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48 Cards in this Set
- Front
- Back
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Dose rate for HDR
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up to 400 cGy/min
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Doser rate for LDR
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40 - 200 cGy/hr
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Cs 137 uses
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tandem and oviods, LDR
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Definition: point A for gyno implants
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2 cm cephalad external cervical os, 2 cm lat uterine tandem
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Defintion: point B
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Used in Manchester system for intracavitary implants, 3 cm pt A and represents level obdurator nodes
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Definition: basal dose
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85% of the minimal doses between all sources, used in Paris system
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Why does does dist for brachy follow ISF?
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Attenuation and scanner dose build up cancel out
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When is ISF not accurate for iso?
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low energy sources
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energy Gold 198
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410 keV
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energy Pd 103, half life
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21 keV, 17 days
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Iodine 125: use
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perm seeds
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Ir 192: use
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LDR HDR
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What source used for tandem and ovoids?
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Cs 137
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Define total source strength
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Kerma in air at 1-meter
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Isotope for nasopharyngeal implants
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Cs 137
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Source used for HDR
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Ir 192
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Three sources used for permanent implants
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I-125, Pd-103, Gold-198
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LDR sources
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Cs 137, Ir 192
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Radioactive sources in tandems and ovoids are in this form
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tubes
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Isotope energy 29 keV
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I-125
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Isotope energy 370 keV
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Ir 192
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Isotope energy 410 keV
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Gold 198
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Ref pts for intracavity brachy by ICRU
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bladder and rectal wall, lymph trapezoid, pelvic wall pts
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System of implants defines stated dose as max dose?
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Quimby
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System of implants defined states dose as min?
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Manchester or PP
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Which system of implants does NOT use crossing needles?
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Paris, source length 40% greater target volume
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Spacing of implants varies with target
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PP
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Even spacing implants 1 cm apart
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Quimby
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Variable but equal spacing implants
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Paris
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Constant linear activity, implant system?
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Paris or Quimby
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No restrictions to pt at this dose rate
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0.1 mRm/hr
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limit contact w children at this dose rate
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> than 0.2 mRm/hr
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Single channel Bougie applicator
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esophagus
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Single channel candle applicator
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vaginal
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vaginal applicators
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single channel candle, tandem and ovoids
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multichannel needle template
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prostate, rectum
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multiplane needle template
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breast
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applicator skin
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single-plane multi channel applicator
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relationship between half life and tx time
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shorter half life, shorter tx time
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relationship initial dose rate and half life
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shorter half life, larger initial rate
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relationship tx time and initial activity
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higher activity means shorter tx time
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# dps in 1 Ci
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3.7 10^10
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SI unit activity
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Bq
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Which rad transport label does NOT require T1?
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White 1
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Yellow 1 indicates?
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50 mrem or LESS at surface
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If T1 exceeds 1 mrem at 1 m
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Yellow 2
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Occupational dose limit to hands
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500 mSv or 50 rem
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max annual exposure whole body for training
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1 mSv
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