Modified Intraglandular Sialography by US-guided Contrast Injection in Dogs

Abstract

Sialography is a useful diagnostic method in the investigation of disease involving the salivary glands and ducts. However, the disadvantages of conventional method include the need for general anesthesia and the difficulty associated with locating the duct openings. The purpose of this study was to develop a simple and reliable sialography protocol in dogs and to determine the optimal dose of contrast medium into the mandibular gland under fluoroscopy. Eight healthy dogs without salivary gland abnormalities were used. Ultrasound-guided percutaneous injection of iopromide (Ultravist 370®

SCHERING Co., Seoul, South Korea) into the left mandibular gland of all dogs was performed to determine the optimal dose and fluoroscopic imaging time. Fluoroscopic evaluation was performed from immediately before injection of iopromide until each dose was fully injected. On the fluoroscopic images, mandibular gland and entire mandibular duct were identified in five dogs (62.5%). Mandibular gland and partial duct were identified in two dogs (25%), and only mandibular gland was visualized in a dog (12.5%). Of five dogs, entire duct was identified after 7.0 ml iopromide injection in two dogs (25%), and 9.0 ml injection in three dogs (37.5%), respectively. The time from iopromide injection to the identification of mandibular duct ranged variously, from 6 to 27 seconds. Based on the results of the present study, it was recommended that the fluoroscopy of mandibular glands and ducts should be performed immediately after (at least within 6 seconds) the contrast injection of 7.0 ml or more volume of iopromide into the mandibular gland under ultrasound guidance. This simple and reliable method may be helpful to increase the detection sensitivity for abnormalities of salivary glands and guiding surgical approaches in dogs. Therefore, this technique may be an alternative technique to conventional sialography in dogs.