Mosby 233 Mock Exam Questions
Perfectly Answered
What is the ratio of dose at depth in tissue to the dose at electronic equilibrium (Dmax) on the beam
axis known as? - ✔ ✔ PDD
What is the TD5/5 for the optic chiasm? - ✔ ✔ 60 Gy
What is the term for a representation of the dose in an irradiated volume as a function of spatial
position along a single line? - ✔ ✔ dose profile
What is the term for blue coloring of skin or nails, observed as a sign of low oxygen content? - ✔ ✔
cyanosis
What is the term for the procedure used in which an implant is made using a trocar, with radioactive
sources introduced into the trocar and then the trocar is removed? - ✔ ✔ interstitial afterloading
What is the threshold dose for radiation pneumonitis? - ✔ ✔ 20-25 Gy
What is the total dose administered to a prophylactic cranial irradiation for ALL? - ✔ ✔ 1800 cGy
What is the transient sensation of electrical shock traveling down the neck and extremities following
radiation to the spine referred to? - ✔ ✔ Lhermitte's sign
What is the tunica albuginea? - ✔ ✔ capsule of white collagenous connective tissue in the ovaries
What is the worst prognosis for a primary skin cancer? - ✔ ✔ melanoma
What is the x,y,z coordinate system used for? - ✔ ✔ describe the location of a point in space relative
to iso
What kind of shock is associated with bacterial infections and its toxic byproducts? - ✔ ✔ septic
shock
What percentage of adenomatous polyps of the colon contains invasive cancer cells? - ✔ ✔ 3-5%
What radiation interaction with matter occurs independently of atomic number? - ✔ ✔ Compton
effect
What relationship does mass attenuation coefficient (µ/p) have with density? - ✔ ✔ independent
What should a therapist do if a chest tube becomes dislodged while moving a patient? - ✔ ✔ apply
an airtight dressing over the opening
,What should the console and control panel for the linac have a visual display of? - ✔ ✔ beam energy,
treatment mode, monitor units, timer, and beam on/off status
What should the therapist do when an immobilization device is determined? - ✔ ✔ consider patient
position, beam orientation, and finally which device
What should the total dose be to a lumpectomy site after accelerated PBI utilizing HDR brachy? - ✔ ✔
40-50 Gy
What technique is used to treat early pre-cancers of the cervix? - ✔ ✔ loop electrosurgical excision
procedure (LEEP)
What thickness of cerrobend would be equivalent to 5cm of lead? - ✔ ✔ 6.0cm
An important risk factor for the development of cervical cancer is: - ✔ ✔ human papilloma virus
(HPV)
Arrange the following X-ray energies in order of increasing PDD penetration: 1) orthovoltage 2) 18 MV 3)
10 MV 4) superficial - ✔ ✔ superficial, orthovoltage, 10MV, 18MV
As overall time of treatment is altered, with fraction size and total dose remaining unchanged, the
biological effect does what? - ✔ ✔ increases as time is shortened
As you're escorting the patient into the room, she begins to collapse. You help her safely to the floor,
what do you do next? - ✔ ✔ responsiveness check (shake patient & shout name)
Before administering IV contrast, it's important to check BUN and Creatinine levels to assure proper
function of what? - ✔ ✔ kidneys
Beyond the point of beam intersection, what would be an advantage of using the wedged pair
technique? - ✔ ✔ rapid dose falloff
**highest dose concentration near hinge of wedge, then rapid falloff
Cells of malignant growth are commonly: 1) anaplastic, 2) well differentiated, 3) slow growing, 4) poorly
oxygenated - ✔ ✔ 1) anaplastic
**when cells lose all order and ability to function normally
Chondrosarcoma originates in what type of tissue? - ✔ ✔ osseous tissue
Clarkson's method is used to determine the scatter produced in what kind of fields? - ✔ ✔ irregular
fields
, Diastolic pressure is the pressure within the arteries that exists while the heart is what? - ✔ ✔
resting
Dose is normalized to what in an SAD technique? - ✔ ✔ treatment depth
Dose is normalized to what in an SSD treatment technique? - ✔ ✔ Dmax
Electron contamination of high energy photon beams may result from photon interactions with what? -
✔ ✔ collimators
Epistaxis is the medical term for what? - ✔ ✔ nosebleed
167 MU were calculated to deliver 100cGy to a tx field including a wedge. Wedge was accidentally
omitted but 167 MU were still used. If wedge factor was 0.752 and TMR was 0.796, what was the actual
dose delivered? - ✔ ✔ 133 cGy
**MU x TMR x WF (but wedge was omitted)
167 x 0.796 = 132.9
1kg is equal to how many pounds? - ✔ ✔ 2.2lbs
A 6MV photon beam on the linac has an output at iso of 1.2 cGy/MU. What would be the inverse square
factor used in the MU cal for an extended distance of 120cm SSD? - ✔ ✔ 0.677
inverse square
(SAD/SSD + Dmax)ˆ2
(100/121.5)ˆ2 = 0.677
A dose of 300 cGy is to be delivered at 95cm SSD, but was delivered at 92cm SSD. What was the actual
dose? - ✔ ✔ 320
I1/I2 = (D2/D1)^2
A high energy photon strikes an orbital electron and scatters exactly 180 degrees. What's the max
energy of the scattered photon? - ✔ ✔ 255 kV
A low residue diet is recommended for patients receiving radiation to what area? - ✔ ✔
abdominopelvic regions
Perfectly Answered
What is the ratio of dose at depth in tissue to the dose at electronic equilibrium (Dmax) on the beam
axis known as? - ✔ ✔ PDD
What is the TD5/5 for the optic chiasm? - ✔ ✔ 60 Gy
What is the term for a representation of the dose in an irradiated volume as a function of spatial
position along a single line? - ✔ ✔ dose profile
What is the term for blue coloring of skin or nails, observed as a sign of low oxygen content? - ✔ ✔
cyanosis
What is the term for the procedure used in which an implant is made using a trocar, with radioactive
sources introduced into the trocar and then the trocar is removed? - ✔ ✔ interstitial afterloading
What is the threshold dose for radiation pneumonitis? - ✔ ✔ 20-25 Gy
What is the total dose administered to a prophylactic cranial irradiation for ALL? - ✔ ✔ 1800 cGy
What is the transient sensation of electrical shock traveling down the neck and extremities following
radiation to the spine referred to? - ✔ ✔ Lhermitte's sign
What is the tunica albuginea? - ✔ ✔ capsule of white collagenous connective tissue in the ovaries
What is the worst prognosis for a primary skin cancer? - ✔ ✔ melanoma
What is the x,y,z coordinate system used for? - ✔ ✔ describe the location of a point in space relative
to iso
What kind of shock is associated with bacterial infections and its toxic byproducts? - ✔ ✔ septic
shock
What percentage of adenomatous polyps of the colon contains invasive cancer cells? - ✔ ✔ 3-5%
What radiation interaction with matter occurs independently of atomic number? - ✔ ✔ Compton
effect
What relationship does mass attenuation coefficient (µ/p) have with density? - ✔ ✔ independent
What should a therapist do if a chest tube becomes dislodged while moving a patient? - ✔ ✔ apply
an airtight dressing over the opening
,What should the console and control panel for the linac have a visual display of? - ✔ ✔ beam energy,
treatment mode, monitor units, timer, and beam on/off status
What should the therapist do when an immobilization device is determined? - ✔ ✔ consider patient
position, beam orientation, and finally which device
What should the total dose be to a lumpectomy site after accelerated PBI utilizing HDR brachy? - ✔ ✔
40-50 Gy
What technique is used to treat early pre-cancers of the cervix? - ✔ ✔ loop electrosurgical excision
procedure (LEEP)
What thickness of cerrobend would be equivalent to 5cm of lead? - ✔ ✔ 6.0cm
An important risk factor for the development of cervical cancer is: - ✔ ✔ human papilloma virus
(HPV)
Arrange the following X-ray energies in order of increasing PDD penetration: 1) orthovoltage 2) 18 MV 3)
10 MV 4) superficial - ✔ ✔ superficial, orthovoltage, 10MV, 18MV
As overall time of treatment is altered, with fraction size and total dose remaining unchanged, the
biological effect does what? - ✔ ✔ increases as time is shortened
As you're escorting the patient into the room, she begins to collapse. You help her safely to the floor,
what do you do next? - ✔ ✔ responsiveness check (shake patient & shout name)
Before administering IV contrast, it's important to check BUN and Creatinine levels to assure proper
function of what? - ✔ ✔ kidneys
Beyond the point of beam intersection, what would be an advantage of using the wedged pair
technique? - ✔ ✔ rapid dose falloff
**highest dose concentration near hinge of wedge, then rapid falloff
Cells of malignant growth are commonly: 1) anaplastic, 2) well differentiated, 3) slow growing, 4) poorly
oxygenated - ✔ ✔ 1) anaplastic
**when cells lose all order and ability to function normally
Chondrosarcoma originates in what type of tissue? - ✔ ✔ osseous tissue
Clarkson's method is used to determine the scatter produced in what kind of fields? - ✔ ✔ irregular
fields
, Diastolic pressure is the pressure within the arteries that exists while the heart is what? - ✔ ✔
resting
Dose is normalized to what in an SAD technique? - ✔ ✔ treatment depth
Dose is normalized to what in an SSD treatment technique? - ✔ ✔ Dmax
Electron contamination of high energy photon beams may result from photon interactions with what? -
✔ ✔ collimators
Epistaxis is the medical term for what? - ✔ ✔ nosebleed
167 MU were calculated to deliver 100cGy to a tx field including a wedge. Wedge was accidentally
omitted but 167 MU were still used. If wedge factor was 0.752 and TMR was 0.796, what was the actual
dose delivered? - ✔ ✔ 133 cGy
**MU x TMR x WF (but wedge was omitted)
167 x 0.796 = 132.9
1kg is equal to how many pounds? - ✔ ✔ 2.2lbs
A 6MV photon beam on the linac has an output at iso of 1.2 cGy/MU. What would be the inverse square
factor used in the MU cal for an extended distance of 120cm SSD? - ✔ ✔ 0.677
inverse square
(SAD/SSD + Dmax)ˆ2
(100/121.5)ˆ2 = 0.677
A dose of 300 cGy is to be delivered at 95cm SSD, but was delivered at 92cm SSD. What was the actual
dose? - ✔ ✔ 320
I1/I2 = (D2/D1)^2
A high energy photon strikes an orbital electron and scatters exactly 180 degrees. What's the max
energy of the scattered photon? - ✔ ✔ 255 kV
A low residue diet is recommended for patients receiving radiation to what area? - ✔ ✔
abdominopelvic regions
