Thursday, October 25, 2007

Diagnosis

We went to have Nolan's hearing tested at a larger center, via a diagnostic ABR test. These tests are quite grueling, though not for the test itself. The baby has to be as motionless as possible, so they recommend you withhold food and sleep deprive the poor kid before testing. Trying to keep a hungry 2 month old awake on a 2 hour car ride is not a lot of fun!

We arrived at the center with our toddler in tow, to wait out the appointment with Daddy in the waiting room. The audiologist took Nolan and me into the testing room, and explained they had new ABR equipment. No sleeping necessary! It's a vivo-link ABR testing unit- they can even do ABR testing on toddlers as they play or watch a video. Incredible! Of course, I had just starved and sleep deprived Nolan for nothing, but at least I know for the future!

She tested the right ear and generated near-normal responses at 4000Hz. I breathed a sigh of relief. The testing continued, and when she wasn't quite done after an hour (still on the right ear), I started to think there might be a problem. She said he tested at 55dB at 500Hz, but they apply a correction factor and she called it a 40dB loss. He tested at about the same level at 1000 Hz.

She decided to run OAE (Otoacoustic Emissions testing) to check the function of the cochlea. This test sends sound to the cochlea and looks for an echo response. If it is there, the cochlea is intact. If it is absent, then the hair cells in the cochlea are damaged or missing. Nolan had no OAE's in the low and mid frequencies. They were present at high frequencies, but diminished. She expressed some concern that he might have a progressive loss, but we won't know until it, well, progresses!

The left ear tested nearly identical to the right. A reverse-slope in the mild-moderate range. A tympanogram revealed a healthy eardrum. She said he had mild to moderate sensironeural hearing loss and would need amplification. Unfortunately, she wanted to repeat the ABR (here we go for ABR number 7!) to verify the results. She also wants to keep a close eye on his responses in the high frequency ranges.

We ran from that appointment to the ENT, who gave us prescriptions for an EKG and urinalysis. Some hearing loss is associated with syndromes, so we have to begin ruling out each syndrome. She then took a look at Matthew and began talking to him. Matthew is big brother and is 22 months old, with a grand total of 3-4 words. When I explained he was speech delayed, she was flabbergasted (I daresay irate) that the pediatrician had not ordered a hearing test for him. I told the ENT that the pediatrician wanted to wait until he was 2, because boys are often slow to acquire language. She picked him up and left the exam room with him, calling over her shoulder, "I can't in good conscience let you walk out of here without a hearing test for big brother!" Wow! This doctor cares! Unfortunately, their audi was overbooked with patients. She let us go home, with STRICT orders to force our pediatrician into testing his hearing. It will be interesting to see if Matthew has some hearing loss - these things are often genetic and with the delayed speech... let's just say I have odds on finding a low frequency loss with this kid. Of course, my husband had apraxia as a kid, so it could be anything.

We are now scheduling all of our future appointments. We need a urinalysis, EKG, and I have just scheduled Matthew's hearing evaluation. We have another ABR scheduled for Nolan and another ENT appointment after that to schedule a CT scan and other testing. We are going to be busy with doctors for a while!

1 comment:

KathyD said...

Dear Leah,
I would greatly welcome an opportunity to discuss further the nice experience you had with the hearing test (ABR) for your son, Nolan. Apparently the equipment deployed was the VivoLink system, which is the patented hearing device from my company, Vivosonic Inc. We are the designer, manufacturer and distributor of this unique state-of-the-art testing device which requires NO SEDATION AND NO GENERAL ANAESTHETIC--a boon to parents! I would appreciate you getting in touch with me, as I am gathering anecdotal experiences from numerous parents and patients and clinicians. Thank you, Leah.
Sincerely,
Kathy Dimson
Community & Government Relations
Vivosonic Inc.
dimson@vivosonic.com
416-231-9997 ext. 296