Dictionary

Fflow sensitive MRI [FS MRI] A scan that combines functionalMRI with images of cerebrospinal fluid flow through theventricles and, if needed, the spinal cord.FISH test Acronym for Fluorescence In Situ Hybridization, thislaboratory technique is used to look at genes or chromosomesin cells and tissues. Pieces of DNA that contain a fluorescentdye are made in the laboratory and added to cells or tissues ona glass slide. When these pieces of DNA bind to specific genesor areas of chromosomes on the slide, they light up whenviewed under a microscope with a special light.focal [foe´ kal] Limited to a specific area.focal brain stem glioma [foe´ kal] A localized tumor of thebrain stem. These tumors represent about ten to twentypercent of all brain stem tumors. They can be solid or cystic,and can occur in any part of the brain stem.focal radiation [foe´ kal] High dose radiation delivered toan area just encompassing the tumor. Interstitial radiation andstereotactic radiosurgery (SRS) are two types of focal radiation.focal seizure [foe´ kal] Also called partial seizures, these affectonly one part of a cerebral hemisphere and symptoms dependon the specific part involved. There are two types: simplepartial and complex partial.focal symptom [foe´ kal] A symptom that helps identity thelocation of a tumor. The effect on a specific area of the brain.foci [foe´ sigh] The origin or center of a disseminated disease.foramen [foe ray´ men] An opening through a bone ormembrane. The foramen magnum (literally, the large opening)is the hole in the occipital bone through which the spinal cordenters the skull and continues as the medulla oblongata.foramen of Monro [foe ray´ men] The opening through whichcerebrospinal fluid flows from the lateral ventricles to the thirdventricle. Also called interventricular foramen.46formulary A limited list of medications approved by a hospital,an insurance company, etc. for use.fourth ventricle A fluid-filled cavity located in the posterior fossa,it is an extension of the central canal of the medulla oblongataand connects to the third ventricle via the cerebral aqueduct.fractionated Dividing the total dose of radiation to be given intoseveral smaller, equal portions delivered over a period of daysor weeks. Each portion is called a fraction.frontal lobe One of the four sections of the cerebralhemisphere.frontal sinus A hollow in the lower part of the frontal bone thatcommunicates with the nasal cavity.FS MRI Flow Sensitive MRI. A scan that combines functionalMRI with images of cerebrospinal fluid flow through theventricles and, if needed, the spinal cord.FSRS Fractionated Stereotactic Radio Surgery. A radiationtherapy technique that uses a large number of narrow, preciselyaimed, highly focused beams of ionizing radiation, delivered individed doses over a period of time (fractionated). The beamsare aimed from many directions circling the head to meet atthe tumor.FTE Full Time Equivalent (employee).functional Refers to function (performance) as opposed to form(structure).functional MRI This technique produces MRI images in a fastersequence than traditional MRIs. The increased speed permitsthe tumor’s use of oxygen to be depicted. This technique isimportant because it depicts an area of the brain “lighting up”when the patient performs a task such as moving a finger, orspeaking. In this way, brain maps of functional areas aregenerated, useful for preoperative surgical planning andintraoperative avoidance of functional or “eloquent” areas ofthe brain.) Also called echoplanar, “real time,” or Fast MRI.F47