This section is an experiment to evaluate the use of the web
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The notes do not pertain to be a complete description of all
projections possible, rather a selection of the basic most
common projections.
The common elements of technique will be present below.
Accessories:
Fine and standard/regular resolution, film speed screen
combinations in an assortment of sizes.
Pads and immobilisation aids.
Cones and Plates to fit equipment being used.
Hard surface disinfectant for bucky board or head support.
Anatomical Markers
Anatomical markers placed on the cassette at the time of
exposure with the correct PA AP orientation is the preferred
standard in general use in the UK. Additional special radio
opaque markers may be used in special circumstances. Anatomical
markers should be placed in the primary beam away from any
relevant anatomical structure and the correct way up / round.
Collimation
Collimation to include the required structures within the
size of the film required is generally the best description,
reducing the volume of tissue irradiated reduces the dose to the
patient.
Evidence of collimation on four sides equally around the centering
point
However collimation may sometimes be compromised by the
need to center over a specific point such as a joint space, and
include for example the lower third of the tibia and fibula in
imaging the ankle, in this case the distal collimation may not
be visible and may be off the film.
Collimation in general should be such that the radiosensitive
organs such as the thyroid, eyes, gonads and breasts receive the
least dose commensurate with the image required.
Immobilisation
Full immobilisation is essential for high quality diagnostic
imaging, the use of supporting devices, Velcro binders and pads
will assist in immobilising the patient in most cases.
Indication for Imaging
Will be based on the Royal College of Radiologists Guidelines
FFD Focus to Film Distance
In general radiographic imaging is performed at two common
FFD's
100cm and 180cm, in general the 100cm is used for non bucky work
where there is little magnification, and 180cm when there is
increased risk of magnification, however in bucky work must be
performed at the required FFD for the grid involved, this is
most commonly between 100 and 130 cm with some specialised skull
units using values less than 100cm.
Patient Identification ( Click here for
link to sample policy)
Before starting any examination, the identity of the patient
must be checked by the radiographer; a patient may answer to a
name not his/her own. If the patient is fully compus mentus, the
radiographer should ask the patient their name and date of
birth, these must match the request form, Inpatients must have
their ID bands checked and they must match the request card.
Patient Preparation
Basic psychological preparation with reassurance and
explanation of technique.
Patients referred for radiography may be worried and anxious
about the outcome, some patients, are difficult to handle and
may need special care, typically the very young, old
physically and or mentally infirm, unconscious or unable to
co-operate, The assistance of a nurse or other competent person
may be required. An understanding and tolerant attitude
exhibited by the radiographer always helps. Time taken to
explain the test to the patient is never wasted.
All detachable artifacts must be removed from the image area,
long hair must be tied out of the way, if possible monitoring
leads /pads should be removed for the duration of the
examination.
It is important to remember the dignity of the patient, and
essential to have clean hands, a clean cassette or bucky stands
and clean immobilisation aids at all times.
Radiation Protection
The 10 or 28 day rule will apply as required (see
SP8 in the regulations section)
Methods
for reducing doses to patients should be followed at all
times.
Where possible beam should be pointed away from the gonads or
most radiosensitive organs, there should be direct lead rubber
gonad protection whenever possible taking into account the possibility
of back scatter from equipment. The most effective method of
dose reduction is careful technique to avoid the need for repeat
radiographs.
"Kings Lynn" Gonad protection during pelvic
imaging (Click
here for more details)
Position for female patients
 The shaded
area is constructed of 2mm of lead
Position for male patients
 The shaded
area is constructed of 2mm of lead
Patient position
Accepted terminology related to the Normal Anatomical Position
will apply.
Normal Anatomical Position
1 Coronal Plane. 2 Median Saggital Plane. 3Axial Plane
Body Planes
(Bontrager, Textbook of Radiographic
Positioning and Related Anatomy, 3rd Edition, Mosby)
Patient / Film Identification
All radiographic images should have the following details
legible and actinically marked on the film before processing,
Patients name, examination number, date and hospital name, and
be placed in the departmentally accepted position away from any
anatomical structure of interest.
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