Case Study: “The Case of the Tongue-Tied Friesian”
Presentation:
A two year-old, Friesian stallion is presented to the hospital with a history of “frothy mouth,” “feed and slobber” coming from the mouth, and not eating hay (he would eat his grain, according to the owner). The stallion is in excellent physical condition, and has no prior medical or surgical history.
Clinical Examination:
The stallion is examined, carefully, and has normal vital signs. He does appear to be hyper-salivating, and has feed encrusted around the mouth and nostrils.
Differential Diagnoses:
1. Dysphagia (“trouble eating”)
2. Esophageal obstruction (“choke”);
3. Loose “caps” on molars;
4. Oral foreign body.
Diagnostics:
Because choke is suspected, the horse is sedated and a nasal gastric tube is passed through the esophagus. The tube passed all the way into the stomach, effortlessly.
In the interest of thoroughness, a full mouth speculum is applied, and the oral mucosa is inspected. A length of thin, dark metal approximately 4 cm long and 1 mm wide is viewed puncturing the roof of the mouth axial to the upper right dental arcade. The wire is easily dislodged, as it is not deeply embedded.
Because it is a small fragment, and because it does not, in our opinion explain the full extent of clinical sign, we decide to radiograph the skull to rule-out more fragments of what appears to be some kind of rusty wire.
A dorso-ventral radiograph of the skull reveals a dense opacity of similar dimensions to the first in approximately the same area on the opposite side. A lateral projection, however, confirms that this foreign object is actually embedded in a soft tissue structure between the lower arcades about even with the first molar on the lower left side.
Gross examination reveals a callous formation and roughening on the left lateral aspect of the tongue in approximately the same location as the opacity in the radiograph. No foreign object is observed or palpated.
Ultrasound is employed to locate the object which we now feel is embedded in the tongue. A linear, hyperechoic object surrounded by slightly less hyperechoic, granular-appearing tissue is observed inside the callous area on the tongue. The object is presumed to be the foreign body, and it is nestled in sagittal plane approximately 1 cm deep.
Treatment:
The patient is induced for general anesthesia and placed in right lateral recumbency (laying on his right side) for surgical exploration of the tongue.
With the patient under general anesthesia, the left lateral surface of the tongue is examined, and a small, partially healed puncture site is discovered. Curved, 4” Crile hemostat forceps are placed into the puncture site, and, using ultrasonographic guidance, the hemostats are directed to the object. The object is clamped with the hemostats, and withdrawn through the puncture site.
The incision is closed using 2-0 Monocryl in a simple, interrupted pattern.
The patient is placed on procaine penicillin for seven days, and the mouth is rinsed twice daily with dilute chlorhexidine.
Outcome and Discussion:
Esophageal obstruction is a common acute disorder of horses that occurs when a bolus of feed or other ingesta lodges at a point of constriction in the esophagus. There are two points of constriction in a normal esophagus: The thoracic inlet at the base of the neck and just cranial to the diaphragm before the esophagus enters the stomach at the cardiac sphincter. Choke occurs when horses “wolf” their feed (swallow large amounts of poorly chewed feed or hay), when they have esophageal disease such as stricture (a scar from a previous choke or from a puncture due to the passage of a nasal gastric tube or some other object through the esophagus); or when they have a diverticulum (a blind-ended pouch that is either acquired or developed.
Choke is suspected anytime a horse is seen hypersalivating (“slobbering”) with feed and/or water coming through the nostrils.
Choke is confirmed by the inability of the veterinarian to pass a nasogastric tube all the way into the stomach. Once confirmed, treatment involves heavy tranquilization and possibly lavage or even endoscopic assistance. Rarely, surgical intervention is required.
Choke is prevented by sound management practices including feeding horses separately, ensuring that horses have good dentition (dental examinations at least twice yearly), and slowing the consumption of feed by laying large rocks in the feed trough to make the horse “search” for the feed.
Loose “caps” occur in all horses as they loose their primary molars usually between years 2-4. These are the temporary “baby” teeth that are shed as the permanent molars erupt. Occasionally, these “caps” may cause irritation and even pain evidenced by hypersalivation or feed falling out of the mouth.
Foreign bodies in the mouth occur when a horse ingests wire, thorns, splinters, or other sharp objects which then become embedded in the soft tissue structures of the mouth: Notably the tongue or the soft palate (the “roof” of the mouth).
Outcome:
The patient recovers well from surgery and is returned to the farm within 24 hours. He is eating well, and shows none of the presenting signs after several days.
The owner discovered that large tractor tires on his farm were being used in which to feed the horses. Some of these tires were steel-belted, and one of the tires was shedding some of the steel fibers into the feed.
The tires were removed from service.
Foreign body should be suspected in any form of dysphagia (trouble eating), and a thorough oral examination performed. This case underlines the importance and ease of using dual imaging modalities to diagnose and treat the cause.
