An introduction to equine ultrasonography
Ultrasound technology has advanced in leaps and bounds over the last few years and this has had a huge positive impact on veterinary diagnostic imaging across all species. Ultrasonography has long been a key tool in the diagnostic investigation of equine musculoskeletal disorders, and slightly more recently has facilitated great advances in the field of equine reproduction.
As technology continues to develop the possibilities for the use of ultrasound as a diagnostic tool will expand, and increasing affordability of high quality equipment should help drive this. Below are some things to consider regarding the use of ultrasonography in equine practice, including its potential applications and the equipment required.
Indications
Musculoskeletal
- Tendons and ligaments of the distal limb, e.g. SDFT core lesions
- Pelvis, e.g. ilial wing fractures
- Joints, e.g. meniscal injury in the stifle
- Spine, e.g. cervical facet joints
Reproductive
- Pre-breeding, e.g. uterus and ovaries
- Pregnancy diagnosis, foetal sexing and twin management
- Monitoring of the health of a pregnancy, e.g. CTUP measurements
Abdominal
- Colic exam
• Assessment of abdominal organs, e.g. liver
- Performing ultrasound-guided biopsies
Cardiac
- Assessment of cardiac anatomy and function, e.g. investigation of murmurs
- Investigation of episodes of ataxia/collapse
Ophthalmological
- Investigation of globe disease, e.g. cataracts, retinal detachment
Miscellaneous
- ‘Lumps and bumps’, e.g. haematoma vs. abscess
• Finding foreign bodies and sequestra
• Ultrasound-guided diagnostic and therapeutic procedures, e.g. thoracocentesis or injecting tendon core lesions
Equipment Required
Portable ultrasound systems are most suitable for ambulatory practice
Cart based or mobile ultrasound systems are more commonly used for hospital use
Probes -
- For distal limb musculoskeletal and ophthalmological purposes – a high frequency linear probe is required
- For pelvic and abdominal scanning – a low frequency convex (curvilinear) probe is needed
- Reproductive tract – rectal probe (linear)
- Cardiac – low frequency phased array (sector) probe
- ‘Lumps and bumps’ – usually high frequency linear probe, though a low frequency convex probe might sometimes be required
Pros
- Portability of equipment
- Non-invasiveness
- Low upkeep costs
Cons
- Dependent on operator skill
