wk 10 Diagnostic Imaging: Radiology and Ultrasound for the Veterinary Assistant

Role of the Veterinary Assistant

• Assist the radiology technician in acquiring images.

• Use proper technique and restraint to minimize patient stress.

• Adjust machine settings according to the radiology technician's guidance.

• Proper restraint techniques to obtain accurate images and limit multiple exposures.

Types of Radiographs

• Manual Processing: Involves x-ray film and requires darkroom facilities.

• Digital Imaging: Provides internal views crucial for diagnosis.

Manual or Film Radiographs

• Settings Adjustments:

  • Adjust settings based on body thickness and exposure time.

  • Use calipers for measuring patient size.

  • Film development requires a darkroom.

Key X-ray Settings

• Kilovoltage (kVp):

  • Regulates energy of x-ray beam; higher kVp penetrates more tissue.

  • Adjust to correct film density:

  • Increase kVp to darken light films.

  • Decrease kVp to lighten dark films.

• Milliamperage (mA):

  • Controls the quantity of electrons and x-rays produced.

  • Increase in mA increases film density (blackness).

• Exposure Time:

  • Regulates the quantity of x-ray reaching the film.

Caliper Measurements

• Measurements based on the specific view to be taken.

• Calipers must adjust to the patient's size.

Film Handling

• Film must be placed in the cassette securely to prevent exposure to light.

• Cassettes are utilized differently based on the anatomical region being x-rayed (with or without a grid).

Radiation Safety Measures

• Use minimal radiation:

  • Light source for collimating the image area.

  • Ensure proper alignment before taking x-rays.

Film Processing Procedures

• Negative effects of light exposure require film to be developed in a light-tight darkroom using red safe light only.

• Development Steps:

  • Developing, washing, fixing, and drying the film.

• Label film with patient information before developing.

Chemical Safety

• Use protective gear when handling developing solutions: gloves, goggles, and an eye wash station.

• Chemicals are considered biohazard and must be disposed of properly.

Digital Radiography

• Operated via computer; eliminates the need for physical films and darkroom.

• Easier viewing and storage, but requires IT support for maintenance.

Patient Positioning

• Proper restraint and positioning is critical when taking x-rays.

• Assistance required from radiology technician for adjustments based on the patient's weight or size.

Dental Radiographs

• Similar to human dental units, performed under anesthesia.

X-ray Logging

• An x-ray log must document patient information, settings, and personnel involved during the procedure.

Ultrasound Basics

• Ultrasound units are portable but costly.

• Can visualize organ structures, blood flow, and detect foreign bodies.

• Assistant's responsibilities include proper patient positioning and preparation of equipment.

Patient Preparation for Ultrasound

• Abdomen:

  • Place the patient ventrally with optional additional padding for smaller animals.

  • Areas to be scanned should be shaved and prepared with gel/alcohol.

• Cardiac:

  • Begin in right lateral recumbency; flip for additional views.

  • Prepare chest area and apply gel.

Saving Images and Reports

• Ultrasound images and reports should be recorded and saved in patient medical records for future reference.