Y khoa, dược - X - Rays and diagnostic radiology

53X-rays and Diagnostic Radiology53-2Learning Outcomes53.1 Explain how x-rays are used for diagnostic and therapeutic purposes.53.2 Compare invasive and noninvasive diagnostic procedures.53.3 Carry out the medical assistant’s role in x-ray and diagnostic radiology testing.53-3Learning Outcomes (cont.)53.4 Demonstrate the medical assistant’s duties when preparing a patient for an x-ray.53.5 Explain the risks and safety precautions associated with radiology work.53.6 Describe proper procedures for filing and maintaining x-ray films and records.53-4IntroductionDiagnostic radiology is a valuable tool Screening Clinical diagnosisMedical assistantRole in noninvasive and invasive proceduresSafety issuesProper handling and storage of filmsPreparation and instruction of patients53-5Brief History of the X-Ray Discovered in 1895 by Wilhelm Konrad RoentgenElectromagnetic waveTravels 186,000 miles/secShort wavelengthPenetrates solid objectsReacts with photographic film53-6Brief History of the X-Ray (cont.)Diagnostic and therapeutic usesRadiologist Physician Interprets filmsRadiologic technologists53-7Diagnostic RadiologyContrast mediumPurposeMakes internal organs denserBlocks passage of x-rays to filmProvides a clearer image of organs and tissuesTypesGasesHeavy metal saltsIodine compounds53-8Diagnostic Radiology (cont.)Invasive proceduresA catheter, wire, or other testing device is inserted into a blood vessel or organ by a radiologistRequires surgical aseptic techniquesPatients must be closely monitored, especially if anesthesia is used53-9Diagnostic Radiology (cont.)Noninvasive proceduresView internal structuresStandard x-raysUltrasonography Do not require inserting devices, breaking the skin, or as great a degree of monitoring as invasive proceduresUses the conventional x-ray machine or specialized instruments53-10Apply Your KnowledgeWhat is the difference in noninvasive and invasive procedures?ANSWER: Noninvasive procedures do not require inserting devices, breaking the skin, or special monitoring and use conventional x-ray machines or specialized instruments to visualize internal organs. Invasive procedures require surgical aseptic technique for the insertion of a catheter, wire, or other testing device into an organ or blood vessel.X-rays are __________________ waves that travel at the speed of light and penetrate solid objectselectromagneticRight!53-11Medical Assistant’s Role in Diagnostic RadiologyAssist with or perform proceduresBased on scope of practice for statePre- and postprocedure patient carePatient education53-12Medical Assistant’s Role in Diagnostic Radiology (cont.)Preprocedure careSchedule appointmentsProvide preparation instructionsExplain the procedure Ask pertinent questionsMedication historyWomen – possibility of pregnancy 53-13Medical Assistant’s Role in Diagnostic Radiology (cont.)Care during and after a procedureAssist with placing, removing, and developing filmTasks listed in Procedure 53-1 “Assisting with an X-ray Examination”53-14Apply Your KnowledgeHow can you find out what role you can take in radiologic testing as a medical assistant?ANSWER: Check with your state’s scope of practice for medical assistants.Very Good!53-15Common Diagnostic Radiologic TestsContrast media in diagnostic tests Adverse effectsMild to severeLocalized to systemicCheck for allergy to fishExamples AngiographyArthrographyBarium swallow or enemaCystographyMyelographyRetrograde pyelographyNuclear medicine studies53-16Common Diagnostic Radiologic Tests (cont.)Fluoroscopy X-rays cause certain chemicals to emit visible lightAllows for viewing movement of an organ or passage of substances through organsHysterosalpingographyExamination of uterus and fallopian tubes by fluoroscopyUsed to evaluate shape and structure of uterus and patency of fallopian tubes53-17Common Diagnostic Radiologic Tests (cont.)Arthrography Contrast medium and fluoroscopy Used to diagnose abnormalities or injuries in cartilage, tendons, or ligamentsBarium enema or swallowContrast medium – bariumDiagnose and evaluate obstructions, ulcers, polyps, diverticulosis, tumors, or motility Patient instructions and compliance important53-18Common Diagnostic Radiologic Tests (cont.)Cholecystography – detect gallstones or abnormalities of the gallbladderCholangiography – evaluate function of bile ductConventional tomography Uses a computerized camera that moves back and forth over the patientOne view per arc over patientComputer tomography Camera rotates completely around the patient Cross-sectional view from each rotation53-19Common Diagnostic Radiologic Tests (cont.)Heart x-ray – shows configuration of the heart and cardiac enlargement or aortic dilationIntravenous pyelography (IVP) Used to evaluate urinary systemShows contrast medium moving through kidneys, ureters, and bladderRetrograde pyelography – Similar to IVP but contrast medium injected through a urethral catheter53-20Common Diagnostic Radiologic Tests (cont.)Kidneys, ureters, and bladder (KUB) radiography X-ray of abdomenAssesses the size, shape, and position of urinary organsMagnetic resonance imaging (MRI) – uses strong magnetic field to examine internal structures and soft tissuesMammography – x-ray exam of internal breast tissues53-21Common Diagnostic Radiologic Tests (cont.)Myelography Fluoroscopy of the spinal cord used to evaluate spinal abnormalitiesPerformed less frequently because of new technologyNuclear medicine Use of radionuclides or radioisotopes to evaluate internal organsTypes includeSPECTPETMUGA53-22Common Diagnostic Radiologic Tests (cont.)Stereoscopy – specially designed microscope used to produce 3-D images of abnormalities in the skullThermographyInfrared camera photographs variations in skin temperatures Diagnosis of breast tumors, breast abscesses, and fibrocystic breast disease53-23Common Diagnostic Radiologic Tests (cont.)Ultrasound Directs high-frequency sound waves to produce an echo of the internal organProduces image based on echo XeroradiographyX-rays developed with powdered toner on specialized paperLess radiation exposure 53-24Apply Your KnowledgeTrue or False:___ Fluoroscopy is used for many procedures. ___ Hysterosalpingography is used to evaluate the patency of the colon.___ Cholangiography is used to detect abnormalities of the gallbladder.___ For an IVP, the radiologist injects the contrast medium through a catheter.___ An MRI uses a combination of nonionizing radiation and a strong magnetic field.___ Myelography is done frequently to evaluate for spinal abnormalities.___ Thermography uses an infrared camera to record variations in skin temperature.ANSWER:less often due to advanced technologiesFFFFTTTa retrograde pyelographybile ductfallopian tubesBravo!53-25Common Therapeutic Uses of RadiationRadiation therapy – used to treat cancer by preventing cellular reproductionTwo types:Teletherapy – allows deep penetration; used for deep tumorsBrachytherapy Places temporary radioactive implants close to or directly into the cancerous tissueRequires special precautions for radiation safety53-26Radiation Safety and DoseReducing patient exposureAdvances in technologyAssessment of benefit-to-risk ratio NCRP Guidelines for protection from radiationPrevent serious damage from radiation by limiting radiation dose levelsReduce risk of cancer and genetic effectsIndividual dose limits set53-27Radiation Safety and Dose (cont.)Personnel safetyAlways wear a radiation exposure badgeMake sure equipment is working properlyAnyone present when equipment is operating should wear lead shield53-28Apply Your KnowledgeWhat are the two types of radiation therapy?ANSWER: Teletherapy allows for deep penetration and is used for deep tumors. Brachytherapy involves the implantation of temporary radioactive implants close to or directly into cancerous tissue.What should the physician consider before ordering radiologic testing for a patient?ANSWER: The benefit-to-risk ratio.Super!53-29Storing and Filing X-raysKeep fresh film on hand Maintain new and exposed film in good condition at proper temperature and humidityPrevent pressure marks Keep expiration dates visibleUse oldest film firstOpen all packages or boxes in darkroomDo not store near acid or ammonia vapors53-30Storing and Filing X-rays (cont.)Document x-ray informationPatient record card or record bookVerify that film is labeled correctlyFile correctlyFilm-filing envelopeUse “out-card” when removing file53-31Electronic MedicineTelemedicine technologyRapid videoComputer-based communicationsStereotaxis – magnetic neurosurgery techniqueDigital imaging Eliminates traditional x-ray filmsDecreased exposure to radiationDICOM – communication protocolAdvances in radiology3D/4D ultrasound“live-action” images53-32Apply Your KnowledgeHow do you store new and exposed x-ray film?ANSWER: X-ray film should be stored at proper temperature and humidity. Packages should be stored on end and not stacked.What is DICOM?ANSWER: DICOM is a communications protocol for handling, storing, printing, and transmitting information in medical imaging.Fantastic!53-33In Summary53.1 An x-ray is a high-energy electromagnetic wave that travels at the speed of light and can penetrate solid objects. X-rays can be used for diagnosis by producing images of internal body structures. Therapeutically, x-rays are used to treat cancer by preventing cellular reproduction. 53.2 Invasive procedures require a radiologist to insert a catheter, wire, or other testing device into a patient’s blood vessel or organ through the skin or a body orifice. Noninvasive diagnostic procedures do not require inserting devices, breaking the skin, or the degree of monitoring needed with invasive procedures.53-34In Summary (cont.)53.3 A medical assistant can work directly with a radiology facility to assist the radiologist or technicians in performing diagnostic procedures. Providing preprocedure and postprocedure care are duties a medical assistant can perform in a medical or radiology facility. 53.4 The medical assistant can prepare the patient for radiological testing by thoroughly explaining preprocedure care and care during and after the procedure.53-35In Summary (cont.)53.5 The greatest risk associated with a radiology facility is the potential for radiation exposure to patients and health-care workers. To eliminate this risk, certain safety precautions should be followed. These include careful evaluation by the physician to determine the medical necessity of radiology testing, avoiding x-rays altogether if a patient is pregnant, and requiring all personnel who work in a radiology facility to wear a dosimeter. 53-36In Summary (cont.)53.6 Proper procedures for filing and maintaining x-ray films and records include documenting the patient’s name, the date, the type of x-ray, and the number of x-rays taken in the patient record card or in the record book; properly labeling the film with the referring doctor’s name, the date, and the patient’s name; placing the processed film in a film-filing envelope; and filing the envelope according to office policy.53-37End of Chapter 53Words can be like X-rays if you use them properly--they'll go through anything. You read and you're pierced.” ~ Aldous Huxley