Nuclear Scintigraphy (Bone Scan)
Nuclear scintigraphy, or bone scanning, is performed on over 100 horses per annum, usually as a part of a lameness evaluation, but also in some cases as a part of the evaluation of neurological or other conditions.
This imaging modality gives an overview of bone turnover in the area imaged and is incredibly sensitive for detecting even subtle changes in bony turnover to help localise skeletal abnormalities. We have a Mediso gamma camera mounted on an overhead gantry that permits imaging of the entire horse.
The horse is injected with a special radioactive dye that binds to bone. After a few hours have passed allowing the dye to bind to the bone, the camera that detects the gamma radiation is used to scan the horse and generates images, thereby giving information about bone turnover.
Before the scan
- If your horse is insured, you should inform your insurance company that your horses requires a nuclear scintigraphy examination and, where appropriate, check that the insurers are prepared to cover the costs of this. Where possible this should be done well in advance of your appointment date. You can download our guide for insurance HERE.
- Owners need to arrive with their horse (and its passport) the afternoon before or by 9.30am on the morning of the scan (or by special arrangement at other times). There is no need to starve the horse prior to admission
- To improve the quality of the images obtained, the horse should be kept in work for the 2 weeks prior to the bone scan, unless your vet advises against this
- If your horse is admitted the morning of the scan, please place stable bandages all round and rug your horse the previous evening to ensure the horse is warm; these should be kept on during travel. This helps to ensure good blood flow which helps with image quality
- Shoes do not routinely have to be removed for bone scans unless the horse is shod in bar shoes and the feet are being imaged: please ask your vet for clarification
- Owners need to bring with them the rugs that the horse would normally wear. We will supply hay / haylage and hard food (any specialist food should be bought along with the horse)
The scanning procedure
- Unless we are advised to the contrary, the horse will be lunged on the morning of the scan to ensure good blood flow. Stable bandages will be placed prior to the scan to help keep the extremities warm and aid blood flow.
- A small patch on the neck will be clipped and cleaned and an intravenous catheter will be placed to allow injection of the radioactive drug and sedative drugs during the procedure. Please inform us if you have any objection to the horse being clipped.
- Horses are injected with the radioactive drug intravenously between 10.00 am and 1.00 pm on the day of the scan, and are ready to be scanned two hours later. Once injected the horse becomes ‘radioactive’. As a result of the radioactivity the horse is confined to a controlled area (in effect a normal stable) for 48 hours after the injection, and for safety, owners are not permitted to visit the horse during this period.
- For safety reasons, the horse will not be routinely mucked out whilst the stable remains a Controlled Area. This is because the horse will pass the radiation in the urine. Handling of the horse is also kept to a minimum during this time, but the horse will be checked regularly and receives fresh food and water as normal.
- The scan is performed under standing sedation (i.e. not general anaesthesia). Dependent on the regions to be scanned and the temperament of the horse, the procedure can last anything up to two hours. It is not possible for owners to be present for the scan due to radiation safety rules.
- Once scanned the horse is taken back to its stable and left for the radioactivity to decay.
- Approximately 48 hours after the scan, when the horse is no longer radioactive, then further work-up, such as X-rays or nerve blocks, may be performed to follow up any findings from the bone scan. For horses having further work up at Bell Equine, clients will be advised when to come and collect their horse, subject to progress with further investigations. Occasionally it is necessary for the horse to be kept in for more than the standard 3-4 days to allow more time for further diagnostic procedures. Horses which have been referred for bone scan with further work up to be performed by the referring vet will normally be ready to collect after midday, 2 days after the scan.
- Clients will normally be informed of the bone scan findings during the 48hours after the scan. For horses which have been referred for bone scan only, we endeavor to inform referring vets of the scan results as promptly as possible so that the client can discuss findings and further diagnostic/treatment plans with their own vet.
- The very strict procedures in place are to minimise the exposure of staff to radiation, and are a legal requirement. This is necessary as we perform approximately 200 bone scans per year. The single dose of radiation that the horse is exposed to during the procedure poses no known risk to its health