Deck 17: Intensity-Modulated Radiation Therapy

Question 1

Dose escalation refers to:

A) delivery of higher doses of radiation than those traditionally administered
B) delivery of higher dose to the surrounding tissue than the tumor dose
C) delivery of a high dose to a small treatment volume
D) delivery of a lower dose of radiation than traditionally prescribed

Answer 1

A
Dose escalation refers to the delivery of higher than traditional doses to a treatment volume.Dose escalation has shown good tumor control with a reduction of complications to normal tissue and organs at risk due to their proximity to the tumor site.

Question 2

Intensity-modulated radiation therapy (IMRT)is an advanced form of:

A) OAR
B) PET
C) 3D
D) 3D CRT

Answer 2

D
The process by which external beams of radiation are designed and used to selectively and exclusively irradiate only tumor-bearing sites is called three-dimensional conformal radiation therapy (3D CRT).IMRT is an advanced form of 3D CRT.

Question 3

Errors in treating small positional anatomic sites are more critical in:

A) treatment planning process
B) conventional treatment techniques
C) IMRT treatments
D) 3D treatments

Answer 3

C
Because small positional errors may affect the treatment outcome more with IMRT than with conventional radiation therapy,special attention is needed in the construction and positioning of such devices in an effort to increase treatment reproducibility.

Question 4

Intensity-Modulated Radiation Therapy (IMRT)can only be used with multileaf collimators (MLCs).

Question 5

The two most common approaches in treatment planning are:

A) IMRT with multileaf collimators (MLCs)
B) forward and inverse planning
C) dose escalation and dose histograms
D) PET scans and beam's-eye view treatment plans

Question 6

Biologic imaging uses which of the following technologies?

A) PET scans
B) PET scans using fluorodeoxyglucose
C) CT scan with and without contrast
D) MRI with postcontrast enhancement

Question 7

The major advantage of IMRT over conventional 3D CRT treatment techniques is that:

A) IMRT delivers a higher dose to the surrounding structures.
B) IMRT delivers a uniform dose to both tumor volume and surrounding structures.
C) IMRT delivers a variable tumor dose from each treatment field.
D) IMRT delivers a conformal dose of varying beam intensities.

Question 8

The term fluence pattern refers to:

A) the shoulder of dose-response curve use for treatment planning purposes
B) intensity pattern of the IMRT beam
C) intensity patterns of 3D treatment planning
D) intensity patterns of 3D treatment plans

Question 9

Step and shoot is a form of IMRT that:

A) uses compensators in delivery of the radiation dose
B) can be used in a static or dynamic mode
C) can be used in a dynamic mode only
D) can be used in a static mode only

Question 10

For years,conventional radiation therapy techniques attempted to produce a homogeneous radiation beam within the patient using:

A) beam compensators and wedges
B) 3D treatment plans
C) CT-generated treatment plans
D) multileaf collimators (MLCs)

Question 11

Gantry rotation combined with dynamically programmed MLCs is termed:

A) sliding window IMRT
B) step and shoot IMRT
C) intensity-modulated arc therapy
D) segmental IMRT

Question 12

Which of the following treatment planning systems or techniques is accomplished by selecting an optimal dose?

A) inverse treatment planning
B) forward treatment planning
C) direct treatment planning
D) indirect treatment planning

Question 13

The major key to the precision delivery of radiation to the exact tumor volume begins with:

A) accurate CT images
B) simulation process
C) accurate dose escalation measurements
D) proper sequencing of multileaf collimators (MLCs)

Question 14

Advances in 3D imaging have contributed greatly to the treatment planning process due to:

A) more sophisticated 3D imaging data
B) the improved precision of 3D imaging
C) the reformatting of digital data from CT and MRI
D) none of the above

Question 15

Conformal therapy treatment techniques and segmenting are both attributed to:

A) 3D
B) MLCs
C) wedges and compensators
D) 3D CRT

Question 16

Conformal radiation therapy (CRT)techniques use:

A) 3D
B) 3D CRT
C) CT images only
D) 3D,CRT and IMRT

Question 17

Some institutions use forward IMRT treatment planning frequently for radiation therapy treatments of the:

A) lung
B) liver
C) prostate
D) colon

Question 18

TomoTherapy may also be referred to as:

A) fan beam intensity modulation
B) image-guided radiation therapy
C) sliding window IMRT
D) step and shoot IMRT

Question 19

Contouring can best be described as:

A) drawing of beam symmetry
B) accurate delineation of tumor volume and surrounding structures
C) a process for dosimetric verification
D) treatment information routing

Question 20

IMRT,when administered with physical modulators,is:

A) the most complex of all IMRT methods
B) considered to be the simplest method of IMRT
C) is not considered a form of conformal radiation therapy (CRT)
D) performed with multiple wedges