Chapter 2 Flashcards
What does the bony thorax consist of?
The bony thorax consists of the 2 clavicles, 2 scapulae, the 12 pairs of ribs, and the 12 thoracic vertebrae posteriorly.
Radiographic anatomy of the chest is divided into three sections:
Radiographic anatomy of the chest is divided into three sections: bony thorax, respiratory system proper, and mediastinum.
These topographic landmarks should be parts of the body that are easily and consistently located on patients, such as parts of the bony thorax. For chest positioning, two of these landmarks are
the vertebra promi-nens and the jugular notch
The midthorax, at the level
T7
inferior tip of the sternum, the xiphoid process is at the level of (vertebrae)
T9-T10
Four general divisions of the respiratory system, are the
pharynx, trachea, bronchi, and lungs.
serves as a passageway for food and fluids as well as air, making it common to the digestive and respiratory systems.
pharynx
The pharynx is approximately consists of three divisions,
nasopharynx (na”-zo-far-inks), oropharynx o-ro-far-inks), and laryngopharynx (lah-ring”-go-far-inks).
this marks the boundary between the nasopharynx and the oropharynx.
uvula (ư-vu-
The upper margin of the larynx is at the approximate level of
C3
where the larynx joins with the trachea, is at the level of
C6
laryngeal prominence of the thyroid cartilage is located at the level of
C4-C5
The trachea, located just anterior to the esophagus, extends from its junction with the larynx at the level of C6 downward to the level of
T4-T5
AP and lateral radiographs of the upper airway allow visualization of the air-filled
trachea and larynx.
The trachea bifurcates at the
carina
The trachea bifurcates at the carina to form the
right and left primary bronchi
that the right bronchus divides into _ secondary bronchi, but the left divides into only _, with each entering individual lobes of the lungs.
right bronchus divides into three
left divides into only two
secondary bronchi continue to subdivide into smaller branches, called
bronchioles
For the right lung the _ fissure separates the inferior and middle lobes, whereas the _ fissure separates the superior and middle lobes.
oblique fissure separates the inferior and middle lobes
horizontal fissure separates the superior and middle lobes
The left lung has only two lobes-the superior (upper) and inferior (lower) -separated by a _ fissure.
single deep oblique
What has the is ability to store certain hormones and release them slowly to aid in the regulation of body metabolism. These hormones also help to regulate body growth and development, especially in children.
thyroid gland
What gland stores and secrete hormones that aid in specific blood functions, including maintenance of blood calcium levels by stimulating bone breakdown to increase calcium in the blood.
Parathyroid gland
The lungs are composed of a light, spongy, highly elastic substance called
parenchyma
This substance allows for the breathing mechanism responsible for expansion and contraction of the lungs, which brings oxygen into and removes carbon dioxide from the blood
lungs are composed of a light, spongy, highly elastic substance called parenchyma (pah-reng-ki-mah).
Each lung is contained in a delicate double-walled sac, or mem-brane, called the
pleura
The outer layer of this pleural sac lines the inner surface of the chest wall and diaphragm and is called the
parietal pleura.
The inner layer that covers the surface of the lungs, also dipping into the fissures between the lobes, is called the
pulmonary or visceral pleura
The potential space between the double-walled pleura, called the ___, contains a lubricating fluid that allows movement of one or the other during breathing.
pleural cavity
Air or gas present in this pleural cavity results in a condition called a __, in which air or gas pressure in the pleural cavity may cause the lung to collapse.
pneumothorax
Accumulation of blood in the pleural cavity creates a condition called a _, whereas fluid within the cavity is referred to as _.
Accumulation of blood in the pleural cavity creates a condition called a hemothorax, whereas fluid within the cavity is referred to as pleural effusion.
The _ of each lung is the rounded upper area above the level of the clavicles.
apex
The apices of the lungs extend up into the lower neck area to the level of _
This important part of the lungs must be included on chest radiographs.
T1 (first thoracic vertebra).
The _ is shown as the point of bifurcation, the lowest margin of the separation of the trachea into the right and left bronchi.
carina
The _ of each lung is the lower concave area of each lung that rests on the diaphragm
base
The _ is a muscular partition that separates the thoracic and abdominal cavities.
diaphragm
The _ refers to the extreme outermost lower corner of each lung, where the diaphragm meets the ribs.
costophrenic angle
The _, also known as the root region, is the central area of each lung, where the bronchi, blood vessels, lymph vessels, and nerves enter and leave the lungs.
hilum (hilus)
The right lung is usually about 1 inch (2.5 cm) shorter than the left lung. The reason for this difference is the __, which is located in the right upper abdomen and which pushes up on the right hemidiaphragm.
large space-occupying liver
The medial portion of the thoracic cavity between the lungs is called the ___.
mediastinum
Four radiographically important structures located in the mediastinum are the
1) thymus gland, (2) heart and great vessels,
(3) trachea, and (4) esophagus.
said to be a temporary organ because it is prominent in infancy and reaches its maximum size of about 40 g at puberty, then gradually decreases in size until it almost disappears in adulthood.
thymus gland
has a large role in the development of the immune system that helps the body resist disease. It is essential to the growth and development of thymic lymphocytes or T cells, which serve in rejecting things foreign to the body.
Thymus gland
The heart is located posterior to the body of the sternum and anterior to
T5 to T8
The great vessels in the mediastinum are the
inferior vena cava and superior vena cava, aorta, and large pulmonary arteries and veins.
The __ is a large vein that returns blood to the heart from the upper half of the body
superior vena cava
The __ is a large vein that returns blood from the lower half of the body.
inferior vena cava
The aorta is divided into three parts:
ascending aorta (coming up out of the heart); arch of the aorta; and descending aorta
The __, within the mediastinum, separates into the right and left primary and secondary bronchi,
trachea
increase the volume of the chest during inspiration the thoracic cavity increases in diameter in __ dimensions.
three; vertical diameter, transverse
diameter, anteroposterior diameter,
The first of these is the vertical diameter, which is increased primarily by __ movement of the dia-phragm, increasing the thoracic volume.
contraction and downward movement
The transverse
diameter is the second dimension that is
increased during inspiration. The ribs ___, and this increases the transverse diameter of the thorax.
swing outward and upward
The third dimension is the anteroposterior diameter, which is also increased during inspiration by the __ ribs, especially the second through sixth ribs.
raising of the ribs
During expiration, __ , causes the three diameters of the thorax to return to normal
the elastic recoil of the lungs, along with the weight of the thoracic walls
To determine the degree of inspiration in chest radiography, one should be able to
identify and count the rib pairs on a chest radio-graph.
general rule for average adult patients is to “show” a minimum of __ of ribs on a full inspiration PA chest radio-graph.
10 pairs
Patient preparation for chest radiography includes the removal
of all opaque objects from the chest and neck regions, including clothes with buttons, snaps, hooks, or any objects that would be visualized on the radiograph as a shadow
In general, chest radiography uses low contrast, described as long-scale contrast, with more shades of gray. This requires a high kVp of
110 to 125.
As a general rule, in chest radiography, the use of high kvp (> 100) requires the use of __
grids
Generally, chest radiography requires the use of __ mA and __ exposure time to minimize the chance of motion and resultant loss of sharpness.
high mA and short exposure time
Generally, with newborns and small infants, for whom head support is required, chest radiographs are taken
AP supine
For Peds chest X-ray __ kVp and __ mAs are required for pediatric patients with the shortest exposure time possible
lower kVp (70 to 85) and less mAs
Higher-speed imaging systems or receptors generally used for peds patients for 2 reasons:
1- to reduce chance of motion 2-reduce exposure dose
Frequently, older patients have less inhalation capability with resultant smaller lung fields, and a __ CR location is required
higher CR location is required (CR to T6-T7).
A bariatric patient may present positioning and centering chal-lenges. Because of a larger body girth, the technologist may place the top of the IR
1 to 2 inches (2.5 to 5 cm) above the shoulder.
T_ remains your centering point for most chest projections.
T7
T7 is generally located at the level of the
inferior angle of the scapula.
For the AP chest projection, the __ is a palpable landmark on the bariatric patient for a chest X-ray.
jugular notch
T7 is approximately __ inferior to the jugular notch.
3 to 4 inches (8 to 10 cm)
For a chest X-ray the patient should be asked to do what for respiration
hold the second full inspiration rather than the first.
Occasional exceptions have been noted to taking chest radiographs on full inspiration only. For certain conditions, __ radiographs are taken on both full inspiration (Fig. 2.31) and full expiration (Fig. 2.32).
comparison
All chest radiographs should be taken in an erect position if the patient’s condition allows. Three reasons for this are as follows:
The diaphragm is able to move down farther.
- Air and fluid levels in the chest may be visualized.
Engorgement and hyperemia of pulmonary vessels may be prevented. The
engorgement literally means
engorgement literally means “distended or swollen with fluid.”
Hyperemia (hy”-per-e-me-ah) is an excess
of blood that results in part from relaxation of the distal small blood vessels or arterioles. 3,4
If a patient has fluid in their lungs how will this look for an erect and recumbent X-ray
In the recumbent position, a pleural effusion spreads out over the posterior surface of the lung, producing a hazy appearance of the entire lung. In the upright position, free fluid is located near the base of the lung.
How does erect and supine chest positions effect engorgement and hyperemia of pulmonary vessels
An erect position tends to minimize engorgement and hyper-emia of
pulmonary vessels, whereas a supine position increases these, which can change the radiographic appearance of these vessels
Chest radiographs taken AP rather than PA at 72 inches (180 cm) result in __, which complicates the diagnosis of possible cardiac enlargement.
increased magnification of the heart shadow
A longer source-to-image receptor distance (SID), such as 72 inches (180 cm), magnifies less because
the x-ray beam has less divergence.
placing the heart closer to the IR on the PA results in
less magnification
Chronic obstructive pulmonary disease (COPD) is
a form of persistent obstruction of the airways that usually causes difficulty in emptying the lungs
emphysema or chronic bronchitis (smoking is the predominant cause of COPD) and Asthma
Cystic fibrosis (sis-tik fi-bro-sis), the most common of inherited diseases, is a condition in which
secretions of heavy mucus cause progressive “clogging” of bronchi and bronchioles.
Dyspnea (disp’-ne-ah) is a condition of
shortness of breath, which creates a sensation of difficulty in breathing;
PA and lateral Chest usually taken
Emphysema (em’-fi-se-mah) is an
irreversible and chronic lung disease in which air spaces in the alveoli become greatly enlarged as a result of alveolar wall destruction and loss of alveolar elasticity.
From dust and smoking
is evident on chest radiographs by increased lung dimensions, barrel chest with depressed and flattened diaphragm obscuring costophrenic angles, and an elongated heart shadow.
Lung neoplasm
refers to a new growth or tumor.
hamartoma
(ham”-ahr-to-ma) is the most
common
benign pulmonary mass, and it generally is found in peripheral regions of the lungs. These are seen on chest radiographs
Lung cancer may be demonstrated on chest radiography as
slight shadows in the early stages and as more sharply defined, larger radiopaque masses in more advanced cases.
Pneumothorax (noo-mo-thor-aks) is an accumulation
of air in the pleura space causes partial or complete collapse of the lung and results in shortness of breath
Chest radiographs for pneumothorax should be taken
erect. If the patient cannot assume an erect position, a horizontal beam lateral decubitus position with the affected side up should be taken (not down as with pleural effusion).
Pulmonary edema is a condition of
excess fluid within the lung that most frequently is caused by a backup in pulmonary circulation commonly associated with congestive heart failure.
A common cause is coronary artery disease,
The condition is seen on chest radiographs as a diffuse increase in radiodensity in the hilar regions fading toward the periphery of the lung
Respiratory distress syndrome (RDS) (commonly called hyaline membrane disease [HMD] in infants and adult respiratory distress syndrome [ARDS] in adults) is an emergent condition in which the
alveoli and capillaries of the lung are injured or infected, resulting in leakage of fluid and blood into the spaces between alveoli or into the alveoli themselves with formation of hyaline membranes.
This leakage can be detected radiographically as increased density (brightness) throughout the lungs
Tuberculosis (too-ber”-ku-lo-sis) (TB) is a (potentially fatal) contagious disease that is caused by
airborne bacteria.
Primary tuberculosis refers to TB that occurs in persons
who have never had the disease before. Hilar enlargement, along with enlarged mediastinal lymph nodes, is an important indicator of primary TB.
Reactivation (secondary) tuberculosis
usually develops in adults and is generally first evident on radiography bilaterally in the upper lobes as irregular calcifications that are mottled in appearance.
lordotic projections are frequently requested for visualization of calcifications and cavitations of the apices and upper lobes.
