Had my first annual visit with my dermatologist since getting hearing aids. I asked him about the risks of psoriasis in the ear canal and any possible involvement of the tympanic membrane. My doctor has been practicing for decades at a local university-affiliated institute and seems up-to-date on current knowledge, e.g., for topical application elsewhere on my limbs, he recommended a combined ointment of beta-methasone and calcipotriene soon after it came out and that combined ointment seems to work much better than using either separately on alternate days, etc. Better suppresses serious tissue reddening caused when using calcipotriene by itself, for example.
He said psoriasis in the ear canals is not a problem for most psoriatics although it is a possibility. Just to be gentle on inserting and removing domes or molds, etc. The doctor said that there is essentially no possibility of involving the tympanic membrane in any psoriatic ear reaction - he said it’s a different type of tissue (did he mean not “epidermal?”).
I have noticed that where my receiver wires rub against the top of my ear lobes that the tissue there has been gradually getting a bit psoriatic. So far it has not been much of a cosmetic or a comfort problem. A daily face-washing seems to take care of it. I do have desonide ointment, just about the weakest steroid there is, and permission to use it as needed even on very thin-skinned facial areas and I find an occasional application, if needed, to a specific area usually has a very good suppressive effect on any affected facial area - little reapplication is needed.
I am submitting this as a follow-up to the tone of the original OP’s post that seemed to indicate that psoriatics faced a serious risk of losing hearing due to aggravation caused by wearing hearing aids. Because psoriatic tissue can be an inflamed, raw area, I should imagine that affected areas can be at more risk of outside infection but I didn’t ask my dermatologist about that possibility for the ear canals (next year!).