Radiation Therapy Flashcards
three princpal modalities used in the treatment of cancer
radiation theraphy
surgery
chemotherapy
most often delivered daily
monday - friday
2-8 weeks
dosages range from
2000 cGy and 8000 cGy
prescribes the quantity of radiation and determines anatomic region to be treated
radiation oncologist
responsible for calibration and maintenance of radiation-producing equipment and gives advice on dosage calculations
medical physicist
devises a plan for delivering treatments to irradiate tumor while protecting normal tissue
medical dosimetrist
obtaining radiogphs or CT scans
administering treatments
keeping accurate recods of dose delivered
monitoring the patents physical and emotional well being
radiation therapist
responsible for patient education on radiation side effects and side effect management
oncology nurse
biological effects of ionizing radiation observed
epilation
erythema
dr. emile grubb irradiated a women with carcinoma of the left breast
Jan 29 1896
dr. clarence skinner performed the first reported curative treatment using ionizing radiation on a woman with malignant fibrosarcoma
Jan 1902
the woman dr. skinner treated was declared free of her malignant fibrosarcoma
Apr 1909
two major categories for application of radiation for cancer treatment
external-beam
brachytherapy
also called teletherapy
the patient lies underneath a machine that emits radiation of generates a beam of xrays
external-beam
radioactive material is placed within the patient
brachytherapy
radioactive source is placed in close proximity to a lesion
mould technique
placement of radioactive source in the body cavity
intracavitary implant technique
radioactive source is placed directly into the tumor site and adjacent tissue
interstitial implant technique
for treatment of superficial lesions
low-energy beam deposits all or most of its energy on or near the surface
120-kVp superficial xray unit
for treatment of moderatly superficial lesions
250 kVp orthovoltage unit
average energy is 1.25 MeV
replaced orthovoltage units
first skin-sparing machine
known as the “work horse” reliablity and simplicity
cobalt-60 gamma ray source
is most suitable for tumors deep beneath the body
high energy
machine rotates around a fixed point and maintains the same distance from source of radiation
isocentric machine
source for high energy electrons
developed in 1952 first used in the us in 1956
6-35 MV linear accelerator or betartron