Chest Flashcards
Flat band of muscle and connective tissue that completes the posterior aspect of the trachea
Posterior tracheal membrane
Tracheal mucosa are composed of _____
Pseudostratified ciliated columnar epithelium
W/c contains scattered neuroendocrine(APUD) cells
*submucosa contains cartilage,smooth muscle and seromucous glands
Composed of the right lateral tracheal wall, a small amount of mediastinal fat, paratracheal lymph nodes, and the visceral and parietal pleural layers of the right upper lobe
-interface of the RUL with the right lateral tracheal wall
Right paratracheal stripe
- should be uniformly smooth,should not exceed 4mm in width
- thickness or nodularity reflects disease in any of the component tissues, including medial tracking pleural effusion
Normal TRACHEA approximate measurements:
A.length in adults
B. Upper limit of normal coronal diameter in men? In women?
C. Coronal-to-Sagittal diameter ratio
A. 12 cm.
B. 25 mm(men); 21 mm(women)
C. 0.6:1.0
A narrowing of the tracheal coronal diameter producing a coronal-to-Sagittal ratio of <0.6 is termed a _____
Saber sheath trachea
*seen in patients with COPD
Normal or abnormal?
Slight tracheal deviation to right after entering the thorax
Normal
- represents the combined thickness of the tracheal and esophageal walls and intervening fat
- produced by the presence of air in the esophagus
Tracheoesophageal stripe
- should measure less than 5mm
- thickening is commonly seen with esophageal ca
Bronchi gradually lose their cartilaginous support between generations ___ and _____
1;12 to 15
1-3mm airways
Bronchioles
Bronchioles bearing alveoli on their walls
Respiratory bronchioles
*divide into alveolar ducts and sacs
The airway just before the first respiratory bronchiole
-smallest bronchiole without respiratory exchange structures
Terminal bronchiole
Divides the lungs; invaginations of the visceral pleura
Interlobar fissures
Arises from the truncus anterior
Upper lobe bronchus and its artery
*3 segmental branches: anterior, apical, posterior
Arises from the intermediate bronchus
-supplied by a branch of the right interlobar pulmonary artery
Middle lobe bronchus
4 segments of the LUL
Anterior, apicoposterior(supplied by the upper division of the left main pulmonary artery), superior and inferior lingula segments
Gas exchanging units of the Lung
Alveolar ducts and alveolar sacs
*pulmonary alveolus is lined by type 1 (squamous) and type 2 (cuboidal) pneumocytes
The major and minor fissures are best visualized on _____ radiographs
Lateral
Left major fissure begins more ______ and has a slightly more ______ course than the right major fissure
Superiorly; vertical
Projects at the level of the right 4th rib and is seen as a thin undulating line on frontal radiographs in approx. 50% of individuals
Minor fissure
Most common accessory fissure ; approx 10% to 20% of individuals
-separates the medial basal from the remaining basal segments of the lower lobe, is often incomplete
Inferior accessory fissure
*a small triangle of extrapleural fat at its point of insertion in the diaphragm is a clue for identification
This is seen in 0.5% of individuals
- composed of 4 layers of pleura (2 viscera and 2 parietal)
- represents an invagination of the right apical pleura by the azygos vein
Azygos fissure
Separates the superior segment from the basal segments of the lower lobe
-distinguished from the minor fissure on lateral radiographs because it extends posteriorly from the major fissure to the chest wall
Superior accessory fissure (rare)
Separates the lingula from the remaining portions of the upper lobe
Left minor fissure
A sheet of connective tissue that extends from the hilum superiorly to a level at or just above the hemidiaphragm
- contains the inferior pulmonary vein superiorly and a variable number of lymph nodes
- accounts for the media, location and triangular appearance of lower lobe collapse
Inferior pulmonary ligament
- mistaken for the inferior pulmonary ligament
- a linear structure seen on CT near the inferior pulmonary ligament extending into the lung from mediastinal pleura
Sublobar septum
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
-represents a reflection of pleura over the inferior portion of the phrenic nerve and pericardiophrenic vessels
Pericardiophrenic ligament
The right interlobar artery course ANTEROLATERAL to the bronchus
EPIARTERIAL
…the LLL ARTERY over the left hilar bronchi
***page 332-333
HYPOARTERIAL bronchus
Primary nutrient vessels of the lung
Bronchial arteries
Usually arise from the POSTEROlateral wall of the aorta in common with an intercostal artery as an intercostobronchial trunk
Right bronchial artery
Arise individually from the ANTEROLATERAL aorta or rarely from an intercostal artery
Left bronchial arteries
Arise within the interlobular septa from the alveolar and visceral pleural capillaries
Pulmonary veins
When distended by fluid, these account for the radiographic appearance of Kerley A lines
Perivenous lymphatics and their surrounding connective tissue
Scaffolding of the lung , provides support for the airways and pulmonary vessels
Pulmonary interstitium
- axial interstitium(extends from the mediastinum and envelopes the bronchovascular bundles)
- centrilobular interstitium(provide support for the air-exchanging portions of the lung)
- peripheral interstitium(divides secondary pulmonary lobules,contains subpleural interstitium and interlobular septa)
Interstitium where pulmonary veins and lymphatics lie
Peripheral interstitium
A thin network of fibers that bridges the gap between the centrilobular and peripheral compartments
Intralobular interstitium
Edema involving the axial interstitium is recognized radiographically as ________
Peribronchial cuffing
Edema of the peripheral and subpleural interstitium accounts for ____
Kerley b lines and thickened fissures
Seen as sharp edges where the lung and adjacent pleura reflect off of various mediastinal structures
Lung-mediastinal interfaces
Relate directly to the space available in 3 regions viewed on the lateral film: retrosternal space, retrotracheal triangle, retrocardiac space
Lung-lung interfaces
An inferior extension of the upper lobe reflections off the inominate veins
-obliquely oriented from right superior to left inferior; extends from upper sternum to base of heart
Anterior junction line
A.Small retrotracheal triangle—–
B.Large retrotracheal triangle—–
A. Right paraesophageal interface
B. Posterior junction line (vertically oriented in the midline; extends from upper thoracic spine to level of azygos and aortic arches)
Large retrocardiac space—–
Inferior posterior junction line
Separates the right paraesophageal from the upper azygos esophageal space
Arch of the azygos vein
*measurement should be made thru the midpoint of the azygos arch perpendicular to the right main bronchus a diameter of greater than 10mm on a PA view should raise poss.of mass,adenopathy,or dilated arch of the azygos vein
2 conditions that will increase azygos venous diameter
- Supine positioning
2. Performance of the Muller maneuver (forced inspiration against a closed glottis)
Aortic nipple
-normally measures <5mm
Left superior intercostal vein
A vertically oriented interface overlying thoracic spine
Azygoesophageal recess interface
A line produced when air is present in the distal portion of the esophagus and the azygoesophageal recess interfaces with the right lateral wall of the esophagus
Right inferior esophagopleural stripe
A straight vertical interface extending the length of the right hemithorax and represents contact of the right lung with a small amount of tissue lateral to the thoracic spine
Paraspinal interface
Interface immediately inferior to the aortic arch
Aortopulmonary window
Immediately inferior to the Aortopulmonary window
Left lateral border of the main pulmonary artery
A reflection of the LLL with the esophagus anterior to the descending aorta,extending vertically from the undersurface of the aortic knob a variable distance toward the diaphragm
Preaortic recess interface
Represents the reflection of the left lung off the Paraspinal soft tissues
Left paraspinal interface
Forms a concave interface immediately below the main pulmonary artery
Left atrial appendage
Comprises most of the left heart border
Left ventricle
Fat adjacent to the cardiac apex
Epipericardial fat pad
The apex of the right hemidiaphragm typically lies at the level of the ________
6th anterior rib
*approx. 1/2 interspace above the apex of the left hemidiaphragm
Borders of the retrotracheal (or Raider) triangle
Posterior border of the trachea/esophagus, anterior border of the spine, top of the aortic arch
Impression on the anterior surface of the lingula
Cardiac incisura
Contains central cardiovascular, tracheobronchial structures, and esophagus enveloped in fat with intermixed lymph nodes
Mediastinum
A line drawn thru the _______anteriorly and __________ posteriorly divides the mediastinum into superior and inferior compartments
Sternal angle; 4th thoracic intervertebral space
A triangular or bilobed structure that is maximal in size at puberty and then undergoes gradual fatty involution
Thymus
Space seen between the trachea posteriorly and the posterior margin of the ascending aorta anteriorly and is contiguous with the precariously space inferiorly
Pretracheal space
4 contents of the Aortopulmonary window
Fat, lymph nodes, ligamentum arteriosum, left recurrent laryngeal nerve
Represents the junction of the lung with the mediastinum and is composed of upper lobe pulmonary veins and branches of the pulmonary artery and corresponding bronchi
Hilum
In more than 90% of individuals, the left hilar shadow is _______ than the right
Higher
The avascular aspect of the composite hilar shadow , inferior to the shadow of the right pulmonary arteries and veins and anterior to the descending left pulmonary artery and left superior vein
Inferior hilar window
A serosal membrane that envelopes the lung and lines the costal surface, diaphragm and mediastinum
Pleura
A potential space between the two pleural layers and normally contains a small amount of fluid (<5mL) that reduces friction during breathing
Pleural space
Diaphragmatic opening that lies in the midline, immediately behind the diaphragmatic crura and anterior to the 12th thoracic vertebral body
Aortic hiatus
Diaphragmatic opening that usually lies slightly to the left of midline, cephalad to the aortic hiatus
Esophageal hiatus
*transmits the esophagus and vagus nerves
Diaphragmatic opening that pierces the central tendon of the diaphragm at the level of the 8th thoracic intervertebral disk space
Inferior vena cava
Triangular gaps in the muscles of the anteromedial diaphragm
-site of potential intrathoracic herniation of abdominal contents
Foramina of Morgagni
Defects in the closure of the POSTEROlateral diaphragm at the junction of the pleuroperitoneal membrane with the transverse septum
Foramina of Bochdalek
Lines the ribs and endothoracic muscles
Endothoracic fascia
