Intracranial meningioma causing internal ophthalmoparesis in a dog

Clinical signs, imaging findings, and outcome in twelve cats with internal ophthalmoparesis/ophthalmoplegia

OBJECTIVE

To retrospectively evaluate the clinical signs, imaging findings, and outcome of feline internal ophthalmoparesis/ophthalmoplegia.

PROCEDURE

Medical records were reviewed from 2008 to 2015. Inclusion criteria included cats that presented with internal ophthalmoparesis/ophthalmoplegia, underwent diagnostic imaging, and had follow-up information available.

RESULTS

Twelve cases of feline internal ophthalmoparesis/ophthalmoplegia were identified. Nine cats were unilaterally affected, and three cats were bilaterally affected. Affected cats had a median age of 10.54 years (range 5.75 to 13.17), and both sexes of varying breeds were affected (nine males; three females). Clinical signs including abnormal mental status (n = 9; 75%) and additional neurologic abnormalities (n = 10; 83%) were observed. Magnetic resonance imaging and/or computed tomography (MRI/CT) of the head were performed in ten cats, revealing a mass lesion in all cases with varying locations. Multicentric lymphoma was diagnosed in two cats via abdominal ultrasound and cytology. All twelve cats were euthanized due to deterioration of clinical signs and/or quality-of-life concerns. Median time from diagnosis to euthanasia was 3.5 days (range 0 to 80 days).

CONCLUSIONS

Feline internal ophthalmoparesis/ophthalmoplegia rarely presents as the sole clinical sign in a referral hospital. Advanced imaging (MRI/CT) may be necessary to reach a definitive diagnosis in these cases. However, abdominal ultrasound would be advocated in cats with systemic clinical signs as a less expensive and less invasive diagnostic test to further investigate the possible etiology of internal ophthalmoparesis/ophthalmoplegia prior to advanced imaging. Feline cases with internal ophthalmoparesis/ophthalmoplegia associated with other intracranial signs and/or systemic clinical signs have a poor prognosis.

Mydriasis associated with local dysfunction of parasympathetic nerves in two dogs

In clinical practice, photophobia resulting from persistent mydriasis may be associated with dysfunction of ocular parasympathetic nerves or primary iris lesions. We encountered a 5-year-old Miniature Dachshund and a 7-year-old Shih Tzu with mydriasis, abnormal pupillary light reflexes, and photophobia. Except for sustained mydriasis and photophobia, no abnormalities were detected on general physical examination or ocular examination of either dog. We performed pharmacological examinations using 0.1% and 2% pilocarpine to evaluate and diagnose parasympathetic denervation of the affected pupillary sphincter muscles. On the basis of the results, we diagnosed a pupillary abnormality due to parasympathetic dysfunction and not to overt primary iris lesions. The test revealed that neuroanatomic localization of the lesion was postciliary ganglionic in the first dog.