Yes. The ADA does not require modifications that would fundamentally alter the nature of the services provided by the public accommodation. For example, it would not be discriminatory for a physician specialist who treats only burn patients to refer a deaf individual to another physician for treatment of a broken limb or respiratory ailment. To require a physician to accept patients outside of his or her specialty would fundamentally alter the nature of the medical practice.
If you have further questions, please contact your regional center.