VRCCO Advances Brain Surgery Boundaries with Feline Pituitary Procedure and Welcomes New Board-Certified Neurologist

BEND, OR / ACCESS Newswire / September 23, 2026 / The Veterinary Referral Center of Central Oregon (VRCCO) continues to solidify its position as a national destination for advanced animal healthcare after successfully performing a highly intricate brain surgery on a ten-year-old feline, Mars, who traveled thousands of miles for care.

Mars’ journey for treatment highlights the exact purpose of VRCCO’s medical travel program: by providing a structured support system that transforms overwhelming long-distance logistics into a manageable reality, allowing families to focus entirely on their pet’s care.

Mars’ Journey from New Jersey for a High-Stakes Procedure
Mars, a ten-year-old cat from Hoboken, New Jersey, perfectly showcases the depth of VRCCO’s neurological and neurosurgical capabilities. Mars was diagnosed with severe, insulin-resistant diabetes mellitus and hypersomatotropism (elevated IGF-1), a condition caused by a pituitary gland tumor that secretes excess growth hormone.

To manage his condition, Mars required an unprecedented twenty units of insulin per day (compared to the typical feline dose of one to two units). Left untreated, the excess growth hormone would continue to cause irreversible damage to Mars’ heart, joints, and kidneys.

A cure to Mar’s diabetes would require a specialized procedure, a Transsphenoidal Hypophysectomy (TSH) which involves accessing the pituitary gland through the soft palate in the roof of the mouth. The pituitary gland is located at the base of the brain and surrounded by major, life-sustaining blood vessels, which leaves the surgical team with zero margin for error.

Mars’ family searched nationwide for an experienced pituitary surgical team, which led them to VRCCO’s board-certified neurologist, Dr. Annie Chen-Allen, DACVIM, alongside Dr. Tina Owen, DACVS and Dr. Linda Martin, DACVECC, two of Chen-Allen’s key collaborators on pituitary surgeries during her tenure at Washington State University. This team has completed over 30 pituitary surgeries together in dogs and cats.

To prepare for Mars’ highly delicate surgery, Dr. Chen-Allen, alongside her team, practiced the procedure extensively. They integrated a custom, 3D-printed surgical template developed by VRCCO’s CEO and surgeon, Dr. Mauricio Dujowich, DACVS, to optimize precision. Utilizing a state-of-the-art 3D magnification camera system, the team successfully navigated a tiny six-millimeter-by-three-millimeter window in the skull to excise Mars’ tumor in one piece.

“This surgery has an incredibly high learning curve and a high mortality rate historically,” said Dr. Chen-Allen. “Being able to successfully perform this micro-surgery requires an experienced team and an incredible orchestra of people. From our advanced 3D visualization technology to the round-the-clock ICU management by our critical care specialists, Mars’ success is a testament to what a highly collaborative specialty team can achieve.”

Following intensive post-operative management by VRCCO’s critical care team to regulate his electrolytes and hormones, Mars made a remarkable recovery. Just one week after surgery, his IGF-1 had returned to normal and his insulin dependency had dropped dramatically. Today, back home in New Jersey, Mars’ neurological and physical strength continue to improve. “He can finally jump again,” states his pet parent. “After losing his ability to jump earlier this year and struggling to pull himself onto the couch, he just jumped all the way up onto our tall bar stool, it is a big win!”

Watch Mars’ journey with VRCCO here.

Expanding the Neurology Team: Welcoming Dr. Elizabeth Passmore
To meet the growing regional and national need for advanced neurological care, VRCCO is also pleased to welcome board-certified veterinary neurologist Dr. Elizabeth Passmore, DVM, DACVIM-Neurology, to its medical team.

Dr. Passmore grew up in northern Virginia and graduated with honors from Carnegie Mellon University with a Bachelor of Science in Chemistry. She earned her Doctorate of Veterinary Medicine (DVM) from the University of California, Davis, in 2016. Following a rotating internship at the University of Illinois and a specialty neurology internship in Arizona, she completed a rigorous three-year neurology and neurosurgery residency in New Mexico.

Board-certified by the American College of Veterinary Internal Medicine in Neurology, Dr. Passmore founded the Neurology & Neurosurgery Service at Pet Specialists of Austin, where she served the Texas community for five years before deciding to bring her expertise to Central Oregon.

“We are thrilled to welcome Dr. Passmore to our growing team,” said Dr. Dujowich, CEO of VRCCO. “Adding a second team-oriented and brilliant board-certified neurologist to our hospital increases our capacity to perform advanced neurosurgeries, provide rapid emergency consultations, and expand life-saving treatment options like the pituitary surgery performed on Mars.”

About VRCCO

The Veterinary Referral Center of Central Oregon offers the most advanced veterinary services to members of Bend, the Central Oregon community and beyond. Their mission is to provide the highest standard of veterinary medicine by supporting their community to be their pet’s greatest advocate through access to innovative and compassionate care. VRCCO provides 24/7 emergency care and board-certified expertise in surgery, dermatology, internal medicine, neurology, ophthalmology, oncology, and anesthesiology.

Media Contact:
Katie Sedivec, Director of Brand and Marketing
Veterinary Referral Center of Central Oregon
marketing@vrcvet.com
541-209-6960
www.vrcvet.com

SOURCE: Veterinary Referral Center of Central Oregon

View the original press release on ACCESS Newswire

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