Caylee's Final Study Guide

RADS321 FinalReview 5-9-16

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Test 1 • Caldwell Skull: Petrous pyramids in lower thirds • Maxillary Bones:

• Oral- along with the palatine bones, help form the roof of mouth • Nasal- form part of the lateral wall and most of the floor of the nasal cavity • Orbital- forms part of the floor of all orbital cavities


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Perpendicular

15 degrees 20-25 degrees


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30 degrees


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Test 2: • Zygopophyseal Joints lie @ 90 degrees • Intervertebral Foramina lie @ 70-75 degrees • Scoliosis- abnormal lateral curvature • Good criteria for properly exposed radiographs is the density of the orbital shadows (should be able to see orbital

rims) • Paranasal Sinuses done erect to demonstrate absence of fluid • What is the optimum SID for nasal? 72 • Rhese Method AML Perpendicular • MSP 53 degrees from table (paritoorbital, orbitoparietal, orbitoparietal (rim) • Sinuses (Lateral) CR enters ½-1” posterior to the outer canthus farthest from the IR (Orbits) • Lateral projection of the sinuses demonstrates all of the sinuses • Sinuses- PA Axial (Caldwell Method) OML should be Perp. (If you tilt the Bucky 15 degrees) • Sinuses-PA Axial (Caldwell Method) exits the nasion • Waters Method (Sinuses) demonstrates the maxillary sinus • Sinuses- Open Mouth (Pirie Method) demonstrates the maxillary sinus, and sphenoidal • Sinuses-(SMV) CR enters 3/4 “ anterior t level of EAM


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Test 3:

• Lateral C-spine 85-100 kVp • Emergency room patients or trauma patients, always perform a cross table lateral projection before proceeding

with the rest of the examination of a C-spine • C-Spine- AP Axial projection CR 1-20 degrees cephalic @ C4 • Soft Tissue Neck 75-85 kVp • C-spine-AP Axial Oblique projection, the intervertebral foramina lie 45 degrees from MSP • C-spine-AP Axial Oblique projection, CR is 15-20 degrees cephalic • C-spine-AP Axial Oblique projection, intervertebral foramina are open • T-spine- AP projection, Center @ T7 • T-spine- Lateral projection, if the spine is not // to table CR is directed: males- 15 deg. Cephalic and females- 10

deg. Cephalic • Swimmers Technique for visualization of C7-T1 • Swimmers Technique, CR Perp. To C7-T1 and 2-5 degrees caudal if you need to angle • Swimmers Technique, SS: lower cervical and upper thoracic vertebrae • T-spine- Oblique demonstrates the zygopophyseal joints, patient should be oblique 70 degrees • L-spine, AP or PA projection, 14x17 (CR L4), 11x14 (CR L3) • When the spine is //, CR is perpendicular to enter 1 ½” inferior to the iliac crest and 2” posterior to ASIS, when

the spine is not // the CR is 5 deg. caudal for males and 8 deg. caudal for females • L-spine, AP Axial L5-S1 projection, 1 ½” above pubic symphysis, males- 30 degrees cephalic and females- 35

degrees cephalic • L-spine, AP and PA Oblique projection shows zygapophyseal joints, 45 degrees from MSP • L-spine, PA olique projections RA0/LAO, 2” from the midline of the patient toward elevated side @ level of L3

RAO Demonstrates right

• Zygapophyseal jts


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• LAO Demonstrates Left

• Zygapophyseal jts

• LPO

C-SPINEIMAGESARETHESAMEWAYEXCEPTTHEYAREDEMONSTRATINGTHEINTERVERTBRALFORAMINAWHENOBLIQUED!

Test4:


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RibsPROJECTION IR CR AP or PA Uppers-

Inhalation, Erect, 14x17 LW Lowers- Exhalation, Prone, 10x12 CW

Upper- IR 1 ½” above shoulders Lower- Bottom of IR @ level of crests

AP- Posterior PA- Anterior

AP or PA Oblique’s

Uppers-Inhalation, Erect, 14x17 LW Lowers- Exhalation, Prone,10x12 CW

Upper- IR 1 ½” above shoulders Lower- Bottom of IR @ level of crests 45 degree rotation

AP Obliques (RPO/LPO) Side Down PA Obliques (RAO/LAO) Side Up

APAxialSacrum

2”superiortosymphysis 15,Cephalic

LateralSacrum

CR3½“posteriortoASISand@levelofASIS

0,Perpendicular

APAxialCoccyx

2”superiortosymphysis 10,caudal

LateralCoccyx

CR3½“posteriortoASISand2”inferiortotheASIS

0,Perpendicular

3-7=.70(80,@35mAs)UseahighkVp,lowmAsfor pediatricradiography7yearoldpatientyouwantto doachestxrayinabuckywithagridChildabuseyouwouldreporttothephysicianorradiologistFallingisthebiggestfearforgeriatricsYouaredoingbilaterallowerextremitieshowmanyexposureswouldyouhavetomake?3LowerextremitiesaremostcommonlyperformedwhenitcomestolongbonemeasurementsPatientissupineinalllongbonemeasurementexamsHemothorax=erectchestCT=lessradiationforlongbonemeasurementsBoneagecanbedeterminedbystudyingtheepiphysisHandandwristsradiographscanhelpdetermineageDialysissurveyhelpsdeterminedemineralizationofbonesMetastaticsurvey=Skeletalsurvey

RAOSternum

15-20degreedobliquedCRT7and1”towardelevatedside

LateralSternum

RollshoulderposteriorlyUpperborderofIR1½”abovejugularnotchCRperp.IRenteringlateralborderofsternum

PASCJoints

CRT3

PAObliqueRAO/LAOSCJoints

10-15degreesobliqued


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Angela’s Notes from Tests 1-4 • Skull positioning: • Image of PA projection • Image of 15 degree caudal projection • Evaluation criteria for lateral skull:

o The following should be superimposed: § Mandibular rami § Orbital roofs § EAMs § TMJs

• AP Axial Towne Method o If pt unable to tuck chink, IOML perp to plane of film, CR directed 37 degrees caudal.

• TMJ, Axiolateral projection is the Schuller Method • Axiolateral TMJs, the CR is 25-30 degrees caudal • Image of axiolateral TMJs • Image -label anatomy of orbit

• Facial Bones Positioning: • Lateral Facial Bones

o CR directed perpendicular to midpoint of cassette to enter the lateral surface of the o Zygomatic bone, ½ way between EAM & outer canthus o EC: orbital roofs superimposed

§ Mandibular rami superimposed § Sella turcica no rotated § All facial bones included with zygoma in the center

• Parietoacanthial Projection – Waters Method – IMAGE o MML is perpendicular to the plane of the IR o OML forms an angle of 37 degree angle with the plane of the IR o EC: petrous ridge immediately below the maxillae

• Modified Parietoacanthial Projection – Modified Waters – IMAGE o SS: blow-out fractures of the orbits

§ Looking at the floor of the orbits • Acanthioparietal Projection-Reverse Waters-TRAUMA

o If pt cannot be moved, place CR parallel to the MML • PA Axial Projection – Caldwell Method-IMAGE

o EC: petrous ridges in lower 1/3 of orbits • Lateral Nasal Bones Image

• Zygomatic Arches • SMV – Schuller Method

o SS: zygomatic arches free of superimposition o EC: zygomatic arches free of overlying structures

• AP Axial Towne Method – IMAGE o CR directed 30 degrees caudal, enters the glabella

• Tangential Projection o Useful if pt has depressed fracture of the cheekbones or flat cheekbones

• Positioning of the Sinuses: • Paranasal sinuses should be imaged with the pt erect

• Lateral Projection


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o CR directed perpendicular to midpoint of cassette; enters ½” -1” posterior to outer o canthus farthest from IR o SS: all 4 sinuses visualized

• PA Axial Projection – Caldwell

o Pt will rest head on tip of the nose so that the OML forms a 15 degree angle with the horizontal CR

• Open Mouth Waters – Pirie Method o The sphenoid sinuses projected through the open mouth

• SMV

o Sphenoidal sinuses and ethmoidal air cells are shown

• Orbits • Rhese Method – Parietoorbital oblique projection

o MSP forms an angle of 53 degrees with plane of IR (because optic foramen is o 37 degrees medially)

• Vertebral Column: • Anatomy of vertebra

• Odontoid Image -label anatomy

• Image -label anatomy of the sacrum

• C-Spine positioning: • Emergency room pts or trauma pts – always perform cross-table lateral projection before proceeding with rest of

routine exam

• Lateral shows zygopophyseal joints • Obliques show foramina

• AP Axial Projection

o CR 15-20 degrees cephalic, enters C-4 at the MSP o Image – What is the projection?

• Fuch’s image – when do you perform this projection?

• Lateral projection- what is the kVp range? 85-100

• 2 lateral images given – which is acceptable?

• Image of hyperextension

• Obliques: • AP Axial Obliques RPO/LPO

o Pt is obliques 45 degrees o CR 15-20 degrees cephalic, CR enters C4 o Images – which foramina do you see?


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• PA Axial Oblique RAO/LAO o CR directed 15-20 degrees caudal to C4

• Soft tissue neck: • Go down 10 kVp from lateral C-spine

• T-Spine:

• AP Projection

o Center transversely to the level of T7 o CR perpendicular entering T7

• Lateral

o Image – how can you improve? Perform a Swimmer’s

o If the spine is not parallel to the table, the CR is directed: § 15 degrees cephalic for males § 10 degrees cephalic for females

o Swimmer’s Image – label anatomy and what is the technique/method?

§ C7 can be identified by locating the elevated clavicle, it crosses over C7

• Oblique o The body is oblique 70 degrees from the plane of the film o CR is directed perpendicular to T7 o SS: zygopophyseal joints o Images: what is the position? & what joints do you see?

• L-Spine • AP Projection

o 11x14 cassette center to L3

• Lateral Projection o 85-100 kVp o CR directed perpendicular to: 11x14 – 1 ½” above the crest (L3) o If no support under the lower thorax, CR is angled caudally 5 degrees for males and

§ 8 degrees for females

• Lumbosacral Junction o When the spine is parallel, CR is perpendicular to IR enters 1 ½” inferior to the iliac

§ Crest and 2” posterior to the ASIS o When the spine is not parallel to the IR, CR is 5 degrees caudal for males and

§ 8 degrees caudal for females

• PA Oblique Projections o Images – what position, what joints? – for AP & PA o Oblique 45 degrees


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• Sacrum/coccyx • Sacrum

o AP Axial Projection § CR-15 degrees cephalic § Enters 2” superior to symphysis

o Lateral § 3 ½” posterior to the ASIS and at the level of the ASIS

• Coccyx o AP Axial Projection

§ 10 degrees caudal § 2” superior to pubic symphysis

o Lateral § 3 1/2” posterior to and 2” inferior to the ASIS

• Bony Thorax • The bony thorax consists of: sternum, 12 pairs of ribs, 12 thoracic vertebrae

• Manubrial notch lies at the T2-T3 interspace

• Ribs: • Anatomy

o Spaces between the ribs are called intercostal spaces o Head – expanded posterior end; articulates with the vertebral bodies o Tubercle – articulates with the transverse process of the thoracic vertebra

• Axillary portion of the ribs are best shown in the oblique position

• Ribs above the diaphragm should be done erect

• Erect PA CXR may be part of routine at some hospitals to rule out hemothorax or pneumothorax

o Ribs below the diaphragm: § Exposure made at end of expiration to elevate the diaphragm § Bottom of IR @ the iliac crest

o Obliques:

§ Pt oblique 45 degrees § AP – hurt side down § PA – hurt side up

• Sternum:

o Image – RAO position o For RAO oblique pt 15-20 degrees

• Lateral o 72” SID o Roll shoulders posteriorly, lock hands o Respiration: suspend on deep inspiration

• SC Joints: • Bilateral – rest head on chin


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• CR perpendicular to T3

• Scoliosis: • Scoliosis is abnormal lateral curvature of the spine.

• Use of compensating filters to provide a uniform exposure (radiographic density)

• PA protects gonads and breast tissue in young girls

• Pediatrics: • Radiation protection: use high kVp & low mAs

• Pedi Conversions: (on test was a 6 year old pt)

o 0-1: .25 o 1-3: .5 o 3-7: .7 o 7-13: .9 o Reduce kVp by 2 for every cm difference from the adult and reduce mAs

§ (adult mAs x conversion factor) o Pigg-o-stat – most commonly used device for upright radiography for ages up to 2 yrs

• ?? on test, how to take a CXR of a 10 year old?

• Concerns about child ab use should be directed to radiologist or attending physician

• Geriatrics:

o Skin tears & fall risk

• Long bone measurement: • Lower extremity most commonly performed

• Pt is supine for all exams

• There will be 3 exposures of each limb:

o Upper: wrists, elbows, shoulders o Lower: ankles, knees, hips

• Computed tomography is considered to be more consistently reproduced

• Bone Age: • Bone age can be determined by studying the epiphyses

• Most common radiograph is a PA projection of the wrist and hand

• Dialysis Survey: • Purpose – to evaluate the demineralization of bones

• Hyperparathyroidism:

o Causes an increase in serum calcium due to overproduction of parathyroid o Hormones, which causes bone resorption. This results in bone resorption o Or osteoporosis


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• Bone Metastatic Bone Survey: • May also be called skeletal survey

• Surveys are carried out when metastases are suspected but not know

Final New Information:

Mobiles and Surgery: Principles of Mobile Radiography

• Performed in: • Patient’s rooms • ER • ICU • Surgery • Recovery • Nursery/Neonatal Units

• Some machines are designed for transport by: • Van • Automobile • To nursing homes, extended care facilities, or other off-site locations requiring radiographic imaging

services Mobile X-Ray Equipment

• When patients can’t come to the department for imaging, we must go to them. It is then a portable or mobile procedure

• These 2 terms are not interchangeable: 1. Mobile Equipment:

• Equipment that is capable of being moved • Mounted on wheels • Can be pushed by human or mechanical power

2. Portable Equipment: • Equipment that is capable of being carried with the implication that it does not need (in theory

anyway) more than one able bodied person to do the carrying at any given time • Instead of Portable we should call it- Mobile

• Portable means it can be packed up and setup somewhere else, like a field unit Mobiles & Surgical Radiography

• Mobiles is an area of diagnostic radiology without standard routines • Most common mobile procedures are:

• Chest • C-spine • Abdomen • Extremities in traction

• Typical mobile machine has kVp & mAs settings • kVp Range- 40 - 130 • mAs Range- 0.04 – 320 • Total Power of the Unit Range- 15 – 25 kilowatts

• Some mobile units have preset anatomic programs • Mobile X-Ray Machines are Classified as:


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• Battery Operated • Capacitor Discharge

• AEC is available on some mobile units: • The paddle containing the ionization chamber is behind the IR • The paddle is used to determine exposure time

• Direct Digital Capability: • Image is acquired immediately on the unit • Uses a flat panel detector similar to those found in a DR table bucky • The detector is usually connected by:

• Tethered cord • Communicates through wireless technology

Mobile X-Ray Machines

• Battery Powered Mobile Unit: • GE machines are a primary example of this type of equipment • Contain (up to as many as ten) 12-volt lead acid battery packs connected in series which operates a drive

motor and the x-ray tube • The batteries are usually maintenance free • Batteries should last up to 2 years

• Maintenance should include: • Plugging in only when battery is low • Usually when the batteries are fully charged, charging stops and a neon light will indicate a full

charge • Normally plug in every night and on weekends • Check acid levels every 2 weeks

• Driving Mechanism • Forward/Reverse

• A strong “deadman” type of brake is standard, which means the machine stops instantly when the push handle is released

• Advantage of this type of mobile unit: • Cordless • Provides constant kVp & mAs

• Circuitry differs from the stationary unit • Have an inverter, which changes the battery DC voltage to 1 kHertz (1000 Hz) AC • Then it has rectifiers which change AC back to DC for the tube

• Includes full wave rectification provided by means of selenium rectifiers • Full wave rectification allows greater efficiency

• Technical Considerations

• Grids: • General Rules:

• Keep IR and part as parallel as possible • Grid use is critical in mobile imaging • Grid must be level to prevent “cut-off” • Grids most often used: 6:1 or 8:1 focal range 36”-44” • Be familiar with the type of grid that is being used:

• Focused- specific SID is critical • Linear


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• Also, know the grid ratio for technique considerations • Keep CR perpendicular to the part

• Anode Heel Effect: • Causes a decrease in density under the anode side of the tube • More pronounced with:

• Short SID • Larger field sizes • Small anode angles

• Know the anode/cathode orientation of the tube to best utilize this effect • SID:

• SID should be 40” for most mobile exams • Longer distances of 40”-48” require increased mAs to compensate for increased distance • The mA limitations of a mobile unit necessitate longer exposure times when SID exceeds 40” • Therefore, the result could be motion artifacts especially when imaging children/infants or the

critically ill adult patients • Radiation Safety

• Mobile radiography produces some of the highest occupational radiation exposures for radiographers • Radiation safety for radiographers, other is immediate area, and patient is extremely important • Radiographer must:

• Wear a lead apron • Stand as far away from the patient, tube, and use beam as the room and exposure allow

• Recommended minimal distance: 6’ (2m) • Most effective means of radiation protection is distance • The radiographer should inform all persons in the immediate area that an x-ray exposure is about to occur • Lead protection should be provided:

• For any individuals who are unable to leave the room • For individuals who may have to hold a patient or IR

• Shield patient’s gonads • Source-to-skin distance cannot be less than 12” in accordance with federal safety regulations

• Gonadal Shielding

• For the following situations: • X-ray exams performed on children • X-ray exams performed on patients of reproductive age • Any exams for which the patient requests protection • Exams in which the gonads lie in or near the useful beam • Exams in which shielding would interfere with imaging of the anatomy that must be shown

• Isolation Considerations: • Two types of patients to consider:

1. Patients who have infectious microorganisms 2. Patients who need protection from potentially lethal microorganisms

• Make sure the mobile unit is properly cleaned and disinfected to prevent transmission of infectious microorganisms

• Preliminary Steps before Performing Exam: • Announce your presence to nursing staff, etc.; ask for assistance if needed • Determine that the correct patient is in the room • Introduce yourself to the patient and family • Observe equipment in the room, IV poles, etc. • Ask family members/visitors to leave


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Mobile X-ray Equipment • C-Arm- implies mobile Fluoroscopy • X-ray tube head and image intensifier are mounted so that they are at opposite ends of a C-arm • X-ray tube at lower end and image intensifier at upper end with its input phosphor facing towards the x-ray tube • Tube can be on top when positioning

• Not recommended because it increases the OID • This also increases the exposure to the head and necks of the operator and surgery team

• At the back of the image intensifier is a TV pickup tube, either a 675-line vidicon (more common) or 875-line plumbicon

• C-Arm Mounted on a Cross-Arm • Tube head, stationary anode, dual focal spot (0.3-1.0 mm) has a 5:1 grid • Input phosphor: Cesium Iodide • Field Sizes: 5”, 6”, & 9” • Control console mounted on wheels

• TV Monitor & Control Cart: • 2 Monitors Needed:

• One for the active image • One for “Image Hold” (still image) • Generally active on left and hold on right

• Operation Mode:

• Mag Mode- magnify image- so surgeon can better visualize structures that are frequently viewed from distance

• Pulse Mode- to create a pulsating x-ray beam at timed increments to reduce exposure • Snapshot or Digital Spot Mode- activates “digital spot”; results in a higher quality computer enhanced

image as compared to a fluoro image • Film Mode- for exposing standard cassette; cassette holder attached to image intensifier tower

• Converts machine to conventional mobile radiography unit • Additional Operational Modes:

• Subtraction (digital subtraction)- self-explanatory • Road Mapping- method of image display

• A specific fluoro image is held on screen in combination with continuous fluoro • Especially useful for placement of catheters and guide wires

• Foot Pedal- fully equipped, has multiple pedals • Scout Fluoro- unprocessed fluoro • Digital Process Fluoro- activates computer enhanced processing • Image Save- saving of last image displayed • Snapshot or Boost Digital Spot

Mobile Radiography

• 3 Key Accessories for Mobiles Are: 1. Grid cassettes 2. IR holders 3. Slip-on Grids

• Common Accessories: • Sponges • Tape • Rolled sheets • Sand bags • Lead aprons


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• Mobile Chest • Most commonly performed mobile procedure • Remember CR perpendicular to cassette; Part parallel to cassette • Make sure to not produce a lordotic image

Surgical Radiography Operating Room Attire

• Masks • Shoe covers • Caps • Gloves • Dosimeter • Proper ID

Personal Hygiene

• Persons with infection not permitted to enter OR suite: • Cold • Open cold sore • Sore throat • Known to be carrier of transmittable conditions

• Daily body & hair cleanliness to prevent transportation of microbial fallout which could cause open wound infections

Surgical Radiography

• Requires a good knowledge of aseptic technique • Aseptic Technique- means free from germs or “without infection”

Extremity Examinations

• Choose appropriate size of IR to include all anatomy and hardware Working in a Sterile Field

• Patient is draped with sterile sheets to provide an antibacterial barrier between the patient and the sterile attired team

• Sterile attire in surgery reduces the air-borne contamination because sterile attired persons touch sterile items • Sterile attire is from waist up and only the front • Sterile attired persons should pass front to front or back to back • When in doubt if an object is sterile, consider it non-sterile • When contamination occurs, it is called a Strike Through

Radiographic Equipment for the Operating Room

• Three important hazards to consider when using mobile radiographic equipment in OR: 1. Risk of Infection- a mobile unit is used throughout hospital and if not properly cleaned, could bring

infection into OR • Manufacturers have designed features on the mobile units to help in the cleaning process of the units

2. Risk of Explosion • Because anesthetic gases are used in OR:

• Using electrical equipment that may produce a spark (static electricity- friction) could be explosive

• This risk is decreasing because anesthetic gases which readily ignite or promote ignition are now less often used


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• Mobile units have wheels with special conducting rubber to prevent static 3. Radiation Risk to Everyone in OR

• Most ORs have their own supply of lead aprons • It is the responsibility of the RT to remind everyone in OR that x-rays will be used and assist them in

getting lead aprons • The greatest amount of scatter occurs on the tube side of the machine. Best to have fluoroscopic tube

under the patient (ex. C-arm in surgery) • Also, if tube is under the patient, the shielding should also be under the patient • The source-to-skin distance should not be less than 12”

Time Saving

• Another important factor in OR • The OR team has to subject the patient to anesthesia and open surgery for the shortest possible time • Therefore, rapid radiographic results are necessary • Mobile fluoro units with an image intensifier are one way to save time • The radiographer must remember that if they are operating fluoro in the absence of a radiologist • The responsibility of radiation safety is carried by the radiographer • This gives the radiographer an authoritative voice should not hesitate to speak even to the most senior surgeons if

radiation dose to patient and staff appears unreasonably high • It is the radiographers ultimate responsibility to communicate with the anesthetist or anesthesiologist to assure

that breathing has been stopped before the exposure Radiation Safety

• Highest occupational exposure • Wear lead apron • Distance- 6’ recommended • Shield patient gonads • Source-to-skin distance cannot be less than 12”- federal safety regulations

• Reading Assignment: Merrill’s Volume III p.1-18

Anatomy of the Spinal Cord

• Conus Medullaris- most inferior portion of the spinal cord at the lower border of L-1 • Filum Termiale- a fibrous strand that extends from the terminal tip of the cord

• Attaches the cord to the upper coccygeal segment • Cauda Equina- spinal nerves that extend below the termination of the spinal cord

• Resembles a horse’s tail


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Nervous System

• Any traumatized patient with possible CNS involvement • Begins with a cross-table lateral C-spine • Rules out fractures & misalignment of C-spine • Approximately 2/3rds of significant spine pathology can be detected on this image

Spinal Cord Injuries

• Level of injury is helpful in predicting what parts of the body might be affected by paralysis/loss of function

• Cross-table C-spine would be followed by CT before going into a true nervous system examination • Routine spine images will assess:

• Narrowed disk space • Degeneration of the disk • Osteoarthritis • Post-op changes

Radiographic Examinations of the Nervous System

• Cerebral Pneumography- is outdated, historically, need to know it was an exam of the brain; involved injecting contrast into the ventricular system • 2 Types of Cerebral Pneumography:


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1. Pneumoventriculography- inject contrast directly into the ventricular system; Burr holes are associated with this exam

2. Pneumoencephalography- inject contrast into subarachnoid space via a spinal puncture Myelography

• It is a general term used for radiographic exam of the CNS structures located within the spinal cord • (Myelos- marrow; spinal cord)

• Performed by introducing a contrast agent into the subarachnoid space via a spinal puncture (intrathecal injection) • Purpose is to Demonstrate:

• Extrinsic spinal cord compression caused by a herniated disk • Bone fragments • Tumors • Swelling resulting from traumatic injury

• Contrast agents may be opaque or gaseous: • Opaque Agents:

• Oil Based (Pantopaque): 1942 • Used for many years • Must be removed following exam • Did not coat thin areas such as nerve roots in lumbar region

• Water-Soluble Iodinated (Isovue, Omnipaque) • Most commonly used today • Coats nerve roots better than pantopaque • Does not have to be removed • Less irritating to spinal cord • Absorbed quickly, causing more post myelographic headaches • Inject slowly or it will dilute • When using omnipaque, patient is to be well-hydrated • Will provide good contrast for at least 30 minutes

• Gaseous Medium • Is absorbed quickly • Does not mix with CSF well

• Procedure Preparation: • Must be performed under aseptic technique • Clean table & overhead equipment before patient’s arrival • Attach footboard and shoulder supports • Have sterile tray & non-sterile items required for injection & spinal puncture

• Patient Preparation: • Discontinuance of neuroleptic drugs for at least 48 hours (drugs for psychotic behavior) • Maintain normal diet up to 2 hours prior • Ensure hydration fluids up to procedure

• Examination Procedure: • Explanation to patient

• Maneuvers • Why head is placed in full-extension (to compress the cisterna magna to prevent contrast from

entering the ventricles) • Assure patient of safety during procedure • Optional: Scout film of the area of interest

• Lumbar


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• Cervical • Placement for Spinal Puncture:

• Prone on cushion or lateral with flexion • Puncture done under aseptic technique

• Lumbar region usual site for spinal puncture: usually L2-L3 or L3-L4 • Cervical Puncture: at the cisterna magna between C-1 & occipital bone

• Physician will withdraw small amount of spinal fluid & replaced with contrast agent • Rate of injection is slow or over 1-2 min. • Amount is 9-12cc (same amount for single or complete)

• Then view contrast travel fluoroscopically • Spot filming along the way • Must keep patient head elevated above spine to prevent CM from going superiorly past the

clivus & entering into the ventricles • Do not lower head of table more than 15ᵒ • Ventral Decubitus: marking the IR at the posterior surface of the body (side UP) or cross-table lateral

(Center where band-aid is)

Lumbar Myelogram

• 14”x17” LW for PA or Cross-table Lateral • 40” SID • 70-80 kVp • Large focal spot • Cross-Table Lateral:

• CR Perpendicular to IR center • Entering at needle or puncture site • Must include from Conus Medullaris to Filum Terminale

• PA: • CR Perpendicular to IR center • Enter over puncture site


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Cervical Myelogram

• 10”x12” for PA, Cross-table Lateral, or Swimmer’s • 40” SID • 70-80 kVp • Large focal spot • Cross-Table Lateral:

• CR Perpendicular to IR center • Enters C-4 • Top of IR at TEA

• PA: • CR Perpendicular to IR • Enters level of C-4

• Swimmer’s: • 40” SID • CR Perpendicular to IR center • Enters C-4 • Top of IR at TEA

(Left) Prone, Cross-table lateral projection showing CM passing through foramen magnum & lying against lower clivus

(arrows) (Right) Cervical Myelogram: AP projection showing symmetric nerve roots (arrows) & axillary pouches (a) on both sides

& spinal cord Complete Myelogram

• Perform both Lumbar & Cervical Myelograms • Thoracic area only by request

Post Procedure Care (Omnipaque)

• Most Physicians Recommend: • Elevate head at least 30ᵒ-45ᵒ during recovery • Slow movement • Close observation for at least 12 hours • Encourage oral fluids • Follow department protocols

Computed Tomography Myelography (CTM)

• Involves CT examination of the vertebral column after the intrathecal injection of a water-soluble contrast agent • CTM demonstrates the size, shape, & position of the spinal cord & nerve roots • Useful in Patients With:


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• Compressive injuries • Extensive dural tears resulting in extravasation of CSF

MRI

• Allows clear visualization of areas of the CNS normally obscured by bone • Preferred modality for evaluating the middle cranial fossa & posterior fossa of the brain & spinal cord • Spinal Cord: (Direct Visualization)

• Cord • Nerve roots • Surrounding CSF

• Paramagnetic IV Contrast: Gadolinium • Helpful in Assessing:

• Demyelinating diseases such as Multiple Sclerosis • Spinal cord compression • Post-radiation therapy changes in spinal cord tumors • Metastatic disease • Herniated disks • Congenital anomalies of the vertebral column

(Left) CT myelogram of lumbar spine demonstrating subarachnoid space narrowing (arrows)

(Right) Sagittal MRI of lumbar spine demonstrating distal spinal cord & cauda equine (arrows)

Diskography or Nucleography

• General term used in examinations of individual intervertebral disks • Purpose:

• Investigation of internal disk lesions, such as rupture of nucleus pulposus (HNP- Herniated Nucleus Pulposus), which is not demonstrated on myelography

• A small quantity of water-soluble iodinated CM injected into the center of the disk using a double needle entry


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The nucleus pulposus has ruptured & is leaking Facet Injection

• This examination is diagnostic & therapeutic • Diagnostic- finds level of pain • Therapeutic- temporarily relieves pain

• This procedure indicates to the physician where the pain is originating • Uses a number of spinal needles, usually 22g if doing 3 levels; bilaterally, need 6 needles

• Depomedrol- 80mg/mL (steroid) • Marcaine 50% (nerve block) • Xylocaine 1% (numbing agent)

• 3cc syringe for each level that is done containing 1cc of each of the following: • Depomedrol, Xylocaine, & Marcaine

• & a 10cc syringe of Xylocaine • Procedure:

• Place patient in oblique position, if left side is affected- RAO; elevated side is side of interest • Make injection under fluoro • First 10cc of Xylocaine, then 3cc syringe

• 3cc syringe goes directly into facet • After examination, patient gets dressed & walks around to see if it helps

Vertebroplasty & Kyphoplasty

• Used for treating compression fractures or other pathologies of the spine • Procedure:

• Minimally invasive procedure • Uses fluoroscopic guidance to place a large needle into the vertebral body • Injection of iodinated contrast to confirm location

• Serious Complications: • Most Common Complication: leakage of cement before it hardens • Pulmonary embolism & death is rare, but have been reported • Techs need to educate patient & ensure that informed consent has been documented

Percutaneous Vertebroplasty

Knowdrugs,notdosages!


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• Injection of radiopaque bone cement into a painful compression fracture under fluoroscopic guidance • Injection hardens in 10-20 minutes • Advantages:

• Stabilizes fractures, relieves pain, & increases mobility within 48 hours • Eliminates pain in over 90% of patients • Continues to provide pain relief for years • No open surgery • No hospitalization

Bone cement injected during Vertebroplasty under image guidance

Percutaneous Kyphoplasty

• Percutaneous Kyphoplasty sometimes referred to as “Balloon-Assisted Vertebroplasty” • Procedure:

• Differs from vertebroplasty in that a balloon catheter is used to expand the compressed vertebral body to near its original height before injection of the bone cement

• After the balloon is deflated, a cement-like substance is injected in the bone (very similar to Vertebroplasty) Lumbar Epidural Steroid Injections (LESI)

• Considered C-arm procedure (Non-Ortho) for program comp • Epidural steroid injections used to treat low back pain • Procedure:

• Patient receives medication intravenously for relaxation (mild sedation) • Then a numbing medication is injected into the skin area where injection will take place • Using fluoro, the needle is inserted into the epidural space of the affected area • Following injection, patient is moved to recovery area and monitored for approximately 1 hour

Documents

Caylee's Final Study Guide