Use of a novel helical fan beam imaging system for computed tomography of the distal limb in sedated standing horses: 167 cases (2019-2020).

The study assessed the capability of a new helical fan beam CT system in diagnosing various distal limb problems in a clinical sample of 167 horses. The results demonstrated that the CT system provides a high degree of diagnostic accuracy, and can be used safely and conveniently to scan sedated standing horses.

Overview of the Study

• The researchers evaluated the use of a novel helical fan beam Computed Tomography (CT) system for diagnosing horses with distal limb problems. Distal limb problems refer to issues with the lower parts of the legs, including but not limited to feet, pastern, and fetlock regions. Data was recorded on factors such as the horse’s age, breed, presenting complaint, sedation used, and procedure time. Other details like diagnosis from imaging and other diagnostic methods used were also noted.
• The sample comprised 167 horses, majorly Thoroughbreds and Quarter Horses. The veterinarians had a clinical approach in which the CT scan was incorporated into the lameness investigations protocol.

Major Findings

• The procedure times varied between 15 to 40 minutes, and each region of interest took around 15 to 45 seconds to scan. The most frequently scanned area was the foot or pastern region (in 53% of horses), and the navicular bone disease was the most common diagnosis (in 48% of these horses). The fetlock region, another commonly scanned area (in 40% of horses), revealed a frequent diagnosis of palmar or plantar osteochondral disease (in 40% these horses).
• All horses remained compliant during these scans. No complications due to sedation or damage to the scanner were reported. This suggests that the helical fan beam CT system can be used safely on sedated horses standing still, without causing harm to them or the machinery.
• The CT imaging provided a specific diagnosis for lameness in almost all cases (99%), which was significantly higher than the conventional planar digital radiography method that only achieved a 45% success rate. This indicates the CT system’s potential in providing superior diagnosis and its valuable contribution to the domain of veterinary diagnosis.

Conclusions

• The new helical fan beam CT system was found to be not only safe and easy to use in a clinical setting, but also significantly more effective in diagnosing distal limb problems in horses compared to traditional methods. This could suggest its potential application not just in university-based veterinary hospitals, but also in broader contexts as well.
• The positive results obtained in this study advocate for the integration of CT imaging into standard lameness investigations, which could potentially improve diagnosis reliability and accuracy and as a result, enhance the efficacy of treatment strategies in equine practice.