House Bill 1646, also known as Senate Bill 1795, amends the Tennessee Code to require health insurers and health maintenance organizations to provide coverage for medically necessary treatments related to acquired brain injuries (ABIs). The bill defines various terms related to ABI treatments, including cognitive rehabilitation therapy, neurofeedback therapy, and community reintegration services, among others. It mandates that coverage must not impose lifetime limitations or unreasonable annual limits on treatment sessions and ensures that any limitations on rehabilitation services are clearly stated and separate from post-acute rehabilitation limitations.

Additionally, the bill stipulates that only clinical peer reviewers can conduct preauthorization or utilization reviews for the required services. To qualify for reimbursement, practitioners or treatment facilities must possess the necessary licenses, certifications, or accreditations. The commissioner of commerce and insurance is tasked with creating a process for expedited appeals of adverse determinations made by insurers regarding these services. The act is set to take effect on January 1, 2027, and will apply to insurance contracts entered into, amended, or renewed after that date.