[Trans Anatomy] Introduction to Medical Imaging - Vocabulary Flashcards

Comprehensive vocabulary flashcards covering fundamental medical imaging principles, anatomical orientations, radiologic modalities (X-ray, Ultrasound, CT, MRI, Nuclear Medicine), attenuation mechanics, and signal intensity terminology based on Module 1 notes.

Medical Imaging

A field of medicine that utilizes technological advances to generate visual representations of internal body structures without gross surgery, serving diagnosis, treatment guidance, and monitoring.

Wilhelm Conrad Röntgen

The physicist who accidentally discovered X-rays in $1895$, produced the first radiograph using his wife's hand, and received the first Nobel Prize in Physics in $1901$.

Egas Moniz

The medical pioneer who introduced angiography in $1927$.

Ian Donald

The medical pioneer who introduced ultrasound into clinical practice in $1955$.

Sir Godfrey Hounsfield

The inventor who introduced Computed Tomography (CT) in $1971$.

Paul Lauterbur and Sir Peter Mansfield

The researchers who developed Magnetic Resonance Imaging (MRI) in $1976$.

Vitruvian Man

A famous drawing by Leonardo da Vinci illustrating human anatomical proportions, though not used as a modern standard anatomical model.

Standard Anatomic Position

The reference posture where an individual stands upright with head, eyes, and toes directed forward, upper limbs at the sides with palms facing forward and thumbs pointing outward, lower limbs parallel, feet flat on the floor, and penis flaccid in males.

Supine Position

Anatomic position in which the patient lies horizontally on their back with the face and anterior surface facing upward.

Prone Position

Anatomic position in which the patient lies horizontally on their stomach with the face and posterior surface facing downward.

Right Lateral Recumbent Position

Anatomic position in which the patient lies horizontally on their right side, facilitating access to organs located on the left side of the body.

Left Lateral Recumbent Position

Anatomic position in which the patient lies horizontally on their left side, facilitating access to organs located on the right side of the body.

Axial Plane

Horizontal cardinal plane perpendicular to the long axis of the body that divides the body into superior and inferior portions.

Coronal Plane

Vertical cardinal plane running from side to side that divides the body into anterior and posterior portions.

Sagittal Plane

Vertical cardinal plane running from front to back that divides the body into right and left halves.

Anterior

Anatomical term of relation denoting a position toward or at the front of the body (also termed ventral).

Posterior

Anatomical term of relation denoting a position toward or at the back of the body (also termed dorsal).

Superior

Anatomical term of relation denoting a structure located closer to the head or upper part of the body (also termed cranial or cephalad).

Inferior

Anatomical term of relation denoting a structure located closer to the feet or lower part of the body (also termed caudal).

Medial

Anatomical term of relation referring to a position toward the midline of the body.

Lateral

Anatomical term of relation referring to a position farther away from the midline of the body.

Proximal

Anatomical term describing a location nearer to the trunk or point of origin of a limb.

Distal

Anatomical term describing a location farther away from the trunk or point of origin of a limb.

Ipsilateral

Term describing structures located on the same side of the body.

Contralateral

Term describing structures located on opposite sides of the body.

Radiopharmaceuticals

Radioactive elements conjugated with drugs or chemicals that exhibit specific organ or tissue affinities, used in nuclear medicine for diagnostic imaging or therapy.

Gamma Camera

An imaging device in nuclear medicine that detects gamma radiation emitted from radiopharmaceuticals inside a patient and converts it into diagnostic images.

Bone Scan

A nuclear medicine procedure using radiopharmaceuticals targeted to sites of active bone metabolism to detect primary bone cancers or metastatic lesions.

Thyroid Scan

A nuclear medicine technique utilizing thyroid-selective radiotracers to evaluate gland uptake, function, and pathological nodules.

PET/CT Scan

A hybrid modality combining Positron Emission Tomography and CT, using radioisotope-tagged glucose to pinpoint hypermetabolic and hypercellular tissues such as tumors.

Myocardial Perfusion Imaging

A nuclear medicine diagnostic test assessing coronary blood flow by comparing heart radiotracer uptake during exercise stress and rest conditions.

Echocardiography

A cardiovascular ultrasound procedure evaluating cardiac structural integrity, chamber dimensions, pressures, and flow velocities via Doppler principles.

Vascular Ultrasound

Non-invasive ultrasound technique evaluating blood vessel lumen patency and flow velocities in peripheral limbs and carotid arteries.

Interventional Cardiology

A branch of cardiology using X-ray fluoroscopy guidance to evaluate vessel obstruction and perform therapeutic procedures within the heart.

Interventional Radiology

A medical subspecialty using cross-sectional imaging (CT or ultrasound) to guide minimally invasive diagnostic biopsies and non-cardiac therapeutic interventions.

X-ray

High-frequency, high-energy invisible electromagnetic radiation produced when high-speed electrons strike an anode target.

X-ray Attenuation

The total reduction in the intensity of an X-ray beam as it passes through matter, caused by absorption and scattering processes.

Radiopacity

The physical property of a structure to absorb X-rays, resulting in a lighter or white appearance on a radiograph.

Radiolucency

The physical property of a structure permitting X-ray penetration, resulting in a darker or black appearance on a radiograph.

Postero-Anterior (PA) Projection

Standard chest X-ray projection where the beam enters the patient's back (posterior) and exits through the front (anterior) onto the image receptor.

Antero-Posterior (AP) Projection

X-ray projection where the beam enters the anterior surface and exits posteriorly, commonly reserved for bedridden or severely ill patients.

Lateral Projection

X-ray projection directed perpendicular to the sagittal plane and parallel to the coronal plane, passing from one side of the body to the other.

Fluoroscopy

A diagnostic imaging technique utilizing continuous X-ray beams to produce real-time moving images of internal anatomical structures.

Digital Subtraction Angiography (DSA)

An advanced X-ray technique that mathematically subtracts a pre-contrast radiograph from a post-contrast radiograph to isolate contrast-filled blood vessels.

Piezoelectric Effect

The physical property of certain crystals (such as quartz) to generate an electrical charge when mechanically compressed, or to vibrate when subjected to an electric field.

Sonologist

A licensed medical doctor who specializes in acquiring, supervising, and interpreting ultrasound studies.

Sonographer

A radiologic technologist specially trained to perform ultrasound examinations on patients.

Echogenicity

The characteristic capacity of a tissue to reflect sound waves back toward the ultrasound transducer.

Anechoic

Ultrasound term describing a structure that produces no echoes, appearing completely black on the screen (e.g., fluid-filled cysts or urinary bladder).

Hypoechoic

Ultrasound term describing a tissue that generates fewer echoes and appears darker than adjacent surrounding structures.

Isoechoic

Ultrasound term describing a structure that generates an echo intensity identical to surrounding reference tissues.

Hyperechoic

Ultrasound term describing a structure that reflects a high proportion of sound waves, appearing brighter than adjacent tissues.

Acoustic Enhancement

An ultrasound artifact where tissues located posterior to a low-attenuating fluid-filled structure appear brighter (hyperechoic) than adjacent tissues.

Acoustic Shadowing

An ultrasound artifact characterized by a dark signal drop-out region behind a dense or highly reflective object (such as a gallstone or bone) that attenuates sound.

Doppler Effect

The change in observed wave frequency resulting from relative motion between an emitter/reflector and an observer, applied in ultrasound to map blood flow velocity.

Computed Tomography (CT)

An imaging modality using a rotating X-ray source and computer algorithms to generate tomographic cross-sectional slices and 3D reconstructions.

Hounsfield Units (HU)

A standardized quantitative scale measuring tissue radiodensity on CT scans, anchored with water at $0$\,HU, air at $-1000$\,HU, and dense metal at $+1000$\,HU.

Pixel

The basic two-dimensional square picture element forming digital radiologic images.

Voxel

The three-dimensional volumetric counterpart of a pixel, representing a specific block of tissue volume in tomographic imaging.

Contrast Media

Chemical formulations administered IV, orally, or rectally to highlight specific organ tissues or blood vessels by altering local contrast resolution.

Endoluminal CT

A CT application using gas distension inside hollow organs to generate 3D internal walkthrough reconstructions (e.g., virtual colonoscopy).

Dual Energy CT

An advanced CT technique acquiring data at two distinct X-ray energy spectra to differentiate tissue chemical compositions such as kidney stone types or acute bone edema.

Magnetic Resonance Imaging (MRI)

A non-ionizing cross-sectional imaging technique exploiting the behavior of hydrogen nuclei placed inside strong magnetic fields and excited by radiofrequency pulses.

Precession

The rotational wobbling motion of the spin axis of atomic nuclei (such as hydrogen protons) around a external magnetic field vector.

T1-Weighted Image

An MRI sequence driven by spin-lattice relaxation that offers optimal anatomical soft-tissue detail, where fat appears hyperintense (bright) and water appears hypointense (dark).

T2-Weighted Image

An MRI sequence driven by spin-spin relaxation designed primarily for pathology detection, where fluid and water appear hyperintense (bright).

Short Tau Inversion Recovery (STIR)

A T2-weighted MRI pulse sequence that selectively suppresses fat signals to highlight fluid and edema in musculoskeletal conditions.

Fluid Attenuation Inversion Recovery (FLAIR)

A T2-weighted MRI pulse sequence that suppresses hyperintense cerebrospinal fluid (CSF) signals to clarify periventricular brain lesions.