Ultrasound Techniques PDF

- Transverse plane- probe is to the right - Longitudinal -- probe to the head - Echogenicity: - Hyperechoic -- white, bone, ligaments, dura, nerves - Isoechoic -- gray, muscles and muscle striation - Anechoic -- black, fluid, CSF, blood - Transducer points: - L...

- Transverse plane- probe is to the right - Longitudinal -- probe to the head - Echogenicity: - Hyperechoic -- white, bone, ligaments, dura, nerves - Isoechoic -- gray, muscles and muscle striation - Anechoic -- black, fluid, CSF, blood - Transducer points: - Linear- lower depth, higher resolution, good for superficial structures- vascular, nerves, lungs, ocular - Curvilinear- higher depth, lower resolution, abdominal, renal, OB - Phased away- higher depth, lower resolution, cardiac, lungs - Ultrasound modes - 2D or B-mode: most utilized setting, brightness mode, different shades of gray looking at 2D - M-mode: motion mode, captures ultrasound image in only one line of the 2D-mode image displayed over time; movement of structures positioned under that line are visualized - Color doppler: shows blood flow or tissue motion; red moves toward transducer and blue moves away from transducer - Pulsed doppler: venous flow demonstrates a more continuous, band like shape and arterial flow shows a more triangular shape - Power doppler: amplitudes of the returning frequency shifts; detects movement in very low flow states to better assess presence of blood flow - Ultrasound functions (gain and depth) - Gain: changes overall strength of returning echos, making the image brighter or darker - Depth: increases or decreases the depth of the ultrasound waves - Improving image acquisition: probe pressure, fanning/rocking, sliding, respiratory assistance - Ultrasound artifacts - Shadowing: caused by absorption of the ultrasound wave by a solid structure like a gallstone, kidney stone, or bone - Edge shadowing - Posterior enhancement: substance behind an echo-free substance, such as fluid, appear brighter. This is the reason why we want a full bladder when doing a pelvic ultrasound - Reverberation: lung ultrasound, ultrasound waves hit the lung pleura and the sound waves bounce between the two layers before returning to the transducer. "a-lines" - Comet tail: produced by the front and back of a very strong reflector, produced by an air bubble - Ring down: produced by fluid collection surrounded by air bubbles, "B-lines"; in order to be pathologic you need 3 in one view