Mosby exam Flashcards
For portal verification, bone tissue contrast is better using a kilovoltage imager rather than a megavoltage imager due to the absence of:
screens in the MV beam
the most common type of leukemia in children is
ALL
the amount of kinetic energy transferred in a medium per unit mass is referred to as
KERMA
the quality factor for gamma radiation is
1
the unit of exposure in the air is the
Roentgen
which of the forces of nature is the weakest?
gravitational force
the prodromal stage of acute radiation syndrome consists of
nausea
what does the fletcher suite applicator consist of
tandem and a pair of ovoids
why is IR 192 the commonly used source in HDR after loading brachytherapy
it has a high specific activity and lower photon energy
the class of cytotoxic agents that has the potential to burn the skin of the administered is:
alkalizing agents
in one month, the output of a cobalt machine would reduce by about:
1%
what thickness of cerrobend would be equivalent to 5 cm of lead
6
the tail of the pancreas is located
in the hilum of the spleen
which of the following techniques is used to treat early pre=cancers of the cervix?
loops electrosurgical excision
linear energy transfer is measured in units of
keV/micrometer
a joule is a unit of
energy
during xray production, the process by which electrons are liberated at the cathode is known as
thermionic emission
the parathyroids are located on the
posterior surface of both thyroid lobes
for patients with bladder cancer, the preoperative radiation treatment fields should be large enough to include the bladder and regional nodes such as
obturator, external iliac, and internal iliac
the use of iodine or barium contrast in CT scanning exploits the characteristics of:
photoelectric effect
the production of x-rays by bremsstrahlung ____ with ____ atomic number (increases/decreases)
increases with increasing atomic number
the attenuation of cerrobend is less dense than lead by about
15%
an allogenic bone marrow transplant is one in which bone marrow is
received from a sibling or person immunologically compatible
the transient sensation of electrical shock traveling down the neck and extremities following radiation to the spine is called
Lhermitte’s sign
diastolic pressure is within the arteries that exists while the heart is:
resting
suitable material for skin sparing, customized to use as a tissue compensator include all of the following except:
superflab
the most important method used to confirm malignancy is
histolopathological screening
if a healthcare worker is accidentally punctured by a contaminated needle, the potential route of disease transmission is
FOMITE
which tumor marker among the following is helpful in the diagnosis of testicular cancer
AFP alphafetoprotein
with all other factors remaining the same, increasing the field size from 6x6 to 10x10, backscatter would
increasing the field size increases the backscatter
the energy of an electromagnetic radiation is inversely proportional to it’s
wavelength
the primary lymphatic drainage for the lower lip would be to the
submental nodes
Metastatic disease may lead to an abnormal accumulation of fluid in the pericardial sac. This may lead to:
pericardial tamponade
A grade 1 morbidity score for the colon would indicate:
change in frequency of bowel habits
if custom blocks need to be used, the shadow tray will __ the output.
decrease
The natural slope of the chest may cause high dose regions in the upper mediastinum. This area of increased dose may be managed by the use of a:
custom compensator
adults undergoing total body irradiation may be treated at an extended distance while assuming the position of
semi recumbent with the knees bent on a gurney
if the upper mantle is treated, the arms may be elevated above the head or positioned akimbo in order to move
the axillary nodes away from the field
the seven warning signs of cancer include:
dot——
if a patient has a large pelvic tumor involving the bladder and prostate and there is a presacral mass, the best arrangement would be
opposing anterior and posterior fields
what reduces the risk of ovarian cancer?
birth control pills, pregnancy, breastfeeding, tubal ligation, and hysterectomy
a normal pulse rate in the adult is
60-90 bts/min
when an actual doe delivered needs to be verified, in vivo dosimetry can be accomplished by using
TLDs
if there is a serious complication during therapy, the patient could initiate legal action against:
the physician, the hospital, the therapist
when treating areas in the head and neck, the most reproducible position is
supine
normal rectal temperature for the adult in Fahrenheit is
99.6
the systolic pressure represents
the highest point reached during contraction of the ventricles
the volume larger than the treatment volume receiving some significant dose is the
irradiated volume
while treating early to midstaged vulvar cancer, the patient may be positioned in the frog legged position in order to avoid
increased dose in the inguinal fold
whole brain treatments are best delivered using
6 mV photons
which of the following are adverse results of cachexia
impairment of immunities, changed in metabolism, electrolyte imbalance
the signs of petite seizure include
sudden cessation of focus and response, sudden gasp or sharp vocal cry
lucite is often used as the material for positioning devices. one major concern when this material is in the path of the treatment beam
beam attenuation
if a patient is experiencing a severe reaction in the perineal area they should not
use hot baths to soothe the skin
which of the following best defines a wedge factor
ratio of dose at depth with the wedge inserted to the dose at depth with no wedge inserted
unsealed radioactive sources must be safely handled by
wearing gloves and protective clothing while working, preparing solutions in a well ventilated work area, covering work areas with plastic, glass, or stainless steel
which type of chemotherapy is known to cause hearing loss
cisplatin
an example of a non stochastic effect from radiation exposure
erythema
malignant neoplasms that originate in lympho-reticular tissues are called
lymphomas
a common symptom of prostate carcinoma is
dysuria
the actual physical dimensions of the tumor, including regions of presumed occult spread is the
tumor volume
to achieve a neutral head position for a large patient with a large, barrel chest, the therapist may use a
high headrest
among the following, which of the following sites is common for the development of Ewings sarcoma
pelvis
skin cells are called
epithelial
total dose to the lumpectomy site following accelerated partial breast irradiation utilizing high dose rate brachytherapy will be approximately
45 Gy
misalignment of treatment fields may result from all of the following except
dose rate change
the trendelenberg position is appropriate for a patient experiencing a medical emergency such as
shock
patients should be weighed and remeasured through the treatment axis periodically so that
anatomic variations can be monitored
when treating a patient with prostate cancer, which of the following factors would not cause prostate movement
cecum volume
the average energy deposited per unit path length to a medium by ionizing radiation as it passes through that medium best describes
a linear energy transfer
which theory of radiation interaction is illustrated by the operating principles of an ionization chamber
Bragg gray cavity theory
photon production from a diagnostic X-ray tube requires
direct current, voltage potential
anaplasia describes
loss of differentiation
when treating superficial lesions, a thin lead sheet with an opening for the treatment field may be placed on the patients skin for
field shaping
in the maintenance phase of managing ALL, whole brain irradiation may be given with the inferior border of the treatment field at the
C2
mechanical errors may be reduced by
performing regular quality, allowing periodic overhaul by equipment engineers, daily observation of equipment
the ability to displace the small bowel away from pelvic fields depends on
whether the patient has had previous pelvic surgery
a patient who is documented as afebrile has
normal body temperature
reductions in ___ intake have coincided with ___ rates in colon cancer
fiber, increasing
