1 March 2013 PGI Chandigarh Dr Sarvesh Natani

 SONAR( sound navigation & ranging) in 1800’s  Ingle Edler& Carl Hertz 1 st recorded echo 1950 in sweden  CW 1963  Real time scanner 1965  PW 1970  st duplex pulse doppler scanner  1980 color doppler.

 Frequency (f) & wavelength (λ)  Propogation speed 1540m/s  Hz  1-10 million ( MHz) in echo  Upto 30 MHz for intracoronary imaging  Shorter λ higher f better resolution reduced penetration

 B mode or basic grey scale  Presets for echo automatically default to higher frame rates  Depth: start deep then decrease n focus on area of importance. try to get area of intrest in upper 2/3  Gain: How machine listens to returning echoes.  gain amplifies returning echo n image is brighter.  Can be over all or at depth called TGC.

 Zoom  Focus : optimises lateral resolution at given depth  Tissue Hamonics; Frame rate etc

 M mode: visualize moving thing in 1 dimension eg IVC, cardiac valves.  Doppler: uses frequency shift of sound waves to measure velocity  Color flow  Pulse wave  Continuous wave

A standard echocardiogram is also known as a Trans thoracic echocardiogram (TTE), or cardiac ultrasound. The subject is asked to lie in the semi recumbent position on his or her left side with the head elevated. The left arm is tucked under the head and the right arm lies along the right side of the body Standard positions on the chest wall are used for placement of the transducer called “echo windows”

 Described by size n shape of footprint.  Linear, curvilinear and phased array Phased array probe ;an electronically steered beam in a close array, generating an image that comes from a point and is good for getting between ribs such as in cardiac ultrasound. F 1-10MHz

1.Imaging requires the use of intercostal acoustic windows. 2.Probes with small “footprints.” 3.Phased or microconvex arrays are utilized for this reason. 4.Imaging in adults; lower frequencies (typically 2-4 MHz). 5.Curvilinear probes can be used to image the heart, especially in the subxiphoidview.However,

 Parasternal  Apical  Subcoastal  Suprasternal

 Translation  Rotation  Angulation  Heal- toe

Transducer position: left sternal edge; 2 nd – 4 th intercostal space Marker dot direction: points towards right shoulder Most echo studies begin with this view It sets the stage for subsequent echo views Many structures seen from this view

Transducer position: left sternal edge; 2 nd – 4 th intercostal space Marker dot direction: points towards left shoulder(90 0 clockwise from PLAX view) By tilting transducer on an axis between the left hip and right shoulder, short axis views are obtained at different levels, from the aorta to the LV apex. Many structures seen