Management of a unilateral non‐healing corneal ulcer and uveitis in a laughing kookaburra ( Dacelo novaeguineae )

Application of a modified nictitating membrane flap in a fledgling feral pigeon (Columba livia domestica) with bullous keratopathy

A fledgling feral pigeon with systemic protozoal infection was referred with corneal protrusion in the right eye after being treated for a corneal ulcer for 12 days. Ophthalmic examination revealed a corneal bulla covering almost the entire central cornea and preventing the eyelids from closing. Gelatinous corneal stroma with numerous heterophils surrounding the corneal bulla was also detected on cytologic examination. Bullous keratopathy and melting keratitis in the right eye were diagnosed. Temporary tarsorrhaphy with topical eye drops was prescribed for a week; however, the bulla persisted. A modified nictitating membrane flap was created under general anesthesia and maintained for 2 weeks. The corneal bulla resolved, and corneal thickness was restored. The pigeon was presented again with recurrence of the corneal bulla in the right eye after 45 days. Alternative surgical options were recommended; however, the pigeon was euthanized because the protozoa-induced intra-oral and intra-aural masses caused malformation of the beaks, which made voluntary feeding impossible.

Management of corneal epithelial defects in a population of mature chuck-will's-widows (Antrostomus carolinensis) in South Florida

PURPOSE

To describe ocular clinical findings, gross/histopathologic findings, and treatment regimens in a series of migratory chuck-will's-widows (Antrostomus carolinensis) (CWW) with corneal epithelial defects.

METHODS

Seven CWW were presented to the South Florida Wildlife Center (SFWC). Four presented with bilateral (OU) corneal ulceration; two developed corneal ulceration OU; one had no ocular lesions. Treatment protocols for patients with corneal ulcers included the following: medical therapy only or medical therapy combined with an additional procedure. Four patients including the bird with no ocular lesions were euthanized, and one patient died. Their globes were submitted for histopathology. Two patients were released.

RESULTS

Clinical findings prior to enucleation included superficial corneal ulceration with redundant epithelium persisting weeks to >1 month. On histopathology, epithelium in nonulcerated globes was remarkably thin; this was considered normal. Common histopathologic findings of ulcerated globes revealed epithelial and conjunctival attenuation with an acellular superficial stromal layer and hypercellular mid-stromal layer. One globe healed with medical therapy and cotton tip applicator debridement. Four globes healed by combination of medical therapy, equine amnion, nictitating membrane (NM) flap, and temporary tarsorrhaphy. No globes healed with diamond burr debridement or grid keratotomy.

CONCLUSIONS

Factors that may be contributing to these corneal epithelial defects include, but are not limited to, normally thin epithelium, exposure keratopathy, neurotrophic disease, epithelial turnover and inadequate stem cell recruitment, inherited/genetic causes, and unidentified infectious agents (eg, viral etiologies). Of the 12 eyes treated, one healed with medical therapy/cotton tip applicator debridement, and four healed with medical therapy/equine amnion/nictitating membrane flap/temporary tarsorrhaphy.