Cross Sectional Anatomy / CT Flashcards
a vertical plane that passes through the body, dividing it into right and left portions
Sagittal
a vertical plane that passes through the body, dividing it into anterior (ventral) and posterior (dorsal) portions
Coronal
a horizontal plane that passes through the body, dividing it into superior and inferior portions
Axial (transverse)
a plane that passes diagonally between the axes of two other planes
Oblique
on the opposite side
Contralateral
toward the feet
Caudal
toward a reference point or source within the body
Proximal
back of the knee
Popliteal
side of trunk adjoining the lumbar region
Flank
Where is the aortic arch located?
2.5cm below the jugular notch
What quadrant is the small intestine located in?
Most: LLQ Some: RUQ and RLQ
What part of the body does inguinal refer to?
Groin
What are the main cavities of the body?
Dorsal and Ventral
What are the subcategories of the dorsal cavity?
Located posteriorly and includes cranial and spinal cavities
What are the subcategories of the ventral cavity?
(largest) includes thoracic and abdominopelvic cavities
Ventral Cavity- Thoracic Cavity- _______ cavity and ________ cavity
2 lateral pleural, central mediastinum
Dorsal Cavity- Abdominal Cavity- _________ cavity and _______ cavity
abdominal, pelvic
Which parameter allows adjustment of the grey scale?
windowing - window width allows the adjustment of gray scale and window level sets the density of the image
Which CT number is used to refer to water?
Zero
What bone is the cribiform plate a part of?
ethimoid (also referred to as the horizontal portion)
Which facial bone forms the lower portion of the nasal septum?
vomer
What are the structures of the inner ear?
aka bony labyrinth- vestibule and semicircular canals. cochlea,
What bones form the largest portion of the sides of the cranium?
parietal
Which bones articulate with the parietal bones?
frontal, occipital, temporal and sphenoid
What structure houses the pituitary (hypophysis) gland?
sella turcica of sphenoid
What part of the inner ear is responsible for hearing?
cochlea
What is pia matter?
The inner layer of the arachnoid membrane- it is highly vascular and adheres closely to the contours of the brain
The lateral ventricles communicate inferiorly with the 3rd ventricle via the paired ___________ foramen.
interventricular (foramen of Monro)
What is gyri?
The cerebrum is the largest portion of the brain and is divided into left and right cerebral hemispheres. Each hemisphere contains neural tissue arranged in folds called gyri.
What are the major segments of the brainstem?
midbrain, pons, medulla oblongata
What area of the brain can be divided into the major segments: cerebral peduncles and tectum.
midbrain
How is the intervertebral foramina formed?
by the superior and inferior arches of the pedicles
The transverse processes of the sacrum join to form what?
lateral masses or ala
The ligamentum nuchae continues inferiorly as the what (in the cervical spine)
supraspinous ligament
What is the most inferior portion of the spinal cord called (at T12-L1)
conus medullarus
Which ventral rami does the brachial plexis arise from?
5 ventral rami of C5-C7 and T1
What are the largest pair of salivary glands?
parotid
How many unpaired cartilages make up the larynx
3
The pharangeal tonsils are also known as what
adenoids
The cricoid cartilage forms the base of what
larynx
The thyroid cartilage consists of laminae that unite anteriorly to form a shield to protect what?
vocal cords
What structures does the ooropharynx extend between
posterior extension of the oral cavity that extends from the soft palate to the level of the hyoid bone
At the level of the cricoid cartilage, the esophagus continues from the what?
descends through the thoracic cavity between the trachea and the anterior longitudinal ligaments of the vertebrae
When the true vocal cords are in a relaxed state they create an opening called the what
glottis
how many C shaped pieces of cartilage reinforce the trachea
16-20
What laryngeal cartilage is the thyroid gland located in
cricoid
How many levels or regions are the lymph nodes divided into
7
What CT plane divides the body into superior and inferior portions?
Axial plane
What CT planes divide the body into anterior and posterior portions
coronal plane
What CT plane divides the body into right and left portions
sagital plane
What controls the overall gray level and affects image contrast?
window width
What is the area of anatomy displayed on the monitor?
(can be adjusted to include entire body section or a specific part of the patient anatomy being scanned)
Field of View (FOV)
What is the individual pixel with the associated volume of tissue based on the slice thickness?
Voxel (volume element)
What is any noise in the image that is a result of random variation in the number of x-ray photons detected?
Quantum noise
What is the ability to identify visibly anatomic structures and small objects of high contrast?
Spatial Resolution
What is the ability of CT system to freeze motion of the scanned object? (the shortest amount of time needed to acquire a complete data set)
temporal resolution
What is data acquisition method that combines continuous gantry rotation with continuous table movement to form a helical path of scan data? (also known as spiral CT)
helical CT
What is another name for helical CT?
spiral CT
What is the number used to describe average density of tissue?
Hounsfield unit (HU)
What is the mathematical formula for calculation made up of individual cells for number assignment?
Matrix
What is the ability to differentiate between small variation in density?
contrast resolution
What is one individual cell surface within an image matrix used for image display?
pixel (picture element)
What is the electronic component of CT scanner that measures remnant radiation exiting the patient, converting the radiation to an analog signal proportionate to the radiation intensity measured?
detector assembly
What is a part of the detector assembly that converts analog signals to digital signals that can be used by the CT computer?
data acquisition system (DAS)
What is part of the CT scanner that houses x-ray tube, cooling system, detector assembly, and DAS?
gantry
What is the gantry often referred to as?
the doughnut
What is the electronic component used for radiation detection? (made of either high density photo reactive crystals or pressurized stable gases)
Detector
In CT what are the methods of contrast media administration?
intravenously
orally
rectally
Dose is affected by patient body size or body part?
body size
What are the three things for 3D reconstruction of an image?
construction
segmentation
rendering/shadowing
What part of 3D reconstruction:
a volume of 3D data from the original 2D CT image data?
construction
What part of 3D reconstruction:
crop or edit the target objects from the reconstructed data. (eliminates unwanted information from the CT data)
segmentation
What part of 3D reconstruction:
provides depth perception to the final image
rendering/shading
What are the 3 major components in CT?
-computer
-operating console
-gantry, patient table
