Marian has ultra high frequency hearing loss. We sat in the little room together for the hearing test. Not to brag but I could hear all the sounds, but Marian couldn't. She sat in my lap as they played sounds from speakers on either side of her. A little on the left, a little on the right, and a toy would light up if she looked the correct direction. When the higher sounds played she didn't respond, they went a little louder, and no response still, they went a little louder and she turned her head with a huge smile. Not knowing what she now can't hear.
Her hearing loss is very mild. She can still hear these sounds but not at a low volume, so softly spoken or whispered S, F, and H will be difficult or impossible for her to hear. Hearing loss is also a part of NPC progression, so without treatment she would have lost this anyway, and even more. We should probably expect her to lose more hearing, but we are hoping she'll retain most of her hearing for at least the next several months as her speech develops.
She'll be re-tested next month and can do hearing aides when needed. We will see what unfolds. All in all a small price to pay for the chance to live, but still another slap in the face of this horrible disease. Its continuous efforts to take her away and ours for it to not.