Neurologic deficits and surgical treatment in a horse affected with internal carotid artery tortuous elongation

Abstract

SummaryA 2‐year‐old Warmblood gelding was presented with a history of bilateral feed material coming from the nostrils secondary to dysphagia, coughing and impairment of physical development, since purchase at 6 months of age. Endoscopy of the right guttural pouch was unremarkable; however, in the left guttural pouch, a distended (aneurysm), pulsating, tortuous elongated internal carotid artery (ICA) was observed. Computed tomography revealed that in the dorsal aspect of the medial compartment of the left guttural pouch adjacent to the jugular foramen, the ICA turned anti‐clockwise creating a small loop of 1 cm diameter. This loop had a faint linear, soft tissue attenuating connection to the caudodorsal wall of the guttural pouch and was slightly larger in diameter compared to the right ICA. A malformation of the left ICA was diagnosed, most likely congenital. A secondary compression and neuropathy of one or multiple nerves of the associated lower cranial nerves in the neurovascular plica (IX, X) was suspected explaining the clinical signs of dysphagia. The slightly larger diameter of the left ICA could represent congestion of the vessel or an early aneurysm formation. Based on these findings, endovascular balloon occlusion (nondetachable balloon) of the left ICA was performed to relief the compression on the affected nerves. The occlusion of the ICA resolved the clinical signs within 7 weeks after surgery.