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Transcranial Doppler

A transcranial doppler test (TCD) uses ultrasound waves to measure the blood flow rate in the main (cerebral) arteries of the brain. It helps detect blockages, narrowing or spasms of the arteries. The exam does not involve the use of needles or injections. TCD is done in the Vascular Lab and takes about an hour.

Before the Test
There are no diet or activity restrictions before this test.

Day of the Test

Arriving at the Hospital
Check in at the Vascular Lab reception desk (Galter Pavilion, 251 E. Huron St., 8th floor) 15 minutes before your test time. Parking is available.

Be sure to bring:

  • Written doctor's order for the test
  • Insurance card
  • Medicare card (Medicare patients only)

For their own safety, children under the age of 16 may not visit the testing area.
They may stay in the waiting room with a responsible adult.

During the Test
It is important to lie still and not talk during this exam.

  • The technologist (tech) will assist you onto an exam table. Then the tech will apply gel and moves a small hand-held device (transducer) over the skin on each side of your head, under your chin, over your closed eyelids and at the back of your neck.
  • The transducer transmits sound waves to a monitor that records the blood flow rates. You may hear a pulsating sound that corresponds to your heartbeat.

After the Test

  • The tech will provide towels to help remove the gel.
  • You are then free to leave.
  • You may resume your normal diet and activities.
  • Most often, initial findings are sent to your doctor within 48 hours. A full report follows in about five business days.

Contact
Vascular Lab
(312) 926-2746

Review Date: 01/05

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