Week 1 @ Brown Equine Hospital in Somerset, PA

Welcome readers to the 2014 Equine Summer Fellows blogging experience.  In my first week in Somerset, PA at Brown Equine Hospital (BEH) I have already seen and learned so much, and I cannot wait to see what procedures and cases my colleagues and I get to experience this summer.

This first week has been a long one, but I have been quickly reminded that working in equine medicine is exactly where I want to be.  Brown Equine Hospital is a full service hospital offering a plethora of diagnostic tools and surgical procedures.  Dr. Keith Brown is a board certified equine surgeon, and his wife, Dr. Jen Brown, specializes in equine reproduction.  Appointments of all kinds are held during normal business hours, but the clinic also offers 24/7 emergency services so there will be many late nights and tremendous learning opportunities for me this summer.  The variety of interesting cases is seemingly endless and Doctors Jen and Keith Brown, as well as BEH Intern Dr. Younkin and the BEH technicians are a wealth of information. 

I have seen a variety of procedures this week including castrations, numerous joint injections, treatment of laminitic horses, a colic work up a with medical management, and repair of a P1 (phalanx) fracture. However, the “procedure of the week” definitely had to be the ventriculocordectomy surgery (VC), of which we did 3 on Tuesday and 7 on Friday!  Horses that receive this procedure are affected by a recurrent laryngeal neuropathy called laryngeal hemiplegia.  Typically, the left side is affected, but the conditional can affect both sides to varying extents.  The recurrent laryngeal nerve innervates the dorsal cricoarytenoid muscles of the larynx, which are responsible for opening the airway while breathing. When this nerve no longer works properly, the larynx cannot open fully and can cause trouble breathing. The impact on the horse depends on the severity of the neuropathy and their intended use due to the exercise intolerance that develops.  In addition to the exercise intolerance and difficulty breathing, this condition can also cause a “roaring” noise when the horse exercises, which is a big problem for horses in many competitive fields since noise making often leads to deducted points and low placings. 

While there are several procedures that can utilized to treat laryngeal hemiplegia, the VC procedure employed by Dr. Keith Brown is a method that not only opens up the larynx allowing better air flow, but also decreases or eliminates the roaring noises associated with laryngeal hemiplegia.  During a VC, an incision is made along the underside of the horse’s neck, in the throatlatch region (just behind the larynyx).  Dr. Brown then goes through a membrane between two of the cartilages of the larynx to gain access to the inside of the airway and the majority of the procedure is visualized by an endoscope passed through the nose to the anterior aspect of the larynx.  He then removes the mucosa of the lateral ventricles and the vocal cords, which will heal with scar tissue and form a “stiffer” structure that limits collapse of the arytenoid cartilage. The surgery increases airway diameter and allows the horse to breath more easily. 

My apologies for not including any pictures with this post, but if you would like more information on laryngeal hemiplegia and the anatomy of the larynx, MSU CVM has some great information at this site: http://cvm.msu.edu/research/research-labs/equine-pulmonary-laboratory/respiratory-diseases/laryngeal-hemiplegia

In the future I will post more pictures.  Until next week, everyone!