For many years, the mainstay of treating pituitary pars intermedia dysfunction (PPID, or equine Cushing’s disease) involved administering daily doses of the medication pergolide. But could there be another option ahead? Researchers from Europe recently described a novel—and still experimental—surgical procedure designed to treat PPID with positive results.

Equine Cushing’s disease is a disorder of the pituitary gland’s pars intermedia caused by an adenoma (a type of tumor). Classic signs, most frequently seen in older horses, include an abnormal hair coat, loss of muscle tone, altered fat deposition, and chronic laminitis.

In humans with Cushing’s disease (a related, but ultimately different condition), surgical pituitary growth removal is the treatment of choice; however, none of the currently employed surgical approaches used in humans would be feasible in the horse. Removing a horse’s tumor with those methods would require drilling through several centimeters of bone and using long, slender equipment to reach it—tools that don’t currently exist.

“In other words, none of the surgical procedures in human medicine permit adequate access to the pituitary gland in horses,” explained Aimée Sakes, MSc, from the BioMechanical Engineering Department of Delft University of Technology, in the Netherlands.

As such, Sakes and colleagues got creative to develop a new technique for performing surgery in horses with equine Cushing’s: an endovascular—or intravenous—surgical approach.

As it turns out, horses are lucky to have a unique connection between the