Thoracic spine plus scoliosis- from the book

AP projection: position of part (5 things)

1. MSP of body to midline of grid 2. supine: flex pts hips and knees (to place thighs in vertical position) 3. upright: weight equally distributed on both feet (to prevent rotation of spine) 4. place superior edge of the IR 1.5-2 in above shoulders (puts T7 in middle of image) 5. suspend respiration at end of full expiration

scoliosis: position of part lateral (4 things)

1. MSP parallel to midline of grid 2. MCP perp to midline of grid 3. pt extends arms out of way 4. respiration- suspend

AP position: evaluation criteria (3things)

1. all 12 vertebrae 2. no rotation demonstrated by spinous processes at the midline of the vertebral bodies 3. vertebral column aligned to the middle of the image

scoliosis: position of part PA or AP (3 things)

1. ensure ASIS are equidistant from IR 2. center MSP to midline of grid 3. respiration - suspend

scoliosis: evaluation criteria (2 things)

1. entire spine 2. vertebral column aligned down the center of the image

Lateral projection: position of part

1. keep long axis of the vertebral column horizontal (might need pillow) 2. flex pt's hips and knees for comfort, superimpose knees if possible 3. superior edge of IR 1.5-2 inches above relaxed shoulders 4. center posterior half of thorax to midline of grid and level of T7 5. pt's arms at right angles to long axis of body to elevate ribs (to clear the intervertebral foramina) 6. respiration: "breathing technique" or end of expiration

scoliosis: CR (2 things)

1. perp to center of IR 2. 2-3 images taken

Lateral projection: CR (3 things-think about angulation for genders)

1. perp to center of IR at level of T7 2. enters at posterior half of the thorax 3. angle CR 10* (female) to 15* (male-greater shoulder width) cephalad if the vertebral column is not elevated to a horizontal plane when the pt is recumbent

Lateral position: structures shown (4 things)

1. thoracic bodies 2. intervertebral disk spaces 3. intervertebral foramina 4. lower spinous processes

AP position: structures shown (5 things)

1. thoracic bodies 2. intervertebral disk spaces 3. transverse processes 4. costovertebral articulations 5. surrounding structures

Lateral position: evaluation criteria (4 things)

1. vertebrae clearly seen through rib and lung shadows 2. 12 thoracic vertebrae, T1-3 are not seen well due to shoulders 3. ribs superimposed posteriorly to indicate pt was not rotated 4. open intervertebral disk spaces

which thoracic vertebrae have single whole facets ar their superior margin?

10-12 for articulation with the 11th and 12th ribs (floating ribs)

the ___#___ thoracic vertebra presents a demifacet on its inferior border for articulation with the head of the 2nd rib

1st

the body of the ___#___ thoracic vertebra presents a WHOLE costal facet near its superior border for articulation with the head of the 1st rib

1st

Lateral projection: if we use the breathing technique how long is the exposure time and what do we have do to our mA (raise/lower)

2-3 seconds with a corresponding DECREASE in mA

the bodies of which thoracic vertebrae have superior and inferior demifacets for articulation with the ribs?

2nd-8th

the __#__ through the __#__ spinous processes project inferior and overlap. the vertebrae above and below are less horizontal/vertical/inferior/anterior

5th-9th vertical

Lateral position: collimation

7 x 17

AP position: collimation

7 x 17in

to show the zygapophyseal joint space, the pt must be rotated ___-___ degrees from the anatomic position or ___-___ degrees from the lateral position

70-75* 15-20*

PA or AP oblique projection: collimation

7x17 inches

which thoracic vertebra has only a superior demifacet?

9th

the palpable tip of each spinous process of the 5th-___th vertebrae corresponds in position to the interspace above/below the vertebra from which it projects

9th below

LPO and RPO are used for AP/PA oblique projections this is used to image zygapophyseal joints farther from/closer to IR

AP oblique joints farthest from the IR

PA or AP oblique projection: upright position of part for AP (7 things)

AP oblique rotate body 20* posteriorly, arm adjacent to grid brought forward to avoid superimposition of humerus on thoracic vertebrae, have pt place outer hand on hip coronal plane forms an angle of 70* from plane of IR vertebral column centered to grid, pts adjacent shoulder rested on IR IR 1.5-2 inches above shoulder to center IR to T7 pt shoulder in horizontal plane weight of pt body equally distributed respiration: suspend at end of expiration

PA or AP oblique projection: AP was recommended by Oppenheimer/Fuchs PA was recommended by Oppenheimer/Fuchs

AP-Oppenheimer PA-Fuchs

PA or AP oblique projection: AP oblique shows joints closest/farthest from IR PA oblique shows joints closest/farthest from IR

AP-farthest PA-closest

T-spine can be hard to evaluate with x-ray for extremely large pts and those with fluid-filled chests. this is why ______ is often used to see the vertebrae in detail

CT

which projection includes thoracic and lumbar spine for a scoliosis case

Ferguson method

which projection includes cervical, thoracic and lumbar spine for a scoliosis case

Frank ET AL. method

LAO and RAO are used for AP/PA oblique projections this is used to image zygapophyseal joints farther from/closer to IR

PA oblique joints closest to the IR

PA or AP oblique projection: upright position of part for PA (7 things)

PA oblique: rotate body 20* anteriorly, flex elbow of arm adjacent to grid and rest hand on hip, have pt grasp side of grid with outer hand. coronal plane forms an angle of 70* from plane of IR vertebral column centered to grid, pts adjacent shoulder rested on IR IR 1.5-2 inches above shoulder to center IR to T7 pt shoulder in horizontal plane weight of pt body equally distributed respiration: suspend at end of expiration

which position is used to show the zygapophyseal joints

PA or AP oblique

T/F AP projection: using the anode heel effect ensures a more uniform exposure of the thoracic anatomy

True

PA or AP oblique projection: recumbent position of part for AP oblique

adjust lower arm at right angles to the long axis of the body, flex elbow, place hand under or beside the head, place arm posteriorly pt is in LPO or RPO, rotate body anteriorly or posteriorly 20* so coronal plane forms 70* angle with horizontal IR 1.5-2 inches above shoulders centered at T7 respiration: suspend at end of expiration

PA or AP oblique projection: evaluation criteria (3 things)

all 12 thoracic vertebrae PA oblique-zygapophyseal joints closest to the IR AP oblique- joints farthest from the IR

radiation intensity decreases towards the cathode/anode side this is why we orient the pt so the lower thorax is at the ___________ end of the x-ray tube. taking advantage of the anode heel effect

anode cathode

each process has on the anterior/posterior/lateral surface of it a small concave facet for articulation with the tubercle of a rib, with the exception of the ___ and ___ vertebrae

anterior 11th and 12th

the zygapophyseal joints angle anteriorly/posteriorly approx. __#__-__#__ degrees to form an angle of 70-__#__ degrees to the MSP of the body except the inferior articular processes of the ___th vertebra

anteriorly 15-20* 75* 12th

scoliosis: collimation

collimation depends on extent of pts scoliosis

bending studies may be included, primary curves do/ don't change when the pt bends and secondary curves do/ don't change when the pt bends

don't do

scoliosis: structures shown

entire spine from base of skull to coccyx

what is a demifacet

half a facet

bodies of the thoracic vertebrae decrease/increase in size as you travel down from 1st to 12th vertebrae?

increase

inferior/superior thoracic bodies resemble lumbar bodies

inferior

Lateral projection: pt position

lateral recumbent (left lateral preferred)

PA or AP oblique projection: recumbent position of part for PA oblique

lower arm behind back and upper arm forward with hand on table pt is in LAO or RAO, rotate body anteriorly or posteriorly 20* so coronal plane forms 70* angle with horizontal IR 1.5-2 inches above shoulders centered at T7 respiration: suspend at end of expiration

what causes scoliosis

may be idiopathic or caused by disease, surgery, or trauma

the transverse process of the thoracic vertebrae project _____ ______ and ______

obliquely, laterally, and posteriorly

how can you find the level of T7

palpate the inferior angle of the scapula

the intervertebral foramina are _________ to the MSP therefore they are clearly shown with the pt in a ______ position

perp true lateral position

AP position: CR (2 things)

perp to IR centered halfway b/t the jugular notch and the xiphoid process

PA or AP oblique projection: CR

perp to IR exiting or entering at level of T7

the typical vertebral bodies are deeper posteriorly/anteriorly and their _________ surface is concaved from side to side

posteriorly posterior

costal facets for articulation with the heads of the ribs are anterolateral/posterolateral

posterolateral

each lamina is broad and thick and they overlap the ____________

subjacent lamina

inferior/superior thoracic bodies resemble cervical bodies

superior

AP projection: pt position (2 things)

supine or upright head on table or pillow to avoid accentuating thoracic kyphosis

if the upper thoracic vertebrae are of interest, what view can you include in your images. what anatomy can obscure the upper thoracic vertebrae

swimmer's lateral shoulders

we raise the arms of the pt so that...

the ribs are elevated and dont cross over the intervertebral foramina

PA or AP oblique projection: structures shown

thoracic zygapophyseal joints

Lateral position: why is a sheet of lead rubber behind the pt suggested

to absorb scatter radiation that may darken and decrease the quality of your image

Lateral projection: why do we use the breathing technique

to blur the pulmonary vascular markings and ribs

why do we suspend respiration at end of full expiration

to minimize the air in the lungs which results in less attenuation differences and more uniform exposure of the thoracic anatomy

Lateral projection: why is the left lateral position preferred

to place the heart closer to the IR to minimize superimposition of the vertebrae by the heart

Lateral position: why is a greater SID recommended, what SID is recommended

to reduce magnification 48 inch

why do we prefer to image scoliosis in a standing position

to use the force of gravity to show the degree of curvature

the bodies if the typical thoracic vertebrae are approximately _________- in form which vertebrae are the "typical" thoracic vertebrae?

triangular 3rd-9th

PA or AP oblique projection: pt position

upright or recumbent

Lateral position: why is setting a fixed technique recommended

using AEC may cause the image to look underexposed

AP position: can this projection be improved with a compensating filter

yes

the younger/older the pt, the easier it is to show the upper thoracic bodies

younger