how it turns out, reinforces the reality that none of us know how long we will be able bodied/able minded/alive - and we ought not waste what time we have on things that ultimately don't matter.

As to worrying about the "what ifs," I know some people function better with small, easily digestible chunks of information. I function better with the whole buffet table in front of me - so I'm in the process of filling the table up. If I know this will likely be my last chunk of diving (and I hope to know by then), I will savor it that much more.

 

[NancyLynn]

No news, so far. ABR was negative - so that makes it almost certain that there is no large tumor. That test apparently isn't as refined at finding small ones - so heading for a neurological poke and prod (I hope - ENT sent me back to primary care for referral - which may or may not meet with insurance pushback).

 

[TSandM]

Well, at least you have good news so far. Hopefully, your insurance will cover the MRI.

 

[NancyLynn]

Well, at least you have good news so far. Hopefully, your insurance will cover the MRI.

That will be the next battle - at least there isn't any big rush to fight it, since IF there is anything there it is small enough not to be showing up on the ABR (and these critters are notoriously slow growing).

Even if insurance won't pay for it, I may decide my peace of mind is worth enough to pay for it on my own. We have accumulated quite a family history of missed diagnoses and oddball conditions - kinda makes me paranoid about not following every reasonable diagnostic path.

In the mean time - I'm going diving!

 

[shakeybrainsurgeon]

If you have to pay for it on your own, check out the cost of a CT scan with IAC (internal auditory canal) views...it might be as good for acoustics as MRI and cheaper (and faster too). I can't guarantee it will be chepaer, since I haven't personally checked the costs recently, but CT is usually less expensive than MRI.

If they are concerned about acoustic tumor, why waste money on ABR testing? Imaging is the only sure way and, if acoustic neuroma is suggested clinically and your insurance company won't pay for an MRI to rule it out, either a) your health insurance is terrible or b) the clinicians have done a lousy job of convincing them to pay for it.

If you have significant preserved hearing in the ear, the likelihood of any tumor is small, certainly it is unlikely to be a large tumor (> 1 cm). The typical acoustic tumor patient is nearly deaf in the ear before it is diagnosed. Even if you have a tumor, provided it is small, it can be treated by gamma knife radiosurgery (a one-time, computer-contoured blast of cobalt radiotherapy done as an outpatient) which requires no true operation and would not preclude diving. Do not opt for open surgery for a small tumor, but demand evaluation by a radiosurgery specialist. A normal ABR almost guarantees that if a tumor is present, it is small enough to be treated with radiotherapy.

If a tumor is large and requires surgery, go to a neurosurgeon and have it removed by a retromastoid transcranial approach if you want to dive. Do not have an ENT surgeon take it out through a translabryinthine approach which may preclude diving again. Of course, I am biased, having done them through the transcranial approach. A transcranial approach is no guarantee that diving will be safe, since the inner ear's integrity can be disrupted even by this method, but it is generally less harmful to the ear. (ENT people point out that the transcranial approach is riskier for the BRAIN, but, hey, you have to break eggs to make an omelet).

The bottom line: you will hopefully have nothing seriously wrong, but if an acoustic tumor is discovered, get multiple opinions about treatment...there are many ways to skin the cat, so to speak, some safer than others. Having an acoustic tumor should, in most people, NOT preclude diving, even if it requires treatment. And they are virtually always benign and slow growing (about 1 mm in diameter/year on average) so no urgent decisions about imaging or therapy are needed.

Good luck.

 

[rwmaloney]

I used to do this type of evaluation and surgery. My advice get the MRI with contrast before you dive. Ther are 10-30% false negatives with BSERA, With acoustic neuroma you have increased chance of a perilymphatic fiftula. If you have a neuroma and it is paraaxial, pressure dynamics during diving can disrupt blood flow through the anterior inferior cebellar artery. That is inconsistent with survival.
Statically you probably only have unilateral neurosensory hearing loss or subclinical Menieres disease. A CT scan can deterimine if you are at risk for perilymphatic fistula looking at the cochlear aqueduct. Electrocochleography can identify Menieres befoer it becomes a problem with balance.

 

[NancyLynn]

Thanks - what you've said matches most of what I have found on my own.

If they are concerned about acoustic tumor, why waste money on ABR testing?

ENT's training is that referral for an MRI requires positive ABR + unilateral hearing loss and tinnitus when word discrimination difficulties on that same side are only subjective (the processing time is just enough longer in the right ear to translate the sounds into words that it isn't effective for me to use that ear for interactive communication (like on the phone), but since the test doesn't take into account processing time I can repeat the single syllable words they ask me to repeat). My research says that his practice is one of two trains of thought - yours being the second.

Even if you have a tumor, provided it is small, it can be treated by gamma knife radiosurgery (a one-time, computer-contoured blast of cobalt radiotherapy done as an outpatient) which requires no true operation and would not preclude diving. Do not opt for open surgery for a small tumor, but demand evaluation by a radiosurgery specialist. A normal ABR almost guarantees that if a tumor is present, it is small enough to be treated with radiotherapy.

This information is particularly helpful - what I found about its usefulness seemed mixed. Intuitively, it seemed like it should be better option, as a starting point at least. Less invasive, and since the tumors seem to be slow growing anyway surgery would always be an option later on if the radiosurgery didn't halt the growth or shrink the tumor. Glad to have confirmation that it is a good option.

Do not have an ENT surgeon take it out through a translabryinthine approach which may preclude diving again.

He won't. He is very good at referring when the treatment pushes the limits of his training. He got my spouse to a surgeon who could use state of the art techniques to correct a completely blocked right sinus. Virtually no pain and minimal recovery time - compared to everyone else we have talked with who had the same surgery.

The bottom line: you will hopefully have nothing seriously wrong

Me too, but I would rather know and get treatment early if there is something going on.

but if an acoustic tumor is discovered, get multiple opinions about treatment

If it turns out to be something that requires treatment, would you mind if I PM you to see if you have any information about who is good locally? (I appreciate your participation here - so don't want to push for more of your professional expertise than you are willing to give during your free time.)

 

[NancyLynn]

Finally done with all the tests, including an MRI - no acoustic neuroma!

Follow-up in 6 months, but unless progression of hearing loss is abnormal it just gets racked up as cause unknown. Guess one ear is just older than the other