front 1 Hyperechoic | back 1 structures or tissues that reflect much of the ultrasound energy back to the transducer and appear brightly on the image |
front 2 Hypoechoic | back 2 structures or tissues that reflect little of the ultrasound energy back to the transducer and appear darker on the image |
front 3 Anechoic | back 3 no reflection of energy -- appear darkest black |
front 4 tissues in order of echogenicity | back 4 cortical bone, tendon/ligament, nerve, muscle, subcortical bone. Noting normal expected views of tissues can allow for recognition of abnormalities, like a hypoechoic area of fluid around a tissue, or separation, disruption or retraction of a tissue that has ruptured. |
front 5 advantages of ultrasound > MRI | back 5 higher resolution, portable, lower cost, no known hazards, ability to palpate while imaging at time of exam. |
front 6 disadvantages of ultrasound | back 6 operator dependent, limited ability to show joint surfaces/intraarticular structures, can show cortical outline of bone but not beneath, does not cross air-tissue interfaces and obese patients are not imaged well with ultrasound. |
front 7 Canadian C-Spine Rule and the NEXUS | back 7 evidence-based guidelines that help clinicians decide whether radiographic examination is necessary based on specific clinical criteria |