Dr. Hain, aka the Dizzy Doctor, is an MD whose practice is Chicago Dizziness and Hearing, which is affiliated with Northwestern, and shares space with Chicago Ear Institute and Dr. Wiet at the Chi office on N. Michigan.
He's renowned for treatment of all kinds of dizziness and has written a lot of explanatory material about acoustic neuromas also.
He is actually the first doctor I made an appointment with on my journey, since dizziness was my presenting symptom. He's very nice and though he is an MD, my impression of him was that he has just as much of a research bent as anything.
From his Web site: Chicago Dizziness and Hearing is the clinical practice of Timothy C. Hain, M.D., and Marcello Cherchi, Ph.D., M.D. We are "otoneurologists", specializing in diagnosis and treatment of dizziness and hearing disorders. Our goal is to offer compassionate and expert health care.
Dr. Hain: Professor of Neurology, Otolaryngology, and Physical Therapy/Human Movement Science, Northwestern University Medical School, Chicago IL, USA. On staff at Northwestern Memorial Hospital. Education: MD and Neurology Residency: University of Illinois, Chicago IL. Fellowship: Johns Hopkins University (Neurophysiology and Neuro-ophthalmology). Board certified in Neurology (1981).
ETA: link to acoustic neuroma overview:
http://www.dizziness-and-balance.com/disorders/tumors/acoustic_neuroma.htm