Chapter 12: Methods of examination; Normal Anatomy, and Radiographic findings of Chest Disease Flashcards
Four basic features of proper radiographic technique:
Penetration
Inspiration
Rotation
Motion
How is rotation assessed?
relationship between a vertical line drawn midway between the medial cortical margins of the clavicular heads and one drawn vertically through the spinous processes of the thoracic vertebrae
How is appropriate inspiration assessed?
present when the apex of the right hemidiaphragm is visible below the tenth posterior rib.
How is proper penetration of xray assessed?
when there is faint visualization of the intervertebral disk spaces of the thoracic spine and discrete branching vessels can be identified through the cardiac shadow
the focus to film distance in AP technique
40 inches: results in magnification of intrathoracic structures
The apparent cardiac diameter in AP techniques increases by?
15 to 20% bringing the upper limit of normal CT ratio from 50% to 57% in AP
normal CT ration in AP xray?
57%
Result of AP projection on chest xray?
- Elevates the diaphragm-> compressing the lower lobes and decreasing lung volumes
- Gravitational effect evens the blood flow between upper and lower zones in supine patients- difficult to assess Pulmo HPN
- Widening of the upper mediastinum or “vascular pedicle”
- gravitational layering hides small effusions and pneumothorax
what is Dual energy subtraction?
a form of computed radiography that utilizes low-energy (60 keV) and high energy (120 keV) photons to produce selective bone and soft tissue images
position that that detects small effusions, characterize free flowing effusions on decubitus side and small pneumothorax on contralateral side
Lateral decubitus
Can detect focal or diffuse air trapping and eases detection of a small pneumothorax
Expiratory radiograph
Improves visualization of the apiceswhich are obscured on routine PA xray by the clavicles and first costochondral junctions
Apical lordotic view
used to mainly assess chest dynamics on patients with suspected diaphragmatic paralysis now replaced by CT
chest flouroscopy
the major advantages of MRI?
- superior contrast resolution between tumor and fat
- ability to characterize tissues on the basis of T1 and T2 relaxation times
- the ability to scan in direct sagittal and coronal planes
- the lack of need for IV iodinated contrast
the major disadvantage of MRI?
unable to distinguish benign masses from malignant masses or lymph node
is an imaging modality based on he metabolic activity of neoplastic and inflammatory tissues
PET: Flourodeoxyglucose (FDG) PET
flat band of muscle and connective tissue of the cartilage
posterior tracheal membrane
lining epithelium of tracheal mucosa
Pseudostratified, ciliated columnar epithelium which contains scattered neuroendocrine cells (APUD)
The trachea is approximately __ cm long in adults
12 cm
the coronal tracheal diameter is __mm in men and __mm in women?
25 mm in men and 21 mm in women
in cross section the trachea is oval or horseshoe shaped with a coronal to sagittal diameter ratio of __?
0.6:1.0
A narrowing of the coronal diameter of the trachea with coronal-sagittal ratio of
saber sheath trachea seen in patients with COPD
A slight tracheal deviation to the right after entering the thorax can be a normal radiographic finding?
YES
the interface of the RUL with the right lateral tracheal wall is called ?
the right paratracheal stripe
the right paratracheal stripe should be uniformly smooth and should not exceed __mm in width
4mm in width
the left lateral tracheal wall is surrounded by mediastinal vessels and fat and is not normally visible in xray?
YES
the presence of air in the esophagus produces the ? represents the combined thickness of the tracheal and esophageal wall and intervening fat.. t
tracheoesophageal stripe
tracheoesophageal stripe thickness?
the ___ main bronchus is shorter than the ___ main bronchus (mean length of 2.2 and 5 cm respectively)
Right
Left
bronchioles bearing alveoli in their walls are termed?
respiratory bronchioles dividing into alveolar ducts and sacs
the airway just before the first repiratory bronchiole is the
terminal bronchiole= the smallest bronchiole without respiratory exchange structures
the lungs are divided by these invaginations of the visceral pleura?
interlobar fissures
Branches of the RUL
branches into 3 segmental branches: anterior, apical, posterior
Branches of the RML; arises from the intermediate bronchus
divided into medial and lateral branches. Blood supply by a branch of the right interlobar pulmonary artery
The RLL is supplied by the RLL bronchus and pulmonary artery. it is subdivided into .. segments
superior segment and 4 basal segments: anterior, lateral, posterior, and medial basal segments.
the LEFT lung is divided into upper and lower lobes by the what?
left major fissure
The LUL is analogous to the combined ___ lobes
RUL and RML
The LUL is subdivided into __ segments: namely?
4 segments namely: anterior, apicoposterior and the superior and inferior lingular segments
Blood supply of LUL?
anterior and apicoposterior segments= left main pulmonary artery.
Superior and inferior= superior and inferior lingular arteries are proximal branches of the left interlobar pulmonary artery analogous to the middle lobes blood supply.
The LLL segments?
superior segment and 3 basal segments: anteromedial, lateral, and posterior
gas exchanging units of the lungs?
alveolar ducts and sacs
pneumocytes that are flattened squamous cells covering 95% of alveolar surface
type 1
this pneumocytes are cuboidal cells capable of mitosis; source of new type of pneumocytes and provide mechanism for repair following alveolar damage. source of surfactant
type 2
the left major fissure begins more superiorly and has a slightly more vertical course than the right major fissure
YES
The minor fissure projects at the level of the right __th rib and is seen as a thin undulating line on frontal xray.
right 4th rib
the ___fissure is the most common accessory fissure and is found in 10 to 20% of individuals
inferior accessory fissure
the ___ fissure has been misidentified as the inferior pulmonary ligament and is responsible fro the juxtaphrenic peak(tenting) described in upper lobe volume loss.
inferior accessory fissure
the __ fissure is seen in 0,5% of individuals, represents the invagination of the right apical pleura by the azygos vein.
Azygos fissure
The __ fissure separates the superior segment from the basal segments of the lower lobe. On lateral it extends xray it extends posteriorly from the major fissure to the chest wall.
superior accessory fissure
The __ fissure is rarely seen normal variant that separates the lingula from the remaining portions of the upper lobe.
left main fissure
is a sheet of connective tissue that extends from the hilum superiorly to a level at or just above the hemidiaphragm, on CT it is a small laterally directed beak of mediastinal pleura adjacent to the esophagus
inferior pulmonary ligament
the inferior pulmonary ligament contains this vein superiorly
inferior pulmonary vein
This septum has been mistaken for the inferior pulmonary ligament. seen on CT near the inferior pulmonary ligament
sublobar septum
this ligament is a triangular density extending toward the lung that is seen along the posterior aspect of the right heart border on lung windows on chest CT
periocardiophrenic ligament
is an elastic artery that arises from the right ventricle at approximately 1 oclock position relative to the ascending aorta.
pulmonary arteries
are the primary nutrient vessels of the lung. They supply blood to the bronchial walls to the level of the terminal bronchiole
bronchial arteries
the two major lymphatic pathways in the lung and pleura
- The visceral pleural lymphatics
2. the parenchymal lymphatics
Is the scaffolding of the lung an as such provides support for the airways and pulmonary vessels
pulmonary interstitium
Edema involving this interstitium is recognized radiographically as peribronchial cuffing
axial interstium
Edema of this interstitium accounts for Kerley B Lines
peripheral and subpleural interstitium
is seen as a thin vertical line that overlies the thoracic spine
anterior junction line
a radio-lucent region regpresenting contact of the posterosuperior portions of the upper lobes
retrotracheal triangle
