Pop goes the Eyeball: Proptosis & Enucleation
Written by: Emily Klatzer • 2022 Scholar
History
Maggie is a 3 year old female Pekingese that was attacked by her housemate. As a result of the fight, proptosis of Maggie’s left eye occurred. No other injuries were noted. Approximately 3 weeks before the current incident, the housemate had caused proptosis of Maggie’s right eye. The right eye was able to be replaced rather than removed.
Pathogenesis
Proptosis describes an ocular condition where the globe is displaced abnormally. Often proptosis is the result of trauma. Since brachycephalic breeds have shallow orbits, these dogs are the most predisposed to this condition.
Diagnosis
Maggie’s right eye presented with a protruding globe and ruptured extraocular muscles. No palpebral, menace, or pupillary light reflex was observed in the damaged eye. Further diagnostics were unnecessary. However, bloodwork was done to ensure that Maggie had normal organ function and was therefore safe for anesthesia.
Treatment
Treatment of a proptosis greatly depends on the severity. Temporary tarsorrhaphy involves leaving the eye in the socket and suturing the eyelids closed over the top. This is the treatment chosen for an eye with most of the extraocular muscles intact, an intact globe, or a constricted pupil. Conversely, enucleation involves removal of an eye followed by suturing the eyelids together. Enucleation is reserved for an eye where most of the extraocular muscles are ruptured, a ruptured globe, a dilated pupil, or if there is any necrotic or infected tissue. In Maggie’s case, enucleation was elected because the extraocular muscles were damaged beyond repair.
The various approaches to enucleation include transconjunctival, transpalpebral, or lateral. Transconjunctival is a common approach that helps minimize orbital tissue loss and intraoperative bleeding. For infectious conditions, transpalpebral is often the preferred technique since the transconjunctival approach could allow for contamination into the orbit. Transpalpebral is also utilized for neoplasia or a ruptured globe. Lastly, a lateral approach may be chosen to allow improved visualization of retrobulbar tissue or increased retention of orbital tissue. Since Maggie’s eye did not have an infection or neoplasia, the transconjunctival approach was chosen.
Prognosis
Possible postoperative complications for enucleation include bleeding, infection, dehiscence, swelling, orbital emphysema, or cyst formation. The overall outlook for Maggie is positive. Companion animals can adapt to life with one eye, although depth perception will be altered. Usually, the orbital depression will become more cosmetically acceptable as the hair regrows.
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