Dr. Russell Cohen at the U of Chicago. Any of the doctors at the U of Chicago clinic are preeminent (sp?) and worth the trip.
You're probably going to be able to get an appt. with a suburban specialist sooner but I would call and make an appt. at the U of Chicago too - and keep it. These guys are among the best and it can only be to your advantage to see them once every six months - that way when the **ht hits the fan you're able to get in right away and not be considered a new patient who has to either a) wait 3-4 months to get in or b) take the drastic action of showing up at U of C's ER and hope to get admitted through the ER.