Virtual Source Distance Equation - ANSWER (R100/R110) =
((VSD+Dmax+gap)/(VSD+Dmax))^2
Dose Delivered at Time - ANSWER D(t) = D0(rate)/decay_constant*(1-e^(-dc(t))
D(t) = 1.44*D0(rate)*(1-e^(.693/T1/2*t))
TG-43 Geometry Function (Non-perpendicular) - ANSWER Gl = Beta/(L*r*sin(theta))
Beta = angle between two ends of source to point
theta = angle between r and x axis
L = length of source
TG- 43 Geometry Function (Perpendicular) - ANSWER Gl = 1/(r^2 - (L^2/4))
Beta from TG-43 - ANSWER cos(Beta) = A.B/(|A||B|)
Area of Ellipse - ANSWER Ae = πab
Secular Equilibrium - ANSWER Ap = Ad after 25 days
T1/2 of parent is 100-1000 times that of daughter
Transient Equilibrium - ANSWER • Transient equilibrium occurs when the half-life of the
parent (T1) is not much longer than that of the daughter (T2) (e.g., decay of 99Mo to
99mTc). At transient equilibrium, the daughter activity A2 and the parent activity A1 are
related by: A2 = A1 × T1/(T1 - T2).
No Equilibrium - ANSWER daughter half-life longer than parent half-life
- activity of parent & daughter approx equal to activity of daughter (after approx 7 half-
lives of daughter)
Specific Heat of Water - ANSWER 1 cal/(g*K) or 4.184 J/(g*K)
Minimum Detectable Activity - ANSWER MDA =
4.66*stdBkd+3/(Geometric_Eff*Intrinsic_Eff*timeBkd(s))
Also MDA = 3*SQRT(Rb/t) 99% conf interval
Standard Deviation of Net Count Rate - ANSWER StdNetCntRate =
SQRT((SQRT(Cnet)/tnet)^2+(SQRT(CBkd)/tBkd)^2)
Percent Error in Net Counts - ANSWER %Error = StdNetCntRate/Netcpm
,Person Sievert Equation - ANSWER P-Sv =
#PeopleD1*D1+#PeopleD2*D2+#PeopleD3*D3+...
Ev Per Ion Pair - ANSWER 33.97 eV/IP or 33.97 J/C
Joule per eV - ANSWER 1.6*10^(-19) J/eV
Roentgen - ANSWER 2.58 * 10 ^ (-4) C/Kg
Atoms to Grams conversion - ANSWER Grams = Atoms * Aw(g/mol)/NA(atoms/mol)
Rad - ANSWER 100 ergs/gram , 1cGy , absorbed dose
Joule Units - ANSWER 1 Nm = kg*m^2/s^2
Newton Units - ANSWER kg*m/s^2
Kinetic Energy of Ejected Electron - ANSWER KE = h*nu-bindingenergy
Compton Scattered Photon Equation - ANSWER E' = E0/(1+E0/0.511*(1-
cos(thetaphoton))
Electron Angle Compton Scatter - ANSWER Cos(Phielectron) = 1
+E0/.511*tan(thetaphoton/2)
Ultrasound Intensity - ANSWER dB = 10*log(I/I0)
attenuation linear with depth
HVL - ANSWER HVL = ln(2)/Mu(linear attn. coef)
TVL - ANSWER TVL = ln(10)/Mu(linear attn. coef)
Root Mean Square Voltage - ANSWER Vrms = Vpeak/Sqrt(2)
Force on Particle in B Field - ANSWER FM = qv x B = qvB if 90Deg
Power Reflected in Linac - ANSWER Alpha = (z2-z1)/(z2+z1)
Minimum reflected when alpha = 0
Speed of Electron (Fraction of C) - ANSWER Etotal = gamma*m0*c^2
Find Gamma
Gamma = 1/(Sqrt(1-B^2))
Solve for B
, Waveguide Power Equation - ANSWER P = V^2/(Z*L)
P = 5 mW
V = highest e- energy (20-22)
Z = Shunt Impedance (Mohms/m)
L = Accelerator Length (m) (1m)
Acoustic Impedance - ANSWER Z = Rho*C
Z = pascal * seconds/meter or rayl
Rho = density
c = speed in medium
Signal Transmitted through boundary - ANSWER T = 4*z1*z2/(z1+z2)^2
z1 & z2 acoustic impedance
Digestive Track Order (Start with Esophagus) - ANSWER Esophagus, Stomach,
Duodenum, Jejunum, Ileum, Cecum, Colon, Rectum
PDD Inherently Contains - ANSWER Inverse Square Correction & Attenuation
PDD to TMR Equation - ANSWER TMR =
PDD*(SSD+d)/(SSD+Dmax)^2*(Sp(Dmax)/Sp(d))
TG-137 Dose Recommendations - ANSWER Prostate = 145 Gy
Urethra = 10% not exceeding 150% of Rx
V100 > 95%
Rectum D2cc < Rx
SRS Dosimetry Chamber Diameter - ANSWER < 1mm
APBI Skin and Rib Dose Limit - ANSWER 425 cGy
TG-30 TSE Vertical and Horizontal Uniformity - ANSWER 8% and 4 %
CSI Symptoms - ANSWER Sore Throat/Mouth, Nausea, Dysphagia
What Disease is Treated with TBI, CSI, Non-Coplanar Isometric Beams - ANSWER
Leukemia, Medulloblastoma, Retinoblastoma
Uses for Sr-89, I-131, Y-90, P-32, Sm-153, Ra-223, Tc-99m - ANSWER Bone Mets,
Thyroid Cancer, Refractory Lymphoma/Liver, Excessive RBC, Bone Mets, Diagnostic
Imaging
((VSD+Dmax+gap)/(VSD+Dmax))^2
Dose Delivered at Time - ANSWER D(t) = D0(rate)/decay_constant*(1-e^(-dc(t))
D(t) = 1.44*D0(rate)*(1-e^(.693/T1/2*t))
TG-43 Geometry Function (Non-perpendicular) - ANSWER Gl = Beta/(L*r*sin(theta))
Beta = angle between two ends of source to point
theta = angle between r and x axis
L = length of source
TG- 43 Geometry Function (Perpendicular) - ANSWER Gl = 1/(r^2 - (L^2/4))
Beta from TG-43 - ANSWER cos(Beta) = A.B/(|A||B|)
Area of Ellipse - ANSWER Ae = πab
Secular Equilibrium - ANSWER Ap = Ad after 25 days
T1/2 of parent is 100-1000 times that of daughter
Transient Equilibrium - ANSWER • Transient equilibrium occurs when the half-life of the
parent (T1) is not much longer than that of the daughter (T2) (e.g., decay of 99Mo to
99mTc). At transient equilibrium, the daughter activity A2 and the parent activity A1 are
related by: A2 = A1 × T1/(T1 - T2).
No Equilibrium - ANSWER daughter half-life longer than parent half-life
- activity of parent & daughter approx equal to activity of daughter (after approx 7 half-
lives of daughter)
Specific Heat of Water - ANSWER 1 cal/(g*K) or 4.184 J/(g*K)
Minimum Detectable Activity - ANSWER MDA =
4.66*stdBkd+3/(Geometric_Eff*Intrinsic_Eff*timeBkd(s))
Also MDA = 3*SQRT(Rb/t) 99% conf interval
Standard Deviation of Net Count Rate - ANSWER StdNetCntRate =
SQRT((SQRT(Cnet)/tnet)^2+(SQRT(CBkd)/tBkd)^2)
Percent Error in Net Counts - ANSWER %Error = StdNetCntRate/Netcpm
,Person Sievert Equation - ANSWER P-Sv =
#PeopleD1*D1+#PeopleD2*D2+#PeopleD3*D3+...
Ev Per Ion Pair - ANSWER 33.97 eV/IP or 33.97 J/C
Joule per eV - ANSWER 1.6*10^(-19) J/eV
Roentgen - ANSWER 2.58 * 10 ^ (-4) C/Kg
Atoms to Grams conversion - ANSWER Grams = Atoms * Aw(g/mol)/NA(atoms/mol)
Rad - ANSWER 100 ergs/gram , 1cGy , absorbed dose
Joule Units - ANSWER 1 Nm = kg*m^2/s^2
Newton Units - ANSWER kg*m/s^2
Kinetic Energy of Ejected Electron - ANSWER KE = h*nu-bindingenergy
Compton Scattered Photon Equation - ANSWER E' = E0/(1+E0/0.511*(1-
cos(thetaphoton))
Electron Angle Compton Scatter - ANSWER Cos(Phielectron) = 1
+E0/.511*tan(thetaphoton/2)
Ultrasound Intensity - ANSWER dB = 10*log(I/I0)
attenuation linear with depth
HVL - ANSWER HVL = ln(2)/Mu(linear attn. coef)
TVL - ANSWER TVL = ln(10)/Mu(linear attn. coef)
Root Mean Square Voltage - ANSWER Vrms = Vpeak/Sqrt(2)
Force on Particle in B Field - ANSWER FM = qv x B = qvB if 90Deg
Power Reflected in Linac - ANSWER Alpha = (z2-z1)/(z2+z1)
Minimum reflected when alpha = 0
Speed of Electron (Fraction of C) - ANSWER Etotal = gamma*m0*c^2
Find Gamma
Gamma = 1/(Sqrt(1-B^2))
Solve for B
, Waveguide Power Equation - ANSWER P = V^2/(Z*L)
P = 5 mW
V = highest e- energy (20-22)
Z = Shunt Impedance (Mohms/m)
L = Accelerator Length (m) (1m)
Acoustic Impedance - ANSWER Z = Rho*C
Z = pascal * seconds/meter or rayl
Rho = density
c = speed in medium
Signal Transmitted through boundary - ANSWER T = 4*z1*z2/(z1+z2)^2
z1 & z2 acoustic impedance
Digestive Track Order (Start with Esophagus) - ANSWER Esophagus, Stomach,
Duodenum, Jejunum, Ileum, Cecum, Colon, Rectum
PDD Inherently Contains - ANSWER Inverse Square Correction & Attenuation
PDD to TMR Equation - ANSWER TMR =
PDD*(SSD+d)/(SSD+Dmax)^2*(Sp(Dmax)/Sp(d))
TG-137 Dose Recommendations - ANSWER Prostate = 145 Gy
Urethra = 10% not exceeding 150% of Rx
V100 > 95%
Rectum D2cc < Rx
SRS Dosimetry Chamber Diameter - ANSWER < 1mm
APBI Skin and Rib Dose Limit - ANSWER 425 cGy
TG-30 TSE Vertical and Horizontal Uniformity - ANSWER 8% and 4 %
CSI Symptoms - ANSWER Sore Throat/Mouth, Nausea, Dysphagia
What Disease is Treated with TBI, CSI, Non-Coplanar Isometric Beams - ANSWER
Leukemia, Medulloblastoma, Retinoblastoma
Uses for Sr-89, I-131, Y-90, P-32, Sm-153, Ra-223, Tc-99m - ANSWER Bone Mets,
Thyroid Cancer, Refractory Lymphoma/Liver, Excessive RBC, Bone Mets, Diagnostic
Imaging
