Medical Radiation Sciences Lecture Review

Comprehensive flashcards covering Medical Radiation Sciences, including roles, equipment, safety, biology, ethics, and positioning.

Radiation Therapist

A practitioner who uses ionising radiation (e.g., X-rays, gamma rays) to treat cancer by destroying or shrinking tumours.

Radiographer

A professional who produces diagnostic radiographs using modalities like X-ray, CT, and fluoroscopy to answer clinical questions.

ALARA Principle

An acronym standing for 'As Low As Reasonably Achievable', used to minimise radiation exposure to patients and staff.

Nuclear Medicine Technologist

A practitioner who operates SPECT and PET equipment and prepares radiopharmaceuticals for diagnostic and therapeutic purposes.

Sonographer

A specialized practitioner requiring postgraduate qualifications who utilizes ultrasound modalities for imaging and is accredited by ASAR.

PACS

An acronym for Picture Archiving and Communication System, used for the secure storage, retrieval, and transmission of medical images.

Cathode

The part of the X-ray tube that emits electrons via a heated filament to initiate X-ray production.

Anode

The target in an X-ray tube where electrons strike to produce heat and X-rays.

kVp

Kilovoltage Peak; the factor that controls the energy and penetrability of the X-ray beam, affecting image contrast.

mA

Milliamperes; the unit that regulates the tube current and influences the quantity of X-rays produced.

SID

Source to Image Distance; the distance affecting image sharpness and intensity, typically ranging from $100\,\text{cm}$ to $180\,\text{cm}$.

Ionising Radiation

Radiation capable of removing electrons from atoms, leadion to ionization.

Carcinoma

The most common type of cancer, originating in epithelial cells that line organs and skin.

Sarcoma

A type of cancer arising from connective tissues such as bones, muscles, fat, and blood vessels.

Vascular Spread

A mechanism of cancer spread where cells enter the bloodstream to reach distant organs.

Thermionic Emission

The process where a filament is heated, causing electrons to 'boil off' and form an electron cloud for X-ray production.

Photoelectric Effect

An interaction where an inner-shell electron is ejected, resulting in total X-ray absorption and appearing white (high contrast) on a radiograph.

Compton Scatter

An interaction where an outer-shell electron is ejected, causing scattered X-rays and reduced image contrast.

Radiolucent

Structures that allow X-rays to pass through easily, appearing dark on a radiograph.

Radiopaque

Structures that absorb X-rays and appear white on the radiograph, indicating higher density.

Aseptic Technique

A method performed under sterile conditions to prevent infection during invasive medical procedures.

Penumbra

The blurry border around an object on a radiograph that indicates unsharpness.

Autonomy

The bioethical principle respecting a patient's right to make informed decisions about their own healthcare.

Non-maleficence

The bioethical principle underscoring the obligation to 'do no harm' to patients.

AHPRA

The Australian Health Practitioner Regulation Agency; the national regulator overseeing 15 health professions.

Computed Radiography (CR)

A digital imaging process utilizing photostimulable phosphor (PSP) plates to capture latent images.

Exposure Creep

The gradual increase in patient radiation dose due to clinician overexposure in digital imaging systems.

Gray (Gy)

The unit used to measure the absorbed dose of radiation.

Sievert (Sv)

The unit used to measure equivalent and effective radiation doses.

Deterministic Effects

Acute radiation effects that occur above a threshold dose ($>1000\,\text{mSv}$), such as skin burns.

Stochastic Effects

Chronic radiation effects with no threshold, where the probability (not severity) increases with dose, such as cancer.

Bucky Factor

The term describing the increase in mAs needed when using a grid to compensate for primary beam absorption.

Evidence-Based Practice (EBP)

The integration of the best current research evidence with clinical expertise and patient values to improve care.

Sthenic

The most common body habitus type (50%), characterized by an average build and a high, J-shaped stomach.

Trendelenburg Position

A patient position where the individual lies supine with the head lower than the feet, typically angled at $30^{\circ}$ below.

DP Projection

Dorsoplantar; an imaging projection used for the foot where the beam travels from the top (dorsal) to the bottom (plantar) surface.

Patslide

A rigid board used to bridge surfaces and safely transfer patients between beds or imaging tables.

DEXA

Dual-energy X-ray absorptiometry; the gold standard for measuring Bone Mineral Density (BMD) and assessing osteoporosis.

OPG

Orthopantomography; a 2D panoramic X-ray technique capturing a wide view of the jaw and teeth.

Pharmacokinetics

The study of how the body processes drugs, including absorption, metabolism, and excretion.

3C’s of Patient Safety

A protocol ensuring the Correct Patient, Correct Procedure, and Correct Site/Side.

Sacred Seven

The seven elements of clinical history: Localization, Chronology, Quality, Severity, Onset, Aggravating/Alleviating factors, and Associated symptoms.

IMACREAP

A systematic image evaluation checklist standing for Identification, Markers, Anatomy, Collimation, Relative positioning, Exposure, and Acceptability.