Canis ISSN: 2398-2942

Radiography: thorax

Contributor(s): Justin Goggin, Patsy Whelehan

Introduction

  • Radiography of the thorax can be problematical due to difficulties eliminating movement blur resulting from breathing.
  • High output (high mA capability) X-ray machines enable exposure times to be minimized, reducing the risk of movement blur.
  • If the machine cannot achieve sufficiently low exposure times, general anesthesia may be required.
    Under anesthesia respiration can be interrupted by gentle pressure on the rebreathing bag, eliminating movement blur, but the lungs must be held inflated.
  • Inflation of the lungs is necessary to make small soft tissue opacities more visible and prevent artifacts from atelectasis.
  • High kV values are preferred for demonstrating the lung fields as this will result in a film of relatively low contrast and high latitude, allowing visualization of a wide range of tissue densities.
  • A higher kV, along with high mA capability, will also facilitate the use of shorter exposure times.
  • A secondary radiation grid is required when patient thickness >10 cm.
  • Close collimation of the primary beam should be practised at all times.
  • The objective is to produce a radiograph which includes the whole area of interest, is correctly exposed and developed, and is free from movement blur and artefacts.
  • The film should be clearly marked with the anatomical marker, the patient's identification, the date and the name of the hospital or practice.

Uses

Advantages

  • Non-invasive, valuable diagnostic tool.
  • Can be performed under sedation if equipment is adequate.
  • Can be performed with no chemical restraint if patient is very sick.
  • Relatively quick and simple where general anesthesia is not required.

Disadvantages

  • May require general anesthesia.
    Placing a dyspneic animals in dorsal or lateral recumbency may compromise respiration in some cases.
    Struggling with a non-compliant, eg undersedated patient may be detrimental to its condition.

Requirements

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Preparation

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Procedure

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Further Reading

Publications

Refereed papers


ADDED