- Electroencephalography (EEG) Standard and Complex Studies
- Long-Term Video Epilepsy Monitoring
- Transcranial Doppler Studies
- Embolic Detection
- Embolic Detection with the Addition of Micro bubbles
- Brainstem Auditory Evoked Potential
- Visual Evoked Potential
- Somatosensory Evoked Potential (Upper and Lower Extremities)
- Digital EEG Analysis
- Digital EEG & Epilepsy Detection
- Ambulatory EEG (24-72 Hour Studies)
- Neurological Intra-Operative Monitoring
WHAT IS A TRANSCRANIAL DOPPLER STUDY (TCD)?
A Transcranial Doppler Study is an ultrasonic test of the blood circulation in the head through a probe which emits sound waves to a specified depth and the returning sound waves are measured for direction of blood flow and pressure inside the artery. It is used in determining blood flow in such cases as stroke, vascular spasms, , intracranial vascular diseases, brain hemorrhage, vertebro basilar insufficiency, cerebral blood clots, and many other neurological disorders. A physician will review the TCD to aid your doctor in making a diagnosis and the proper course of treatment.
HOW ARE TRANSCRANIAL DOPPLER STUDIES PERFORMED?
A small hand held transducer (about 15 millimeters wide) is placed over a window. A window is a place where the bone is the thinnest. There are four major windows used for the test. First, the temporal window bone has a potential of 5 different locations in which the technologist will search for the best one. From the temporal window, 6 different arteries or arterial branches are located and measured. Second, the optical window allows two arteries behind the eye to be measured. Third, the carotid window will evaluate the internal carotid artery in the neck; and finally, four, on the back of the neck will allow for the posterior circulation coming up the shoulders to the neck and into the back of your head will be measured.
HOW MANY DIFFERENT TYPES OF TCD TESTING ARE DONE?
There are four different TCD testing procedures that are normally done here at Community Medical Center. They are the Complete Transcranial Doppler Study, Limited Transcranial Doppler Study, Embolic Detection, and the Micro Bubble Study.
Transcranial Doppler- For the Complete Study, all the vessels in the head are evaluated.
For the Limited Study, your doctor has to specify exactly what areas he/she would like to test. The testing has been described above.
Embolic Detection - Head gear is applied and a probe is placed on both sides and you lay quietly 20-30 minutes to see if your body has very small microblood clots circulating in your body.
Micro bubble Study - This is commonly referred to as a “Bubble Study”. This is performed in conjunction with embolic detection and requires an intravenous line to be inserted. During the study, a registered nurse from the Neuroscience Unit will inject agitated saline into your arm 4-5 times to see if any of the micro bubbles flow into your head. This is a safe test and no bad effects will occur. Agitated saline is caused when 1cc of air and 9cc’s of salt water are pushed back and forth between two syringes.
YOUR COOPERATION IS ESSENTIAL:
The more you can relax, the faster the test can be done.
AFTER THE TCD
The technologist will advise you when the test is completed. Normal daily activity can resume immediately. Your physician will be sent a copy of your results. Approximately two weeks following the completion of the test, you should contact your physician to discuss the results. The Neurophysiology Department cannot discuss the results of your tests with you.
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