Radiology Positioning and Radiation Safety in the Clinic

Why Radiology Skills Matter for Veterinary Assistants

Diagnostic radiographs are among the most common procedures performed in a veterinary clinic. A well-positioned image gives the veterinarian the information needed to diagnose fractures, detect masses, evaluate organ size, and assess lung fields. A poorly positioned image must be repeated — which means additional radiation exposure for the patient and staff, added cost, and delayed diagnosis. Your role as a veterinary assistant during radiology is to position the patient correctly using aids, verify that everyone in the room is protected, and maintain accurate records. You will always work under the direct supervision of a credentialed veterinary technician or veterinarian.

Radiation Safety Fundamentals

All ionizing radiation carries risk. The guiding principle in veterinary radiology is ALARA — As Low As Reasonably Achievable. Every decision you make should minimize the total radiation dose to patients, yourself, and your coworkers.

Distance is your single most effective protection. Radiation intensity decreases with the square of the distance from the source (the inverse-square law). Standing even a few extra feet from the X-ray tube during an exposure dramatically reduces your dose.

Shielding involves placing absorbing material between you and the beam. Lead aprons and thyroid shields are required PPE for anyone who remains in the radiology suite during an exposure. Lead gloves must be worn if a hand must be near the primary beam — though this situation should be avoided whenever possible through positioning aids.

Dosimetry badges (film badge or optically stimulated luminescence [OSL] dosimeters) are worn on the collar or lapel, outside the lead apron, to monitor cumulative radiation exposure over time. Badges are issued individually — never share a badge. They are sent to a dosimetry service on a regular schedule (typically monthly or quarterly) for reading. If a badge is lost or forgotten, note it in the log and inform your supervisor.

Occupational limits are set by state radiation control programs based on federal guidelines. You do not need to memorize the exact numbers, but you must understand that pregnant workers and minors have additional restrictions — always follow your clinic's policy.

Personal Protective Equipment Checklist

Before every exposure session, confirm that every person in the room has:

• A properly fitted lead apron (wrap-around or front-panel, as appropriate)
• A thyroid shield (collar)
• Their assigned dosimetry badge worn at collar level, outside the apron

Document PPE compliance in the radiology log before the first exposure of the session. If any item is missing, the study waits until it is corrected. This is a non-negotiable patient and staff safety rule.

Standard Radiographic Views

Lateral thorax and lateral abdomen: The patient lies on its side (right lateral or left lateral as ordered). The spine and sternum should be parallel to the tabletop, with no rotation. Use foam wedges under the sternum or neck to prevent the body from tilting. Sandbags can secure limbs away from the area of interest.

Ventrodorsal (VD): The patient lies on its back, spine down, with the body symmetrical. A V-trough supports the patient in this position. Limbs are gently extended away from the body. VD views are common for abdominal and thoracic studies.

Dorsoventral (DV): The patient lies on its sternum. DV thoracic views are often preferred for cats and dyspneic patients because sternal recumbency is more comfortable and less stressful for a patient struggling to breathe.

Using Positioning Aids Instead of Manual Restraint

Manual restraint inside the primary beam is prohibited. Your hands must never be in the path of the X-ray beam during an exposure. Use the following aids:

• Sandbags: Draped over limbs or across the neck to hold position without human contact in the beam
• Foam wedges: Placed under body parts to prevent rotation or tilt
• V-troughs: Support VD and DV positions without manual holding
• Tape and ties: Gently secure limbs to the table or trough

If a patient is too fractious to position safely with aids alone, inform the supervising technician. Chemical restraint (sedation) is a veterinarian decision — do not proceed with a study on a dangerous patient without escalating to your supervisor.

Completing the Radiology Log

Every exposure session must be documented. A complete log entry includes:

1. Date and time

2. Patient name and species

3. Views obtained (e.g., right lateral thorax, VD abdomen)

4. Exposure settings if using digital or computed radiography (kVp, mAs)

5. Name of the veterinarian who ordered the study

6. Name of the credentialed technician who performed the study

7. PPE compliance confirmation

8. Any repeat exposures and the reason

Accurate records protect the patient, the clinic, and you. Radiology logs are legal documents and may be reviewed by state radiation control inspectors.

Competency Expectations in This Rotation

During this rotation you will assist with at least 10 radiographic studies. At least 8 of those 10 must be rated diagnostically acceptable by your supervising technician. Radiation safety compliance must be 100% on every session — one lapse in PPE or badge use requires you to repeat the lesson. Use every study as a learning opportunity: ask your supervising technician to review the image with you and explain what makes it diagnostic or what you could improve.