One Year Activation Anniversary

Yikes! I've been neglecting this blog! I have a few minutes to scribble a bit.

One year ago today my CI was activated. And it has been nearly 8 months since my last post here. My CI hearing has changed and improved significantly since then. Everything is better. Pitch sounds almost normal, music sounds like music, voices are voices. I function almost like a normal hearing person. Only very noisy situations can put me at a disadvantage, but it is still much better than I was doing with hearing aids. I never dreamed that a CI could sound as good as it does.

I haven't need much adjustment to my CI in a long time. My last mapping was in May. I am now using mostly a single setting for all situations:

• IDR (Input Dynamic Range) 75
• Hi-Res-S w/F-120
• 50/50 T-Mic/Built-in Mic

I sometimes switch to 100% T-Mic in windy or very noisy situations. The IDR of 75 is at almost the max of 80. I tried 80 and noticed a little too much background electronic noise. It took a while to get used to running at 75, after using 60, because there is more low-level environmental sounds coming in, so it seems noisier. But I soon noticed a definite improvement in speech discrimination -- even in noise. Plus, I like hearing everything now. Even the scritchy scratchy tickety tick sound of a hard drive in a computer, ticking clocks, and all sorts of everyday sounds.

I stopped using my hearing aid in my right ear way back in April. At first because it stopped working. And then I noticed I liked not dealing with the higher frequency pitch mismatch between the two sides. It was like a tug-of-war. Now, without the hearing aid, my right ear just fills in the low frequencies that are missing from the CI quite well. I will probably get my hearing aid repaired next year and give it a try again now that my CI ear and brain have mostly normalized the pitch. I suspect that if I can get them working good together it might help picking voices out of noise.

My CI center closed over the summer (due to the surgeon suffering a severe injury that sadly ended his surgical career), so I requested my medical records. One interesting thing I learned was that I was implanted with the straight array (1j), not the pre-curved array (helix). I thought I was going to get the helix, so I don't know why the straight array was used. In fact, I didn't even know it was an option at the time I was making the choice of CI -- I thought Advanced Bionics had switched to the curved array. Odd, but I'm not complaining, especially considering my outcome.

The T-Mic on my CI failed a couple of weeks ago. Because I use a 50/50 setting, I didn't know what was wrong at first because the other mic was still working. Things just sounded different, and the phone sounded really weak. Once it dawned on me what was wrong, and confirmed by switching to a 100% T-Mic setting and getting nothing, I swapped in my backup T-Mic and all was well again. Fortunately I was just under the 1-year warranty cut-off, so AB shipped me a replacement at no charge.

Back to the grind!

CI 2008 Conference

The 10th International Conference on Cochlear Implants and other Implantable Technologies wrapped up this past weekend in San Diego. Four days of scientific presentations, vendor exhibits, corporate meetings and networking. Held every other year in locations around the world, it is a way for surgeons, audiologists, researchers and others to present new findings, continue their education, and find out what the heck is going on behind the scenes in the CI world these days. The four CI manufacturers -- Advanced Bionics, Cochlear, Med El and Neurelec -- sponsored the conference and had large booths in the exhibit hall. Since this year's conference was held practically in my backyard, I could not pass up such a great opportunity.

The conference was not solely about cochlear implants, it also covered various other auditory implants such as brainstem and bone-anchored implants, but I will only be covering the CI related parts. With over 230 presentations roughly ten minutes each in length it was necessary to have up to three concurrent sessions running at a given time -- making it impossible to catch everything. Fortunately it was well organized and I only missed a couple of presentations of interest due to conflicts. There were also over 250 poster presentations in the exhibit hall. I was able to talk to reps from all the major CI companies, posed questions to several of the researchers, and met some really interesting individuals. Four days of MSO (Maximum Sensory Overload) from which I am still attempting to recover!

The topics in which I was most interested were:

• Basic Research
• Electrophysiology
• Coding Strategies/Electrode Design/Mapping Strategies
• Music Perception
  

The presentations in those topics fell into a few general categories:

• Tests of relatively newly released technologies (e.g. Fidelity 120)
• Analyzing current technologies, looking for areas needing improvement
• Tests of new technologies in development
  

I intend to write more in-depth posts about several of the areas that I found most interesting. For now I will give a quick overview. If you want me to expand on anything below, let me know in comments and I will try to push that to the top of my list.

Most of the scientific studies presented were specific to a particular brand, however a few were multi-brand. All the brands are performing well with no huge differences.

As CI performance has improved, the need for better tests has increased. Some of the easiest tests are starting to see a ceiling effect, in which a significant number of subjects score at or near 100%. While that can be quite satisfying on a personal level, it does not provide useful information when testing existing or new strategies. Other tests don't adequately reflect real-world performance. Many new test methods were proposed and some should work their way into the mainstream in the coming years. So, CI users, be prepared for more challenging tests.

There were a couple of presentations regarding tracking implant reliability. Apparently there are differences between manufacturer's definitions of device failure as well as their reporting methods. Some effort is being put forth to globally standardize CSR (Cumulative Survival Rate) reporting.

Now that Advanced Bionics' Fidelity-120 strategy has been commercially available for over a year, as one would expect it was the subject of quite a few studies. There is some indication that speech recognition in noise, and overall speech discrimination in tonal languages, is improved to a degree using F-120. Studies of music perception were a bit of a conundrum: while there was no significant improvement in objective music testing scores (melody, timbre and rhythm identification), subjective scores for music enjoyment were significantly higher across the board.

Spread of Excitation (SOE) was a hot topic. SOE is the longitudinal spread of electrical energy across the cochlea. SOE can be measured using the return telemetry from the CI, which takes readings from electrodes on either side of a fired electrode (or electrode group). Several studies indicate that narrower SOE correlates with improved speech and pitch discrimination performance. Another study suggests that SOE narrows over time after implantation, which could be one factor why most CI recipients' performance improves over time.

There is also work going on to create stimulation strategies that reduce SOE by applying reverse-phase stimulation to adjacent electrodes. The goal is to improve tonal quality, which could benefit both music and speech perception.

I was glad to find several studies in progress on pitch alignment and mapping. One study used a 3D model of the cochlea and electrode position created from CT Scans to estimate the overall pitch alignment. Another used patient-controlled software to subjectively adjust their map. There is indication of improved speech understanding with a custom fit pitch map.

The prior two subjects are the BIG TWO for me: Pitch Map and Tone Quality. I think they go hand-in-hand. Even though my pitch perception has improved over the four months I have been activated, it has a long way to go and I doubt it will get there on its own. I am looking forward to the day I can sit down at a mapping session and realign my pitch map so that intervals and octaves are accurate. Having improved tone quality should not only help perform that process, it should improve the overall sound quality of the final result.


I was encouraged by the variety and volume of research being conducted to improve CIs. I was also glad to have the opportunity to provide encouragement to a couple of researchers working on my Big 2. And my CI performed like a dream. For the past 10 years or so, before my CI, I would have had a great deal of trouble communicating, and would have completely depended on the captioning (CART system) that was provided during presentations. It was liberating to actually watch a speaker and glance at their presentation graphics, rather than paying most attention to a caption screen. The most difficult listening situation of the conference was during the Karaoke sessions at the Med El booth in the exhibit hall at lunch breaks. They really cranked the volume -- but at least it was (somewhat perversely) entertaining!


If you are interested in reading abstracts from the presentations, there is a PDF file of the conference program book available on the CI 2008 website.

The 11th conference will be held June-July 2010 in Stockholm, Sweden, with the 12th in Baltimore, Maryland in April 2012. Go if you can.

CI Research

CI Research Study

Shortly after my January 17 blog post I was contacted by some folks involved in CI research. It seems my interest at comparing and gauging my pitch offset between CI-ear and normal ear, and my experienced attention to sonic detail, could be handy in a research setting. I was asked to be a test subject and I complied like a good Borg. Within a week we had scheduled a one-day trip to the Cochlear Implant Laboratory at Arizona State University.

On the day in mid-February, I had a 6:30 am flight out. So it was up at 4:00; to the airport about 5:00; hit the security area about 5:15 – my first time through with a CI. I had brought along my spare processor and I remembered reading that it should not be x-rayed (something about x-rays damaging the microphone element). After filling 4 trays with shoes, belt, pocket contents, laptop, and other contents from my bag, I pulled out the spare processor and flagged a TSA person. Upon explaining the x-ray issue, and showing my handy little CI card provided by Advanced Bionics, I was rewarded with a trip to secondary inspection so my processor could be tested for explosive residue. It only took a moment and the TSA people were friendly. I quickly re-robed and repacked and headed up to the departure area.

I located the gate for my flight and slid into a nearby seat. Most people were deep in their laptops, cell phones or mp3 players, so I felt a little the Luddite cracking open a hardback book. I mostly read, but also spent some time listening to PA announcements and even did a little eavesdropping – both of which were surprisingly successful with my decidedly non-Luddite CI.

At about 6:15 we got the call to board. It was a sold-out flight, but even with that we were ready to go on-time; something else wasn’t however so we were held on the ground for another half-hour. The pilot explained something about the delay but the crappy quality of the aircraft’s intercom put the answer just out of my reach. I could have asked my seat-mate, but that would have opened the door to an entire flight of conversation and I had reading to do; plus old hard-of-hearing anti-social habits die hard. The pilot made up some time in the air and we touched down only about 20 minutes late. I grabbed a cab and was deposited at ASU a bit after 9:00.

The CI Lab is in a shiny new building at the edge of the campus. I made my way up to the lab and was greeted in the corridor by Dr. Michael Dorman, the head of the lab. We stepped into his office and began chatting about CI’s. Dr. Dorman has been involved in CI research for quite a long time. While I was digging up CI research articles over the past few months I ran across many on which he was co-author. Soon we were joined by Dr. Tony Spahr, who would be directing my activities for the day. The nut of the conversation was that research often is full of promising ideas that go nowhere; occasional lines that lead to minor improvements; and the rare find that can be significant. ASU and Advanced Bionics are in the process of studying some new techniques to learn if they warrant testing in a full stimulation strategy and can ultimately be implemented with a software upgrade.

The focus of the current study is testing the effects of different electrical stimulation patterns on tonal quality. It is hoped that developing full processing strategies that deliver purer tones will improve overall perceived sound quality, aiding both speech discrimination and music appreciation. But the first step is finding a way to improve individual tones.

Most current CI strategies deliver sound to the cochlea as sequential pulses, hundreds to thousands of times per second. For a complex source sound, most of the electrode contact points on the array will be fired to convey pieces of the entire range of frequencies in the source. When a CI user listens to a pure tone, such as a tuning fork or sine wave tone, the pulse output goes to a small group of electrodes sequentially, with the center of the group at the highest amplitude (loudness). In lab testing, a single electrode can be pulsed. In either case, the sound perceived is not a pure tone – it is accompanied to a degree by the noise and distortion of unwanted frequencies on either side of the actual tone. It can be described as slightly fuzzy or buzzy. This may be, at least partially, due to the fatness of the electrical stimulation pattern of each pulse delivered to the cochlea affecting an area larger than the target. Speech is made up of relatively noisy components, so the effect on basic speech discrimination is likely not large. Where it may make a difference is in more difficult listening situations such as noisy environments. But the tonal quality of speech – its timbre – and of course the quality of music should improve with a more accurate tonal representation.

Most of my day at the lab was spent repeating a series of tone quality rating tests, the balance undergoing standard audiology tests for my test subject record. For the tone quality tests Dr. Spahr set me up at a test station comprised of a laptop, interface box and headpiece. A software application ran test routines which issued pure tones delivered by both standard and experimental electrical stimulation patterns. My job was to click a button to play a tone and then enter a value from 0 to 10 as a rating (0 – noise, 10 – pure tone). This would repeat about 40 to 50 times, usually randomizing 4 to 6 different tone/strategy combinations. At first it was hard to establish a reference point for myself, and judge the range of quality between various tones, but after a few times through it got easier. It was a blind test of course – I had no idea what method was used for any particular tone – but I was often detecting a fairly significant difference. On average I was rating the best as an 8, the worst as a 6. Some tone sequences the difference was more noticeable, some less. The largest spread in any test was 5 to 9, the least 7 to 8. For me, a 9 was very close to a pure tone, a 5 was a quite fuzzy tone.

At the end of the day I learned that my tone quality rating test results reinforced findings with other test subjects, and that the tones I was rating highly were the result of some of the new strategies being studied. There is no guarantee it will work well in a full sound processing strategy, but even so it is very encouraging. I was glad to be of help and spend time with individuals that are working to improve the technology I now enjoy. It was a pleasure meeting and working with them.

Research Conference

The 10^th International Conference on Cochlear Implants and Other Implantable Auditory Technologies will be held in San Diego in early April. Dr. Spahr is scheduled to give a presentation, “Perception of monopolar & tripolar stimulation by cochlear implant listeners.” The Agenda page on the website has a full listing of presentations – and there are a lot. It is an interesting window into the breadth of ongoing CI research.

A note on CI Brands

I think it is important to point out that this research is specific to the Advanced Bionics CII and HiRes90k implants. At least some of the strategies under study depend on the capability to fire multiple electrodes simultaneously, which is possible since these specific implants have an individual independent output circuit for each of 16 electrodes.

Every CI candidate has to decide what brand of implant to get. In the U.S. we have 3 choices: Advanced Bionics, Cochlear, and Med-El. It can be a difficult decision because there are many things to consider: technology; reliability; surgeon and audiologist available familiar with the brand; upgradeability, etc. But when it comes to the sound quality there is no way to do a comparison, one has to make that part of the choice on anecdotal information on blogs and other resources. And it seems everyone’s ears are different in how well they accept and function with a CI. Fortunately, all the brands seem to provide a similar level of performance. So with current publicly available stimulation strategies most users would likely be happy with any choice. However, when considering advances that might be coming, choosing the Advanced Bionics implant leaves the door open to more options. The Cochlear brand has a very good record of maintaining compatibility between their implants and upgrades to the external processor, but the implant has only a single output circuit that does not allow for simultaneous electrode firing. While this does not rule out improved stimulation strategies based on new sequential electrode firing techniques, it does rule out the use of any new strategies that require simultaneous electrode firing. The un-tapped potential of the Advanced Bionics implant is one of the main reasons why I chose it.

3 Months Post Surgery

I know I have been a little quiet here lately. Partly because I have been busy enjoying my new ear, and getting back to projects sidelined by recovering from surgery; but mostly because I am working on a blog post regarding a CI research study I recently entered and I want to take the time to get it right. However, that's taking longer than I expected and I think I should mark my 3 months since surgery with an update.


Last time I wrote about post-surgery issues was at the 1 month point. The main things were minor aching at the implant site; possible Eustachian Tube drainage; taste disturbance; occasional slight fullness in ear and slight vertigo. The only one remaining now is taste disturbance. Otherwise I feel great.

This taste disturbance -- and I think disturbance is good term for it -- is quite odd. In the first few weeks after surgery I am quite sure now that what I perceived as drainage from my Eustachian Tube was in fact the result of this issue. Most of the tingly numbness is gone, but I have a constant taste sensation at the back left side of my tongue. It is a combination of sweet and salty. Fortunately it is not overpowering and it does not make food taste awful, just off. I can alleviate it quite a bit by chewing on the opposite side. If I were a chef I think I would feel impaired, but for me it's just a minor nuisance.


I had my 5th mapping a couple of weeks ago. I only needed some minor tweaking to balance things out. We also loaded up some test programs on my spare processor. One with a wider IDR and another with wider pulse width. I haven't had a chance to test them thoroughly, so I have nothing to report yet.

My CI hearing continues to change and improve, though more subtly than the first couple of months. I will cover that in more detail in my next post.

Mapping No. 4

A couple of days ago I had my 4th mapping appointment, 5 weeks to the day after activation. In the 2 weeks since my last appointment I had steadily increased the volume level to nearly the 3 o'clock position on the dial, so it was time for more adjustments.

The first thing my audiologist did was stick me in the booth for some sentence and tone tests. The last time I had that done was for my CI candidacy screening back in October. For many years the sentence test has been a futile and mildly frustrating event. If you are normal hearing and want a simulation, try stuffing some good ear plugs in your ears, set your clock radio to a talk program, put a pillow over it and try to repeat what you hear. The sentence test is a pre-recorded male voice, calibrated to a normal conversational level, speaking random sentences such as, "the two boys played in the rain," or "she put her purse on the table." Sitting in the booth waiting for the test to start, I was subconsciously gearing up for the usual strain when a man said quite clearly something like, "the boy threw the baseball through the window." I easily repeated it. This went on for several minutes. I guessed on a couple of words, and only missed one sentence completely (in which, as my audiologist explained later, the speaker had practically yelled something about "the angry man..."). Four separate tests were run. My scores ranged from 93% to 100%. Amazing. And that was with my old map. Sure, it was in a quiet setting with no background noise to interfere, but I only scored 13% before my CI!

Next up was a tone test. I didn't get a hard copy of the test results but I took a quick look at it. At the lower frequencies, which we kept lower at my last mapping, my threshold was in the 40 dB to 35 dB range. Then it dropped to 20 dB at 2 kHz before climbing a bit to 25 dB at 4 kHz. A 20 dB or lower threshold is considered normal hearing, so I'm doing great. And, again, that was with my old map.

A quick shuffling of cables and I was connected to the Advanced Bionics laptop for a mapping. We decided to keep the same 3 program strategies and just crank the levels. We ended up boosting the low frequencies a bit more relative to the highs on my HiRes-S programs, so I think my tone test would be flatter now. One thing I noticed more than during previous mappings was the distinct difference in the quality of sound when Fidelity-120 is ON or OFF (F-120 is AB's new feature that increases the number of spectral bands dramatically). When F-120 is OFF, my audiologist's voice has a slight "buzziness" to it; when ON it is smoother, more natural.

We finished up the session with a discussion about my right ear hearing-aid and HiRes-P vs. HiRes-S (two different electrode stimulation strategies). She gave me the green light to use the hearing-aid as often as I want. So far I've been liking HiRes-S better, for speech especially, but I still want to spend some time testing HiRes-P. I was listening to some music a few days ago, switching between P and S, and I think P might be better. Also, there is the chance that, once I get more accustomed to the CI, P might be better for everything -- so I don't want to discard it from my available programs.


The number I mentioned in my prior post was... hold on to your hat, or grab your underwear, or something... the total billed cost of my CI, surgery and activation. Sobering, huh? It deserves to be on a t-shirt, or a tattoo. I keep getting things in the mail detailing the breakdowns of all this and each time I hold my breath because they look like bills. Though I was covered under a top-tier HMO and I'm quite sure we only pay a small co-pay, it's still enough to give one the willies. I feel fortunate to have received this magnificent technology, but I also feel very fortunate that I didn't need to take out a second mortgage to pay for it.

1 Month Post Activation

A few weeks ago, on Jan 2nd, I had my 3rd mapping appointment. It wasn't really a "mapping" since we didn't adjust anything. I had gone a bit overboard on the levels at mapping #2 and had only just reached the point of running the volume at normal. My audiologist used the time to run the NRI (Neural Response Imaging), which I described in my "Mapping No. 2" post. During the NRI the software sent pulses to various electrodes in a rhythmic pattern. It sounded like wooden blocks clacking together, almost musical. I enjoyed it. She said the results were good and she would use them as a reference at my next mapping. She also removed the extra half-strength magnet from the head-piece because she felt it was grabbing on a little too strongly. It seemed to adhere fine with just the normal magnet.

Unfortunately, in the following days it became clear I wasn't quite ready for the reduced magnet strength. The head-piece would fall off too easy, just by sitting down or doing anything that slightly jarred my head. Worse, it would constantly lose the communication connection and have to re-sync -- several times per hour at least. It started to drive me nuts! My CI has a very distinctive sound when it re-syncs. First it goes instantly dead. Then, upon reconnecting after about a half second, it makes a deep, metallic, watery, reverberating "PINNNNGGGGGG" that sounds exactly like a sonar ping in an old World War II movie! Finally after another half-second the sound of the world comes rushing back. Normally it's not bothersome at all, but having it happen every 10 minutes or so I felt like I was under attack!


The following week, on Jan 8th, I had my 5 week checkup with my surgeon. He checked my scar, the site over my implant, and took a quick peek in my ear. All looked good. I told him about the head-piece. He checked it and said there would be no problem putting the additional half-strength magnet back in for awhile, as long as we keep an eye on it. It is very important to use as little magnet strength as possible. There is the potential to irritate the skin over the implant if it squeezes too tightly. If allowed to go on too long it can lead to an ulcer, which would mean not wearing the CI for the time it takes to heal, or worse it could become infected which puts the implant at risk. There have been cases in which the implant must be temporarily removed to allow an infection to clear up. He said the skin over the over the magnet toughens up with time and becomes less prone to problems.

Next we had a good little discussion about the pitch perception I have described in prior posts -- in brief, everything sounds deeper in pitch then I expect and in relation to my right ear. He was intrigued by my tests that showed about a half-octave difference the week after activation. I wondered if it had to do with insertion depth and he said it was quite likely related. He confirmed my suspicion that they have no way to precisely position the electrode array to match frequency location, adding that there is evidence pitch perception is not necessarily "hard-wired" to locations in the cochlea and that the brain may compensate over time. I think I might already be experiencing some re-wiring, since some sounds don't seem as deep as they did a month ago.

Finally we discussed my right ear hearing aid. He asked if I had been using it at all. I told him my audiologist had recommended I not use it very much during the first month or so, but that I had tried it for short periods of time on occasion. He explained that in the past they (CI surgeons) had found most users didn't want to bother with a hearing aid in the other ear because the CI sounded better by itself, or the two didn't sound good together. So they didn't encourage continued usage. But now they have made a one-eighty since there have been findings that using a hearing-aid along with a CI has several advantages if the unimplanted ear still has usable hearing. It helps with spatial location, speech discrimination, and pulling sounds from noise. And by keeping the ear functioning as much as possible it can improve the result of a future bilateral implant. I had intended to work at using my hearing-aid again, so it was great to get encouragement from my surgeon.


I like movies. Who doesn't? For the past 5 years, I have always gone to a theater with closed-captions. This severely limits one's options since there are only a couple of captioned screens locally. Once or twice during that time I went to a non-captioned theater and I couldn't understand a word. Last week my wife and I went to see "The Golden Compass" in a theater without closed-captions. Even though I've been doing really well with speech, I had no idea what to expect with a loud movie soundtrack. By the end of the endless previews my hopes were rising. Ten minutes into the movie I practically had to scrape my jaw off the floor. I was getting nearly every word, without straining. I even did some little tests switching between hearing-aid only (loud, noisy, english-as-a-foreign-language), CI only (great!), and both (slightly better!!). My best guess is that I caught about 80% of the dialog, if not more. I never felt like I missed anything crucial. The special effects and music sounded good too. Even though the movie was disappointing I was pretty thrilled.


I was in the shower the other day, cleaning my ears, and I noticed a sound when I wiggled my wet finger in my implanted ear! What? More wiggling and sure enough I heard a deep sounding flutter in my left ear. So I seem to have a little residual low frequency hearing. I will have to run some tests on that in the near future.


I have a big project going on in our little (tiny) front yard. I started it many, many months ago and had to take about 2 months off because of my medical adventures. I am finally back to work on it! It feels really good to be physically active -- and sore in the morning -- again. The sound of a shovel digging into wet decomposed granite is just lovely, "Crrrruuuuuunchhhhhh!"


As a parting gift -- ponder this number: 134861.10