Pulmonary fibrosis, asthma, other breathing issues

Hello all.  I'm new to posting on the forums.  I lived in Aomori prefecture when I was younger and didn't have any issues. Two years ago I got a very bad illness and have lung scarring.  As a result, I'm on portable O2 and asthma therapies.  I'm trying not to let this keep me from pursuing my dream of returning to Japan to teach English.  I know Yokohama and Tokyo are pretty bad for asthma sufferers.  I've been looking into Osaka and Kobe.  Does anyone have any information regarding the air quality there or any recommendations on hospitals/clinics with pulmonary specialists?  I've only been able to find ONE on the internet.  Any help is greatly appreciated.  :)

I don't have asthma but my Japanese husband does and a friends son who was here for a year had allergies that were 'showing up more towards the end of July. Also my son gets shortness of breath, when excited, only around this time. There is the Yellow sand from China that comes across central Japan. It is very fine when it hits us,  and in spring the car gets a good covering of it. I'm in Gifu near Sekigahara. We seem to have lovely air around here except perhaps for this sand. You might need to watch for that,  I guess, but that hasn't effected anyone I know. Just before/ around Cherry blossom time is tough for allergie sufferers, which may make things worse, depending. Usually people wear a mask when going out / on the street at this time to be sure. So that's good for you as you would seem quite normal if you did this too.
Could be that you need to carefully arrange your holiday time?!
Ah, I don't know about pulmonary, but Nagoya has some great hospitals.