Cardiac Disease Related to Primary Hyperthyroidism in a 20-Year-Old Mule.

Primary hyperthyroidism is a rarely diagnosed endocrinopathy in equids and there have been no previous reports of structural and functional cardiac changes associated with hyperthyroidism in these species. This case report investigates a 20-year-old mule gelding that presented for a three-month history of thin body condition despite polyphagia, with a heart murmur and elevated free and total thyroid hormone concentrations. On presentation, physical exam revealed a body condition score of two out of nine, persistent tachycardia, pansystolic heart murmur and firm bilateral ventral proximal cervical masses. Bloodwork confirmed markedly elevated free T4, total T4 and T3 concentrations. Echocardiogram demonstrated left ventricular concentric hypertrophy with increased ventricular and atrial systolic function. Bilateral thyroidectomy was performed under standing sedation without complications. Histopathology demonstrated adenocarcinoma of the left thyroid gland and multiple adenomas with osseous metaplasia within the right thyroid. The mule was supplemented with levothyroxine sodium two weeks post-op after a thyroid panel demonstrated undetectable concentrations. Polyphagia resolved following surgery and the mule began gaining weight. Echocardiographic changes improved but did not resolve at two years post-operative. Continued bi-annual follow up and monitoring of thyroid levels was recommended. This case represents the first documentation of hemodynamically relevant cardiac remodeling in an equid associated with primary hyperthyroidism.

Resolution of chronic regurgitation in an 8 month old Babydoll sheep by thoracoscopic treatment of a vascular ring anomaly.

OBJECTIVE: The objective was to describe the successful thoracoscopic treatment of esophageal entrapment resulting from a vascular ring anomaly (VRA) comprising a persistent right aortic arch (PRAA) and left ligamentum arteriosum (LA) in a Babydoll sheep wether. STUDY DESIGN: Case report. ANIMAL: Eight month old Babydoll sheep wether, 13 kg. METHODS: The patient presented with a weight half that of its sibling, persistent regurgitation following eating, and delayed growth noted from the age of approximately 2 months, coinciding with the introduction of solid feed into the diet. Plain thoracic radiographs were within normal limits but computed tomography angiography (CTA) confirmed multiple congenital vascular anomalies. The primary finding was esophageal and tracheal entrapment by a PRAA and left LA. Thoracoscopic transection of the LA was performed with a bipolar vessel sealing device with the aid of transesophageal endoscopy. RESULTS: Immediate improvement in attitude and absence of regurgitation were observed. The patient was discharged and subsequently reintroduced to grazing and long-stem hay, which were previously not tolerated. By 6 months post discharge, the patient's weight was 36 kg, comparable to an age-matched sibling and considered appropriate for the stage of growth. CONCLUSION: Thoracoscopic transection of the LA in sheep is a feasible treatment for esophageal compression resulting from a VRA. Surgical intervention resolved the clinical signs and allowed normal digestive rumination, restoring bidirectional esophageal function in a ruminant.

Transnasal, Endoscopically Guided Skull-Based Surgery by Pharyngotomy for Mass Removal from the Sphenopalatine Sinus in a Horse.

OBJECTIVE: To report a transnasal, endoscopically guided ventral surgical approach for accessing the cranial and caudal segments of the sphenopalatine sinus for mass removal in a horse. STUDY DESIGN: Case report. ANIMAL: Adult horse with acute onset blindness referable to a soft tissue mass within the sphenopalatine sinus. CLINICAL REPORT: A 7-year-old Warmblood gelding presented with a history of running into a fence and falling. No neurologic signs were identified at initial examination but acute blindness was noted 3 weeks later. On computed tomography (CT) the sphenopalatine sinus was filled with a large homogeneous mass with poor contrast enhancement that extended dorsally with thinning to the dorsal cortex of the sphenoid bone, just rostral to the entrance of the optic canals into the cranial cavity. Surgical access to the sphenopalatine sinus was achieved using a transnasal, endoscopically guided ventral pharyngotomy approach and the mass lesion was removed. A presumptive diagnosis of chondroma was made based on histopathology. The horse recovered well from surgery, and although it has not regained vision as of 6.5 years postoperatively, the disease has not progressed. CONCLUSION: Transnasal, endoscopically-guided ventral surgical access to the sphenopalatine sinus is possible in horses and may improve access in horses with disease extending caudally beyond the palatine portion of the sinus. Use of smaller diameter or specialized instruments, such as various endoscopic bone cutting instruments, and CT image guidance may improve sinus access by this route.