Angiographic Variation of the Internal Carotid Artery and its Branches in Horses.

This research aimed to study the anatomical differences of the Internal Carotid Artery (ICA) in horses using angiography. The study found variations in how the ICA branches off to other arteries, and these findings could help in treating guttural pouch mycosis – a fungal condition in horses.

Methodology

• The study used in-vitro methods, which means the experiments were conducted outside a living organism. In this case, the researchers examined the ICA anatomy in equine cadaver specimens.
• The sample included 50 horse specimens of various breed, age, sex, and use. Importantly, none of the horses had a history of guttural pouch disease.
• To study the ICA and its branches, researchers used two types of angiography techniques: conventional and rotational. Conventional angiography was used for seven specimens, and rotational angiography – for 43.
• The angiographic findings were validated by creating arterial latex casts, a method that helps visualize the vascular system and its complex structures.

Results

• The researchers found that the ICA anatomy could be grouped into 4 categories, based on variations in its branching.
• The first group includes cases where the internal carotid and occipital arteries arise from a common trunk. It means they come together to form one main artery.
• The second group includes specimens with an abnormal branch of the extra-cranial ICA connected to the basilar artery. This implies an unusual connection between two separate arteries.
• In the third group, an abnormal branch of the ICA disperses into the surrounding tissue and is not connected to any other vessels.
• The fourth group involves an abnormal branch of the ICA that gives rise to smaller satellite branches. These were found to be connected to the caudal branch of the ipsilateral occipital artery.

Conclusions

• The study concluded that rotational angiography is an effective technique for identifying variations in the anatomy of the ICA.
• These findings could have important implications for treating equine guttural pouch mycosis. The understanding of ICA’s variations could assist veterinarians in achieving vascular occlusion, which is critical in addressing this fungal infection.