Sharp pain before hearing loss

My friend is 67 and a couple years ago he had a sharp pain in his right ear. Later he had a few more sharp pains and then he lost his hearing in that ear. I believe by now it's almost a 100% hearing loss. A hearing aid only garbled his hearing so he couldn't hear even in his left ear. He saw a specialist, had a MRI and they just couldn't find anything at all. No idea why he's lost his hearing in one ear. I think it's odd the doctor's can't figure it out. I think he should have another opinion or two. Anyway, in the last week or so he's had sharp pains in his left hear so we are wondering if he's going to lose the hearing there and be totally deaf? Pretty scary stuff. Any ideas friends?