1 RT 124 SPRING WEEK 1 – Part 1 CHEST & ABD A “Self Study” Review Rev Spring 2010

1

RT 124 SPRINGWEEK 1 – Part 1CHEST & ABD

A “Self Study” Review

Rev Spring 2010

2

RT 124 - WEEK 1 (Part 2)is the Lecture Presentation for:

Chest II AP: SUPINE, SEMI-UPRIGHT – UPRIGHT

R & L DECUBITUSLATERAL – PT ON GURNEY OR IN W/C

ABDOMENAP SUPINE, UPRIGHT, LLD

RT 124 – Wk 1 – Part 1 Lecture on web can be reviewed for basic CHEST & ABD anatomy.

3A quick review of CHESTDedicated Chest Unit

• X-ray machine designed to perform routine chest imaging– tube has fixed alignment with

imaging plate (IP)

– when tube moves, IP moves

– Non-CR has film unit• includes stationary grid• magazine to hold unexposed

film• direct hook-up to processor

[or magazine for exposed film]

• ID flasher on unit

Digital Chest Unit

4Body Habitus

5

6CASSETTES W/ GRID CAPS

7

8

9Grids

• Allow primary radiation to reach the image receptor (IR)

• Absorb most scattered radiation

• Primary disadvantage of grid use – Grid lines on film

10

11CR GRIDS

12

CHEST

ANATOMY REVIEW

13

Chest Anatomy• Thoracic cavity

(chest)– Surrounded by

boney thorax– Separated from

abdomen by diaphragm

• Muscular partition• Dome shaped• Lungs drape over

diaphragm

14

Bony Thorax

• ENCLOSE THE ORGANS– STERNUM (breast bone)– 12 PAIR OF RIBS– 12 THORACIC

VERTEBRA

• ATTACH UPPER EXTREMITY– 2 CLAVICLES– 2 SCAPULA

AnteriorPosterior

15

Thoracic Cavity• Sections of the thoracic cavity

– Pleural portion (lungs)– Mediastinum (between lungs)

– Pericardial portion (heart)

16

Respiratory System

1. Lungs – Lobes

• Right 3 lobes• Left 2

lobes

– Terminology• Apex• Hilum• Base• Costophrenic angles

A A

H H

B B

C

C

17

Bronchial Tree2. Bronchi

– Air tubes leading into the lung

– Right more vertical than left

– Branching structure• Primary 2ndary

teritiary...

– Only primary visible on PA projection

P

18

Trachea3.Trachea

– In mediastinum– Passageway for air

to/from lungs– Approx. 4½" Long– Air visible on images

T

19

Circulatory System1. Heart

– 4 Chambered pump

2. Great blood vessels– Aorta– Vena cava– Pulmonary Artery

• Not seen on image

A

VC

VC

PA

20

Miscellaneous• Mediastinum

contents– Trachea– Major vessels– Esophagus– Lymphatics– Heart– Thymus

21

Chest Examinations• Most common projections

– PA in an erect position– Right to left lateral in an erect position

• Less common projections– AP -- erect or recumbent position– Lateral decubitus

22

Routine PA & L Lateral1. Erect position

– Diaphragm moves more inferior– Demonstrates air-fluid levels– Prevents blood pooling in gr. vessels

2. 72" Sid– magnification of heart

23

Routine PA & L Lateral (cont.)

3. Breath held on inspiration– Expands lung fields– depresses

diaphragm– Provides contrast

(air vs. tissue)

4. Film (adult)14X17 lengthwise

(may be crosswise on broad chested male)

inspiration expiration

24

Routine PA & L Lateral (cont.)

5. Technical factors– High kVp (>100)

• long scale contrast

– High mA & short time• reduces motion

– AEC– Grid

• decrease scatter on image

25PA Projection

(erect anterior position)• Patient

– Standing -- weight on both feet

– Anterior chest against IP– MS plane perpendicular

to IP & floor– Chin raised– Posterior of hands on

hips or machine “hug”– Shoulders depressed &

rotated forward

26

PA Projection (cont.)

• X-ray beam– CR

• to film• in MS plane at T 7

• Collimation (very little)

– Full length of film– To lateral edges of

patient

27

PA Projection (cont.)

• Film evaluation– Complete anatomy shown

• apices (chin elevated)

• base (both costophrenic angles)

• scapulae out of lungs (shoulder rotation)

• respiration (10 posterior ribs)

28

PA Projection (cont.)

• Minimal rotation– Symmetry of SC

joints– MS plane to

lateral ribs = distance

29

PA Projection (cont.)

• Technique– Vertebra seen through

heart (kVp)– "Good" density

• Other– no film artifacts– no motion (blur)

30PA Chest Anatomy

31

Radiographic Anatomy -- PA

32

Erect Left Lateral Chest• Patient

– Standing with weight on both feet

– L side against film holder– Chin raised– Arms elevated &

immobilized– Align MS plane

• parallel to the film to the floor

33

Left Lateral Chest (cont.)

• X-ray beam– CR

to film• in midaxillary plane at

level of T7

(slightly lower than T7 ok)

– Collimation• full length of film• to anterior & posterior

surfaces of patient

34

Abdomen Anatomy• Abdominopelvic

cavity– Abdomen

• diaphragm to pelvic inlet

– Pelvic cavity• pelvic inlet to floor

muscles of the cavity

35

Abdomen Anatomy (cont.)

• Abdomen– Divisions

• 4 Quadrants (clinical)

• 9 Regions (anatomic)

36

Abdomen Anatomy (cont.)

• Boney anatomy– lower ribs & T11-T12– lumbar spine (5)– sacrum & coccyx– innominate (2)

• iliac portion• ischial portion• pubic portion

– femur• head & neck• trochanters

37

Abdomen Anatomy (cont.)

• Topographic (positioning) landmarks– Iliac crest (level of L4-5)

– Anterior superior iliac spine (ASIS)

– Greater trochanter of femur

– Pubic symphysis

Symphysis Pubis

GreaterTrochanter

LumbarVertebra

IliacCrest

ASIS

38

Abdomen Anatomy (cont.)

• Major muscles (radiographically)– Diaphragm– R and L psoas muscles

39Major Abdominal Organs

stomach

large bowel

spleen

small bowel• duodenum• jejunum• ileum

liver (triangular)gall bladder

pancreas

40Urinary Organs & Major Vessels

aorta

kidney

ureter

vena cava

urinary bladder

urethra

adrenal glandadrenal glandadrenal glandadrenal gland

47

Abdominal Radiography• Patient preparation

– KUB & acute abdomen• Remove radiopaque clothing & gown• Otherwise "as is“

• Breathing instructions– Expose after patient exhales– "Take deep breath, blow it all out, stop breathing"– Watch patient while giving instructions

– Contrast media exams• Dietary & bowel preps usually required

48

Abdominal Radiography (cont.)

• Exposure factors (non contrast media)– Medium kVp -- 70-80

• adequate penetration• moderate contrast

– Short exposure time• decrease involuntary motion on image

– Enough mAs for sufficient density• Film markers• Radiation protection

– Check for pregnancy on all women– Gonadal shielding (???)

• Collimation– to film edge top & bottom– to patient width on sides

49

Abdomen • AP projection, supine position

– KUB, flat plate, plain film, scout film

• Patient position -- Supine on table with– pillow for head– support sponge for knees– arms at but away from

sides– legs extended, internally

rotatedMidsagittal plane• perpendicular to table• parallel to table length

– R & L ASIS level– Shoulders level

50

Abdominal Radiography (cont.)

• Film & centering– 14X17 cassette

lengthwise in table bucky

– Center of film at level of iliac crests

– CR to center of film passing through the MS plane at level of iliac crests

• adjust to include pubic symphysis at lower edge of film

51

Abdominal Radiography (cont.)

• Film evaluation– No rotation

• symmetry of pelvis & spine

– Complete anatomy with no motion

• vertebral column in center of image

• symphysis pubis at bottom of image

• kidneys, liver, spleen at top of image

52

Abdominal Radiography (cont.)

– density & contrast adequate to see

• Psoas muscles• lumbar transverse

processes• ribs• kidney & liver margins

53

Other Abdominal Projections/Positions

– AP projection in an erect position

• CR 2" above iliac crests in MS plane

– AP or PA projection in a lateral decubitus position

• CR 2" above iliac crests in MS plane

54

Abdominal Radiography (cont.)

– Lateral in a recumbent or erect position

• Seldom done due to level of radiation

• lack of significant diagnostic information