Alterations in equine guttural pouch morphology with head position: observations using a new technique for producing accurate casts.

The research article describes an improved, simplified, and cost-effective technique for preparing precise models of a horse’s guttural pouch and observes how the shape of the pouch changes with the movement of the horse’s head.

Improved Technique for Preparing Guttural Pouch Casts

• The study introduces an advanced method for creating anatomical models of a horse’s guttural pouch. The guttural pouch is a large air-filled space in the horse’s head that’s essential for tempered regulation of the brain and inner ear.
• The new method simplified the process and is inexpensive compared to previous techniques. It produces highly accurate, durable, and flexible models.
• Silicone rubber bathtub caulk was used as the casting material. The silicone was injected into the guttural pouches of horse cadavers and allowed to cure overnight. Subsequently, the cast was carefully removed by dissection.

Observation of Guttural Pouch Morphology Changes with Head Position

• The researchers also used the new casting technique to study the effect of a horse’s head position on the shape of its guttural pouch.
• The research found substantial sectional changes in size and shape of the lateral compartment of the guttural pouch when the atlanto-occipital joint, the connection between the skull and spine, was flexed.
• The ventral border of the pouch inclined more and the depth of the impression made by the front part of the stylohyoid bone, a bone extending from the skull’s temporal bone towards the hyoid apparatus, increased with this flexion.
• Additionally, the thickness of the lateral compartment at the front decreased in the models made from flexed animals.

Conclusion

• The viscous silicone caulk led to the creation of superior casts of the equine guttural pouch.
• The observations on the changes in the pouch shape with head position concurred with earlier reports of difficulty in draining the horse’s lateral guttural pouch in a flexed head position.