Chp 1: Terms , Positioing, & Imaging Principles

50% of population; average body habitus

Sthenic

35% of population; leaner than average body habitus

Hyposthenic

5% of population; broad & stocky body habitus

Hypersthenic

10% of population; thin & slender w/long & narrow body habitus

Asthenic

how should the IR be placed if the pt has a hyposthenic body habitus for a chest xray? Why?

portrait/lengthwise bc lungs are longer

how should the IR be placed if the pt has asthenic body habitus for a chest xray? Why?

portrait/lengthwise bc lungs are longer

how should the IR be placed if the pt has a hypersthenic body habitus for a chest xray? Why?

landscape/crosswise bc lungs are shorter & wider

how should the IR be placed if the pt has a sthenic body habitus for a chest xray? Why?

can be portrait/lengthwise or landscape/crosswise depending on age, height, & pathology

what plane is this?

sagittal plane

what plane is this?

coronal plane

what plane is this?

horizontal/transverse/axial plane

longitudinal or transverse plane at an angle or slant & not parallel to the other planes

oblique plane

divides body into EQUAL left & right

midsagittal plane

divides body into EQUAL anterior & posterior

midcoronal plane

what is PA?

posteroanterior projection; CR enters posteriorly & exits anteriorly

What is AP?

anteroposterior projection; CR enters anteriorly & exits posteriorly

what is the difference between projection & position?

projection describes the pathway of the CR while position describes the physical placement of the pt’s body relative to the IR

most oblique xrays are____ degrees

45

AP & PA oblique projections must include____

term indicating which way its rotated (e.g., medial or lateral rotation)

medial & lateral sides of mediolateral and lateromedial projections are determined w/pts in ____

anatomical position

when marking AP & PA projections as well as oblique, pt’s right side will always be on the viewer’s ____

left

specific AP axial chest projection to see apices of lungs

AP lordotic projection

type of special projection where CR skims body part

tangential projection

type of special projection where CR enters superiorly & exists inferiorly or vice versa

superoinferior/inferosuperior axial projection

oblique & decubitus positions will be named based on ____

part of body touching or closest to IR

ex: dorsal decubitus- pt is supine & horizontal beam is being used

ex: RAO- right anterior oblique. pt’s right side of chest (anterior) is closest/touching IR & they are in an oblique position

what is the difference between recumbent and decubitus position?

recumbent simply means pt is lying down. Decubitus is specifically when pt is lying down while a horizontal xray beam is being used

caudad CR angle

CR is angled towards feet and away from head

cephalad CR angle

CR is angled towards head

lateral projection thru thorax. Requires right or left lateral position term to indicate which shoulder is closest to IR

transthoracic lateral projection

when would a transthoracic lateral shoulder projection typically be done?

when a pt has severe trauma where they cannot move their shoulder to conduct a regular shoulder projection

dorsoplantar/plantodorsal projection

CR enters from the dorsal (anterior) surface of the foot & exits thru the plantar (posterior) surface & vice versa

an axial plantodorsal projection (PD) is used to image

calcaneus

CR enters cranial parietal bone & exits at acanthion

parietoacanthial projection/PA Waters

CR enters acanthion & exits at cranial parietal bone

acanthioparietal projection/ AP Reverse Waters

acanthion

junction of nose & upper lip

CR enters below chin (mentum) & exits at top of skull (vertex)

submentovertical (SMV) projection

CR enters at top of skull & exits below mandible (less common)

verticosubmental (VSM) projection

ipsilateral

on the same side of the body or part

contralateral

on opposite side

ulnar deviation

turn or bend the hand & wrist towards the ulnar side

radial deviation

turn or bend the hand & wrist towards the radial side

eversion

outward stress movement of foot at the ankle

inversion

inward stress movement of foot at ankle

valgus

abnormal position where a part of limb is forced outward from midline of body. sometimes used to describe eversion stress of ankle

varus

abnormal position where a part or limb is forced inward toward midline of body. sometimes used to describe inversion stress of ankle

____is not a correct positioning term in the U.S. This term should be “restricted to discussion of a radiograph or image” produced

view

for most radiographic procedures, a minimum of __projections should be taken as near as possible to 90 degrees from each other

2

all bones involving joints require a minimum of ___projections

3

what requires 2 projections as routine?

• forearm

• humerus

• femur

• hips

• tibia fibula

• chest

what requires 3 projections as routine?

• fingers

• toes

• hand

• wrist

• elbow

• ankle

• foot

• knee

a ___ study only requires 1 AP projection unless a hip injury is suspected

pelvis

for bones that require 3 projections, what type of projections are required?

• AP or PA

• lateral

• oblique

which 2 landmarks should not be palpated?

• ischial tuberosity

• symphysis pubis

lateral positions are marked left or right by

side of the pt closest to IR