A new scan to help in difficult-to-diagnose cases of Parkinson’s disease or other parkinsonian syndromes is available at more than 80 U.S. hospitals, including some in the Chicago area, since receiving federal approval earlier this year.

During the DaTscan test, an imaging drug is injected into a patient’s bloodstream and the patient undergoes a single-photon emission computed tomography, or SPECT, scan. Patients with Parkinson’s disease or other parkinsonian syndromes have scans that show low levels of dopamine, the neurotransmitter critical in controlling movement and other muscle functions.

In cases where a diagnosis isn’t necessarily clear-cut, the DaTscan offers important advances in patient care and treatment, said Dr. Michael Rezak, director of the Movement Disorders Center at Central DuPage Hospital, where the scan is offered.

Read more at the Chicago Tribune.