Use of contrast-enhanced computed tomography to assess angiogenesis in deep digital flexor tendonopathy in a horse.

This research compares the effectiveness of contrast-enhanced computed tomography (CT) scans and high field magnetic resonance (MR) imaging in diagnosing deep digital flexor tendonopathy in a horse. The study finds that CT scanning proves effective for identifying angiogenesis, the process of new blood vessels forming, which MR imaging fails to identify without using a contrast medium.

Methodology

• The study utilized both contrast-enhanced CT and high field MR imaging to diagnose deep digital flexor tendonopathy in a horse. These are methods of scanning that can show images of tissues and structures within an animal’s body.
• After identifying lesions, or abnormal tissue, in the distal extremity of the horse, the researchers documented these physically and histopathologically. This means they studied how the disease affected the tissue’s microscopic structure.

Findings

• With CT scanning, the horse’s deep digital flexor tendon lesions were found to be noticeably enhancing the contrast medium, signifying angiogenesis in the core and dorsal border lesions. Angiogenesis is the formation of new blood vessels, a process commonly seen in the healing of injuries.
• Even though MR imaging could clearly identify the shape of the lesions, without a contrast medium, it could not identify angiogenesis. This suggests that CT scanning may be superior when wanting to assess blood vessel formation in such injuries.
• Finally, the researchers turned to gross examination (looking at the larger structures of the organ without a microscope), histopathologic examination (microscopic examination of tissues), and CD31 immunohistochemistry (a staining process used to visualize certain proteins under a microscope). These confirmed the diagnosis of tendonopathy (disease of the tendon) and revealed an increase of small blood vessels, further confirming angiogenesis.

Implications

• Despite the different mechanisms of image formation, the lesions appeared similarly on both the contrast-enhanced CT and MR images. This suggests that either method could be used to gain a detailed picture of the lesions.
• However, due to its ability to identify angiogenesis without the need for a contrast medium, contrast-enhanced CT may present an alternative to MR imaging for assessing tendon and ligament injuries in horses. This method of diagnosis could also be applied to other equine injuries or diseases.