Radiation Therapy Treatment Planning
Help!
|
|
||||
|---|---|---|---|---|---|
| Radiation Therapy prescription | show 🗑
|
||||
| show | Defines the treatment volume, intended tumor dose, number of treatments, dose per treatment, and frequency of treatment. Also stated are the type and energy of radiation to be used, beam-shaping devices and any other appropriate factors (W/L, pg. 493).
🗑
|
||||
| show | Refers to the energy deposited at a specific point in a medium. The dose is measured at a specific point (in a patient or phantom) and is commonly measured in Gray (Gy). (W/L, pg. 493).
🗑
|
||||
| Depth | show 🗑
|
||||
| show | The measurement of the patient’s thickness from the point of beam entry to the point of beam exit (W/L, pg. 494).
🗑
|
||||
| show | The distance from the source of photons to the patient’s skin surface (W/L, pg. 494).
🗑
|
||||
| SAD | show 🗑
|
||||
| show | The intersection of the axis of rotation of the gantry and the axis of rotation of the collimator for the treatment unit (W/L, pg. 494).
🗑
|
||||
| Field Size | show 🗑
|
||||
| Depth of Maximum Equilibrium (Dmax) | show 🗑
|
||||
| Output | show 🗑
|
||||
| Output Factor | show 🗑
|
||||
| show | Gap = (L1/2 × d/SSD1) + (L2/2 × d/SSD2) (W/L, pg. 516).
🗑
|
||||
| show | Given Dose= (TD/PDD) × 100 (W/L, pg. 509).
🗑
|
||||
| Tumor Dose (Dmax Dose) | show 🗑
|
||||
| Mayneord F-factor | show 🗑
|
||||
| Inverse Square Law | show 🗑
|
||||
| show | Equivalent Square= (4(L ×W)) / (2(L +W)) (W/L, pg. 498).
🗑
|
||||
| show | ISCF = (Reference distance + Dmax)^2 / (Treatment distance + Dmax)^2 (W/L, pg. 508).
🗑
|
||||
| show | ISCF = (Reference source calibration distance)^2 / (Treatment SSD +Dmax)^2
*(Reference source calibration distance = Reference distance + Dmax for the energy) (W/L, pg. 508).
🗑
|
||||
| show | (Reference distance / Source Calculation Point Dose [SCPD])^2
*Reference distance = 100; SCPD = The set up SSD + Depth (W/L, pg. 508).
🗑
|
||||
| show | MU/Time=(Prescribed Dose)/
(RDR*ISCF*Sc*Sp*PDD/100*Other)
(W/L, pg. 504)
🗑
|
||||
| Monitor Unit Calculations for SAD (Isocentric) Set-ups (TAR) | show 🗑
|
||||
| Monitor Unit Calculations for SAD (Isocentric) Set-ups (TMR) | show 🗑
|
||||
| show | MU= (Prescribed Dose) / (RDR×ISCF×Sc×Sp×TPR×Other factors) (W/L, pg. 511).
🗑
|
||||
| show | HA = 180 - 2(wedge angle) (RT Essentials, pg. 135)
🗑
|
||||
| Wedge Angle | show 🗑
|
||||
| Electron Beam Mean Energy | show 🗑
|
||||
| Practical Range (Er) in cm Electron Beam in Tissue | show 🗑
|
||||
| show | MeV/3 (W/L, pg. 555).
🗑
|
||||
| Electron 90% Isodose line | show 🗑
|
||||
| show | A = (0.66mg/cm) x (active length of source in cm)
🗑
|
||||
| Activity Half Strength Source | show 🗑
|
||||
| show | 200 cGy/3 = 66.7 cGy
AP = 66.7 x 2 = 133.4 cGy.
PA = 66.7 x 1 = 66.7 cGy.
🗑
|
||||
| Patient is to be treated with total dose of 180 cGy in a four field arrangement AP, PA, RL and LL (2:1:1.5:1.5). What is the dose to each field? | show 🗑
|
||||
| show | (17/2 x 3/92) + (15/2 x 3/91)
(8.5 x .0326) + (7.5 x .0324)
(.2771 + .0243)
Gap= .52
🗑
|
||||
| show | 9 X 25; 1.33 x 7 cm = 9.31 cm; 1.33 x 19 cm = 25.27 cm
🗑
|
||||
| A patient has a tumor 3.5 cm wide at a depth of 4 cm. What will be the necessary field width at the skin surface to cover the tumor volume plus a 1 cm margin on each side using a linear accelerator and isocentric set-up? | show 🗑
|
||||
| The dose rate on a linear accelerator is 102.4 cGy/Min at 100 cm. What is the dose rate at 85.5 cm? | show 🗑
|
||||
| The optimum hinge angle for a 60 degree wedge would be: | show 🗑
|
||||
| show | (10/2 x 5/100) + (15/2 x 4/100); Gap= .55cm.
🗑
|
||||
| Calculate the equivalent square for a field size of 10 cm X 15 cm. | show 🗑
|
||||
| What are the 80% and 90% isodose lines for a patient treated with a 16 MeV electron beam? | show 🗑
|
||||
| show | (300 x 87.9)/100 = 263.7 cGy. (See Table 24-6 W/L pg. 519)
🗑
|
||||
| show | 180/0.60 = 300 cGy.
🗑
|
||||
| show | Hinge Angle.
🗑
|
||||
| A 45 degree wedge is inserted into a field to modify the isodose curve. The toe section will allow (greater or lesser) intensity in part of the beam. | show 🗑
|
||||
| show | Heterogeneity Corrections.
🗑
|
||||
| Palpable tumor; visible areas of known disease. | show 🗑
|
||||
| show | PTV.
🗑
|
||||
| The area enclosed by the isodose surface selected. | show 🗑
|
||||
| Contains a margin for subclinical extensions of the disease. | show 🗑
|
||||
| show | 2 cm superior and 2 cm lateral to the center of the cervical os.
🗑
|
||||
| show | Smaller.
🗑
|
||||
| show | Cesium-137 (W/L, pg. 303).
🗑
|
||||
| show | Iridium-192 (W/L, pg. 305).
🗑
|
||||
| What is the half-life of radium-226? | show 🗑
|
||||
| What is the half-life of cobolt-60? | show 🗑
|
||||
| show | 30.0 years (W/L, pg. 303).
🗑
|
||||
| show | 73.83 days (W/L, pg. 303).
🗑
|
||||
| What is the half-life of iodine-125? | show 🗑
|
||||
| show | 16.99 days (W/L, pg. 303).
🗑
|
||||
| What is the half-life of gold-198? | show 🗑
|
||||
| What is the half-life of radon-222? | show 🗑
|
||||
| show | 35/100 = x/115; 40/100 = y/115;
100x = 4025; 100y = 4600;
x = 40.25 y = 46
🗑
|
||||
| show | Fills in deficits to have a more homogenous dose distribution. Shifts dose lines and brings Dmax closer to the skin surface when skin sparing is not desirable (Mosby’s RT Study Guide, pg. 102).
🗑
|
||||
| For non-isocentric treatments, _______ is the factor of choice to demonstrate central axis dose at a given depth. | show 🗑
|
||||
| When looking up the PDD or TMR for a given depth and field size, _______ should be used when there are blocks or MLC. | show 🗑
|
||||
| HDR isotopes deliver at a dose rate =_______cGy/min | show 🗑
|
||||
| show | 0.5 to 2.0 cGy/min. (Mosbyâs RT Study Guide, pg. 108).
🗑
|
||||
| show | The 50% isodose line in low energy beams like Cobalt 60 or the isodose line at a depth of 10 cm for higher energy beams used in modern linear accelerators (Mosby’s RT Study Guide, pg. 101).
🗑
|
||||
| What is the Dmax for a 1.25 MV beam? | show 🗑
|
||||
| show | 1.0 cm (RT Essentials, pg. 140).
🗑
|
||||
| What is the Dmax for a 6 MV beam? | show 🗑
|
||||
| show | 2.5 cm (RT Essentials, pg. 140).
🗑
|
||||
| show | 3.5 cm (RT Essentials, pg. 140).
🗑
|
||||
| show | 4.0 cm (RT Essentials, pg. 140).
🗑
|
||||
| show | Image fusion or image registration (W/L, pg. 542).
🗑
|
||||
| What is the practical range in tissue for a 10 MeV electron beam? | show 🗑
|
||||
| show | 200 cGy/5 = 40 cGy; AP field = 40 x 3 = 120 cGy; PA field = 40 x 2 = 80 cGy.
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Created by:
100001400829352
Popular Radiation Therapy sets