NTA Level 4 Semester Two

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER TWO Quality Control and Care of Ultrasound Equipment CRT04210 · Ultrasound Imaging START READING NOTES Study Quality Control and Care of Ultrasound Equipment using the sections below. Use the topic navigation to continue through Ultrasound Imaging. Contents of This Topic QUALITY CONTROL AND CARE OF EQUIPMENT THE COMPETENCE OF THE OPERATOR QUALITY ASSURANCE SERVICE TO THE PATIENT QUALITY OF IMAGE PRODUCTION PERFORMANCE TESTING TISSUE EQUIVALENT PHANTOMS TEST PHANTOMS Maintenance and care of equipment QUALITY CONTROL AND CARE OF EQUIPMENT Getting the best from your machine THE COMPETENCE OF THE OPERATOR Because of the difficulty of interpreting ultrasound images, ultrasound examinations should only be performed by trained and competent personnel. It is better not to do an examination at all than to provide incorrect or misleading diagnostic information. Operators should not only be trained according to acceptable international standards, but they should continue to improve their knowledge and skills throughout their working life. People in training should be supervised by trained and experienced personnel. QUALITY ASSURANCE Quality assurance (QA) is the process of ensuring that all aspects of an ultrasound service meet accepted international standards. A quality assurance program should consider: The competence of the operator The quality of service to the patient The quality of the image production The maintenance and care of equipment SERVICE TO THE PATIENT Patient care should consider the following matters: Careful appointment system to guarantee correct patient preparation, and minimal inconvenience. Careful consideration of patient safety, privacy and confidentiality. A well organized system of reporting procedures, including storage and delivery of results. Patient consent should always be obtained for invasive ultrasound procedures QUALITY OF IMAGE PRODUCTION Performance testing of ultrasound equipment is controversial for the following reasons: Ultrasound is considered a safe modality Modern ultrasound machines are considered stable and reliable Ultrasound QA testing is often considered to be rather subjective There are presently no regulations requiring a QA program PERFORMANCE TESTING Although testing of equipment is not essential, there are some applications, such as breast ultrasound, where it is very advisable. There are also some situations, where trained personnel are available to perform the task, and for those situations, there is special testing equipment available. TISSUE EQUIVALENT PHANTOMS The accuracy with which the ultrasound image represents an anatomical area depends on the correct functioning of the many components of the ultrasound machine. Occasional testing can ensure the machine is performing according to acceptable standards, and is accurate and consistent. Special test phantoms are available which enable people to make these checks TEST PHANTOMS Test phantoms are made of materials which are similar to tissue in their acoustic characteristics. They contain various targets and structures designed for testing a number of parameters such as image resolution and measurement accuracy. TEST PHANTOMS Maintenance and care of equipment Great care must be taken to keep an ultrasound machine in good working order and safe from hazards. 1/ The transducer If piezo electric elements are heated they lose their piezo electric properties because they become depolarized. Therefore the transducer should never be heat sterilized. They are also sensitive to mechanical shock and should never be dropped. MAINTENANCE AND CARE OF EQUIPMENT After use, always leave the transducer clean and dry. Wipe it with warm soapy water and dry. Never used oil based coupling gels. They will perish the rubber casing covering the transducer and allow oil to enter the inside which will cause damage. Use good quality, aqueous based gels only. The transducer should occasionally be sterilized by wiping with aqueous chlorhexidine solution or similar. Don’t leave the transducer to soak. MAINTENANCE AND CARE OF EQUIPMENT 2/ The control desk Remove any dirt or coupling gel by wiping with a soft cloth dampened with warm soapy water. NEVER sit liquids, such as cups of coffee on the control desk, or use the surface to hold other items. 3/ The main console Use the ultrasound machine in a cool dust free environment. Keep the air vents on the side of the machine clear of obstruction and clean. Clean any air filters present. Operate the machine with a voltage stabilizer to protect it from damage by voltage surges. MAINTENANCE AND CARE OF EQUIPMENT 4/ Electrical safety Inspect the transducer closely for any cracks or damage to the plastic housing. Inspect cables for any wear or damage to the insulation. Inspect any plugs, adapters or connector assemblies for any electrical dangers. Connect the machine directly to mains power and not to a multi outlet power board. ← PREVIOUS TOPICNEXT TOPIC →VIEW ALL MODULE NOTESVIEW SEMESTER NOTESVIEW ALL LEVEL NOTESALL DIAGNOSTIC RADIOLOGY NOTES Need These Notes as PDF? Need a clean, well-formatted PDF copy for offline study, revision or printing? Request the complete notes directly through WhatsApp. GET WELL-FORMATTED PDF NOTES

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER TWO Ultrasound Safety and Biological Effects CRT04210 · Ultrasound Imaging START READING NOTES Study Ultrasound Safety and Biological Effects using the sections below. Use the topic navigation to continue through Ultrasound Imaging. Contents of This Topic ULTRASOUND SAFETY IS ULTRASOUND SAFE? OPERATING MODES AND THEIR RISKS PULSED DOPPLER AND POWER DOPPLER BIOLOGICAL EFFECTS SAFE USE SOME GUIDELINES CONCLUSION ULTRASOUND SAFETY ULTRASOUND SAFETY BASIC RULES AND PRINCIPLES IS ULTRASOUND SAFE? So far ultrasound has not been proven to be unsafe in humans. However, ultrasound is now being very widely used and advances in technology are leading to increasing power levels being used to obtain diagnostic information. This can lead to measurable biological effects The interaction of ultrasound with biological tissue can result in effects which may cause heating, interfere with normal functioning of cells, and cause structural damage. It is important for people using ultrasound to do all they can to minimize the exposure of the patient to ultrasound to reduce these risks. OPERATING MODES AND THEIR RISKS B Mode ultrasound imaging records returning echoes strength as a brightness display on the screen. This is the normal grey scale imaging used for real time ultrasound. This uses the lowest output power and intensities and is generally considered safe in all applications, PULSED DOPPLER AND POWER DOPPLER Pulsed Doppler uses higher intensity of ultrasound than B Mode, and is therefore more likely to cause biological effects, particularly from heating. Pulsed Doppler ultrasound focuses the beam in a small area for longer periods increasing the dose to those tissues. Power Doppler also uses intensities higher than B Mode, but less than pulsed Doppler BIOLOGICAL EFFECTS There are two important effects which can be caused by ultrasound: 1/ Thermal (heating) 2/ Non thermal effects (cavitation) 1/ As the ultrasound beam travels through the tissue some of its energy is lost through absorption. This absorbed energy is converted into heat which causes a temperature rise of the tissues. The heat rise will depend upon: * the attenuation coefficient of the tissue * the operating frequency of the transducer * power/ intensity of the ultrasound beam * the length of operating exposure time BIOLOGICAL EFFECTS 2/ Non thermal effects ( cavitation ) The oscillating pressure wave caused by an ultrasound beam creates areas of compression and rarefaction. This can cause small bubbles to form in tissues. These can grow, oscillate in size, an at high intensity and pressure these can collapse. This causes high pressures and temperatures in the localized area with the potential to cause biological damage. While this risk is very small in general ultrasound, it is wise to be careful in early pregnancy where the tissues are more vulnerable. CAVITATION SAFE USE Changes in power output and increased use of Doppler ultrasound have led to awareness of the need to take every measure to ensure safe practice. The accepted guideline for safe use is known as the ALARA principle ( “As Low As Reasonably Achievable” ) This is a guide to minimizing exposure times and exposure intensity. ALARA SOME GUIDELINES 1/ Examinations should use B mode real-time in the first instance and employ color and spectral Doppler only when and if required. 2/ The overall examination should be kept as short as possible to minimize exposure times. 3/ The transducer should not be held in a fixed position any longer than necessary. 4/ The transducer should never be left resting on the patients body when not in use. 5/ The output power setting should be as low as possible consistent with obtaining a satisfactory image. 6/ Ultrasound examinations should only be performed for a specific medical indication to obtain useful diagnostic information. 7/ Only suitably trained people should be allowed to operate ultrasound machines. CONCLUSION Although harmful effects have not been shown to result from the use of ultrasound at normal diagnostic levels, the potential for harm does exist. More research still needs to be done. For example, we do not know if the effects from ultrasound exposure are cumulative. As in the use of x-rays, a very small risk is justified when the risk is minimal and the benefit high. ← PREVIOUS TOPICNEXT TOPIC →VIEW ALL MODULE NOTESVIEW SEMESTER NOTESVIEW ALL LEVEL NOTESALL DIAGNOSTIC RADIOLOGY NOTES Need These Notes as PDF? Need a clean, well-formatted PDF copy for offline study, revision or printing? Request the complete notes directly through WhatsApp. GET WELL-FORMATTED PDF NOTES

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 CRT04210 Ultrasound Imaging Notes Browse 22 study topics in Ultrasound Imaging, NTA Level 4, Semester 2. Formation of the Ultrasound Beam Ultrasound Transducers and Scanning Modes Ultrasound Artifacts Ultrasound Safety and Biological Effects Quality Control and Care of Ultrasound Equipment Biological Effects of Diagnostic Ultrasound Common Gynecological Anomalies – Part 1 Common Gynecological Anomalies – Part 2 Gynecology Uss Image characteristics and Optimization Interaction of Ultrasound With Matter Molar Pregnancy Renal Sonography Sonographic Sonographic Terminology Sonography In Hiv Sonography of the Gallbladder Ultrasound Artifact Ultrasound Beam Shape Ultrasound Of The Gallbladder Ultrasound of the Ovary and Endometrium Ultrasound Physics ← PREVIOUS MODULENEXT MODULE →SEMESTER NOTESNTA LEVEL 4 NOTESALL NOTES Need These Notes as PDF? Need a clean, well-formatted PDF copy for offline study, revision or printing? Request the complete notes directly through WhatsApp. GET WELL-FORMATTED PDF NOTES