Radiographic Anatomy Flashcards Preview

First Quarter > Radiographic Anatomy > Flashcards

Flashcards in Radiographic Anatomy Deck (58)
1

Properties of an X-ray

-travel straight lines at the speed of light
-diverge in space from the source
-cause certain crystals to flourecence
-cannot be detected by the human eye
-differential absorbtion
-cannot be refracted by lens
-produce biological effects

2

Clinical use

-harmful effects identified as ALARA
as low as reasonably achievable

3

Advanced Imaging

-computed tomography (CT)
-magnetic resonance imaging (MRI)
-Myelography (w/wout CT)
-diagnostic ultrasound
-nuclear medicine
-dual energy X-ray absorption (DEXA)
-mammography

4

Producing a radiograph

-minimal equipment: X-ray source->image recorder->subject
-xray beam travels from source, thru subject, to the film

5

Image formation

-x ray tube, source of electrons
-xray beam, focused source of photons based on density
-object, beam absorbed or passed based on density
-film, photons pass object to strike film with silver coating
Image - record of proton interactions

6

Xray Photons

produced when electrons hit the target

7

Xray photon interactions

xray photons penetrate object, absorbed or pass thru to hit film

8

Xray beam

-is cone shaped from a point source
-the most central portion is called central ray
-the central ray diverges less and gives the truest image
-typically the beam will be perpendicular to the film

9

Differential Absorbtion

-penetration dependant on density
-denser object=less penetration
-move beam striking film=dark
-less beam striking film=whiter

10

Tissue Density

-a product of type of tissue and thickness
-results in differential absorbtions
-increase tissue density = whiter
-decrease tissue dens = darker

11

Differential Absorbtion

black - Air (lungs, trachea,outside of body)
fat (parietal fat, fascial fat)
water (muscle, organs)
bone (bone, atherosclerotic placing)
metal (filling,markers,orthodevices)

12

X ray photon Pass thru

non dense object
air and soft tissue
immage apears blacker
radioleucent appearance

13

Xray photons absorbed

-by dense object
-metal and bone
-image appears white
-radioopaque appearance

14

Image Terminology

Projection
Body Position

15

Projection

Anteroposterior/Posteroanterior - x ray beam enters AP front to back or PA back to front
Lateral - x ray beam enters side project side of patient alone coronal plane and travels left to right, names for which side is against the film
Oblique - positioned on film so X-ray passes thru at 45 degree angle

16

Body Position

Upright - AP or PA or lateral
Recumbent - supine or prone or lateral
Oblique - right or left and anterior or posterior
Decubitis - laying on side and take PA or AP

17

Upright Positions

patient stands
allows for veal to postural information
chiros can use this to analyze upright lumbar and sacral

18

Recumbent

patient laying down
no reliable evaluation of postural elements
useful when patient is in a lot of pain

19

Minimum Diagnostic Series

-standard views required to evaluate an area
-variation by facility or circumstance
-add more views depending on case
-must take at least 2 views
-projection oriented 90 degrees to one another
-view 3D object in 2D

20

Choice of Postioning

place the structures closest to the film
starts with standard series
what structures you wish to visualize
patients clinical presentation
different diagnosis under consideration
patients size
patients protection (female pelvis)

21

Film Markers

Informational markers
Mitchell Markers
Name blockers
ID markers - Type of study, Clinic and Tech

22

Informational Markers

provide information about patient
provide information about the doctor and or facility
identifies side of patient or patient positioning

23

General marker rule

without a marker you cannot identify which side of the patient is the left and which is the right

24

Mitchell Markers

metal markers
taped to cassette
label anatomical side of patient
label side of patient
usually contains BB's
BBs at centre of bubble and are gravity dependant

25

Markers are also used to ID

type of study
patient positioning
technologist
facility

26

Name Blocker

Patients name
Patients gender
Patients age
Doctors name
Facility where films were taken
Date of study

27

View a Radiograph

composite shadowgram
-profiles/shadows/outlines
-structures added contrasting densities
-superimposition
in a profile vs on end

28

Composite Shadowgram

represents the sum of the densitites interposed b/w the beam source of the film
involves superimpostion of object and orientation of objects

29

Projection

orientation of beam, position of object will affect image
Superimposition
objects that lie on the same path

30

Collimation

shutters that block peripheral portions of beam
limits area exposed to beam, uses most central portion of beam
limits size of xray beam field
uses smallest area possible
decreases the scatter radiation
decerases the patients dose
acheives better dose
tube light stimulate xray beam

31

Compat bone

Cortex
outer shell of bone
encloses meddulary bone
covered by periosteum
homogeneous density

32

Spongy Bone

Cancellous
network of trabecula

33

Long / Tubular Bone

Epiphysis - articular end of the bone
Metaphysis - tappering portion b/w the physis and the shaft
Diaphysis - shaft of the bone

34

Periosteum

fibrous layer of bone
membranous bone formation, attachment of tendonous and ligmanets
contains vascular supply
not distinguishable on a radiograph

35

Apophyses

tuberosity, tubercles, trochanters, processes, spinous processes
osseous projections
develop to support and resonce of forces

36

Radiographic Evaluation and Interpretation

differentiate normal from abnormal
localize abnormality
describe abnormality
list pertinant positives/pertinant negatives
give impression of clinial significance

37

Radiographic evaluation

have a systm
use the system every time
be thorough

38

Extent of Evaluation

you are legally responsible
evaluate the whole xray
evaluate for all pathologies/conditions

39

Method of Evaluation

A - alignment
B - Bone
C - Cartilage
S - soft tissue

40

Search Pattern
Steps in Evaluation

know the ABCS for each region
steps: - identify the study
-identify the informational markers
- note collimation, shielding and artifacts
-the the technical quatlity of the film
- evaluate anatomy using ABCS search pattern

41

Normal Anatomy

the first step om recognizing abnormalities on radiographs is to know the appearanfce of notmal radiographic anatomy
-each person is a unique anatomical entity
-anatomical variations exist that are normal or abnormal
-pathology ften alters anatomical structures
-may be present with no radiographically visible alterations in anatomical structures

42

Abnormal Anatomy

know pathology, learn patients history, ID patients clinical presentation put it all together, radiographs are not isolated, it represents patient

43

Method of Evaluation

compare one side to the other
compare one level to the adjacent lebels

44

Cervical Spine Standard Series

neutral lateral
AP lower cervical
APOM open mouth

45

Lateral Cervical (neutral lateral)

you want all 7 cervical vertebrae and have the base of the skull
head and neck in a neutral position (hard palate level)

46

The 5 Assessing Cervical Lines

Paravertebral Lines - rules of 2s and 6s
Anterior Body line - smooth curve, no interuptions
Posterior Body line- Georges line, eval vert bodies
Spinolaminar Line - line thru spinolaminar junction
Spinous Process Interspacing- spacing of SP's

47

Atlantodental Interspace (Interval)

space b/w post aspect of C1 anterior tubercle and the anterior aspect of odontoid process
adults < 3mm
children 8-10yrs <5mm

48

McGregor's Line

Posterior-superior margin of hard palate to inferior most surface of the occiput
tip of dens to the line: <10mm in females

49

Relevant soft tissues of the Lateral Cervical

pharyngeal air shadow
laryngeal air shadow
tracheal air shadow
note calcification of cartilages
posterior cervical soft tissues

50

AP lower cervical

used to visualize the structures of C3-C7 vertebral bodies
-good to also see the postior elements but they come in variavle in size
see the articular pillars and SP's and other oblique structures

51

AP Open Mouth

used to visualize the structures of C0-C1 articulation and the C1-C2 joint space
-you also see the lateral masses of C1 and the arches
-odontoid process, paraodontoid notches, body of C2, skull, madible, and dental structures

52

Georges Line

Lateral spine (neutral, flexed, or extended)
a line is drawn along the posterior aspect of the vertebral bodies to extrapolate across disc space
-offset indicates anter or retrolithesis having a translation of >= 4mm as the indicator

53

Sagittal Dimention of Cervical Spine Canal

lateral cervical
posterior surface of mid vertebral body to spinolaminar junction
-there are minimum measurements for this one at each vertebral body
C1-16mm, C2-14mm, C3-13mm, C4-7-12mm
positive shows the patient may have canal stenosis

54

Atlantoaxial Alignment

seen on the AP open mouth
lateral mass of atlas should not overhang lateral margin of C2 superior facet (>1mm)
>=2mm overhang shows the patient may be suspect to a Jefferson's fracture
this may be normal in children 4 years of age or younger
you can draw an X from one C0-C1 joint to the opposite C1-C2 joint and the and by doing the same on the other side you can determine rotation at the C1-C2 joint

55

Coronal Dimensions of the Cervical Spine

measure the shortest distance between the inner cortical margins of pedicles at given segment, cary by spinal level, evaluated for stenosis

56

Cervical Gravity Line

Lateral neutral cervical
vertical line drawn through the apex of odontoid process should pass through the seventh cervical vertebral body
gross assessment of where the gravitational stresses are acting at the C/T junction
Ruth Jackson stress lines on flex/extension can also assess stress focus

57

Angle of Cervical Curve

lateral cervical
two lines are drawn, one through and parallel to the inferior endplate of the 7th cervical body and the other through the midpoints of the anterior and posterior tubercles of the atlas
construct perpindiculars and measure the angle, normally 35 - 45 degrees
lack of lordosis may indicate trauma, muscle spasm, or degenerate disease
many stress lack of correlation between curve and symptoms

58

Prevertebral soft tissue

lateral cervical
space measured between the vertebral bodies and the air shadow of the pharynx, larynx and trachea
normally 10mm at C1
rules of 2's and 6's
C2 < 6mm
C6 < 22mm
increases with any soft tissue mass (hematoma, abscess or tumour)