Foreign bodies

Soft tissues- Nothing bony

Foreign bodies- A mass or particle of material that is not normal to the place where it is found.

• Get a good pt history
• Ensure Image receptor is clean and artefact free
• Use radiopaque marker to show entry wound on resultant images
• Take a flexible approach.

Limited use for imaging soft tissue

Reduce kVp for penetrating foreign body/ies in throat.

Cassette and IR must be clean

Utilise image manipulation as much as possible

Fluoroscopy is 65% sensitive and is usefuk to guide the removal, glass and metal, Not good for wood or plastic.

Very sensitive for soft tissue imaging.

Image manipulation and windowing are excellent

Good visualisation of FB in the orbit

Very high dose

Excellent for soft tissue

Useful to isolate foreign bodies not seen on isolation

Contact is required. Wounds can be a problem

Excellent for soft tissue imaging

Very disease sensitive

More scan planes to aid detection

Never for metallic foreign bodies

Claustrophobia

Penetrating

• Glass
• Metal
• Wood
• Plastic

Accidental ingestion/ Deliberate ingestion- double condom sign, button vs battery

Inhalation/aspiration- 3 year olds most at risk

FB in the eye

FB post-surgery

FB inserted into various body cavities.

Coin vs Button battery- 3 year olds are most at risk of ingestion. Button batteries are v dangerous. They can be differentiated by looking for a double rim sign.

Drug conveyance-

Double condom sign -  A lucent rim of air trapped between multiple layers of latex, which may be less evident with well machine wrapped packages.

Tic Tac Sign- Multiple oblong uniformly shaped packages

Rosette sign - Air trapped in the knot where the condom is tied

Radiographic density of packages- The density of the ingested packet is variable and is determined by the type of wrapping material used, ranging from densely radio-opaque aluminium to radiolucent wax and the contents of the packet.