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334 Cards in this Set
- Front
- Back
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Procedure Most Likely to Employ Negative Shielding
|
Nasopharynx Treatment
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Oblique Field Used to Treat Patients Who Have Had a Right Pneumonectomy
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Right
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Factor Dmax is Most Dependant On
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Physical Tissue Density
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Complication That May Occur at Doses of 2000 cGy or More to the Stomach or Small Intestine
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Intestinal Hemorrhage
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Treatment Depth for 13 MeV Beam
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3-4 cm
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Time Patient is Most at Risk of Experiencing Radiation Nephropathy
|
A Few Weeks After Treatment Finishes
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Type of Treatment For Which Dose Must Be Verified By an Ion Chamber
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MV
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Most Commonly Diagnosed Head and Neck Cancer
|
Oral Cavity
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Types of Cervical Cancer Considered Stage I
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Pre-invasive
Carcinoma in Situ Intra-epithelium |
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Factor Which Increases the Likelihood of a Photoelectric Interaction Occuring
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Higher Atomic Number
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Upper Limit for KeV to Result in Photoelectric Interactions
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60 KeV
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Tolerance for Split Field Test for Parallel Opposed Fields
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Greater Than 2.2 mm Gap
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Tolerance Dose for Cataract Development
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500 cGy
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Condition Which Occurs as the Result of Renal Disease
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Proteinuria
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Tolerance Dose for Blindness as the Result of Irradiation of the Optic Nerve or Chiasm
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5500 cGy
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Complication Most Likely to Result From Exposure to 1.4 Sv (140 rem) Over a Year
|
Leukemia
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Examples of Deterministic Effects of Radiation
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Cataract, Infertility, Erythema
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Examples of Stochastic Effects of Radiation
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Secondary Malignancy, Genetic Aberrations
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Type of Effect for Which There Is a Threshold Dose
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Deterministic Effects
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Type of Effect for Which There Is No Safe Threshold Dose
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Stochastic Effects
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Factor Dependant on Dose for Deterministic Effects
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Severity of Reaction
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Factor Dependant on Dose for Stochastic Effects
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Probability of Reaction Occuring
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Tolerance Dose for Parotid
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3200 cGy to 2/3 of the Parotid
|
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Tolerance Dose for Heart
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1/3 - 6000 cGy
2/3 - 4500 cGy 3/3 - 4000 cGy |
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Tolerance Dose for Brainstem
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1/3 - 6000 cGy
2/3 - 5300 cGy 3/3 - 5000 cGy |
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Tolerance Dose for Esophagus
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1/3 - 6000 cGy
2/3 - 5800 cGy 3/3 - 5500 cGy |
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Tolerance Dose for Rectum
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6000 cGy
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Tolerance Dose for Lung
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1/3 - 4500 cGy
2/3 - 3000 cGy 3/3 - 1750 cGy |
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Tolerance Dose for Kidney
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1/3 - 5000 cGy
2/3 - 3000 cGy 3/3 - 2300 cGy |
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Tolerance Dose for Liver
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1/3 - 5000 cGy
2/3 - 3500 cGy 3/3 - 3000 cGy |
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Tolerance Dose for Spinal Cord
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5-10 cm - 5000 cGy
20 cm - 4700 cGy |
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Types of White Blood Cells
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Monocytes, Neutrophils, Eosinophils
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Side Effect That Can Result in a Treatment Break For Patients Undergoing Pelvic Treatment
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Acute Enteritis
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Most Commonly Diagnosed Malignancy in Pregnant Women
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Lymphomas
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Normal Red Blood Cell Values in Adult Males
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5,000,000 / cc
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Amount of Radiation a Patient Is Required to Have a Private Room and Bath If They Exceed
|
30 mCi Administered
5 mRem / hr 1 m From Their Skin Surface |
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Tool Used to Measure Jaw Symmetry
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Machinist's Dial Indicator
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Dose Equivalent Limit for Infrequent Exposures to the Public
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5 mSv
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Effect Of Increased Field Size On Exposure Rate
|
Increased Exposure Rate
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Type of Treatment Machine Requiring 2 Independent Dose Monitors
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Linear Accelerator
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Phases of Grieving
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Shock
Denial Bargaining Guilt Anger Depression Acceptance |
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Functions of a Hickman Catheter
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Chemotherapy Administration
Dialysis Blood Draws Apheresis Parenteral Nutrition |
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Cause of Petechiae
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Chemotherapy Leading to Blood Clotting Disorders
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Dose Equivalent Limit for Entire Gestation of Health Care Worker
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0.5 mSv
|
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Clonal Expansion
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Many Cells Produced From a Single Cell
Mechanism That Transforms Cell Populations Into Neoplasms |
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Effect of Shock on Blood Pressure
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Patient is Hypotensive
|
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Exposure Limit for Controlled Areas
|
1 mSv / week
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Mechanism That Bends the Electron Stream Onto the Target
|
Beam Transport System
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Five Rs of Radiobiology
|
Radiosensitivity
Repair Reoxygenation Redistribution Repopulation |
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Therapeutic Ratio Equation
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NTTD / TLD
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Frequency of Testing X-Ray Output Consistency
|
Daily
|
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Stage I Hodgkin's Disease
|
Disease Within a Single Lymph Node Region or a Single Extralymphatic Site without Lymph Node Involvement
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Stage II Hodgkin's Disease
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Disease Within More Than 1 Lymph Node Region on the Same Side of the Diaphragm or Disease Within an Extralymphatic Site With Lymphatic Involvement, With Entire Scope of Disease Limited to One Side of the Diaphragm
|
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Stage III Hodgkin's Disease
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Disease Exists On Both Sides of the Diaphragm
May Include Extralymphatic Extension or Involvement of the Spleen |
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Stage IV Hodgkin's Disease
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Diffuse Involvement of 1 or More Extralymphatic Organs or Extralymphatic Disease and Distant Metastatic Spread
|
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Diseases Treated With Whole Abdomen Fields
|
Ovarian Cancer
Bulky Seminomas Wilm's Tumors |
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Abdominal Disease Not Treated Using Whole Abdomen Fields
|
Nephroblastomas
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Most Common Form of Esophageal Cancer and Percentage of Diagnoses This Accounts For
|
Squamous Cell Carcinoma
90% |
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Type of Esophageal Cancer Associated with Barrett's Esophagus
|
Adenocarcinoma
|
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Complication That May Occur as the Result of Exposures of 1500 cGy or More to the Prepubescent Breast
|
Stunted Breast Development
|
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Uremia
|
Presence of Poisonous Blood Products in the Patient's Blood As the Result Of Kidney Failure
|
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Location of the Pancreatic Head
|
In the C Loop of the Duodenum
|
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Most Serious Consequence of Whole Body Irradiation
|
Hematopoietic Suppression
|
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End Points for Tolerance of the Rectum
|
Proctitis
Necrosis Fistula Stenosis |
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End Point for Tolerance of the Heart
|
Pericarditis
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End Points for Tolerance of the Esophagus
|
Clinical Stricture
Perforation |
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End Point for Tolerance of the Lung
|
Pneumonitis
|
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End Points for Tolerance of the Spinal Cord
|
Myelitis
Necrosis |
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End Points for Tolerance of the Brainstem
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Necrosis
Infarction |
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End Point for Tolerance of the Liver
|
Liver Failure
|
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End Point for Tolerance of the Kidney
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Clinical Nephritis
|
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Type of Cancer Examined Using Lymphangiogram
|
Testicular Cancers
|
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Most Common Region of Bulge Within the Electron Isodose Lines
|
20 - 40 %
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Depth of 50% Depth Dose at Central Axis for a 10 x 10 Field on a CO-60 Machine
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12 cm
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Rationale for Treating Obese Female Patients Undergoing Pelvic Irradiation in the Prone Position
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Decreased Dose to the Patient's Bladder
|
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Most Common Cause of Light Field Incongruence In a High Energy Linear Accelerator
|
Misaligned Collimator Mirror
|
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Ideal Parameters for Phantoms
|
Same Electron Density
Same Atomic Number Same Mass Density |
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Method of Maintaining Skin Sparing On a Sloped Skin Surface
|
Compensating Wedges
|
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Equation for Determining Dose for High Energy Electron Beams
|
MU = Prescribed Dose / (cGy / MU)(Area Factor)(% Depth Dose)
|
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Factors That Must Be Included When Labeling Wedges
|
Wedge Angle
Name of Treatment Unit Maximum Field Size |
|
|
Symptom Treated Using Decongestants for Patients Undergoing Nasopharyngeal Treatment
|
Serous Otitis Media
|
|
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Hinge Angle Equation
|
Wedge Angle = (180 - Hinge Angle) / 2
|
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Hinge Angle
|
Angle Separating the Two Central Axes
|
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Rationale for Using Wedges to Treat Laryngeal Cancers
|
Used to Modify Isodose Distribution, and Not to Decrease the Number of Hot Spots
|
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Legal Violation for Intentionally Failing to Cover a Patient
|
Invasion of Privacy
|
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Block Used for the Longest Source to Surface Distance
|
Straight Block
|
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Best Way to Avoid Being Charged With Assault
|
Explanation of All Actions to the Patient
|
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First Sign of Bacterial Infection
|
Temporary Increase in the Number of Leukocytes
|
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Hysterometer
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Graduated Sound for Measuring the Depth of the Uterine Cavity
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Colpostat
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Medical Instrument Designed to Facilitate Vaginal Treatment
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Method Used to Treat Tumors On Large, Curved Surfaces, Such As Superficial Chest Wall Disease
|
Electron Arc
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Type of Cancer Most Likely to Result in Superior Vena Cava Syndrome
|
Metastatic Disease to the Brain or Spinal Cord
|
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Appearance of Mucosa Immediately Following the Completion of Treatment for Laryngeal Cancer
|
Irregular Mucosal Slough
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Side Effect That Occurs As the Result of Intracellular Edema
|
Moist Desquammation
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Condition Minimized Using the Application of Cornstarch
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Radiation Induced Skin Reaction
|
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Anemia
|
Decrease in the Number of Circulating Red Blood Cells
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Highest Dose to Which Structure Using High Energy Photons to Treat With a Bone Interface
|
Soft Tissue Surrounded By Bone
|
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Virtual Source
|
Point From Which An Electron Beam Appears to Diverge
|
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Primary Lymphatic Drainage of the Paranasal Sinuses and Nasal Pharynx
|
Retropharyngeal Lymph Nodes
|
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Advantage of Cerrobend in Block Construction Versus Lead
|
Lower Temperature Required to Shape
|
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Factors Linear Attenuation Coefficient Is Dependant On
|
Beam Energy
Physical Density of Attenuating Material Atomic Number of Attenuating Material |
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Tolerance Dose of Whole Brain Treatment
|
6000 cGy
|
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Impact of Treating Less Cross-Sectional Area
|
Decreased Exposure Rate On the Patient's Skin Surface
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Limit for Radioactivity Surrounding a Patient Who Is Emitting Radiation's Room
|
5 mRem / hr
|
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Carcinoma
|
Malignant Cancer Arising From Epithelial Cells
|
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Structures Shielded Treating Mantle Fields
|
Lungs
Humeral Heads Larynx Spinal Cord Heart |
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Lymph Node Regions Included in Mantle Fields
|
All Major Regions Above the Diaphragm
Submandibular Occipital Cervical Supraclavicular Infraclavicular Axillary Hilar Mediastinal |
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|
Superior Border of Mantle Field
|
Inferior Border of Mandible Anteriorly
To Include Occipital Nodes Posteriorly |
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Inferior Border of Mantle Field
|
Level of the Insertion of the Diaphragm
About T10 |
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Lateral Borders of the Mantle Field
|
To Include the Axillary Lymph Nodes
|
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Patient Position for Treating Mantle Fields
|
Supine
Arms Akimbo Chin Fully Extended |
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Rationale for Chin Extension Treating Mantle Fields
|
Spares Oral Mucosa, Particularly Posterior Field Exit Dose
|
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Tolerance Dose of Pituitary
|
4500 - 5500 cGy
|
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Dose Equivalent Limit for Annual Occupational Exposure
|
50 mSv (5 rem) for Stochastic Effects
|
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Annual Dose Equivalent Limit for Lens of the Eye
|
150 mSv (15 rem)
|
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Dose Equivalent Limit for Annual Occupational Exposure for Deterministic Effects on Whole Body
|
500 mSv (50 rem)
|
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Dose Equivalent Limit for Cumulative Radiation Exposure
|
10 mSv (1 rem) x Age In Years
|
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Annual Dose Equivalent Limit for Continuous or Frequent Public Exposure
|
1 mSv (0.1 rem)
|
|
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Dose Equivalent Limit for Exposure to an Embryo or Fetus
|
0.5 mSv (0.05 rem) / month
5 mSv (0.5 rem) Over Course of Gestation |
|
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Annual Negligible Individual Risk Level Dose Equivalent
|
0.01 mSv (0.001 rem)
|
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|
Sarcoma
|
Cancer Arising From Mesenchymal Tissue, Including Connective, Supportive, or Soft Tissue
|
|
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Exostotic
|
Growing Outward From Anatomical Structures
|
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Primary Lymphatic Drainage of the Colon
|
Internal and Presacral Mesenteric Lymph Nodes
|
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Structures Destroyed As a Consequence of Large Lymphoid Irradiation
|
Lymphoblasts
Lymphocytes Megakaryocytes |
|
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Treatment Used for Generalized Abdominal Disease
|
Whole Abdomen Irradiation with Boost
|
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Beam Energy Above Which Backscatter at Depth Dose Becomes Negligible
|
8 MV
|
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Diagnostic Test Used for Bladder Carcinomas
|
Fulguration
|
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Factors Which Impact the Effect of Homogeneities
|
Size of Inhomogeneity
Type of Radiation Delivered Energy of Radiation Delivered |
|
|
Maximum Energy of a Scattering Object at a 180 degree Angle
|
511 KeV
|
|
|
Treatment Options for Early Stage I Wilm's Tumors
|
Vincristine
Postoperative Radiation Therapy Actinomycin |
|
|
Substances Used to Deliver Immunotherapy
|
Monoclonal Antibodies
|
|
|
Common Characteristics of Neoplastic Processes
|
Self-propagation
Autonomy Anaplasia |
|
|
Symptoms of Radiation Induced Acute Hepatitis
|
Acites
Hepatomegaly Portal Vein Hypertension |
|
|
Use of Scatter - Air Ratio
|
Determination of Amount of Scatter Produced by Irregular Fields
|
|
|
Factors Which Influence the Shape of Isodose Curves
|
SAD
SSD Wedge Angle |
|
|
Cold Spot Resulting From Treatments Using Proimos Head Treatment Device
|
Behind Acanthion
|
|
|
Primary Goal of Radiation Simulation
|
Assurance That Treatment Fields Enchompass the Target Value
|
|
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Normal Adult Blood Pressure
|
120 / 80 mmHg
|
|
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Hormonal Conditions Associated With Increased Bone Turnover
|
Increased Parathyroid Hormone
Increased Adrenal Cortical Hormone Decreased Calcitonin |
|
|
Malignant Transformation
|
Process By Which Normal Cells Acquire the Properties of Cancer
|
|
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Substances That Synthesize Antimicrobial Proteins Which Attach to the Bacterial Surface
|
Complement
Interferon |
|
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Treatment Most Likely to Result in Decreased Number of White Blood Cells
|
Skeletal Disease
|
|
|
Organ for Which Radiation Treatment is Most Likely to Result in Immunosuppression and Decreased Blood Counts
|
Spleen
|
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|
Percentage of Radiation Dose Absorbed in the First 2 cm of an Orthovoltage Beam
|
10%
|
|
|
Region Esophageal Adenocarcinomas Are Most Likely to Develop
|
Lower Thoracic Esophagus
|
|
|
Region of Internal Mammary Lymph Nodes
|
Lateral Border of the Sternum
|
|
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Consequence of Diminished Pituitary Function
|
Decreased Sex Hormone Production
Decreased Cortisone Production Decreased Thyroxin Production |
|
|
Early Response to Irradiation of the Lung
|
Radiation Pneumonitis
|
|
|
Most Common Cause of Mechanical Bladder Obstruction
|
Enlarged Prostate Gland
|
|
|
Factors Influencing Prescribed Dose
|
Cytogenetic Factors
Diagnostic Stage Pathologic Grade |
|
|
Potential Complication of Apical Lung Treatments
|
Extremity Defects Secondary to Brachial Plexus Injuries
|
|
|
Systems That Originate As the Endoderm
|
Gastrointestinal System
Genitourinary System Respiratory System |
|
|
Structures That Are Most Likely to Experience Chemical Changes Resulting in Radiation Induced Cell Death
|
Cell Membranes
Lysosomes |
|
|
Tolerance Dose for the Brachial Plexus
|
5500 cGy
|
|
|
Percentage of Patients Who Develop Liver Metastases
|
50%
|
|
|
Mechanism of Liver Metastases
|
Filtration of Hematogenous Tumor Cells
|
|
|
Primary Lymphatic Drainage from the Testis
|
Para-Aortic Lymph Nodes
|
|
|
Organs at Risk During Intracavitary Cervical Brachytherapy
|
Bladder
Rectum |
|
|
Purpose of Shielding
|
Avoid Unneccessary Exposure to Surrounding Tissues
Not To Protect All Critical Organs |
|
|
Mechanism of Flattening Filter for Treatment Using a 4 MV Beam
|
Decreased Dose Away From the Central Axis
|
|
|
Lymphatics Usually Included In Breast Treatment
|
Axillary
Internal Mammary Supraclavicular |
|
|
Situation Requiring the Employment of TAR
|
Variable SSD
|
|
|
Presence of Disease Within the Patient's Cervical Lymph Nodes Demands Inclusion of Which Structure Within the Treatment Volume
|
Tonsils
|
|
|
Most Common Mechanism of Spreading Infection Within the Hospital
|
Direct Contact
|
|
|
Clinical Management of Small Bowel Symptoms
|
Avoid Excessive Fiber Consumption
Avoid Lactose Avoid a High Fat Diet |
|
|
Exposure Accuracy for the Dose Delivery System
|
Within 5% of the Delivered Dose
|
|
|
Autonomy
|
Disregard for Normal Limitations of Growth Exhibited By Cancer Cells
|
|
|
Equivalent Dose Limit for Occupational Exposure to the Lens of the Eye for Deterministic Effects
|
150 mSv (15 rem)
|
|
|
Complication Suggested By Dry Cough and Shortness of Breath When Treating Thymomas
|
Radiation Pneumonitis
|
|
|
Hyperplastic
|
Abnormal Increase in Cells of a Tissue or Organ With Subsequent Enlargement or Increased Response to Stimulus
|
|
|
Factors Most Likely to Interfere With Accuracy of Pap Tests
|
Douches
Vaginal Infections |
|
|
Parameters for Imaging Port Films
|
Single Emulsion Film
Lead Cassettes |
|
|
Skin Care Recommendations
|
Use Mild Soap Only
Continue Using Appropriate Topical Steroid Creams |
|
|
Contraindication for Continuing Hodgkin's Disease Treatment
|
White Blood Cell Count Under 2000
|
|
|
Normal White Blood Count Values
|
4300 - 10800
|
|
|
Stage I Cervical Cancer
|
Cervical Cancer Confined to the Uterus
|
|
|
Stage II Cervical Cancer
|
Cervical Cancer Invading Beyond the Wall of the Uterus But Not To The Pelvic Sidewalls or Lower 1/3 of the Vagina
|
|
|
Stage III Cervical Cancer
|
Tumors That Extend To the Pelvic Sidewall or Lower 1/3 of the Vagina
Tumors That Cause Hydronephrosis or a Nonfunctioning Kidney |
|
|
Stage IVA Cervical Cancer
|
Tumors Tha tInvade the Mucosa of the Bladder or Rectum
Tumors That Extend Beyond the True Pelvis |
|
|
Difference Between Tissue Air Ratio and Percent Depth Dose
|
Percent Depth Dose is Dependant on the SSD and Tissue Air Ratio Is Not
|
|
|
Structures That Are Always Included in Nasopharynx Fields
|
Posterior 1/3 of the Orbits
Retropharyngeal Lymph Nodes |
|
|
Structure Which May or May Not Be Included in Nasopharynx Fields
|
Base of Skull
|
|
|
More Radiosensitive Muscle
|
Pterygoid Muscle
|
|
|
Factor With Greatest Influence of Delivery of Dose at Depth Treating Using MV
|
Beam Quality
|
|
|
Factors Geometric Divergence is Dependant Upon
|
Field Diameter
Treatment Angle |
|
|
Most Common Location For Vaginal Cancers
|
Posterior Upper 1/3 of the Vagina
|
|
|
Most Common Pediatric Malignancy
|
Acute Lymphocytic Leukemia
|
|
|
Form of Acute Leukemia Diagnosed Most Often in Adults
|
Acute Myelogenous Leukemia
|
|
|
Peak Age of Incidence for Chronic Lymphocytic Leukemia
|
71 years
Rarely Diagnosed in Patients Under the Age of 40 |
|
|
Peak Age of Incidence for Chronic Myelogenous Leukemia
|
Mid 40s
Rarely Diagnosed in Patients Under the Age of 20 |
|
|
Medium Used to Calibrate Electron Beams
|
Distilled Water
|
|
|
Lymph Nodes Included in Treament Fields for Prostate Cancer Treatment
|
Obturator Lymph Nodes
Common Iliac Lymph Nodes |
|
|
Purpose of Cerebral Spinal Fluid in Ventricles of the Brain
|
Mechanical and Immunological Protection of the Brain
|
|
|
Xanthosis
|
Yellowing of the Skin Without Yellowing of the Eyes
|
|
|
Organ at Greatest Risk for Complication Using 4500 cGy to Treat the Whole Abdomen
|
Kidney
|
|
|
Conversion Factor For Sv and Gy
|
1 Sv = 1 Gy
|
|
|
Conversion Factor for Rad and Gy
|
1 Gy = 100 rad
|
|
|
Conversion Factor for Curies and Bq
|
1 Ci = 3.7 x 10E10
|
|
|
Conversion Factor for Rem and Sv
|
1 Sv = 100 rem
|
|
|
Conversion Factor for Gy and J/kg
|
1 Gy = 1 J/kg
|
|
|
Autoradiography
|
Used to Evaluate the Distribution, Uniformity, and Symmetry of Brachytherapy Sources
|
|
|
Type of Cancer Diagnosed Most Often in the Vagina
|
Squamous Cell Carcinoma
|
|
|
Characteristics of Nodular Sclerosing Hodgkin's Disease
|
Many Reed Sternberg Cells
Lacunar Spaces |
|
|
Liver Secretions Active in Blood Coagulation
|
Prothrombin
Fibrinogen |
|
|
Most Common Complication Associated with Eustachian Tube Inflammation Following Radiation Treatment
|
Serous Otitis Media
|
|
|
Target Volume
|
Area of Known and Presumed Tumor
|
|
|
Treatment Volume
|
Target Volume and Margin for Limitations of Setup Technique
|
|
|
Most Common Sites of Skin Cancers
|
Head
Neck Face Arms Hands |
|
|
Most Common Sites of Melanomas
|
Women's Legs
Men's Trunks and Faces |
|
|
Relative Biologic Effectiveness Equation
|
Dose From 250 keV x-ray / Dose From Test Radiation Needed to Produce the Same Biologic Effect
|
|
|
Klystron
|
Converts Kinetic Energy to Microwave Energy in Linear Accelerators Using Microwave Cavities Tuned Near Operating Frequency of the X-ray Tube
|
|
|
Linear Energy Transfer
|
Average Energy Deposited Per Unit Length To a Medium By Ionizing Radiation As It Passes Through the Medium
|
|
|
Relationship Between LET and RBE
|
Directly Proportional
|
|
|
Protraction Rate
|
Total Extent of Time Over Which The Dose Is To Be Delivered
|
|
|
Oxygen Enhancement Ratio
|
Comparison of Response of Cells to Radiation in the Presence and Absence of Oxygen
|
|
|
Oxygen Enhancement Ratio Equation
|
Radiation Dose Under Hypoxic or Anoxic Conditions / Radiation Dose Under Oxic Conditions to Produce the Same Effect
|
|
|
Relationship Between Oxygen Enhancement Ratio and Relative Biologic Effectiveness
|
Not As Straightforward, But Directly Proportional Under Ideally Oxygenated Conditions
|
|
|
Dose Resulting in Hematopoietic Syndrome
|
100 - 1000 cGy
|
|
|
Dose Resulting in Gastrointestinal Syndrome
|
1000 - 10000 cGy
|
|
|
Dose Resulting in Cerebrovascular Syndrome
|
5000 - 10000 cGy
|
|
|
Survival for Persons With Hematopoietic Syndrome
|
3 weeks - 2 months
|
|
|
Survival for Persons With Gastrointestinal Syndrome
|
3 - 10 days
|
|
|
Survival for Persons With Cerebrovascular Syndrome
|
Less Than 3 days
|
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Stages of Radiation Syndromes
|
Prodromal Stage
Latent Stage Manifest Illness Death |
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Symptoms of Prodromal Stage of Hematopoietic Syndrome
|
Nausea
Vomiting |
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Symptoms of Prodromal Stage of Gastrointestinal Syndrome
|
Nausea
Vomiting Diarrhea Cramping |
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Symptoms of Prodromal Stage of Cerebrovascular Syndrome
|
Nervousness
Confusion Nausea Vomiting Loss of Consciousness Burning Sensation of the Skin |
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Duration of Stages of Hematopoietic Syndrome
|
Prodromal Stage - Hours After Exposure
Latent Stage - Few Days to 3 Weeks Manifest Illness - 3 - 5 Weeks After Exposure Death - Within 2 - 6 Weeks, If Fatal, Dose Dependant |
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Symptoms of Manifest Illness of Hematopoietic Syndrome
|
Pancytopenia
Anemia Hemorrhage Serious Infection |
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Duration of Stages of Gastrointestinal Syndrome
|
Prodromal Stage - Within Hours of Exposure
Latent Stage - 2 - 5 Days After Exposure Manifest Illness - 5 - 10 Days After Exposure Death - During Second Week After Exposure |
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Symptoms of Manifest Illness for Gastrointestinal Syndrome
|
Nausea
Vomiting Diarrhea Fever |
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Biologic Mechanism Responsible for Gastrointestinal Syndrome
|
Depopulation of Crypt Cells, and Subsequent Denudation of the Villi
Decreased Absorption Leakage of Fluid Into the Lumen Dehydration Bacteria Can Access Circulating Blood, Leading to Overwhelming Infection Bone Marrow Demonstrates Severely Decreased Amount of Circulating Leukocytes Electrolyte Imbalance |
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Amount of Time to Recover From Hematopoietic Syndrome
|
3 weeks - 6 months, Dependant on Dose
|
|
|
Duration of Stages for Cerebrovascular Syndrome
|
Prodromal Stage - Minutes - Several Hours Following Exposure
Latent Stage - Several Hours or Less if Detectable Manifest Illness Stage - 5 - 6 Hours After Exposure Death - Less Than 3 Days |
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Symptoms of Manifest Illness for Cerebrovascular Syndome
|
Watery Diarrhea
Convulsions Coma |
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Possible Biologic Mechanisms for Cerebrovascular Syndrome
|
Extensive Blood Vessel Damage, Leading to Vasculitis, Meningitis, Edema, and Intracranial Pressure
|
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Indirect Hit Effect
|
Radiolysis of Water Ultimately Responsible for Transferring Energy from Ionizing Radiation From Irradiated Molecules to Non-Irradiated Molecules
|
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Direct Hit Effect
|
Radiation Damage to the DNA of the Irradiated Cells
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Key Molecule Transfer
|
Transfer of a Free Radical to a Key Molecule That May Result in Bond Breakage or Inactivation of Key Functions
|
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Magnetron
|
Vacuum Tube That Generates Microwaves
|
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Waveguide
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Hollow Tubelike Structure Directing the Microwave Power
|
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Most Significant Component of Beam Transport System
|
Bending Magnet
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Indications For Completing Treatment If the Door Lock is Inoperable
|
If Patient Setup Has Been Completed
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Device Used to Measure Dose Rate Consistency
|
Ion Chamber
|
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Annual Equivalent Dose for Occupational Exposure of Persons Under 18 years of Age
|
5 mSv (500 mRem)
|
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Acceptance Criteria for Field Flatness Over the Central 80% of the Field Using Photons
|
2%
|
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Acceptance Criteria for Radiation / Light Field Coincidence
|
2 mm or 1% On Side
|
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Interphase Death
|
Irradiation of the inCell During the G1, S, or G2 Phase That Results In Cell Death, Prior to Their Undergoing Mitosis
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Mitotic Delay
|
Cells In Interphase When They Are Irradiated Which Are Delayed In the G2 Phase
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Consequence of Mitotic Delay
|
Decreased M1 Phase Population, Resulting in Fewer Daughter Cells Produced
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Effect Of Radiation Dose On Mitotic Delay
|
Higher Dose Results In Longer Mitotic Delay
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Cellular Mechanism Involved In Mitotic Delay
|
Cells Attempts To Repair Injury Prior to Mitosis By Confirming DNA and Proteins Are Intact, To Avoid Disruptions in Cell Division or Cell Death
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Reproductive Failure
|
Decrease in Reproductive Integrity or Limits To Number of Potential Divisions Following Irradiation
|
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Type of Radiation Most Often Measured With Free-Air Ionization Chambers
|
X-Rays and Gamma Rays Up To 3 MeV
|
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Consequences of Misaligned Photon Beam
|
Displaced Focal Spot
Asymmetric Collimator Jaws Improper Rotational Axis of Collimator |
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Energy At Which Coherent or Thomson Scatter Occurs
|
Below the Threshold For Ionization
|
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Energy At Which Photoelectric Effect Occurs
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Photon Energies At Or Below 1 MeV
|
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Energy At Which Incoherent or Compton Scatter Occurs
|
Most Radiation Treatment Energies
|
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Energy At Which Pair Production Occurs
|
Above 1.022 MeV
|
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Energy At Which Photodisintegration Occurs
|
Photon or Electron Beam Energies At or Greater Than 10 MeV
|
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Thomson or Coherent Scatter
|
Photon Is Absorbed and Photon of Same Energy Is Emitted In a Different Direction
|
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Photoelectric Effect
|
Incident Photon Penetrates Deep Into the Atom and Ejects an Inner Shell Electron From Orbit
|
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Compton or Incoherent Scatter
|
Photon Ejects Outer Shell Orbital Electron and Alters Its Own Path, Generally Resulting In the Freed Electron Attaching Itself To Another Atom Shortly Thereafter
|
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Pair Production
|
Photon Approaches Nucleus, Is Absorbed and Then Emitted As An Electron-Positron Pair Which Is Ejected By the Atom
|
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Phenomenon Associated With Positron Created During Pair Production
|
Slows Down and Creates Annihilation Reaction, Destroying Both Positron and Electron and Leaving Two Photons Emitted Opposite Each Other Out of Their Energy
|
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Photodisintegration
|
Photon Is Absorbed After Striking the Nucleus Directly, Which Then Emits Neutrons and Gamma Rays to Maintain Stability
|
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|
Atomic Number of Substances Involved In Photodisintegration
|
High Z Materials
Generally Not Tissue, But Beam Production Devices Within High Energy Linear Accelerators, Responsible For Neutron Production In These Cases |
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Form of Neutron Shielding
|
Borated Plastic To Slow Down Neutrons and Allow For Their Capture
|
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Skin Exposure At Double the SSD
|
1/4 That Of the Original SSD
|
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Half Life Equation
|
Half Life = .693 / decay constant
|
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Decay Constant Equation
|
- Decay Constant = Change in Number of Atoms / Change in Time
|
|
|
Radioactivity Equation
|
Activity = Initial Activity x e^(- decay constant)(time)
|
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|
Mean Life Equation
|
Mean Life = Half Life x 1.44
|
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Effect of Protraction Rate On Relative Biologic Effectiveness
|
Faster Protraction Rate Results in Greater RBE
|
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Effect of Quality Factor On Relative Biologic Effectiveness
|
Higher Quality Factor Results in Greater RBE
|
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Acceptance Criteria For Amount Of the Beam Transmitted Through the Beam Interceptor
|
Less Than 0.5% 1 m From The Housing
|
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Relationship Between Therapeutic Ratio and Relative Biologic Effectiveness
|
Higher Values for Therapeutic Ratios Result In Greater Relative Biologic Effectiveness
|
|
|
Structures With Radiation Tolerance Greater Than 7000 cGy
|
Vagina
Articular Cartilage Aorta |
|
|
Tolerance Dose of Ovary and Endpoint
|
200-300 cGy
Sterility |
|
|
Condition Associated With Renal Insufficiency in Patients Who Undergo Pediatric Irradiation
|
Hypertension
|
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Dmax for 1.25 MV Beam
|
1/2 cm
|
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|
Dmax for 4 MV Beam
|
1 cm
|
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Dmax for 6 MV Beam
|
1 1/2 cm
|
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|
Dmax for 10 MV Beam
|
2 1/2 cm
|
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Dmax for 18 MV Beam
|
3 1/2 cm
|
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Dmax for 24 MV Beam
|
4 cm
|
|
|
Percent Depth Dose Equation
|
PDD = Absorbed Dose at Depth / Absorbed Dose at Dmax x 100%
|
|
|
Mayneord's Factor Equation
|
F Factor = [(SSD2 + Dmax)/(SSD2 + Depth)]^2 / [(SSD1 + Dmax)/(SSD1 + Depth)]^2
New PDD = Old PDD x Mayneord F Factor |
|
|
When to Use Mayneord F Factor
|
To Determine PDD When Treating Using Different Distances
|
|
|
When to Use Inverse Square Law
|
To Determine Exposure When Treating Using Different Distances
|
|
|
Equivalent Square Formula
|
Area / Perimeter = Area / Perimeter
Equivalent Square = 4 (A/P) |
|
|
Means of Localizing Pancreatic Cancers
|
Surgical Clips
|
|
|
Conformal Radiation Treatment
|
Using 3D Planning to Deliver Radiation to the Exact Target Volume In Any Plane
|
|
|
Gap Calculation Formula
|
Gap = (1/2)(Length1)(Depth1)/(SSD1) + (1/2)(Length2)(Depth2)/(SSD2)
|
|
|
Device Used To Correct an Oblique or Curved Skin Surface Approximated With a Straight Line
|
Compensating Wedges
|
|
|
Fields Used For Esophagus Treatment
|
AP/PA and Oblique Opposed Fields
|
|
|
Depths Usually Treated Using Wedge Pair Fields
|
A Few cm Below Skin Surface
|
|
|
Dmax Equation
|
Dmax = (DD / PDD)(100)
|
|
|
Common Cerrobend Block Thickness Treating Using MV
|
7 1/2 cm
|
|
|
Acceptable Amount of Beam Transmission Through a Block
|
5%
|
|
|
Limitations of Ultrasound
|
Waves Reflected By Air, Limiting Use With Structures That Contain or Are Surrounded By Air
|
|
|
Reason Compensators Should Remain 15 cm or Further From the Patient's Skin
|
To Preserve Skin Sparing
|
|
|
Purpose of Scattering Foil
|
More Homogeneous Dose Distribution When Treating Curved Surfaces Being Treated Using Electrons
|
|
|
Beam Energy Plane Parallel Ionization Chambers Are Calibrated To
|
20 MeV
|
|
|
Device Used to Measure Electron Beams for TG-21 Protocol
|
Plane Parallel Ionization Chamber
|
|
|
Application of Coefficient of Equivalent Tissue
|
To Correct For Tissue Inhomogeneities By Equating Them To Equivalent Thickness In Water
|
|
|
Most Common Side Effects From Palliative Radiation Therapy to the Brain
|
Cerebral Edema
May Lead to Memory Impairment |
|
|
Factors That Impact Backscatter Factor
|
Beam Quality
Field Size and Volume Being Irradiated |
|
|
Effects Of Increased Field Size
|
Higher Dose To the Buildup Region
Less Skin Sparing |
|
|
Equivalent Depth of Calibration for MV Photons Up To 6 MV
|
5 cm Water
|
|
|
Factors Influencing TAR at Depth of Dmax
|
Depth
Size Of Field Less Significant |
|
|
Relationship Between Isodose Depth and Beam Quality
|
Directly Proportional
|
|
|
Effect Of Beam Energy On Penumbra
|
Higher Energy Results in Wider Penumbra
|
|
|
Effect of Field Size On Penumbra
|
Larger Field Size Results in Wider Penumbra
|
|
|
Maximum Dose For Hot Spots In Wedge Pair Treatments
|
10%
|
|
|
Interface Which Results In Most Echo Reflection During Ultrasound
|
Soft Tissue vs. Bone Interface
|
|
|
Site Most Likely to Metastasize To the Liver vs. Other Sites
|
Gastrointestinal
|
|
|
Site Most Likely to Metastasize To the Liver Overall
|
Breast
|
|
|
Endocrine Function of the Kidney
|
Release of Renin Involved With Blood Pressure Regulation
|
|
|
Least Radiosensitive Structure In the Gastrointestinal System
|
Esophagus
|
|
|
Most Common Histology Within the Aerodigestive Tract
|
Squamous Cell Carcinoma
|
|
|
Functions of Lucite Shadow Trays
|
Absorption Of Electron Contamination Within the Beam
Modification Of the Build Up Curve, Being Used As a Beam Spoiler |
|
|
Normal Tolerance Dose Of Radiation Nephropathy
|
2000 cGy
|
|
|
Location Of the Ovaries
|
Medial To the Ureter
|
|
|
Bone Remodeling Cycle
|
Involves Resorption and Formation of Bone Mass
|
|
|
Potential Complications Of Irradiation During Adolescence
|
Slipped Femoral Capital Epiphysis
Maturation Abnormalities of the Bone and Soft Tissue |
|
|
Bodily Fluids Composed Predominantly Of Water and Methylcellulose
|
Saliva
Tears Aqueous Humor |
|
|
Therapies Associated With the Complication of Pneumonitis
|
Radiation Therapy
Cyclophosphamide Doxorubicin |
|
|
Shoulder Of Survival Curve
|
Dose Below Which Cells Generally Are Not Accumulating Enough Damage To Be Killed
|
|
|
Linear Part of Survival Curve
|
Semilogarithmic Representation Indicating Equal Increases in Dose Result in Equal Decreases in Surviving Fraction Of Cells, With Actual Number Of Cells Varying
|
|
|
Extrapolation Number
|
Represented By n
Intersection Of Linear Part of Curve Extrapolated to the Y-Axis Suggests Number Of Targets That Must Be Hit To Kill Cell Range From 2 - 10 For Mammal Cells |
|
|
Quasithreshold Dose
|
Represented By Dq
Dose At Which Survival Becomes Exponential Width Of the Shoulder On the Survival Curve Dose At Surviving Fraction of 1 Measure Of a Cell's Ability to Accumulate and Repair Sublethal Damage |
|
|
Dose
|
Represented By Do or D37
Reduces Surviving Fraction Of Cells to 37% Reciprocal Of the Slope of the Linear Part of the Curve Measure Of Cell's Radiosensitivity Proportional to Radioresistance Usually Between 100 - 220 cGy For Mammal Cells |
|
|
Survival Curve Equation
|
log(e) n = Dq / Do
|
