DEFINITIONS I



ICP
Intracranial pressure, harmful when increased.

IICP
Increased intracranial pressure.

immunotherapy
Use of the body's immune system to fight tumors. See biological response modifier.

inaccessible
See accessible.

infiltrating
Refers to a tumor that penetrates the normal, surrounding tissue.

informed consent
The right to have information explained to you so that you fully understand and agree to the nature of the proposed treatment.

interstitial radiation therapy
The implantation of radioactive seeds directly into a tumor.

intra-arterial
Injection into an artery (that may supply a tumor).

intracerebral
Located within the cerebral hemispheres (cerebrum). See extracerebral.

intracranial
Within the skull.

intradural
Beneath the dura mater.

intramuscular
Into a muscle.

intrathecal
Injection into the sub-arachnoid space of the meninges. Usually done by lumbar puncture.

intratumoral
Injection into a tumor (usually performed during surgery).

intravenous
Injection into a vein.

intraventricular
Injection into a ventricle.

invasive
Refers to a tumor that invades healthy tissues. The opposite of encapsulated. Also called diffuse or infiltrating.

ipsilateral
Affecting the same side. See contralateral.

irradiation
Treatment by ionizing radiation, such as x-rays, or radioactive sources such as radioactive iodine seeds. See radiation therapy.