Why is it so useful to be able to do standing MRI scans?
Hallmarq manufactures the only MRI system that allows scans of the equine foot and lower limb to be done in a standing position without general anaesthesia. This unique ability has come about as the result of years of research and development.
But why is this an advantage?
Firstly and most importantly, a large published study into anaesthetic deaths in horses1 concluded that there is a 1% risk of death from anaesthesia in healthy horses. This means that with other MRI systems your horse needs to be anaesthetised and there is a small but significant risk to his or her life.
This risk is of course multiplied if follow-up MRI scans are required.
While it is necessary to sedate the horse for a standing MRI in order to ensure no movement and good image quality, the procedure is quicker than when full anaesthesia is required resulting in safer, more cost-effective scans.
A recent study at the Animal Health trust comparing results using the Hallmarq standing MRI system and a ‘high field’ anaesthetised system concluded that there was no difference in diagnostic ability. This work will be published in due course.
The Hallmarq system does offer the flexibility, based on clinical needs, to do anaesthetised scans as shown.
1 Johnston G.M., Taylor P.M., Holmes M.A. and Wood J.L.N. (1995) Confidential enquiry of peri-operative equine fatalities (CEPEF): preliminary results. Equine vet J 27 193-200
Hallmarq's MRI system
The Hallmarq standing equine MRI system was first developed in 2001 and over 60 systems have been installed around the world since that time.
On the basis of the clinical experience gained by scanning several thousand horses and new innovations by our development team, Hallmarq released a new model, the EQ2, in late 2006.
The EQ2 platform is unique to Hallmarq and has been developed specifically to meet the requirements for scanning the standing equine, providing high quality clinical images for efficient image reading and diagnosis.
EQ2 includes improved motion correction capabilities for gradient echo, spin-echo and fat suppressed STIR MR sequences
For the more difficult horse or the more challenging location (eg the tarsus) the short imaging time of the EQ2 protocols allows rapid and convenient scanning of a horse under general anaesthesia.
Equine-specific RF coils
MRI scanners collect their data from a radiofrequency 'coil' fitted around the target region. Hallmarq has developed a range of coils to fit the most commonly scanned regions of the standing horse. The coil clips around the leg and transfers data to the computer via a cable. Sometimes the scan operator will use bandages or padding to hold the coil in place.
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