Baby - Cat
Baby, a 16 year-old castrated male Domestic Shorthair presented to Southeast Veterinary Neurology with a 1-year history of ear infections. He had been treated with prednisone and Baytril otic and seemed to improve, however signs would recur. He was never off balance, but just seemed dull and reluctant to jump onto the furniture and countertops. The night prior to presentation to Southeast Veterinary Neurology, he became very lethargic and was unresponsive for about 8 hours.
The neurological examination evaluates mentation, gait and posture, postural reactions (“CP’s”), spinal reflexes and cranial nerves.
Mentation: Baby is clearly dull and distant.
Gait and posture: He is unable to stand and walk on his own. When supported to stand, he crouches low, takes a couple of steps and lays down or falls. He seems to scuff the thoracic limbs when trying to walk. He has a tendency to fall to the left, but there is no evidence of head tilt or abnormal nystagmus or strabismus.
Postural reactions: When ‘hopped’ on one leg, he does not accurately hop on any of the limbs, however, the left thoracic limb is the worst.
Spinal reflexes were normal (not shown).
Cranial nerves: Baby does not have a menace response in either eye. Palpebral reflex is normal. Remainder of cranial nerves are normal (not shown in the video).
His examination suggests a problem affecting the cerebral cortex, slightly more towards the right side.
Possible causes include a brain tumor, infection, degeneration or other less likely cause
The referral CBC, chemistry panel, T4 and urinalysis were unremarkable. Thoracic and abdominal radiographs were unremarkable. An MRI was performed.
The first image is a sagittal, T2-weighted MRI of Baby’s head. Rostral is toward the left and dorsal is toward the top of the image. The nasal cavity is on the far left. The brain is the the light grey and white area in the middle. There is a large, ovoid mass at the dorsal aspect of the brain. Note the evidence of mass effect–the brain tissue is being pushed ventrally away from the mass. The cerebellum is normally round, but you can see how it is being compressed caudally and that there is herniation (arrows) of the cerebellum through the foramen magnum. Lastly, there is evidence of fluid within the cervical spinal cord, consistent with syringomyelia. This is the white area within the spinal cord on the right side of the image. A CT scan would not show these changes.
The second image is a T1 weighted sagittal image of Baby’s head. Contrast agent has been administered. The tumor enhances with the contrast agent. Note that the tumor appears to grow from the outside and push inward on the brain. Furthermore, there is a ‘tail’ at the cranial/dorsal and caudal/dorsal aspects of the mass. This is called a ‘dural tail’ sign. While a definitive diagnosis cannot be obtained without a biopsy, the most common cause of a large, contrast-enhancing mass with broad-based dural attachment in a 16 year-old cat is a meningioma.
After discussion with the owner, brain surgery to remove the mass was elected. A craniectomy was performed. A large, tan/grey, very firm and well-adhered mass was removed. It was tightly adhered to the skull and came out en-bloc with the skull. Here is a photograph of the mass after surgery. The mass is ‘upside down’, with the skull (dorsal) at the bottom of the photo. Histopathological analysis confirmed a meningioma.
Meningioma’s tend to be very slow-growing brain tumors. They are often amenable to surgical excision. They tend to be so slow-growing that follow-up treatment is not necessary. Baby was hospitalized for 3 days after surgery for post-operative pain management, nutritional support and nursing care.
After surgery, he is more alert, is able to see and explore his surroundings. He is ambulatory with minimal ataxia and no ‘scuffing’ of his toes. We are happy to report that Baby is still doing great!