Principles of 2D and M-Mode Echo (Continued) Flashcards
(38 cards)
Calculate the reflection co-efficient for the muscle air interface.
0.0004 x106 + 1.71x106
In echocardiography or medical ultrasound imaging in general, we encounter various types of reflectors, some of which are specular (reflecting waves in a specific direction) and others are non-specular (reflecting waves in multiple directions). Here are some examples:
Specular Reflectors:
Heart valve leaflets: These thin structures within the heart can produce specular reflections due to their smooth surfaces.
Diaphragm: The diaphragm separating the chest and abdominal cavities can produce specular reflections, especially in cases of pleural effusion or pneumothorax.
Bone surfaces: Bone surfaces can act as specular reflectors, particularly when the ultrasound beam encounters cortical bone interfaces.
Non-Specular Reflectors:
Myocardium: The muscular tissue of the heart can produce non-specular reflections due to its irregular structure and varying orientation of muscle fibers.
Blood cells: Within the bloodstream, red blood cells can scatter ultrasound waves in multiple directions, leading to non-specular reflections.
Liver parenchyma: Liver tissue can produce non-specular reflections due to its heterogeneous structure and presence of blood vessels.
What position should the patient typically lay in to obtain the left parasternal views?
Correct answer:
left lateral decubitus
Semi-fowler
, Not Selected
right lateral decubitus
, Not Selected
Supine
What structures are visualised in the left parasternal long axis view of the left ventricle?
Correct answer:
Left ventricular outflow tract
Left atria
Mitral valve
What left ventricle wall is visualised in the left parasternal long axis view of the left ventricle?
Posterior
What anatomical structure is best visualised from the high left parasternal view?
Proximal ascending aorta
What normal variants can be seen in the right atria from the right ventricular inflow tract view?
Correct answer:
Chiari network
Eustachian valve
What are these: Review
Chiari network:
Moderator band (Septomarginal trabecula)
Atrial appendage
Eustachian valve (Valve of the inferior vena cava)
Chiari network: This is a reticulated network of fibers or strands in the right atrium. The Chiari network is a web-like structure of fibers or strands found in the right atrium of the heart, thought to be a remnant of embryonic development, which may play a role in directing blood flow during fetal circulation. In adults, it typically has no significant physiological function but may be observed incidentally during imaging studies or cardiac procedures.
Moderator band (Septomarginal trabecula): This is a muscular band of tissue found in the right ventricle. While not directly visible in the right atrium.
The moderator band, also known as the septomarginal trabecula, is a muscular structure found in the right ventricle of the heart, extending from the interventricular septum to the base of the anterior papillary muscle. It contains the right bundle branch of the cardiac conduction system and helps coordinate ventricular contraction, contributing to efficient pumping of blood from the right ventricle.
Atrial appendage: The right atrial appendage is a small, ear-shaped pouch-like structure extending from the right atrium.
The atrial appendage assists in optimizing atrial function by increasing atrial capacity and aids in preventing blood stasis by serving as a reservoir for blood, thus reducing the risk of clot formation in the atria.
Eustachian valve (Valve of the inferior vena cava): This is a fold of tissue at the opening of the inferior vena cava into the right atrium.
The Eustachian valve is a fold of tissue located at the opening of the inferior vena cava into the right atrium of the heart, directing oxygenated blood towards the foramen ovale during fetal development. In adults, it may have a minimal physiological role, potentially influencing blood flow dynamics in certain clinical conditions such as atrial septal defects.
In the left parasternal long axis view of the left ventricle, the left ventricle should be —————– to the sound beam and be —————– in the sector.
–Perpendicular–
–Horizontal–
The interatrial septum can be best visualised in which of the following parasternal views?
Parasternal short axis of the aortic valve
Axial resolution is the:
A)Minimum reflector spacing along the axis of an ultrasound beam that results in separate distinguishable echos being displayed
B)Minimum reflector spacing perpendicular to the axis of an ultrasound beam that results in separate distinguishable echos being displayed
C) Ability to accurately image moving structures
D) Smallest variation in echo level that can be distinguished as a shade of grey on B-mode
Minimum reflector spacing along the axis of an ultrasound beam that results in separate distinguishable echos being displayed
Lateral resolution is the:
A)Minimum reflector spacing along the axis of an ultrasound beam that results in separate distinguishable echos being displayed
B)Minimum reflector spacing perpendicular to the axis of an ultrasound beam that results in separate distinguishable echos being displayed
C) Ability to accurately image moving structures
D) Smallest variation in echo level that can be distinguished as a shade of grey on B-mode
Correct answer:
Minimum reflector spacing perpendicular to the axis of an ultrasound beam that results in separate distinguishable echos being displayed
Contrast resolution is the:
A)Minimum reflector spacing along the axis of an ultrasound beam that results in separate distinguishable echos being displayed
B)Minimum reflector spacing perpendicular to the axis of an ultrasound beam that results in separate distinguishable echos being displayed
C) Ability to accurately image moving structures
D) Smallest variation in echo level that can be distinguished as a shade of grey on B-mode
D) Smallest variation in echo level that can be distinguished as a shade of grey on B-mode
Temporal resolution is the:
A)Minimum reflector spacing along the axis of an ultrasound beam that results in separate distinguishable echos being displayed
B)Minimum reflector spacing perpendicular to the axis of an ultrasound beam that results in separate distinguishable echos being displayed
C) Ability to accurately image moving structures
D) Smallest variation in echo level that can be distinguished as a shade of grey on B-mode
C) Ability to accurately image moving structures
In order for two reflectors to be displayed as two separate reflectors in the axial plane what must be true?
They must be separated by spatial pulse length
They must be separated by less than one wave length
They must be separated by less than one spatial pulse length
They must be separated by one wave length
Answer,
They must be separated by less than one spatial pulse length
Where is the best lateral resolution on the sound beam?
Focal-point
Near-field
, Not Selected
Far-field
, Not Selected
Center of the beam
Focal-point
Frame rate depends on all of the following EXCEPT:
Propagation speed
, Not Selected
Number of scan lines
, Not Selected
Depth of reflector
Wavelength
Correct answer:
Wavelength
The increased the frame rate of an image you must:
Increased the sector width
Increased the depth
Decreased the sector width
Decrease the depth
Correct answer:
Decreased the sector width
Decrease the depth
Which direction do you tilt the probe to see that 5 chamber view from the 4 chamber view?
A)Posterior
B)Anterior
C)Inferior
D)Medially
Correct Answer:
Anterior
Which septum is visualised in the apical 5 chamber view?
A)Anterior
B)Posterior
C)Lateral
D)Inferior
E)Anterior
A)Anterior
Which septum and left ventricular wall are visualised in the apical long axis?
A)Anterior septum and inferior wall
B)Anterior septum and posterior wall
C)Inferior septum and posterior wall
D)Inferior septum and inferior wall
Correct answer:
Anterior septum and posterior wall
In the apical 2 chamber view, the………. wall is visualised on the left hand side of the sector and the………. wall is visualized on the right hand side of the sector.
In the apical 2 chamber view, the…..
inferior wall is visualised on the left hand side of the sector and the….
anterior wall is visualized on the right hand side of the sector.
What structures are seen in the apical long axis view?
A) Right ventricular inflow tract
B) Mitral valve
C) Left ventricular outflow tract
D) Left atrium
Correct answer:
Mitral valve
Correct answer:
Left ventricular outflow tract
Correct answer:
Left atrium
In the apical 4 chamber view the ………….
septum and …………….
wall are visualised.
In the apical 4 chamber view the
inferior septum and lateral
wall are visualised.
