Evisceration as an Alternative to Enucleation in Four Pet Psittacine Birds.

Abstract

In cases in which vision cannot be restored and the eye is a source of pain, removal of the eye may be indicated. In mammals, enucleation is the most common procedure performed; however, due to the distinct anatomical features of the avian eye, evisceration may be the preferred method in these species. The large globe size and rigid sclera leave the bird with a large sunken eye socket, which may cause the bird to become unbalanced and is not cosmetically appealing. Furthermore, birds have short optic nerves that can be injured due to traction and a thin interorbital septum that can be damaged during surgery. Evisceration reduces these risks and is typically done within a shorter anesthetic time. This case series reports the successful use of a modified evisceration technique in 4 pet psittacine birds: a red-tailed black cockatoo (Calyptorhynchus banksia) diagnosed with severe fungal keratitis and anterior uveitis based on histopathology, a galah (Eolophus roseicapilla) with a traumatic injury resulting in a ruptured globe, a cockatiel (Nymphicus hollandicus) diagnosed with a cataract and secondary glaucoma, and a green cheek conure (Pyrrhura molinae) diagnosed with anterior lens luxation and suspected endophthalmitis. Each bird underwent a modified evisceration surgery because the eyes were nonvisual and painful and had a grave prognosis for recovery. All 4 birds recovered uneventfully without complications and have remained stable for between 2.5 and 4.5 years postoperatively. This report demonstrates that the modified evisceration technique is safe and achievable in psittacine patients.