Ultrasound Spring 2009 Student Final

Ultrasound AKA: 1)Diagnostic Medical Sonography 2)Sonography3) 4) Vascular Sonography 5)Echocardiography

Principles of Diagnostic Ultrasound NON- ionizing NON- ionizing Uses high frequency sound waves Uses high frequency sound waves By giving reflections from parts in the body By giving reflections from parts in the body ? Cost effective Cost effective ? Can be imaged in sectional, coronal and oblique planes Can be imaged in sectional, coronal and oblique planes

What makes a good Sonographer? Knowledge of detailed anatomy and Pathophysiology Knowledge of detailed anatomy and Pathophysiology 3D anatomy 3D anatomy Good communication Good communication Be able to work under stress Be able to work under stress

Repetitive Motion Injuries Poor ergonomic habits Poor ergonomic habits Poor equipment design Poor equipment design Poor posture Poor posture 80% have muscloskeletal injuries 80% have muscloskeletal injuries Shoulder (rotator cuff) Shoulder (rotator cuff) ? Neck Neck Lower Back Pain Lower Back Pain ? Eyesight problems Eyesight problems Why? Sustained pressure and force Sustained pressure and force ? Assisting with patient movement Assisting with patient movement ? Inadequate work breaks Inadequate work breaks Overall job stress Overall job stress

Still a Neonate Fairly new technology compared with x- ray Fairly new technology compared with x- ray First used for navy sonar in World War II First used for navy sonar in World War II 1940’s 1940’s US waves transmitted and returned US waves transmitted and returned

1947 – Through- Transmission Used to detect tumors and intracranial lesions Used to detect tumors and intracranial lesions With 2 transducers opposite sides of the head With 2 transducers opposite sides of the head Called through- transmission Called through- transmission

1948 First Ultrasound Douglas Howry

Contact Compound Scanner Tom Brown and Ian Donald Tom Brown and Ian Donald Obstetric techniques Obstetric techniques

Present Day Smaller machines Smaller machines Increased resolution Increased resolution Real time scanning Real time scanning Portable Portable Mobile Mobile

Properties of Sound Waves Acoustic waves Acoustic waves Energy that moves back and forth or vibrates at a steady rate Energy that moves back and forth or vibrates at a steady rate Audible sound waves Audible sound waves 16,000 – 20,000 cycles/sec 16,000 – 20,000 cycles/sec Ultrasound waves Ultrasound waves million cycles/sec million cycles/sec _____________ mechanical vibrations through a medium _____________ mechanical vibrations through a medium Transmitted by particles of gas, liquid or solid medium Transmitted by particles of gas, liquid or solid medium

Piezoelectric Effect AC applied across piezoelectric crystals AC applied across piezoelectric crystals Crystals grow an shrink Crystals grow an shrink Conversion of electrical energy to mechanical energy Conversion of electrical energy to mechanical energy US is produced from a transducer by this effect US is produced from a transducer by this effect

Acoustic Impedance Has properties similar to light Has properties similar to light Focused, refracted, reflected or scattered Focused, refracted, reflected or scattered Dependent on the density and elastic properties of medium Dependent on the density and elastic properties of medium Velocity of sound Velocity of sound Sound waves are sent and received Sound waves are sent and received Velocity is different among bone, air and soft tissue Velocity is different among bone, air and soft tissue Poor impedance in air Poor impedance in air Pitch and sound waves are picked up by computer and produce images: based on depths and speeds Pitch and sound waves are picked up by computer and produce images: based on depths and speeds

Types of Transducers

Elements of Transducers Capable of sending and receiving US Capable of sending and receiving US

Advantages of US 1. Ultrasound examinations can be non- invasive 1. Ultrasound examinations can be non- invasive 2. Ultrasound methods are relatively inexpensive, quick and convenient 2. Ultrasound methods are relatively inexpensive, quick and convenient 3. No harmful effects have been detected 3. No harmful effects have been detected 4. Ultrasound is particularly suited to imaging soft tissues 4. Ultrasound is particularly suited to imaging soft tissues

Disadvantages of US 1. The major disadvantage is that the resolution of images is often limited. 1. The major disadvantage is that the resolution of images is often limited. 2. Ultrasound is reflected very strongly on passing from tissue to gas, or vice versa 2. Ultrasound is reflected very strongly on passing from tissue to gas, or vice versa 3. Ultrasound also does not pass well through bone 3. Ultrasound also does not pass well through bone

Real Time, Doppler and Color Flow Doppler Real time: Real time: Multiple rapid image frames per second Multiple rapid image frames per second Ex: can see pulsative vascular, cardiac structures, diaphragm motion & peristalsis Ex: can see pulsative vascular, cardiac structures, diaphragm motion & peristalsis Doppler Doppler Frequency change in laminar or turbulent flow in vascular structures Frequency change in laminar or turbulent flow in vascular structures Color Doppler Color Doppler Assigns a color scale to change in frequency Assigns a color scale to change in frequency Red toward transducer and blue away from transducer Red toward transducer and blue away from transducer

Doppler

Color Doppler

Gallbladder

Gallbladder

Prostate

Prostate

Bladder

Kidney

Abdomen - LUQ

Abdomen - RUQ

Liver

Liver

Spleen

Spleen

Pancreas

Uterus

Uterus

Ovary

Ovary

Breast

Breast

Testes

19 Week Fetus

Heart

Heart