Black and Yellow Flashcards
Regarding linear accelerators, which of the following is TRUE?
a. Maximum photon energy is equal to the E of the electron striking the target
b. The bending magnet is rotated out of the beam in the electron mode
c. The beam current is higher in the electron mode than in the photon mode
d. The scattering foil is the primary component for photon production.
a. Maximum photon energy is equal to the E of the electron striking the target
1 mSv is equal to ____ rem
0.1 rem
If the total body is exposed to a dose of 4500 cGy in a single exposure, the most likely cause of death would be:
a. infection and low blood counts
b. Severe damage to the intestines
c. Cerebral edema
d. Death would not be likely with dose
c. Cerebral edema
By what factor does the intensity decrease when someone moves 10 meters to 20 meters away from a radioactive source?
a. 2
b. 4
c. 10
d. 20
b. 4
What is the allowable cumulative exposure for a radiation worker?
a. one rem X the workers age in yrs
b. five rem X the workers age in decades
c. 100 rem X the workers age in yrs
a. one rem X the workers age in yrs
Which of the following are interacions between an incident photon and an atomic nucleus?
a. Photoelectric
b. Compton
c. Coherent
d. Pair Production
d. Pair Production
A barrier that attenuates the useful portion of the beam to be required degree is known as?
a. Secondary Barrier
b. Incident Shielding
c. Tenth Value Layer
d. Primary Barrier
d. Primary Barrier
A “star” shot on a linear accelerator is performed to test the rotational axis of the :
- collimator
- couch
- gantry
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
Direct exposure to lasers that are used for patient alignment purposes can be a hazard for the
a. Pituitary
b. Retina
c. Commissure
d. Inner Ear
b. Retina
The average photon beam energy produced by a 6 MV linear accelerator is approx _____ MV:
a. 2
b. 4
c. 6
d. 9
a. 2
Which of the following tisues arise from mesenchymal stem cells (MSC)?
- Blood
- Cartilage
- Bone
a. 1 only
b. 2 only
c. 2 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
In bremsstrahlung radiation, the incoming electron:
a. ineracts with an orbiting electron
b. is deflected by the nucleus of the atom
c. creates a positive and negative ion
d. cascades to a lower energy state
b. is deflected by the nucleus of the atom
Exposure is:
a. Measure of ionization in air
b. Known is a biological dose equivalent
c. The absorbed dose multiplied by the quality factor
d. The possibility of a random interacion
a. Measure of ionization in air
Which of the following does not ionize directly?
a. Proton
b. Neutron
c. Alpha particle
d. Electron
b. Neutron
The half life of cobalt-60 is:
5.3 yrs
Linear accelerators have which of the following type of target?
a. Hooded anode
b. Waveguide
c. Transmission
d. Rotating cathode
c. Transmission
Klystrons and Mangetrons are:
a. Radiaion monitors
b. Microwave sources
c. Monitors used for mechanical motions
d. Beam shaping devices
b. Microwave sources
Which of the following is the most common metastatic site for prostate cancer?
a. Lung
b. Liver
c. Bone
d. Brain
c. Bone
The last part of the colon that leads into the rectum is known as the:
a. Ascending colon
b. Hepatic colon
c. Descending colon
d. Sigmoid colon
d. Sigmoid colon
Why do high E photon accelerators require flattening filters?
a. To increase the penetrating ability of the beam
b. To reduce dose rates to a safe level
c. To filter out low E photons
d. To decrease the intensity along the central axis
d. To decrease the intensity along the central axis
Lead alone could be used in room shielding when the following interactions predominate:
a. Photoelectric
b. Bragg Peak
c. Pair production
d. Compton scattering
a. Photoelectric
The intensity of a radiation beam is measured at a distance of 100 cm and is found to be 150 cGy/min. What is the intensity of this beam at 105 cm?
a. 136 cGy/min
b. 143 cGy/min
c. 157 cGy/min
d. 165 cGy/min
a. 136 cGy/min
Inv sq law
(old distace / new distance) ² x dose
(105 cm/100cm)² x 150 cGy/min
136.05 cGy/min
What does ALARA mean?
As Low As Reasonable Achievable
The most common thermoluminescence material used in radiation dosimetry is:
a. CaSO4
b. LiF
c. CaF2
d. Li2B
b. LiF
Lithium Flouride
The angle of the mandible is generally located at which cervical vertebra level:
a. C1
b. C3
c. C5
d. C7
b. C3
The trachea is a hollow tube about 10 cm in length that exends from the larynx to a bifucation called the:
a. bronchus
b. sephanous
c. tributary
d. carina
d. carina
Monitoring of dose rate and field symmetry is best accomplished by using a (an):
a. Pocket dosimeter
b. Ion chamber
c. TLD
d. GM counter
b. Ion chamber
In the Pancreas, where do most tumors originate?
a. head
b. tail
c. body
c. hilum
a. head
Effects for which the severity of the effect in the individual varies with the radiation dose, and threshold usually exists is called:
a. Stochastic
b. Deterministic
c. Acute
d. Protracted
b. Deterministic
Which of the following devices are used for area surveys:
- Ionization chambers
- Parallel-plate chambers
- Geiger-Mueller detectors
a. 1 and 2 only
b. 1 and 3 only
c. 2 and 3 only
d. 1, 2, and 3
b. 1 and 3 only
According to NRC regulations, what is the MPD for those who are NOT trained radiation workers?
a. 0.1 rem/yr
b. 1.0 rem/yr
c. 1.25 rem/yr
d. 5.0 rem/yr
a. 0.1 rem/yr
The categories of visitors who are excluded from visiting a radioactive iodine patient are:
a. Females who have reproductive potentially and children of any age
b. Elderly females and children under 13 yrs of age
c. no categories are excluded bc radiation safety precautions are in effect
d. Pregnant women and children under 18 years of age
d. Pregnant women and children under 18 years of age
The section of the bladder between the ureters and the urethra’s is known a the:
a. trigone
b. urogenital diaphragm
c. calyces
d. muscularis propria
a. trigone
Which is the largest parasanal sinus cavity?
a. nasopharynx
b. sphenoid
c. maxillary
d. frontal
c. maxillary
Bolus can be used to:
- Flatten out surface irregularities
- reduce beam penetration
- increase surface dose
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
According to AAPM TG-40, gantry/collimator angle indicators on the linear accelerator must agree within _____ degrees.
a. 1
b. 2
c. 3
d. 5
a. 1
Lung cancer frequently spreads to:
- Brain
- Pancreas
- Bone
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
c. 1 and 3 only
What is the purpose of the scattering foil in a linear accelerator?
a. increase the intensity of the beam
b. Provide uniform electron fluence
c. Absorb radiation
d. Flatten out photon beam
b. Provide uniform electron fluence
What is the approx Dmax at 10 mV linear accelerator?
a. 1 cm
b. 1.5 cm
c. 2 cm
d. 2.5 cm
d. 2.5 cm
Photoelectric interactions of a 60 keV beam are greatest in
a. water
b. fat
c. muscle
d. bone
d. bone
Which of the following structures is most radiosensitive (susceptible to long term damage at the lowest dose)?
a. Spinal cord
b. Heart
c. Lung
d. Liver
c. Lung
The stomach is located in the:
a. Right upper quadrant
b. Right lower quadrant
c. Left upper quadrant
d. Left lower quadant
c. Left upper quadrant
What symptoms are most often associated with carcinomas of the cervix?
- Vaginal discharge
- Vaginal bleeding
- Bloating and weight gain
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
a. 1 and 2 only
What does the Oropharynx region include?
- BOT
- Tonsil
- Soft palate
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
From what type of tissue do most sarcomas arise?
a. Epithelial
b. Connective
c. Nerve
d. Skin
b. Connective
Referring to the MRI scan, the outlined organ is/are the:
a. Seminal veasicles
b. Stomach
c. Pancreas
d. Spleen
c. Pancreas
Where is a sarcoma most likely to metastasize?
a. Bone
b. Lung
c. Blood
d. Brain
b. Lung
When a pt presents with a bloody nasal discharge and a neck mass, the mostlikely diagnosis is:
a. Larynx cancer
b. Hypopharyngeal cancer
c. Nasopharynx cancer
d. Bone mets
c. Nasopharynx cancer
Which of the following is the most common primary brain tumor in adults?
a. Glioma
b. Meningioma
c. Medulloblastoma
d. Mets
a. Glioma
With breast cancer which of the following patterns of lymph node drainage occurs most often?
a. Internal mammary
b. Axillary
c. Supraclavicular
d. Mediastinal
b. Axillary
The most common site for metastatic spread of carcinoma of the penis is the:
a. Inguinal nodes
b. Periaortic nodes
c. Lungs
d. Liver
a. Inguinal nodes
Hypofractionation is:
- Treatement given in fewer fractions than standard
- Use of very low dose rates
- treatment given 2 or more times per day
a. 1 only
b. 2 only
c. 1 and 3 only
d. 1, 2, and 3
a. 1 only
The epiglottis is a flap of cartilage that folds back to cover the entrance of the:
a. Hypopharynx
b. Esophagus
c. Trachea
d. Larynx
d. Larynx
The most common histopathology of endometrial cancer is:
a. Adenocarcinoma
b. SCC
c. Clear cell
d. Mixed cellularity
a. Adenocarcinoma
The largest lymphoid tissue is the:
a. Liver
b. Spleen
c. Thymus
d. Jugulodiagastric node
b. Spleen
In the normal adult male the prostate is located ______ to the bladder
a. superior
b. inferior
c. posterior
d. anterior
b. inferior
Breast cancer mets to:
- Bone
- Lung
- Brain
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
The lower constricted portion of the uterus is called the:
a. Endometrium
b. Myometria
c. Cervix
d. Peritonial
c. Cervix
The vocal cords are found within in a structure formed by cartilage called:
a. Pharynx
b. Trachea
c. Larynx
d. Vallecula
c. Larynx
What type of lung cancer may need prophylactic brain irradiation?
a. small cell
b. Large cell
c. SCC
d. Adenocarcinoma
a. small cell
What cancer is “peau de orange” associated with?
a. Basal cell
b. Melanoma
c. Breast
d. Prostate
c. Breast
The inguinal lymph nodes are generally included in which of the following treatment sites?
a. Cervix
b. Vulva
c. Prostat
d. Rectum
b. Vulva
Nasopharyngeal tumors drain through what lymph node group first?
a. Posterior cervical
b. Submental
c. Submaxillary
d. Supraclavicular
a. Posterior cervical
The most common type of breast cancer is:
a. Tubular
b. Lobular
c. Infiltrating Ductal
d. Adenoidcystic
c. Infiltrating Ductal
Referring to the CT scan to the right, the arrow is pointing to the:
a. Kidney
b. Stomach
c. Gallbladder
d. Spleen
c. Gallbladder
If a pathology report indicates a stage of T1N0M3, what can be said about the lymph node involvement of th nodes sampled?
a. Positive nodes are found close to the primary tumor
b. The nodes were unable to be sampled
c. No positive nodes were present
d. Positive nodes are found at distant sites
c. No positive nodes were present
Which of the following is the most common site for a spinal cord compression?
a. Cervical spine
b. Thoracic spine
c. Lumbar spine
d. Sacrum
b. Thoracic spine
The tolerance dose (TD5/5) of the whole liver using standard fractionation (180-200 cGy/day) is:
a. 1500 -2000 cGy
b. 2500-3000 cGy
c. 3500-4000 cGy
d. 4500-5000 cGy
b. 2500-3000 cGy
The degree of cellular differentiation and rate of tumor growth is the:
a. Stage
b. Grade
c. Etiology
d. Epidemiology
b. Grade
When treating the entire CNS axis, the bottom of the spine port generally extends to the level of _____ when encompassing the cauda equina.
a. L3
b. L4
c. L5
d. S2
d. S2
A multiple field technique (3 or more fields) is generally utilized when treating pituitary tumors, opposed to two lateral fields, to avoid an excessive dose to which of the following structures?
a. Eyes
b. Optic chiasm
c. Temporal lobes
d. Sella turcica
c. Temporal lobes
The common iliac nodes are generally found around the level of:
a. C2
b. T10
c. L2
d. L5
d. L5
Where is the spleen located?
a. LUQ
b. LLQ
c. RUQ
d. RLQ
a. LUQ
What external landmark can be used to localize the top of the larynx?
a. Thyroid prominence
b. Hyoid bone
c. Cervical vertebrae
d. Waldyer’s ring
a. Thyroid prominence
The collapse of a part or all of the lung, which often results from bronchial obstruction is termed:
a. Bronchiectasis
b. Atelactasis
c. Pneuomoniis
d. Pleurisy
b. Atelactasis
When treating the maxillary antrum, which neighboring structure is most sensitive?
a. Eye
b. Pituitart
c. Spinal cord
d. Brain
a. Eye
Te pituitary is located:
a. 2cm post and 2cm inf to the EAM
b. 2cm ant and 2cm sup to the EAM
c. 1cm post and 2m sup to the EAM
d. 2cm ant and 2cm inf to the EAM
b. 2cm ant and 2cm sup to the EAM
The Trachea bifucates at the level of:
a. C4-C5
b. T12-L1
c. T4-T5
d. L4-L5
c. T4-T5
When treating a breast pt, the slope of the sternal notch to the xiphoid could be corrected by:
a. Aquaplast
b. Slant board
c. Arm board
d. Vaclok system
b. Slant board
When treating a pt with cancer of the tongue, what is the purpose of putting a bite block (tongue gag) in the pt’s mouth?
a. Flatten tongue
b. Potect teeth
c. Localize mandible
d. Alter dose distribution
a. Flatten tongue
What external landmark can be used to locate the carina?
a. Thyroid prominence
b. Axilla
c. Angle of Louis
d. Clavicle
c. Angle of Louis
The xiphoid is located at the level of ___-___.
T9-T10
The vallecula is located at the level of which of te following anatomical structures:
a. Pyriform sinus
b. Thyroid cartilage
c. Hyoid bone
d. Cricoid cartilage
c. Hyoid bone
The inferior border of a larynx port for a vocal cord carcinoma should anatomically correspond to:
a. Bottom of thyroid cartilage
b. Cricoid cartilage
c. Hyoid bone
d. First tracheal ring
b. Cricoid cartilage
If you are using a gonad shield when treating a pt with seminoma on a 6 MV linear accelerator, why cant all of the scatter to the testicle be eliminated?
a. Internal scatter from the pt cannot be eliminated
b. The shield would have to be too tick
c. Part of the testicle must be exposed to properly treat the pt
d. A 6 MV machine creates more scatter to the testicles when a testicular shield is used
a. Internal scatter from the pt cannot be eliminated
What is the TD 5/5 tolerance dose using standard fractionation, for the lens of the eye?
a. 450 cGy
b. 1000 cGy
c. 2000 cGy
d. 5000 cGy
b. 1000 cGy
If a pt has a reaction to contrast media, you would expect to see all of the following EXCEPT:
a. Hypotension
b. Choking
c. Incontinence
d. Pruritis
c. Incontinence
The pt’s chin is tilted down when treating a pituitary gland to avoid the:
a. eyes
b. Surrounding brain tissue
c. Spine
d. Base of skull
a. eyes
What is the technique in which a skin cancer is removed and examined layer at a time?
a. Curettage
b. Cryosurgery
c. Moh’s surgery
d. Dermobrasion
c. Moh’s surgery
What type of lung cancer has the highest incidence of mets at presentation?
a. Small cell
b. Large cell
c. SCC
d. Adenocarcinoma
a. Small cell
Which of the following areas are generally encompassed in a “German helmet” radiation port when treating acute lymphocytic leukemia?
- Cribiform plate
- Meninges
- Posterior retina
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
A Strontium-90 applicator may be useful in the treatment of which of the following diseases of the eye?
a. Reinoblastoma
b. Malignant melanoma
c. Pterygium
d. Metastasis
c. Pterygium
The tolerance dose (TD 5/5) for the whole brain using standard fractionation is approx:
a. 3500 cGy
b. 4500 cGy
c. 5500 cGy
d. 6500 cGy
b. 4500 cGy
Which of the following is the MOST radiosensitive structure?
a. Liver
b. Spine
c. Brain stem
d. Optic chiasm
a. Liver
A non-osseous tumor of the bone marrow is:
a. Fibrosarcoma
b. Chondrosarcoma
c. Osteosarcoma
d. Multiple Myeloma
d. Multiple Myeloma
The false vocal cords are located ______ to the glottis.
a. Anterior
b. Posterior
c. Superior
d. Lateral
c. Superior
What is the primary reason to angle the gantry posteriorly when treating Grave’s Disease with two lateral fields?
a. To avoid divergence into the lens
b. To assure coverage of the posterior orbit
c. To increase the dose to the orbital tissue
d. To assure coverage of the protruding eye
a. To avoid divergence into the lens
What fraction would you multiply an electron energy by to estimate the 90% isodose range?
a. 2/3
b. 1/2
c. 3/8
d. 1/4
d. 1/4
A pt is to receive 300 cGy per day on a Cobalt-60 unit through a single posterior field. The dose rate in air at 80cm is 105 cGy/min and the backscatter factor is 1.029. The PDD is 87.5%. Find the treatment time to deliver the prescribed dose.
a. 4 min 22 sec
b. 3 min 12 sec
c. 3 mi 10 sec
d. 2 min 34 sec
c. 3 mi 10 sec
300 cGy / 105 cGy per min x 0.875 x 1.029 = 3.17 minutes
60 sec x .17 minutes = 10.2 = 3 min 10 sec
A pt is usually treated at 100cm SSD. The pt must be treated on a stretcher at 135cm SSD. For the tumor dose and size treatment area to remain the same as originally planned, which of the following statements is true?
- The collimator setting will decrease
- The monitor unit setting will increse
- The exit dose will slightly increase
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
A dose of 200 cGy is to be deliered at a depth of 10cm at 100 SAD, from a single 15 x 15 cm filed with 6 mV x-rays. Given the info below, what would the treatment MU be?
TMR (15 x 15 cm, d 10 cm) = 0.806
Output in air, 100 SAD, 15 x 15 cm filed size = 1.015 cGy/mu
BSF (15 x 15 cm) = 1.044
PDD (100 SSD, 15 x 15 cm, d 10 cm) = 72.2%
a. 234 MU
b. 245 MU
c. 251 MU
d. 273 MU
a. 234 MU
MU = Dose/ TMR x Output x BSF
200 cGy / (0.806)(1.015)(1.044)
234 MU
The depth of maximum dose is most dependent on:
a. SSD
b. Field size
c. Beam energy
d. thickness of tissue
c. Beam energy
A 3.5 cm block on a blocking tray 45 cm from the source will block what width at 100 cm?
a. 4.80 cm
b. 5.20 cm
c. 6.01 cm
d. 7.78 cm
d. 7.78 cm
3. 5 x 100= 350
350/45
= 7.78
Why is a tumor of the parotid gland frequently treated with ipsilateral beam arrangements?
a. to avoid th espine
b. to avoid the eyes
c. to avoid the other parotid
d. for ease of setup
c. to avoid the other parotid
What is the theapeutic ratio if the normal tissue tolerance is 5000 cGy and the lethal dose for the tumor is 4000 cGy?
a. 0.80
b. 1.25
c. 1.56
d. 2.10
b. 1.25
normal tissue tolerance / lethal dose
5000/4000
Backscatter factors are independent of:
a. Field size
b. Radiation quality
c. SSD
d. TAR at dmax
c. SSD
A pt was mistakenly treated at 90 cm SSD instead of 100 cm due to a misaligned ODI. The prescried dose was 2.5 Gy. What did the pt actually received?
a. 2.03 Gy
b. 2.77 Gy
c. 3.09 Gy
d. 3.76 Gy
c. 3.09 Gy
(initial dist / new distance)² x prescribed dose
(100 / 90)² x 2.5 Gy
Areas outside the target that receives a higher dose than specified target dose are called:
a. Max taget area
b. Irridiated volume
c. Hot spots
d. Treated volume
c. Hot spots
A treatment time of 2.0 min requires that you add a wedge with a factor of 0.5, what will be the new treatment time?
a. 1.0 min
b. 2.0 min
c. 2.5 min
d. 4.0 min
d. 4.0 min
2. 0 min / 0.5 = 4.0
Find the equivalent square of the resultant field of an 12 x 12 field with a 4 x 6 block:
a. 8.0 x 8.0
b. 9.0 x 9.0
c. 10.0 x 10.0
d. 11.0 x 11.0
d. 11.0 x 11.0
sq root of (12 x 12) - (4 x 6)
= 11 x 11 cm
A pt is 20 cm thick. You are to give 3000 cGy to midline weighted 2:1 / right to left. The %DD for a depth of 10 cm is 0.641. What is the given dose to the left side?
a. 1560 cGy
b. 2340 cGy
c. 3120 cGy
d. 4680 cGy
a. 1560 cGy
1000 cGy per dose (bc 3 fields, 3000/3=1000)
dose per filed/ %DD 1000 cGy/ 0.641
= 1560 cGy
A treatment of 137 monitor units requires that a blocking tray factor of 0.963 be included in the calculation. What are the correct treatment monitor units if the tray is added?
a. 132 MU
b. 137 MU
c. 142 MU
d. 150 MU
c. 142 MU
MU / blocking tray factor
137 MU / 0.693
If a pt received a tumor dose of 250 cGy per day at the 79.2% dd, what is the daily maximum subcutaneous dose?
a. 198 cGy
b. 250 cGy
c. 316 cGy
d. 405 cGy
c. 316 cGy
dose per day / %DD
250 cGy / 0.792
= 316 cGy
A pt’s prescription require a total of 180 cGy to be delivered per day to equally wighted POP fields. The treatment time to deliver 100 cGy is 2.15 min. What treatment time must be delivered to each field to follow the prescription?
a. 0.87 min
b. 1.94 min
c. 2.15 min
d. 405 min
b. 1.94 min
2. 15 min / time x 100 / 180
= 3.87
3.87 / 2 fields (POP) divide
= 1.94 min
What precautions should be taken when treating the chest of a pt witha pacemaker?
- Cover the region of the pacemaker with lead
- Keep the pacemaker out of the direct beam, if possible
- Contact the manufacturer regarding radiation tolerance
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
The largest salivary gland in the H&N is the:
a. Submaxillary
b. Sublingual
c. Parotid
d. Mastoid
c. Parotid
When performing a CT on a pt for IMRT treatment of a prostate, what size slices are used through the true pelvis?
a. 5 mm
b. 3 mm
c. 1 mm
d. 10 mm
b. 3 mm
The practial range for 18 MeV electrons is:
a. 6 cm
b. 8 cm
c. 9 cm
d. unable to determine
c. 9 cm
for practical range divide by 2 or multiply by 1/2
When treating with orthovoltage x-rays, the percentage depth dose will increase with all of the following EXCEPT:
a. increasing field size
b. increasing kV
c. increasing mV
d. increasing distance
c. increasing mV
A pt is accidentally treated at 78 cm SSD, instead of 80 cm SSD. The treatment depth is 3 cm. If the prescribed tumor dose is 200 cGy through a single field, what dose did the tumor actually received?
a. 190 cGy
b. 198 cGy
c 205 cGy
d. 210 cGy
d. 210 cGy
Inv Sq Law
(old dist/new dist)² x orig dose rate
(80 / 78 )² x 200 cGy
210 cGy
The most common presentation of Superior Vena Cava Syndrome is:
a. Distended veins in the head and neck
b. Bloody nasal discharge
c. Headaches
d. Incontinence
a. Distended veins in the head and neck
For pt’s w bladder cancer the bladder should be ______ during treament, when the entire bladder is the target bolume.
Empty
For BOOST bladder may be full
The rapid fall off of dose around a cesium 13 source in a 5 cm radius of tissue is due primarily to:
- the inverse sq law
- the low energy of the radiation
- Alpha and beta emission
a. 1 only
b. 2 only
c. 3 only
d. 1, 2, and 3
a. 1 only
When manipulating a CT image, increasing the width of the window:
- decreases contrast
- increases latitude
- increases speed
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
a. 1 and 2 only
What is the TD 5/5 tolerance dose for both whole lungs given in fractions of 180 cGy/day?
a. . 1500-2500 cGy
b. 2500-3500 cGy
c. 3500-4500 cGy
d. 4500-5000 cGy
a. 1500-2500 cGy
The amount of energy transfered to a material per unit length of travel is termed:
a. RBE
b. LET
c. QF
d. OER
b. LET
What is the TD 5/5 tolerance dose for the whole kidney given in fractions of 180 cGy/day?
a. 1500-2000 cGy
b. 2000-2500 cGy
c. 2500-3000 cGy
d. 3000-3500 cGy
b. 2000-2500 cGy
What is the dose at which you generaly reduce the field “off cord” when treating a H&N cancer?
a. 3000-3500 cGy
b. 4500-5000 cGy
c. 5500-6000 cGy
d. 6000-3500 cGy
b. 4500-5000 cGy
RBE is dependent on which of the following:
- Radiation quality
- Raidation dose per fraction
- Tissue irradiated
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
When dealing with OER and anoxic tissue, which would be the most effective?
a. 6 mV photons
b. Protons
c. Neutrons
d. Electrons
b. Protons
What normal organ would be at most risk when treating a maxillary sinus tumor?
a. Oral cavity
b. Pituitart gland
c. Eye
d. Ear
c. Eye
A pt is set up on a wing board with both arms up. What areas are commonly treated using this position?
- Breast
- Lung
- Pancreas
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3
d. 1, 2, and 3
d. 1, 2, and 3
What is the most potent chemical modifier of radiosensitivity to X and gamma rays?
a. 5 FU
b. Oxygen
c. Misonidazole
d. Adriamycin
b. Oxygen
A pt was treated with a 20 cm long field and a 15 cm long field is matched to it. Both fields are set at 80 SSD. What is the gap on the skin if the fields are to be matched at 10 cm depth?
a. 0.9 cm
b. 1.3 cm
c. 1.8 cm
d. 2.2 cm
d. 2.2 cm
1/2 x depth [( L1 / SSD1) + ( L2 / SSD2)]
1/2 x 10 [( 20 / 80) + ( 15 / 80)]
5 ( 0.4375 )
2.2
When a pt has been treated with a cesium insertion for cervical cancer, why would she be treated with external beam radiaiton following the cesium?
a. To decrease the size of the tumor
b. To deliver a higher dose to the cervix
c. To avoid infertility
d. to treat the pelvic lymph nodes
d. to treat the pelvic lymph nodes
A pt is treated with a 8x15 cm filed, Co-60 unit, 80 cm SSD to a depth of 5cm, 78.5%DD. What would the %DD be if the SSD was changed to 100 cm?
a. 76.9%
b. 80.1%
c. 90.2%
d. 96.1%
b. 80.1%
MF=(SSD1 + d / SSD1 + dmax)² x (SSD2 + dmax / SSD2 + d)²
dmax of Co-60 = 0.5
(80 + 5 / 80 + 0.5)² x (100 + 0.5 + 100 + 5)²
= 1.02……
MF x %DD 1.02…… x 0.785 = .801 = 80.1%
A pt thickness is measured to be 20 cm anterior to posterior. If the pt is brought to an SSD of 90 cm on a 100 cm SAD accelerator, what should a ruler read from the tabletop to isocenter? Assume the pt is flat on the table.
a. 10 cm
b. 15 cm
c. 20 cm
d. cannot determine from info
a. 10 cm
Which of the following is requred for fabrication custom cut blocks?
- SAD
- Source Image Distance
- Source to block tray distance
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
b. 2 and 3 only
The collimator on a linear accelerator are calibrated for a distance of 100 cm. To obtain a field size of 30cm x 30cm at 80cm, what collimator setting is required?
a. 26.7cm x 26.7cm
b. 30cm x 30cm
c. 37.5cm x 37.5cm
d. 41cm x 41cm
c. 37.5cm x 37.5cm
100 x 30 = 3000
3000/80
=37.5
When treating a lesion on the ouside of the nose with electrons, what is the major reason that you place a wax coated lead strip in the nose?
a. to increae the dose on the ouside of the nose
b. to decrease the dose to the inside of the nose
c. for pt comfort
d. a lead strip should neverbe placed within the nose
b. to decrease the dose to the inside of the nose
A dose of 3000 cGy is delivered to a depth of 8cm at PDD of 76%. What is the dose to an underlying organ at 14cm at a PDD of 58%?
a. 5172 cGy
b. 2289 cGy
c. 3947 cGy
d. 4231 cGy
b. 2289 cGy
3000 cGy / 0.76
= 3947
3947 cGy x 0.58 = 2289
Assume a HVL of PB = 3mm. How thick would the lead have to be to reduce exposure of 100 mR at 4 meters to 100 mR at one meter?
a. 12mm
b. 9mm
c. 6mm
d. 3mm
a. 12mm
A pt is to be treated isocentrically to his midline on the 6 MV linear acelerator at 100cm SAD. Calipers have measured the pt thickness to be 21cm. The pt is positioned flat on the table top. What SSD is required for isocentric tretment to the pt’s midline?
a. 79cm
b. 89.5cm
c. 100cm
d. 110.5cm
b. 89.5cm
separation is 21 cm so 10.5 cm to midline
100-10.5 = 89.5cm
The output of a Co-60 teletherapy unit is 85cGy/min in air at 80.5cm for an 11x11cm field. The BSF for this field is 1.10. Calculate the time necessary to deliver a dose of 170 cGy at a depth of 8cm, 80 SSD. The PDD for 11x11 filed at a depth of 8cm is 63%.
a. 2.06 min
b. 2.53 min
c. 2.89 min
d. 3.46 min
c. 2.89
Two wedges are used to treat a maxillary antrum tumor through an anterior and lateral port. What part of the wedges should be adjacent?
a. Thin side anerior to thick side laterally
b. Thin side anterior to thin side laterally
c. Thick side anterior to thick side laterally
d. Thick side anterior to thin side laterally
c. Thick side anterior to thick side laterally
When treating the breast, if a slant board is used rather than the pt lying flat, which of the following is true?
a. The breast “falls” into the supraclavicular port
b. More lung tissue is included in the supraclavicular port
c. It is more difficult for the pt to raise her arm
d. The chest wall cannot be treated when the slant board is used.
b. More lung tissue is included in the supraclavicular port
To verify that the radiation field and the light field are aligned on a 10 MV linear accelerator you could use the following:
a. Tissue equivalent phantom and an ionization chamber
b. Mechanical distance indicator and paper
c. A shielding block and readi-pak x-ray film
d. Readi-pak x-ray film, a pen and a ruler
d. Readi-pak x-ray film, a pen and a ruler
Caculate the MUs to deliver 200 cGy to the 90% isodose line using 12 MeV electrons at 100 SSD if the measured output for the cone and cutout is 0.787 cGy/MU at 100 SSD.
a. 225 MU
b. 229 MU
c. 282 MU
d. 301 MU
c. 282 MU
dose / IDL x output
200 cGy / 0.90 x 0.787 cGy/MU
= 282 MU
A pt is receiving a 300 cGy per day to a spinal cord lesion at 89.5 %DD. What is the dialy given dose at dmax?
a. 269
b. 335
c. 400
d. not enough info to calculate
b. 335
dose / %DD
300 cGy/ .895
= 335 cGy
For photon energies between 0.150 MeV and 10.0 MeV, the predominant type of interaction is:
a. Photoelectric
b. Compton
c. Pair Production
d. Bremsstrahlung
b. Compton
All of the following data was obtained using a 15x15 cm field size at 100 SAD. The dose at dmax in tissue is 280 cGy. The BSF is 1.031 and the TMR at a depth of 12cm is .721. Find the dose delivered at 12cm depth through a single 15x15 cm filed at 100 SAD.
a. 388 cGy
b. 208 cGy
c. 202 cGy
d. 196 cGy
c. 202 cGy
dose at dmax x TMR
280 cGy x .721
= 202
BSF is a distractor
Which of the following systems must be functioning in order to treat a pt safely on a high energy machine?
- A two-way audio system
- A visual system to monitor the pt and machine function
- an audible signal to inform the pt when the machine is on
a. 1 and 2 only
b. 1 and 3 only
c. 2 and 3 only
d. 1, 2, and 3
a. 1 and 2 only
To preserve the skin sparing properties of the megavoltage photon beams, the compensator is placed at least ____ from the skin.
a. 1-5 cm
b. 5-10 cm
c. 9-12 cm
d. 15-20 cm
d. 15-20 cm
The PDD for a 12x12 cm filed, 6 MV, 5 cm depth at 80 cm SSD is 82.8%. Calculate the PDD for he same field size and depth for 100 cm SSD.
a. 81.4%
b. 82.1%
c. 83.4%
d. 84.2%
d. 84.2%
MF=(SSD1 + d / SSD1 + dmax)² x (SSD2 + dmax / SSD2 + d)²
dmax for 6MV= 1.5
MF= (80 + 5 / 80 + 1.5)² x (100 + 1.5 / 100 + 5)²
MF= 1.09 x .934
MF = 1.01
MF x PDD
1.01806 x 0.828
= 0.842
= 84.2%
What is the main advantage of using Cerrobend over lead in custom blocking?
a. It is softer than lead
b. It cannot form air bubbles
c. It has a lower melting point
d. It requires thicker blocks to obtain the same effect
c. It has a lower melting point
Portal verification is defined as the documentation of:
a. Isodose curves through teh use of ilm or eletronic imaging devices
b. The extent of diseae using film or electronic imaging devices
c. The actual treatment using film or electronic imaging devices
d. The approval of the treatment port by a qualified physician
c. The actual treatment using film or electronic imaging devices
The pt is positioned supine and is to be treated using an isocentric technique. The AP SSD reads 88cm and you move the iscenter 2cm posterior only. What should the SSD read?
a. 86cm
b. 88cm
c. 90cm
d. unable to determine
a. 86cm
The pt is positioned supine and is to be treated using an isocentric technique. The AP SSD reads 84cm. If the pt’s thickness is 36cm, what is the PA SSD?
a. 64cm
b. 80cm
c. 84cm
d. 88cm
b. 80cm
According to the ICRU termiology, the area that is defined as the palpable or visible extent of the malignant tumor is called the:
a. Treated volume
b. Gross tumor volume
c. Clinical target volume
d. Planning target volume
b. Gross tumor volume
What is the tolerance dose for the outlined organ in MRI image?
a. 2500-3000 cGy
b. 3000-3500 cGy
c. 4500-5000 cGy
d. 6000-6500 cGy
c. 4500-5000 cGy
Calculate the dose at dmax if 200 cGy is delivered to 7cm below the skin at the 72 %DD.
a. 144 cGy
b. 197 cGy
c. 206 cGy
d. 278 cGy
d. 278 cGy
dose / %DD
200 cGy / .72
278 cGy
A lung lesion is being treated using POP isocentic ports with teh patient in the supine position. The physician wants to place the isocenter at the pt’s midline. The ruler placed on the table top reads 30cm from the table tot he pt’s anterior surface. There is a 1.5 cm immobilization device between the pt and the table. What is the pt’s total thickness?
a. 30cm
b. 28.5cm
c. 14.3cm
d. unable to determine
b. 28.5cm
The collimator setting is 8x10cm on a 100cm SAD machine. The SSD on the pt’s skin reads 90cm. What is the field size on the pt’s skin.
a 7.2x9cm
b. 8x10cm
c. 8.9x11.1cm
d. unable to determine
a 7.2x9cm
direct proportion
You have an extremely large pt and you must treat two lateral pelvic fields. What technique will give you the most even dose distribution throughout the treatment field?
a. Isocentric technique treated to the pt’s midline
b. SSD technique, moving the treatment table as far away from the source as possible
c. Midline isocentric technique with blocks added
d. Midline isocentric with wedges added
b. SSD technique, moving the treatment table as far away from the source as possible
A pt is treted on teh 6 MV linear accelerator. The pt is set up to 94cm SSD. The TAR at 6cm depth is 0.87 and the output at isocenter in air is 1.02 cGy/MU for the required field size. How many MUs will it take to deliver 100 cGy to a depth of 6cm?
a. 88 MU
b. 102 MU
c. 113 MU
d. 116 MU
c. 113 MU
dose / output x TAR
100 cGy / 1.02 cGy per MU x 0.87
= 113 MU
A treatment designed to be given at 100 SSD is mistakenly given at 94 SSD. What is the error in dose delivered?
a. 13% overdose
b. 13% underdose
c. 6% overdose
d. 6% underdose
a. 13% overdose
(100/94)² = 1.13
13 overdose bc is closer to source
When a field size is changed during the course of a pt’s treatement, which of the following statements are TRUE?
- Treatment depth must change
- The physician must include changes in the prescription
- The MU or time must be recalculated
a. 1 and 2 only
b. 1 and 3 only
c. 2 and 3 only
d. 1, 2, and 3
c. 2 and 3 only
All chemicals used in a department require:
a. Listing with the human resourse dept
b. Material safety data sheets (MSDS)
c. An 800 number for toxic info
d. Labels containing infor in case of exposure
b. Material safety data sheets (MSDS)
The standard amount of time that should elapse between two radiation therapy treatments given in the same day to the same site is:
a. 3 hrs
b. 6 hrs
c. 9 hrs
d. 12 hrs
b. 6 hrs
If 1.5cm is added to the inferior border of a treatment port, what happens to the original isocenter if you are not using independent (asymetric) jaws?
a. shifts 0.75cm superiorly
b. shifts 0.75cm inferiorly
c. Shifts 1.5cm superiorly
d. Isocenter stays the same
b. shifts 0.75cm inferiorly
Which of the following statements concerning a pt’s rights are TRUE?
- A relative has the right to access a pt’s record
- The pt has the right to refuse treatment
- The pt has the right to be informed of any alternative procedures prior to his treatment
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
b. 2 and 3 only
MV portal films taken on a megavoltage machine have less contrast than kV films because the MVimage results principally from:
a. Pair Production
b. Photoelectric
c. Compton interaction
d. Photodisintegration
c. Compton interaction
Restraining a pt in an aquaplast mask without concent can be considered:
- Battery
- Assault
- Humane
a. 1 and 2 only
b. 2 and 3 only
c. 3 only
d. 1, 2, and 3
a. 1 and 2 only
During radiation therapy to the pelvis if a pt is complaining of the following, which would most likely warrant interruption in the course of treatment:
a. Dysuria
b. Acute radiation enteritis
c. Tenesmus
d. Impotence
b. Acute radiation enteritis
Which of the following is TRUE concerning a pt’s medical record?
- It is a legal public doc
- Pt’s may review their record upon request
- It may be subpoenaed into a court of law
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3 only
d. 1, 2, and 3 only public?? ask
The deficiency in the number of circulating WBCs in the body is called:
a. Anemia
b. Leukopenia
c. Polycythemia
d. Thrombcytomenia
b. Leukopenia
After what time period would fibrosis generally appear following standard external therapy?
a. one month
b. one year
c. one week
d. two weeks
b. one year
When treating the parotid gland with standard fractionation (180-200 cGy/day), what is the TD 5/5 that pt’s will develop xerostomia?
a. 500-1500 cGy
b. 2500-3500 cGy
c. 4500-5500 cGy
d. 6500-7500 cGy
b. 2500-3500 cGy
The most common long term effect of radiaiton therapy to the lung is:
a. Pneumonitis
b. Necrosis
c. Fibrosis
d. Esphagitis
c. Fibrosis
When treating a pt with glioblastoma, he begins to experience nausea, dizziness, and blurred vision. Which is the most likely reason?
a. tumor necrosis
b. cerebral edema
c. CNS syndrome
d. Reaction to medication
b. cerebral edema
Deodorants should not be used on the skin within a radiation treatment field bc the deodorants will:
a. create scatter radiation
b. act as bolus
c. enhance the radiation
d. irritate sensitive skin
d. irritate sensitive skin (on mosby right answer was b) ask
Written defamation of character is best known as:
a. Slander
b. Libel
c. Cursing
d. Literary fault
b. Libel
The normal platelet count is approx:
a. 60,000 cc
b. 80,000 cc
c. 120,000 cc
d. 300,000 cc
d. 300,000 cc
All of the following meds are antimetics except:
a. Norazine
b. Compazine
c. Tylenol
d. Torecan
c. Tylenol
Bone marrow depression is most likely to occur when you are treating which part of the body?
a. skull
b. pelvic bones
c. femur
d. vertebrae
b. pelvic bones
Which of the following chemotherapeutic drugs sensitizes the human heart?
a. Bleomycin
b. Adriamycin
c. Vincristine
d. Cis-platinum
b. Adriamycin
When treating the whole brain which drug is used to reduce radiation induced edema?
a. Antibiotics
b. Corticosteroids
c. Diuretics
d. Antihistamines
b. Corticosteroids
Pts who are neutropenic frequently present with ______ due to this condition.
a. headaches
b. shortness of breath
c. bleeding
d. infections
d. infections
Which of the following types of medical apparatus should normally remain at a level above the pt at all times?
a. chest tubes
b. suction aparatus
c. IV infusion equipment
d. urinary drainage equipment
c. IV infusion equipment
Which of the following is NOT a principle of using proper body mechanics?
a. roll or slide objects when possible rather than lift
b. keep the feet close together to provide support
c. avoid twisting or bending at the waist
d. lift objects with knees fixed
b. keep the feet close together to provide support
Which of the following methods is used to deliver hyperalimentation?
a. oral intake
b. intramuscular injection
c. intravenous injection
d. subcutaneous injection
c. intravenous injection
The purpose of Protective (Reverse) Isolation is:
a. to prevent the transmission of pathogens in the feces
b. to prevent transmission of pathogens transmitted by direct contact with wounds
c. to protect an uninfected pt with lowered resistance
d. to prevent infection personnel
c. to protect an uninfected pt with lowered resistance
Which of the following is the best method to prevent the spread of infection?
a. wash hands
b. wear gloves
c. wear a mask
d. clean the table
a. wash hands
To prevent the spread of airborne droplet infection, which of the following must be employed?
- gowns
- masks
- gloves
a. 1 only
b. 2 only
c. 3 only
d. 1, 2, and 3
b. 2 only
The term that best describes the complete removal of all microorganisms is called:
a. Medical asepsis
b. Disinfection
c. Anisepsis
d. Sterilization
d. Sterilization
A pt with Tuberculosis should be placed in:
a. Enteric isolation
b. Protective isolation
c. Respiratory isolation
d. Reverse isolation
c. Respiratory isolation
Regarding “flatness” of a megavoltage photon beam, which of the following is TRUE?
- Beam flatness changes with depth due to scatter and deceased intensity at the field edge
- Adequate flatness is defined as +/- 3% over 80% of the field at thhe measured depth
- Flatness profiles may be used to determine symmetry
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
During a convulsive seizure, the most important action to be taken by a therapist is:
a. Prevent pt injury
b. Give the pt water
c. Give the pt sugar
d. Hold the pt’s tongue
a. Prevent pt injury
A pt’s separation is 30cm. If the posterior SSD reads 89cm on a 100cm isocentric machine, what should the anterior SSD read?
a. 70cm
b. 81cm
c. 89cm
d. unable to determine
b. 81cm
An iatrogenic infection is one caused by:
a. Hospital employees
b. Synergistic effect with radiation
c. Blood borne pathogens
d. Complications from treatment
d. Complications from treatment
The point of intersection of the collimators and the gantry axis of rotation is the:
a. Midline
b. Isocenter
c. Treatment volume
d. Tumor volume
b. Isocenter
The two major energies associated with Co-60 beta decay are gamma energies of:
a. 1.02 and 1.11 MeV
b. 1.17 and 1.33 MeV
. 2.25 and 2.38 MeV
d. 2.51 and 3.02 MeV
b. 1.17 and 1.33 MeV
The 80% isodose line can be estimated for electrons dividing the energy (E) of:
a. 2.11
b. 2.33
c. 3.00
d. 4.00
c. 3.00
According to the definition of the International Commission on Radiation Units and Measurements (ICRU), the wedge angle refers to: “the angle through which an isodosecurve is titled at the central ray of a beam at a specified depth.” The recommended depth is:
a. 5cm
b. 10cm
c. 15cm
d. 20cm
b. 10cm
If you compare the penumbra of a 6 MV linear accelerator, operating in the photon mode, to the penumbra of a Co-60 teletherapy machine using the same SSD, which of the following is TRUE?
a. The 6 MV linear accelerator has a greater penumbra than the Co-60 source
b. The 6 MV linear accelerator has less penumbra than the Co-60 source
c. The 6 MV linear accelerator has the same penumbra as the Co-60
d. Neither machine would have measurable penumbra
b. The 6 MV linear accelerator has less penumbra than the Co-60 source
PDD increases with:
- Field size
- SSD
- Energy
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
For radiation workers, the occupaaional dose is usually reported in:
a. Rad
b. Rem
c. Roentgen
d. Gray
b. Rem
A localization film was taken at 109cm FFD. A 3.5 cm magnification ring was placed on the pt’s skin. It measures 4.2cm on the film. What distance is the magnification ring from the focal spot?
a. 83.2cm
b. 90.8cm
c. 138cm
d. 147cm
b. 90.8cm
4. 2/3.5= 1.2
109/1.2= 90.8
When a pt is treated with more than one beam, misalignment between parallel opposed beams can occur due to displacement of the:
- Target
- Collimator axis of rotation
- Gantry axis of rotatioon
a. 1 and 2 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2, and 3
d. 1, 2, and 3
Which of the following ha the LEAST radiosensitivity (most resistant)?
a. Bone marrow
b. Lymphoid tissue
c. Muscle
d. Mature cartilage
d. Mature cartilage
Where are pancoast tumors located?
a. Apex of the lung
b. Periphery of the lung
c. Mediastinum
d. Helum
a. Apex of the lung
The most radiosensitive stage of the cell cycle is:
a. DNA synthesis
b. G1
c. G2
d. Mitosis
d. Mitosis
A split beam technique in which half of the field is blocked:
- Prevents beam divergence
- Allows for fileds to match at the centray ray
- Overlays the penumbra of two fields
a. 1 and 2 only
b. 1 and 3 only
c. 2 and 3 only
d. 1, 2, and 3
a. 1 and 2 only
The most common presenting sign of Wilms tumor is:
a. Fever and chills
b. Non-tender mass
c. Bone pain
d. Nausea and vomiting
b. Non-tender mass
In general, when treating with radiation, the proximal and distal margin around a soft tissue sarcoma should be at least _____ cm.
a. 2
b. 5
c. 8
d. 12
b. 5
Where does the spinal cord start and stop in normal adults?
a. Foramen magnum to L5
b. C7 to L5
c. Foramen Magnum to L2
d. Foramen Magnum to T2
c. Foramen Magnum to L2
The practical range of an electron beam:
- Increases with increasing electron energy
- About 1cm for every 2 MeV
- About one half of the electron energy
a. 1 and 2 only
b. 2 an 3 only
c. 1 and 2 only
d. 1, 2, and 3
d. 1, 2, and 3
Mayneord’s F Factor is a correction for which of the following:
a. Depth
b. Field Size
c. Beam Energy
d. Distance
d. Distance
In a 120° arc rotation technique, the center of the high dose zone would be:
a. Deeper than the isocenter
b. Displaced towards the surface
c. Same shape as a 360° rotation
d. At the isocenter
b. Displaced towards the surface
Regarding electron beams which of the following is TRUE:
- Directly ionlizing due to their negative charge
- Less likely to interact with air than photons
- Have a higher LET than photons
a. 1 and 2 ony
b. 2and 3 only
c. 1 and 3 only
d. 1, 2, and 3
c. 1 and 3 only
