Parotid duct sialolithiasis in three Caspian miniature horses

Three Caspian miniature horses, exhibiting facial swellings, were examined in Alborz province. Physical examinations denoted sialolithiasis in two patients, and arose suspicion of the same condition in the third patient. The sialoliths were removed using a transcutaneous surgical approach with standing sedation using xylazine (1 mg/kg, intravenously) and local anaesthesia with lidocaine (5-10 mL) in all three patients. In Case 1, multiple pieces of stone were excised from the left parotid duct using a transcutaneous approach. In Case 2, a single oval-shaped stone (44 g) was excised from the right parotid duct with the same technique as mentioned above. Case 3 presented a 1-g amorphous stone partially obstructing the right parotid duct, resulting in cyst formation on the right aspect of the face. Chemical analysis identified calcium carbonate as the primary component. Given the distribution of horses in Iran, accurate estimation of the frequency of sialolithiasis is quite challenging, and numerous cases are overlooked.