radiology and diagnostic imaging زمان امتحان : اولین جلسه بعد از عید...

RADIOLOGY AND DIAGNOSTIC

IMAGING

RADIOLOGY AND DIAGNOSTIC

IMAGING

زمان امتحان : اولین جلسه بعد از عیدنوع امتحان: کتبی

نمره از نمره پایان ترم2نمره:

Elsevier items and derived items © 2008 by Saunders, an imprint of Elsevier Inc. 2

PRETESTPRETEST

True or False1. A radiologist is a medical doctor specializing in the

diagnosis and treatment of disease using radiant energy.

2. The permanent record of the picture produced on x-ray film is a sonogram.

3. The purpose of a contrast medium is to make a structure visible on a radiograph.

4. With an anteroposterior view, the x-rays are directed from the back towards the front of the body.

5. Mammography can be used to detect breast calcifications.


PRETEST, CONT.PRETEST, CONT.

True or False6. An upper GI examination assists in diagnosing

kidney stones.

7. An IVP is a radiograph of the kidneys and urinary tract.

8. Ultrasonography allows for continuous viewing of a structure.

9. Obstetric ultrasound can be used to determine gestational age.

10. A patient must remove all metal before having an MRI.


Content OutlineContent Outline

1. Wilhelm Konrad Roentgen

a. Discovered x-rays while working with a cathode ray tube (1895)

b. Noticed that rays could pass through solid materials (e.g., paper, wood, human skin)

c. Because he did not know what they were• Named them x-rays

• Renamed roentgen rays (better known as x-rays)

Introduction to Radiology


Introduction to Radiology, cont.


2. Characteristics of x-rays:

a. High-energy electromagnetic waves

b. Invisible

c. Short wavelength• Enables them to penetrate solid materials




3. Radiographic film:

a. Placed behind part being examined

b. Part of body is "photographed"

c. Shadow or image of internal body structure: produced on the film




4. Radiograph: the permanent record of a picture of an internal body organ or structure produced on radiographic film

5. Radiology: the branch of medicine that deals with the use of radiant energy to diagnose and treat disease

6. Radiologist: medical doctor who specializes in diagnosis and treatment of disease with radiant energy




7. X-rays used to:

a. Visualize internal organs and structures

b. Diagnose disease

c. Treat disease (e.g., malignant neoplasms)




8. Medical office: may have radiograph machine

a. More often: radiographs taken in hospital

9. Patient preparation for radiographs

a. May require no preparation (e.g., bone study)

b. May require a lot of preparation (e.g., lower GI)




10.MA responsible for:

a. Providing patient with preparation instructions

b. Making sure patient understands instructions

11.If patient does not prepare properly:

a. Poor quality radiograph

b. Rescheduling of procedure


Contrast MediaContrast Media

1. Differences in density between body structures: produce shadows on film

a. Examples:• Bone is dense and absorbs x-rays

– Appears white on film

• Lungs contain air and x-rays penetrate them

– Appears black on film


Contrast Media, cont. Contrast Media, cont.

2. Radiolucent: a structure that permits the passage of x-rays (lungs)

3. Radiopaque: a structure that obstructs the passage of x-rays (bone)


Lungs are RadiolucentLungs are Radiolucent

From Meschan I: Synopsis of radiologic anatomy with computed tomography, Philadelphia, 1980, Saunders.



4. Contrast medium: a substance used to make a structure visible on a radiograph

a. Used when densities of two adjacent organs or structures are similar

5. Consists of radiopaque chemicals:

a. Causes body tissue or organ to absorb more radiation

b. Tissue or organ: becomes visible and appears white on film



6. Qualities contrasts media must have:

a. Must be able to be Ingested or injected into body tissue or organs

b. Not cause harm to patient



7. Types of contrast media

a. Barium sulfate• Commonly used

• Chalky compound

• Cannot be penetrated by x-rays (radiopaque)

• Not absorbed into body by gastrointestinal (GI) tract

• Used to examine GI tract

– Does not alter normal function



b. Iodine compounds• Radiopaque contrast medium

• Used for examination of gallbladder and kidneys

• May produce allergic reaction

– Important to ask patient if allergic to iodine or foods containing iodine

– Patients with known allergies: given an iodine-sensitivity test

1) Precautionary measure to avoid an allergic reaction



c. Air and carbon dioxide• Cause structure to become less dense than

surrounding area

• Appears darker on film


What Would You Do?What Would You Not Do?



FluoroscopyFluoroscopy

1. Fluoroscope: an instrument used to view internal organs and structures directly on a screen

2. Fluoroscopy: examination of a patient with a fluoroscope

3. Radiopaque medium: often used to outline various parts of body

4. Patient positioned between radiographic tube and fluorescent screen


Fluoroscopy, cont. Fluoroscopy, cont.

5. X-rays pass through body

a. Radiologist views action of body organs on a screen• Examples:

– Stomach

– Intestines


Fluoroscopy, cont. Fluoroscopy, cont.

6. Radiographs taken while performing procedure

a. Permit a detailed study of structure

b. Provide a permanent record


Positioning the PatientPositioning the Patient

1. Position determined by:

a. Purpose of examination

b. Area to be examined

2. Usually positioned so several different views can be taken

a. Provides complete three-dimensional picture


Positioning the Patient, cont.Positioning the Patient, cont.

3. Jewelry must be removed: will obscure radiograph

4. Patients must not move during examination: to prevent blurring of image

a. Ensures good visualization of part being examined

b. Avoids having to retake radiograph


Positioning the Patient, cont. Positioning the Patient, cont.

5. Radiographic views

a. Anteroposterior view (AP)• X-rays directed from front to back of body

– Anterior aspect of body: faces radiograph tube

– Posterior aspect of body: faces film



b. Posteroanterior view (PA)• X-rays directed from back to front

– Posterior aspect of body: faces radiograph tube

– Anterior aspect of body: faces film


Posteroanterior View (PA)Posteroanterior View (PA)




c. Lateral view• X-ray beam passes from one side of body to

opposite side

d. Right lateral view (RL)• Right side of body: positioned next to film

• X-rays directed through body: from left to right side



e. Left lateral view (LL)• Left side of body positional next to film

• X-rays directed through body from right to left side

f. Oblique view• Body positioned at an angle



g. Supine position• Patient positioned on back

h. Prone position• Patient positioned on abdomen

– With head turned to side


Specific Radiographic Examinations

Specific Radiographic Examinations

1. MA should:

a. Understand purpose of commonly performed radiographic examinations

b. Be able to instruct patient in• Proper preparation for each examination


MammographyMammography

1. Radiographic examination of breasts2. Used to:

a. Detect breast disease• Benign breast masses

• Breast calcification

• Fibrocystic breast disease

• Breast cancer

b. Monitor effects of surgery and radiation treatment on breast tumors


Mammography, cont. Mammography, cont.

3. Uses low doses of x-rays4. Abnormal area: appears different from

normal breast tissue


MammogramMammogram

From Prue L: Atlas of mammographic positioning, Philadelphia, 1994, Saunders.



5. Tumor can be detected: when growth is less than 1 cm (size of a pea)a. Before it is able to be palpated

b. If malignant: can be removed at an early stage• Usually results in conservative treatment

– Less disfigurement

– Higher survival rate

6. Early diagnosis and treatment of breast cancer: survival rate as high as 94%



7. Patient preparation:

a. Do not wear lotions, powders, or deodorants • May contain small amounts of metal

– Shows up on radiograph

– Interferes with interpretation

b. Instruct patient to wear two-piece outfit• Patient must remove clothing from waist up



8. Procedure: usually performed by a radiologic technologist (rad tech)

a. Patient's breast positioned on machine

b. Pressure applied with plastic compression paddle • Purpose of breast compression

– To obtain a clear radiograph

– To lower radiation dosage



c. During procedure• Patient must hold breath and remain still

momentarily

– Movement can blur image (may require a repeat radiograph)


MammographyMammography

From Ballinger PW, Frank ED, eds: Merrill’s atlas of radiographic positions and radiologic procedures, vol 2, ed 10, St. Louis, 2003, Mosby.



d. Two radiographs taken of each breast• One from above

• One from side

e. Radiologist checks mammogram• Occasionally orders additional images: to

obtain more complete view



9. Radiologist studies mammogram for:

a. Breast cancer

b. Breast problems

10.Written report of findings: sent to patient's physician


Upper GIUpper GI

1. Upper Gastrointestinal (Upper GI)

a. Examination of upper digestive tract using:• Fluoroscopy

• Radiography


Upper GI, cont. Upper GI, cont.

b. Used to diagnose disorders of:• Esophagus

• Stomach

• Duodenum

• Small intestines



c. Examples of disorders: • Peptic ulcers

– Benign tumors

– Malignant tumors

d. Patient preparation: stomach must be empty• Food obscures image



e. To prepare:• Light meal: evening before examination

• Nothing by mouth (NPO), including water and medications, after midnight

– Food/fluid: cause confusing shadows on radiograph



f. Contrast medium used: barium mixed with water and flavoring• Known as barium swallow

• Chalky taste



g. Procedure• Patient swallows barium

• Using fluoroscopy: radiologist observes passage of barium

– Down esophagus

– Into stomach and duodenum

• Radiographs taken periodically

• Patient's position changed at various times

– To obtain different views of upper GI tract



h. Radiologist may want to observe• Passage of barium through small and large

intestines

– Patient must wait at facility

– Return several times for more radiographs



i. Explain to patient• Barium appears in stool the next day

– Causes stool to be lighter in color

• May cause constipation: need for a laxative

– To prevent: drink water following procedure


Lower GI Lower GI

2. Lower Gastrointestinal

a. Examination of lower digestive tract using:• Fluoroscopy

• Radiography

b. Used to observe and obtain: permanent pictures of colon

c. Colon filled with barium• Using a tube inserted into colon


Lower GILower GI



Lower GI, cont. Lower GI, cont.

d. Used to diagnose disorders of lower intestines:• Polyps

• Tumors

• Lesions

• Diverticulosis



e. Colon must be thoroughly cleansed in advance• To remove gas and fecal material

– Gas: shows up as confusing shadows

– Fecal material: obscures image of colon



f. Patient preparation• The day before the examination:

– Consume only clear liquids

1) Water, coffee, tea, clear broth

– Take a laxative

– An enema may also be required



• NPO except water after midnight

• Morning of examination:

– Warm-water cleansing enema: until returns are clear



g. Procedure• Patient lies on one side

– Barium inserted into colon through a tube

– Patient will have sensation of fullness and urge to defecate

• As barium enters colon

– Radiologist watches on fluoroscopic screen



• Radiographs taken periodically

• Patient moved in various positions

– To allow barium to fill colon completely

– Obtain better visualization of colon

• Patient allowed to evacuate barium

– Another radiograph is taken


Intravenous Pyelography Intravenous Pyelography

1. Radiograph of:

a. Kidneys

b. Urinary tract


Intravenous Pyelogram (IVP)Intravenous Pyelogram (IVP)



Intravenous Pyelography, cont.


2. Used to diagnose:

a. Kidney stones

b. Blockage/narrowing of urinary tract

c. Growths within or near urinary system




3. Patient preparation

a. Light evening meal

b. NPO after 9:00 PM

c. Laxative and cleansing enemas• To remove gas and fecal material

– Permits better visualization of urinary tract




4. Contrast medium

a. Iodine administered IV

b. As iodine enters bloodstream• Patient may feel warm and flushed

• Have metallic or salty taste in mouth

– Normal reaction: lasts a few minutes

c. If patient allergic to iodine: different type of contrast medium used


Other Types of RadiographsOther Types of Radiographs

1. Angiocardiogram

a. Radiograph of heart

b. Valves and vessels examined using:• Radiography

• Fluoroscopy

c. Radiopaque contrast medium


Other Types of Radiographs, cont.


2. Bronchogram

a. Radiograph of lungs

b. Radiopaque contrast medium used

3. Cerebral angiogram

a. Radiograph of major arteries of brain





4. Cholangiogram

a. Radiograph of bile ducts


5. Coronary angiogram

a. Radiograph of coronary arteries





6. Cystogram

a. Radiograph of urinary bladder


7. Hysterosalpingogram

a. Radiograph of uterus and fallopian tubes





8. Retrograde pyelogram

a. Radiograph of kidneys and urinary tract

b. Radiopaque contrast medium used• Injected directly into ureters

– Flows to kidney through ureters


Introduction to Diagnostic Imaging

Introduction to Diagnostic Imaging

1. Visualization of internal body structures in great detail

2. Performed in hospital

a. MA may need to relay to patient:• What to expect during procedure

• Any patient preparation


UltrasonographyUltrasonography

1. Also called ultrasound (US)2. Oldest of diagnostic imaging

procedures3. Uses high-frequency sound waves to

study soft tissue structure


Ultrasonography, cont. Ultrasonography, cont.


a. Conditions of abdominal and pelvic organs• Liver

• Gallbladder

• Spleen



• Pancreas

• Kidney

• Uterus and ovaries


Ultrasound of KidneyUltrasound of Kidney

From Tempkin BB: Ultrasound scanning: principles and protocols, ed 2, Philadelphia, 1999, Saunders.



5. Echocardiogram: ultrasound examination of the heart

a. Determines size, shape, position of heart

b. Movement of heart valves and chambers



6. Advantages of US

a. Shows movement

b. Allows for continuous viewing of a structure

c. Uses sound waves rather than radiation



7. Limitations of US

a. Sound waves: cannot penetrate through bone or gas-filled cavities (lungs)• Cannot be used to evaluate these structures

b. May be difficult with obese patients• Adipose tissue: interferes with sound wave

transmission



8. Procedure

a. Probe containing transducer placed firmly on patient's skin• Transducer produces sound waves

b. Probe moved over body area to be examined• Sound waves directed into tissues



c. Sound waves reflected back to transducer (similar to echocardiography)

d. Image displayed on viewing screen: oscilloscope

e. Images recorded on film and videotape: sonogram• Patient often permitted to view screen during

procedure



9. Obstetric ultrasound used to:

a. Determine gestational age of fetus

b. Confirm due date

c. Detect congenital abnormalities

d. Detect ectopic pregnancy

e. Detect multiple pregnancies

f. Determine baby's position and size late in pregnancy



10.Patient Preparation for US

a. Safe and painless

b. Takes 15 to 45 minutes to complete• Depends on part being examined



c. Preparation: based on part of body examined• US of gallbladder and liver: fast for 8 to 12

hours

• Obstetric US: patient must consume 32 oz of fluid

– 1 hour before procedure



d. During procedure:• Patient must remain still

– Movement interferes with accurate results

• May need to change positions

– To view organs at different angles


Computed TomographyComputed Tomography

1. Also known as CT or CAT scan2. Advanced radiographic examination3. Uses minimal amount of radiation4. Produces a series of cross-sectional

images of a body part


Computed Tomography, cont. Computed Tomography, cont.

5. Permits imaging of structures that cannot be visualized with x-ray studies

6. Can view bones and organs of head and body in fine detail

a. Very good for diagnostic studies of brain

7. Used to:

a. Detect tumors and other abnormalities

b. Monitor effects of surgery, radiation therapy, or chemotherapy on tumors



8. Procedure: performed by a diagnostic imaging technician

a. Patient positioned on motorized table

b. Table moved into CT scanner (doughnut-shaped device)• Until part of body to be examined is inside

scanner



c. Two examinations performed:• Plain scan

• Repeat scan after contrast dye has been injected

– Makes sharper image of internal structures of body

d. Multiple images taken from different angles


CT ScannerCT Scanner

From Kowalczyk N, Donnett K: Integrated patient care for the imaging professional, St. Louis, 1996, Mosby.



9. Computer processes the series of radiographs

a. Results in production of cross-sectional images

– Permanently recorded on film

– Stored digitally on electronic media

b. Evaluated by a radiologist


CT ScansCT Scans

From Snopek A: Fundamentals of special radiographic procedures, ed 4, Philadelphia, 1999, Saunders.



10.Patient Preparation

a. If contrast medium used: fast 4 hours before procedure• Ask patient if allergic to:

– Radiographic contrast media

– Iodine

– Shellfish



b. Patient must remove all radiopaque objects (e.g., metal, jewelry)• Interferes with clear image of body part

c. Patient should lay motionless during procedure

d. Patient instructed to hold breath: when radiograph is taken• Prevents blurring of radiograph

e. Patient hears mechanical clacking sounds as pictures taken


Magnetic Resonance Imaging (MRI)

Magnetic Resonance Imaging (MRI)

1. Newest of advanced diagnostic procedures

2. Used for imaging:

a. Tissues of high fat and water content• That cannot be seen with other radiologic

techniques


Magnetic Resonance Imaging (MRI), cont.



a. Intracranial and spinal lesions

b. Cardiovascular abnormalities

c. Soft tissue abnormalities• Herniated discs

• Joint diseases




4. Allows examiner to see through bone and view soft tissue in great detail

5. Safe and painless6. Strong magnetic field and radio waves:

a. Produce computer-processed images of internal body structures

b. Does not involve radiation• Classified as a low-risk device




7. Procedurea. Patient lies on table inside bore of

cylindrical MR machine• Technician in adjoining room monitors

procedure

b. High resolution, three-dimensional images obtained• Permanently recorded on film

• Stored digitally on electronic media

-Evaluated by a radiologist




8. Due to closed space:

a. Patient may have difficulty with claustrophobia• Physician may order sedative


MRI MachineMRI Machine

From Ballinger PW, Frank ED, eds: Merrill’s atlas of radiographic positions and radiologic procedures, vol 3, ed 10, St. Louis, 2003, Mosby




9. Patient Preparation

a. Safe and painless procedure

b. Completion time: approximately 1 hour

c. No advance preparation• Patient can eat, drink, and take medications

before examination

d. Wear loose clothing to examination




e. Patient must remove: any metal or magnetic-sensitive objects (MRI uses strong magnet)• Watches

• Rings

• Other metal jewelry




f. Patient must remain completely still: for 15- to 20-minute intervals during procedure

g. Patient will hear metallic clicking sound during procedure• Earplugs or headphones available if needed


Nuclear MedicineNuclear Medicine

1. Advanced diagnostic imaging procedure2. Radioactive material

(radiopharmaceutical) is introduced into patient

a. By a nuclear medicine technologist

b. Using one of following methods: • Injection

• Ingestion

• Inhalation


Nuclear Medicine, cont. Nuclear Medicine, cont.

3. Patient placed on a gamma camera

a. Detects radiation given off by the body part• Which has been targeted by the radiation

b. Body parts and organs displayed as:• Still images

• Functional animations



4. Nuclear medicine: can show actual function of organs

a. Provides more detailed information for certain conditions• Than other diagnostic imaging examinations

(e.g., CT, MRI)



5. Radiopharmaceutical: a radioactive material used to target certain body parts

a. Includes:• Technetium-99m

• Iodine-123

• Thallium-201



b. Most radiopharmaceuticals are attached to a tracer • Purpose of a tracer

– Designed to be attracted to:

1) Specific areas of the body

2) Certain types of diseased tissue



6. Most common nuclear medicine procedures:

a. Bone scans• To detect:

– Small fractures (e.g., stress fractures)

– Bone lesions that may not be visible on other diagnostic imaging examinations



• Patient injected with radiopharmaceutical

– Instructed to wait at facility for a predetermined time

– Purpose of waiting period: allow radiopharmaceutical to be absorbed



b. Cardiac studies• Involve two phases:

– Resting: performed with the heart beating at a normal rate

– Stress: Performed immediately after exercising



7. Guidelines

a. Patient may be required to: • Fast

• Abstain from consuming certain foods for a period of time

– MA should relay proper dietary instructions to the patient



b. Nuclear medicine examinations are time-consuming: MA should inform patient of amount of time required• Most examinations require multiple scans

– Interval between each scan determined by:

1) Part being examined

2) Type of equipment used

3) Radiopharmaceutical being used



• May be a need for follow-up images

– Can be done later the same day or following morning

c. Patient must lie still on a table for a prolonged period of time• Advise patient to wear comfortable clothing

d. If examination requires exercise: • Instruct patient to wear appropriate exercise

clothing (including athletic shoes)


Digital RadiologyDigital Radiology

1. Modern advances in digital imaging technology:

a. Transformation of film-based radiology into a system of computer-displayed and stored digital images

b. Advantages:• Increased efficiency and cost savings

• Better patient care

• Higher quality images

• Ability to transfer digital images electronically over the phone lines


Digital Radiology, cont. Digital Radiology, cont.

c. MA may be required to work with images taken by diagnostic imaging facility • Tasks that may need to be performed with

medical office computer

– Access digital images

– Display digital images

– Permanently save digital images


POSTTESTPOSTTEST

True or False1. Wilhelm Roentgen discovered x-rays in 1895. 2. Bone is an example of a radiolucent structure.3. An instrument used to view internal organs

directly is a fluoroscope.4. The patient should be instructed not to move

during a radiographic examination to prevent confusing shadows on the film.

5. The breasts are compressed during mammography to prevent radiation burns.


POSTTEST, CONT.POSTTEST, CONT.

True or False6. After an upper GI is performed, the barium will

cause the stool to be loose and watery.7. Gas must be removed from the colon before a

lower GI study to prevent blurring of the radiograph.

8. Before performing an IVP, the patient must be asked if he is allergic to penicillin.

9. Computed tomography produces a series of cross-sectional images.

10. A radioactive material is introduced into the body before a nuclear medicine imaging procedure is performed.

radiology and diagnostic imaging زمان امتحان : اولین جلسه بعد از عید...

Documents

elsevier items

derived items

imprint of elsevier

radiology slide

film slide

radiant energy slide

disease c

lower gi slide