Medical Imaging Examinations PDF

HSMI 1211 Introduction to Medical Imaging Medical Imaging Examinations MEDICAL IMAGING EXAMINATION PRE-REQUISITES MEDICAL IMAGING EXAMINATION List and understand the components of “technique” as applied to medical imaging. Define and differenti...

HSMI 1211 Introduction to Medical Imaging Medical Imaging Examinations MEDICAL IMAGING EXAMINATION PRE-REQUISITES MEDICAL IMAGING EXAMINATION List and understand the components of “technique” as applied to medical imaging. Define and differentiate between the different classifications of radiological examinations normally performed. Discuss the types of contrast media as well as the role of contrast media. List and discuss basic related terminologies. Define and explain the term ‘projection’ applicable in medical imaging. RADIOGRAPHIC TECHNIQUE Radiographic Technique SEQUENCE OF RADIOGRAPHIC Describes how a radiological examination is conducted to TECHNIQUE achieve a successful IDENTIFICATION OF PATIENT examination. PREPARATION OF PATIENT POSITIONING OF PATIENT It has a specific sequence that commonly practiced in various IMAGING TECHNICALITIES CONSIDERATION types of radiological examinations. RADIOLOGICAL EXAMINATION RISK MONITORING APPRECIATION OF IMAGE AND QUALITY Radiographic Technique SEQUENCE OF RADIOGRAPHIC TECHNIQUE A request for a particular radiological examination on a patient based on sound medical judgment. IDENTIFICATION THROUGH REQUEST FORM OF PATIENT Written form or through networking. Patient identity. Medical history. Intended radiological examination. Radiographer: to do proper identification, for procedure planning, modification and patient care. Radiographic Technique SEQUENCE OF RADIOGRAPHIC TECHNIQUE The necessary steps to be taken by the PREPARATION OF PATIENT patient before the examination To ensure a successful examination Depend on the type of examination and imaging modalities Examples: Fasting Physical activity Medication; premedication/abstention from medication Bowel preparation Empty bladder Contrast media preparation Sterile preparation Psychological preparation Radiographic Technique SEQUENCE OF RADIOGRAPHIC TECHNIQUE The orientation of the patient in relation to the imaging set-up. POSITIONING OF PATIENT Needed to display the anatomy Based on the imaging modality Examples: MRI: mostly only supine position Erect Recumbent (Patient horizontal): Supine, Prone Trendelenburg position Body is laid supine (flat on the back) Feet higher than the head by 15° - 30° Right Posterior Oblique Right Anterior Oblique Right / Left lateral (either in erect or recumbent Radiographic Technique SEQUENCE OF RADIOGRAPHIC TECHNIQUE POSITIONING OF PATIENT Radiographic Technique SEQUENCE OF RADIOGRAPHIC TECHNIQUE IMAGING TECHNICALITIES CONSIDERATION Differ between modalities. Imaging Parameters: Refers to any parameters that when changed or manipulated will result in changes to: Image quality Safety Economics Examination time Examples: General x-ray: kV, mAs, etc. MRI: TE, TR, Flip angle etc. Ultrasound: frequency, gain Radiographic Technique SEQUENCE OF RADIOGRAPHIC TECHNIQUE RADIOLOGICAL EXAMINATION RISK Radiation MONITORING Contrast media MRI Ultrasound It is the professional obligation of the Cross-infection radiographer NOT to cause any extra Any risks associated with harm to the patient. patient’s manipulation. Radiographic Technique SEQUENCE OF RADIOGRAPHIC TECHNIQUE The resultant image should have all the information that will enable clinician to APPRECIATION OF IMAGE decide on patient’s management. AND QUALITY Common standard for image appreciation ,IQC: Image Quality Criteria (IQC) Outlines the minimum requirements for each image for it to be acceptable for diagnosis. The terms “density”, “contrast”, “resolution” and “distortion” are among the terminologies commonly associated with image quality in images acquired from certain imaging modalities. CLASSIFICATION OF RADIOLOGICAL EXAMINATION Classification of Radiological Examination CLASSIFICATION OF RADIOLOGICAL EXAMINATION Ionising Non-Ionising Radiation Radiation Projection Radionuclide CT Scanning MRI Ultrasound Radiography Imaging Plain Specialised NO contrast WITH contrast media media Classification of Radiological Examination NO contrast WITH contrast Plain Specialised media media - Can demonstrate functional status CONTRAST MEDIA  Positive Contrast Media – For Projection Radiography only – Made up of elements that are substantially of higher atomic number compared to the body tissues (where it is supposed to be present). How it works: The contrast media absorb radiation more readily than other materials of lower atomic number. The presence of positive contrast media in a particular tissue will increase the attenuation properties of the tissue. Hence this situation leads to more absorption of radiation (photoelectric process). This makes the structures with the contrast medium look brighter on the radiographic image.  Positive Contrast Media – For Projection Radiography only – The most common positive contrast media are: Non-iodinated Iodinated The non-iodinated contrast medium is usually a barium sulphate solution, used primarily for radiological studies involving the alimentary tract. Water soluble, oily, water-insoluble. Negative Contrast Media Consist of a radiolucent substance Lower atomic number or density than the surrounding structures Offer less attenuation Structures outlined using negative contrast media appear darker than surrounding soft tissues in the image. Examples of negative contrast media used in medical imaging include: Air in double contrast barium enema Carbon dioxide is used in CT Colonoscopy as it is more readily absorbed by the body; oil, fat and milk. Negative Contrast Media No. 4, 6 & 7 Air as a negative contrast media. Appear darker on the radiograph. Indications and Contra-indications Indication: Contraindication: Justification to use or perform a certain test, medication, Justification NOT to use or procedure, or surgery in perform a certain test, managing’s a patient’s medical medication, procedure, or condition. surgery in managing’s a “Concept of benefits against the risks” patient’s medical condition. Justification for examination: The reasons: Type of information Patient based Anatomical/Structural Physiological/Functional Equipment based Procedural based Contrast Media Introduced into the body to enhance the contrast of certain tissues, which might not be readily visible in a radiographic image. Function: Make changes to the attenuation properties of tissues with its administration and this will be shown in the image. Either increased or reduced depending on the type of contrast media used. Requires preparation of patient Informed consent for contrast media administration: to reduce the probability of the patient exhibiting sensitivity to contrast media. TERMINOLOGIES Anatomical Positions and Body Planes Body Habitus The Positioning of Patient: Terminologies Anatomical Body Planes Projections Movements Body Position Body Habitus Positions Anterior Sagittal Anteroposterior Abduction Erect Hypersthenic Posterior Coronal Posteroanterior Adduction Recumbent Sthenic Superior Transverse Tangential Flexion Prone Hyposthenic Inferior Axial Decubitus Extensions Supine Asthenic Lateral Longitudinal Lateral Inversion Fowler’s Medial Horizontal Eversion Tredelenburg Proximal Pronation Sim’s Distal Supination Cephalad Caudad Dorsal Superficial Deep PROJECTIONS Radiographic Projection/Position Radiographic Projections Radiographic Positions Anteroposterior Posteroanterior Left Posterior Oblique Right Posterior Oblique Right Lateral Left Lateral Left Anterior Oblique Right Anterior Oblique RADIOLOGICAL EXAMINATIONS  MEDICAL IMAGING EXAMINATION Identify and list the common classification of pathologies and diseases that requires imaging. Identify explain the specific radiological examination technique for some of the imaging related pathologies and disease. Discuss some of patient preparation and patient post-procedural in radiological examination. Discuss overall radiographer’s role in relation to radiological examination. PATHOLOGIES AND DISEASES -common pathologies and diseases that require radiological examination Indications: Common pathologies Infections (bronchitis, nephritis) Calcifications – as in renal calculi, Trauma (fractures, dislocations, joint biliary calculi etc. effusions, fat pads) Degenerative diseases – Tumour lesions- malignant or (rheumatoid arthritis, benign osteoarthritis, etc) Foreign bodies – inhaled or Metabolic disease and infections otherwise (osteochondritis dissecans, Pain of unknown origin osteochondrosis, osteomalacia, Perforation (especially in chest and osteomyelitis, etc.) abdomen) Functional disorder/disease Obstruction (abdomen) specific to region of interest e.g In cases of suspected internal cardiovascular disease bleeding Congenital conditions. Indications for plain x-rays: Examples Chest x-ray: Abdominal x-ray Chest pain Perforation: free gas under diaphragm Respiratory disorder: asthma, apnoea, Non-specific abdominal pain emphysema. Bowel obstruction Repeated or persistent chest infection- Ulcero-inflammatory disease by viruses, bacteria, fungi, protozoa, (cholecystitis, pancreatitis, appendicitis and micro-organisms: bronchitis, etc.) bronchiectasis, pneumonia, Abscess tuberculosis Tumours Cardiovascular diseases Gastro-intestinal bleeding Chest trauma Foreign bodies Tumour lesion – malignant or benign Abdominal trauma Abdominal calcifications: renal calculi Inhalation of foreign bodies etc. RADIOLOGICAL EXAMINATION -specific to certain pathology and disease Projection Radiography Consists of the use of: X-ray tube to deliver the radiation to the patient An image receptor to record the image. The image depicts a two-dimensional image of a three-dimensional object. Can either be static images or dynamic images. Specialised Radiography The use of contrast media. To enable visualization of anatomical structures as well as the functional status of structures. The use of specific technique. In the form of modification of body position or timing of the image sequence. E.g.: Intravenous urography (IVU) involves specific timing sequence for image acquisition. The use of specific equipment or accessories. Fluoroscopic / Angiographic equipment Contrast enhanced study Projection Radiography: Plain and Specialised Plain Specialised Examinations performed on ROI in Procedures that make use of the body without the use of contrast media and maybe some contrast media. special imaging modalities. To study anatomy as well as Depict the anatomy but not the physiology of body systems to functional status of the ROI. diagnose pathophysiological Does not require elaborate conditions. preparation of the patient. May require some specific Less occurrence of complications. preparation of patient before the examination. May be associated with post procedural patient education. Can be accompanied by some complications. Interventional Radiology (IR) The procedure that is “invasive” or “surgical” in nature but does not need the use of general anesthesia. Invasive – procedure that involve penetration into the body either by puncture, perforation, incision, or catheterization using dedicated equipments such as needles or catheters. These procedures make use of imaging modalities. The procedures are not just to image the patient’s body but to also perform the treatment on the conditions of patients. Similar to specialized imaging procedure but usually performed under “sterile technique”. Sterile environment: environment that is free from pathogens. Sterile technique: the technique used to achieve or maintain sterility Specialised Radiography - Equipment Specific procedural tray Branula Needles Catheters Emergency trolley/cart Ambubag Endotracheal tubes Laryngoscope Specialised Radiography/IR Examples Body System Examination Definition Respiratory Bronchography Contrast enhanced examination of the lower respiratory tract, with particular emphasis on the bronchial tree. Lung Biopsy - Surgical removal of a tissue sample for patho- Interventional histological analysis Skeletal system Arthrography Radiographic examination of the synovial joint space with the introduction of contrast media (positive and/or negative) Myelography Radiographic examination of the central nervous system structures within the spinal canal with the direct instillation of the contrast media into the subarachnoid space. Discography Examination of the intervertebral disks through direct injection of contrast media into the discs. Specialised Radiography/IR Examples Body System Examination Definition Circulatory/ Angiography Radiographic examination of blood vessels with the Cardiovascular introduction of contrast media. system Angiocardiography Radiographic examination with the introduction of contrast media to study the heart chambers or pulmonary artery. Venography Radiographic examination of the venous system by the introduction of contrast media. Digestive system Barium swallow Contrast-enhanced study of the oesophagus. Barium meal Contrast-enhanced study of the stomach and proximal bowel. Barium follow thru Contrast-enhanced study of the small bowel. Barium enema Contrast-enhanced study of the large colon. Specialised Radiography/IR Examples Body System Examination Definition Reproductive system Hysterosalpingography Contrast enhanced procedure to determine (HSG) structural and functional defects to the female reproductive system. Excretory/Urinary Intravenous urography Contrast enhanced radiological examination to system (IVU) demonstrate the urinary system. Cystography/Micturati Contrast enhanced study of the urinary bladder. ng cystourethrography May be accompanied by functional study involving (MCUG) micturating. Nephrostomography An invasive procedure involving percutaneous insertion of catheter into kidney. Retgrograde/Antegrad Contrast-enhanced study for the ureters involved e pyelography the insertion of a catheter from the urethra into the bladder and the ureters. Specialised Radiography/IR Examples Body System Examination Definition Biliary system Endoscopic Retrograde An invasive procedure involving the insertion of an Cholangiopancreatogr endoscope into the bile duct system and injecting aphy (ERCP) contrast media into the bile duct system. Operative Performed in OT to visualize the biliary tree after Cholangiography surgical intervention. A small catheter is placed intraductally through the cystic duct remnant and contrast medium injected. T-Tube Cholangiogram Contrast media studies of the biliary tree via a surgically placed catheter. Pecutaneous A procedure to demonstrate and evaluate the Transhepatic biliary system with a direct puncture of the biliary Cholangiogram ducts using a needle. Other Sinogram/Fistulogram To locate and demonstrate the extend of a sinus or fistula The team for specialized radiography / IR Radiologist / Clinician Radiographer Nurse Other support staff PATIENT-PREP AND POST- PROCEDURAL -in relation to radiological examination Patient Care Good communication skills are important. Constant reassurance throughout the procedure. Explanation of: Procedure Purpose of the obtaining consent (consent form) Aware of any potential harm (of any kind) to the patient. Certification in basic life support (First Aider). Understanding and limiting the risks concerning the various imaging procedures (modalities). ROLE OF RADIOGRAPHER -in relation to radiological examination Radiographers’ role Understand their role in providing imaging services with the best possible diagnostic quality at the lowest risks and lowest costs. Equipped themselves with necessary knowledge and skills to carry out patient’s imaging related procedures which may involve modification if the situation arise. Optimise the use of equipment and available resources in achieving optimum results. Aware of the risks and complication that may be associated with every radiological procedures Summary Understanding what are the pre-requisites of radiological examinations. Elements of technique outlined. Differentiation between various types of radiological examinations discussed.