Neurointerventional Diagnostic Testing

A Spinal angiogram is considered the gold standard when it comes to studying the blood flow and blood vessels that supply the spinal cord. This procedure is similar to a cerebral angiogram in that it provides high definition 3-dimensional images that aid in the diagnosis and treatment of diseases that affect the spinal cord such as arteriovenous malformations, fistulae, tumors, and spinal aneurysms.

Prior to a spinal angiogram, local and intravenous anesthesia is used for sedation. If you are unable to lie flat for a long period of time this procedure can be done under general anesthesia to ensure comfort. Like a cerebral angiogram, a small plastic tube called a catheter is placed in an artery near the groin, With image guidance the catheter is navigated to the main arteries that supply the spine. With the catheter in place contrast dye will flow through the catheter while multiple images are taken to examine the blood vessels in the spine. Often a smaller catheter, measuring just a few millimeters in diameter, can be introduced through the larger catheter for more detailed images if needed. The entire procedure lasts about 1 hour, after which being observed for a short period of time patients go home.

A test that is performed to accurately identify the areas in the brain that control movement, language, and memory is commonly referred to as a WADA test. Mapping these areas in the brain prior to surgery helps your neurosurgeon plan the safest approach for removing the epileptic focus or foci.

A cerebral angiogram is done prior to performing the WADA test. This is to evaluate the blood flow and blood vessels within the brain to make sure the WADA test can be performed accurately. Once the catheter is in place and the targeted areas in the brain have been identified, the WADA test begins. A baseline assessment neurological exam is performed by three different specialists: a neuropsychologist, neurologist, and epileptologist. Under image guidance an anesthetic agent, sodium amobarbital, flows through the catheter. The same neurological exam is again performed by the same group of doctors to accurately identify areas in the brain responsible for motor, speech, memory, and mental skills. The entire procedure lasts about one hour, after which the patient is observed for a short period of time before going home.

Petrosal sinus sampling is a new approach for patients with a Cushing's disease to accurately locate the pituitary tumor on the pituitary gland. In 20 to 30% of the cases, is difficult to determine the location of the tumor on the pituitary gland, even during the actual surgery. Inferior Petrosal Sinus Sampling is ordered by your endocrinologist or neurosurgery prior to surgery to help identify the abnormal side. The information collected during the test is used to provide better surgical planning for patients undergoing transsphenoidal pituitary surgery. In many centers, it is performed in all patients who do not have a definite macroadenoma seen on MRI.

Prior to undergoing petrosal sinus sampling it is necessary to perform a cerebral venogram. A cerebral venogram provides a roadmap of major veins in the brain. This is done by placing a small catheter in the large vein in the groin. With image guidance the catheter is navigated to the main veins that supply the brain. With the catheter in place contrast dye will flow through the catheter while multiple pictures are taken to examine the blood vessels in the brain to correctly locate the precise area of the brain where samples are to be drawn. The catheter is then advanced to the petrosal sinus and sampling begins. A Corticotrophin-releasing hormone is given through the catheters to enhance the sensitivity of the procedure. Samples are then sent to the laboratory for analysis. At the end of sampling all catheters are removed and direct pressure is held over the groin. The entire procedure lasts about two hours and after being observed for a short period of time patients go home.