Our team uses a variety of diagnostic tests to obtain information about a brain tumor. We perform neurological exams to check mental status and memory, cranial nerve function (sight, hearing, smell, tongue and facial movement), muscle strength, coordination, reflexes and response to pain. Additional tests include:
A hearing test performed by an audiologist that detects hearing loss caused by tumors near the cochlear nerve, such as an acoustic neuroma.
A biopsy is a procedure in which a pathologist examines a small amount of tumor under a microscope. A biopsy is performed when a diagnosis cannot be made clearly from other tests or scans. A needle biopsy can be taken as part of an open surgical procedure to remove the tumor or as a separate diagnostic procedure. A stereotactic biopsy is like a needle biopsy but is performed with the use of a stereotactic head frame and a computer to precisely locate the tumor and direct the needle. This more complex procedure is used for deep tumors in critical locations.
Computed Tomography (CT) scan
A Computed Tomography Scan (CT Scan) is a noninvasive test that uses an x-ray beam and a computer to make 2-dimensional images of the brain and bony structures surrounding it.
During the test, the patient lies on a table and the CT Scanner rotates around the patient and takes pictures. These two-dimensional images of the brain can be looked at individually or combined to create a three-dimensional image.
A dye (contrast agent) may be injected into the patient’s bloodstream to allow a more precise view of the targeted body tissues. This dye contains iodine, which moves through the blood stream and is absorbed in the tissues. The x-rays cannot penetrate the iodine and the targeted tissues are enhanced on the scan.
Diffusion Tensor Tractography
An imaging technique that generates images of critical white-matter tracts in the brain that must be avoided and protected during surgery. White-matter tracts are electrical connectors between different parts of the brain.
A blood or urine test used to detect abnormal hormone levels caused by pituitary tumors.
Functional MRI (fMRI)
A series of MRI images taken seconds apart that capture blood oxygen levels in parts of the brain that are responsible for movement, perception and cognition. By revealing the location of these critical areas, fMRI allows physicians to avoid and protect them during surgery.
The intraoperative MRI suite at the UC Medical Center enables neurosurgeons to examine a tumor site and to confirm, while the patient is still under anesthesia, that the tumor has been entirely removed. If the MRI images show remaining fragments of the tumor, neurosurgeons can complete the tumor removal at that time. Confirmation that a tumor has been completely removed has the potential to spare the patient additional surgery and/or radiation treatment following surgery.
Brain tumor specialists began using the Hitachi AIRIS II MRI at at the UC Medical Center in 1997 and have a decade of experience with this important technology. The intraoperative MRI is used routinely during the surgical removal of gliomas (both low-grade and malignant) and pituitary tumors.
Lumbar Puncture (spinal tap)
A minimally invasive procedure used to examine cerebrospinal fluid for tumor cells, proteins, infection and blood.
Magnetic Resonance Imaging (MRI) scan
A Magnetic Resonance Imaging (MRI) scan is a noninvasive test to evaluate brain lesions and their effects on surrounding brain tissue. MRIs use a magnetic field and radiofrequency waves to give a detailed view of soft tissues of the brain in 3-dimensional slices that can be taken from the side or the top as a cross-section. An MRI image is very detailed, allowing physicians to see abnormalities that otherwise may be difficult to identify.
A dye (contrast agent) may be injected into the patient’s bloodstream to allow a more precise view of the targeted body tissues. This dye contains gadolinium, which moves through the blood stream and is absorbed in certain tissues. Since the gadolinium has magnetic properties, the targeted tissues are enhanced on the scan.
Positron Emission Tomography (PET) scan
A Positron Emission Tomography (PET) Scan is a nuclear imaging test that includes a computed tomography (CT) scan and the injection of a radioactive tracer through an IV. Images reflecting accumulation of the tracer are superimposed over the CT scan in two-dimensional cross-sections for detailed analysis. The PET scan shows how the brain is using energy, in real time. Unlike x-ray, CT, or MRI scans, which show the brain’s anatomy, a PET scan can provide information about how the brain is working.
PET scans help monitor the activity of cancerous tumors. Because malignant cells grow at such a fast rate, physicians often use PET scans to monitor how fast malignant cells grow as well as the impact of treatment therapies. PET scans are also used to evaluate medically uncontrolled seizures.
Visual Field Acuity test
A simple test performed by a neuro-ophthalmologist to detect vision loss.