Successful hypophysectomy in dog with Cushing’s syndrome

A dog’s Cushing’s syndrome has been resolved following a transsphenoidal hypophysectomy performed at the Hospital for Small Animals.

This challenging surgery involved veterinary neurosurgeons removing a large pituitary tumour from the base of the brain through the soft palate in the dog’s mouth. 

The Hospital is the first in Scotland and one of only five centres in the UK that has successfully performed surgery in dogs with pituitary-dependant Cushing’s syndrome. It is also one of a handful of centres in the world able to offer both radiotherapy and surgery options for cats and dogs with pituitary diseases. 

Complex case

Lordy, an eight-year-old cocker spaniel, was referred to the Hospital’s Neurology Service with multiple complex neurological problems.

Magnetic Resonance Imaging (MRI) identified a primary pituitary tumour measuring 1.2 cm in height. Blood and urine tests confirmed that the dog had Cushing’s syndrome, or hypercortisolism, due to the mass. 

Computed tomography (CT scan) a month later suggested that the tumour was increasing in size and that there was a significant risk that it would invade other local structures and potentially cause additional neurological problems. 

Due to the size and position of the tumour, after consultation with the dog's owners, the decision was made to perform a transsphenoidal hypophysectomy. The benefits of the surgical removal of the tumour and pituitary gland would remove the risk of additional neurological problems and provide control of the dog’s Cushing’s syndrome. 

Specialist surgery

Transsphenoidal hypophysectomy is a technically challenging surgery. In preparation, a 3D-printed model was produced using CT images, which fitted into the roof of the dog’s mouth to help guide drill location and trajectory. A 5mm hole was burred through the base of the skull, allowing access and removal of the pituitary mass.

During and immediately after the surgery, Lordy was under the watchful eye of the Hospital’s Anaesthesia and Emergency and Critical Care Services who ensured a safe and controlled recovery from surgery.

Positive outcome 

Lordy recovered quickly following surgery and was discharged three days later. Follow-up MRI scans at three and six months showed no sign of the tumour or damage to brain tissues. Lordy remains a regular visitor to the Hospital’s Internal Medicine Service, for continued monitoring and care.