J Vet Sci.  2018 Nov;19(6):835-839. 10.4142/jvs.2018.19.6.835.

Comparison of two techniques for transpharyngeal endoscopic auditory tube diverticulotomy in the horse

• Koch DW
• Easley JT
• Nelson BB
• Delcambre
• McCready E
• Hackett ES

• KMID: 2427032
• DOI: http://doi.org/10.4142/jvs.2018.19.6.835

Abstract

Auditory tube diverticula, also known as guttural pouches, are naturally occurring dilations of the auditory tube in horses that communicate with the nasopharynx through a small ostium. Infection and select other conditions can result in inflammation and narrowing of the nasopharyngeal ostium, which prevents drainage of fluid or egress of air and can lead to persistent infection or guttural pouch tympany. Auditory tube diverticulotomy allows continuous egress from the auditory tube diverticula and is a feature of disease treatment in horses, in which medical treatment alone is not successful. Transpharyngeal endoscopic auditory tube diverticulotomy was performed using a diode laser either at a single dorsal pharyngeal recess location or bilaterally caudal to the nasopharyngeal ostium in 10 horse head specimens. Both methods resulted in clear communication between the nasopharynx and auditory tube diverticula. Diverticulotomy performed in the dorsal pharyngeal recess required less laser energy and activation time and had a shorter surgical duration than diverticulotomy performed caudal to the nasopharyngeal ostium. Further study related to the clinical application of both techniques is warranted.

Keyword

diode lasers; empyema; endoscopic surgical procedure; laser surgery; veterinary surgery

MeSH Terms

Diverticulum
Drainage
Empyema
Endoscopy
Eustachian Tube*
Head
Horses*
Inflammation
Laser Therapy
Lasers, Semiconductor
Nasopharynx
Surgery, Veterinary

Figure

• 

  Fig. 1 Illustration of the equine nasopharynx. Incision areas for auditory tube diverticulotomy within the dorsal pharyngeal recess (DR) and caudal to the nasopharyngeal ostium (CNO) have been indicated by a red rectangle bordering the DR site and blue triangles bordering the CNO sites.

• 

  Fig. 2 Computed tomographic images (transverse plane [A] and dorsal plane [B]; 2 mm standard window) of a horse head specimen following auditory tube diverticulotomy within the dorsal pharyngeal recess. Note communication between the nasopharynx and both left and right auditory tube diverticula (white arrows). The median septum is visible (black arrow).

• 

  Fig. 3 Computed tomographic image (transverse plane [A] and dorsal plane [B]; 2 mm standard window) of a horse head specimen following auditory tube diverticulotomy caudal to the nasopharyngeal ostium. Note communication between the nasopharynx and both left and right auditory tube diverticula (white arrows). The median septum is visible (black arrow).

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