FOLLOW-UP EXAMINATIONS
Figure 2. Subgross image of the eye in cross section, stained with hematoxylin-eosin. The eye is no longer intact, with the
posterior sclera containing a full-thickness defect (asterisk). Inflammatory cells have diffusely infiltrated and accumulated
(seen as dark purple) in the vitreous cavity and in the surrounding orbital tissue.
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The dog returned to the referring veterinarian two weeks after the surgery for suture removal and recheck. The dog had recovered
well, and all medications were discontinued. A follow-up at CSU two months after the surgery showed that the dog was happy
and healthy.
HISTOLOGIC FINDINGS
Figure 3. In one area of the vitreous cavity, a small bit of plant material is seen with a dense surrounding of bacteria and
inflammatory cells immediately adjacent to it. The plant material is multichambered with a refractile cellulose wall.
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Histologic examination findings of the globe were consistent with a diagnosis of septic panophthalmitis secondary to an intraocular
plant foreign body. Hemorrhage, fibrin, and large sheets of neutrophils were present in both the anterior and posterior chambers
and the vitreous cavity. The retina, choroid, and sclera were effaced by neutrophils and variable amounts of edema and hemorrhage,
and a full-thickness defect was present in the posterior sclera (Figure 2). In the vitreous, a piece of plant material was surrounded by coccoid bacteria that, in turn, were surrounded by neutrophils
(Figure 3).
Neutrophils and smaller numbers of lymphocytes and plasma cells infiltrated the extraocular muscles and periorbital fat. The
myofibers of the affected extraocular muscles were shrunken and hypereosinophilic and had pyknotic nuclei. Moderate numbers
of neutrophils infiltrated the cornea, which was diffusely ulcerated. The posterior scleral defect was thought to be the site
of penetration of the foreign body as no other fibrous tunic defects were identified.
The final diagnosis was septic panophthalmitis due to plant foreign body penetration of the globe.
DISCUSSION
Intraorbital and intraocular foreign bodies are not uncommon in dogs1-6; however, this case of an intraocular foreign body is unusual because the plant material probably entered the eye through
the posterior sclera rather than anteriorly through the cornea. Most ocular foreign bodies in dogs enter the conjunctival
sac and are removed by increased tearing and blinking, go down the nasolacrimal puncta, or enter the orbit by migrating between
the globe and the orbital wall.1
Once in the orbit, the foreign material typically causes orbital cellulitis or abscess formation.1,2 Grass awns (foxtails) and other plant materials are the most common intraorbital foreign bodies seen in dogs, although glass
and metal (air gun pellets) objects3 and porcupine quills4 have also been reported.
Intraocular foreign bodies usually penetrate the eye directly; however, migration of objects from the orbit through the sclera
have been reported.3 One report described the case of a Kerry blue terrier that was presented for anorexia, fever, facial and throat pain, and
chemosis and episcleral congestion of the right eye.3 Oral antibiotics failed to resolve the problem. After heroic efforts to save the eye failed, enucleation was performed.
Histologic examination of the globe showed severe, destructive panophthalmitis. Plant foreign material was detected in the
globe. The presence of a posterior area of disruption in the sclera suggested that it was the most likely route by which a
grass awn had entered the eye.3
Another article reported on a series of five cases of dogs that had ocular or orbital porcupine quills.4 Two of the dogs had only orbital lesions, one had a corneal perforation that ruptured the lens capsule, one had a corneal
lesion but the quill did not reach the lens, and one had an intraocular and intraorbital quill. In the dogs with intraorbital
lesions, it was suspected that the quills entered the orbit or eye through the roof of the oral cavity.4
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