Settings, Positioning, Collimating & Centring - Answers

Arlo Guthrie — Tue, 21 Apr 2009 07:18:31 GMT

Current Revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 4/21/2009 7:18:31 AM

ANSWERS

List the details required for an exposure chart.
- Part of the anatomy radiographed.
- Positioning of the patient.
- Film-screen combination.
- FFD.
- Type of grid used (if applicable).
- Kilovoltage (kV).
- Tube current (mA).
- Milliampere seconds (mAs).
What are the preferred techniques for the labelling of radiographs?
- Lead letters.
- Perspex tablets.
- Lead tape.
  NB. All above are primary labelling ie. put on before processing.
Why are the answers to Q2 preferable to chinagraph pencil or light markers?
They are all permanent, unlike chinagraph pencil (secondary labelling, after processing) or light markers.
What information must be present on a BVA KC hip dysplasia scoring scheme radiograph?
- Kennel club reference number.
- Date.
- Left or right marker.
List 6 positioning aids used in radiography.
- Foam blocks and wedges in a variety of sizes.
- Sandbags.
- Ties.
- Sticky tape.
- Troughs.
- Wooden blocks.
Whilst cranio-caudal (Cr.Cd) and caudo-cranial (Cd.Cr) are used to describe radiographic views above the radiocarpal and tibiotarsal joints, what nomenclature describes the views below these joints?
- Dorso-palmar (D.Pa) or palmaro-dorsal (Pa.D) for a forelimb.
- Dorso-plantar (D.Pl) or plantaro-dorsal (Pl.D) for a hindlimb.
Why are thoracic radiographs usually taken on inspiration?
To enable a better view of the lung fields.
What positions are suitable for heart radiographs and why?
- Right lateral recumbency - heart outline is more consistent in shape.
- Ventral or sternal recumbency - avoids tipping the heart to one side (as in dorsal recumbency).
Why are abdominal radiographs usually taken on expiration?
To enable a more spread out view and thus better visualisation of the viscera.
Why must a dyspnoeic patient not be placed in dorsal recumbency (ventro-dorsal position)?
Any condition where pleural effusion is suspected can be worsened to such a degree that this may result in the death of the patient. Pneumothorax and ruptured diaphragm are examples. Always take special care in RTA and shock cases.
In spinal radiography, why is it preferable to perform a series of x-rays rather than simply one view of the vertebral column?
The divergence of the x-ray beam means that shadows will be cast upon the disc spaces by adjacent vertebrae. A spinal survey will help to prevent this, and thus reduces the possibility of vital information being missed.
What position is required for the BVA KC Hip Dysplasia Scheme?
Ventro-dorsal with extended hips. The beam is centred on the pubic symphysis.
When would it be advisable to use the flexed (or "frog-legged") view of the pelvis?
In traumatised patients where manipulation of the hips or pelvis may prove painful, or in cases of suspected fracture where manipulation could cause displacement.