Making the Diagnosis
Tourette syndrome (TS) is diagnosed based on symptoms - a person must have both multiple motor tics and one or more vocal tics for at least one year to be diagnosed with TS. The motor and vocal tics, however, do not have to occur continuously or at the same time.
Doctors may order magnetic resonance imaging scans (MRIs), computerized axial tomography (CAT) scans, or blood tests, but their purpose is to rule out other neurological problems - not to find TS.
Most physicians can easily diagnose people with typical TS symptoms. However, people with atypical symptoms or symptoms that start later in life may be more difficult to diagnose. It may take a while before a person gets a diagnosis of TS, mainly because many mild tics may be attributed to other causes (e.g., constant sniffing due to allergies).