Congenital anterior staphyloma associated with Peters’ anomaly and aphakia in a Holstein calf

Abstract

A Holstein calf was born with a large protruding right eye and a central corneal opacity. Enucleation was the first choice of treatment. The calf had a good prognosis and was raised for milking purposes. Macroscopically, the enucleated eye was characterized by the protruded cornea, adherence of the iris to the central posterior cornea and aphakia. Microscopically, central corneal thickening and a defect in the endothelium and Descemet’s membrane were observed. These data suggest that this represents a case of unilateral anterior segment dysgenesis consistent with congenital corneal staphyloma with Peters’ anomaly and aphakia. Neither a mutation of the WFDC1 gene in multiple ocular defects nor any other identifiable cause for ocular anomalies was detected.

Case Report: Ultrasonography and Magnetic Resonance Imaging of Anterior Segment Dysgenesis in a Calf

“…In the early embryonic eye, complete separation of the lens vesicle from the surface ectoderm, which is the origin of the corneal epithelium and lens vesicle, triggers the migration of mesodermal tissue; this follows the formation of the corneal stroma, corneal endothelium, papillary membrane, ciliary body, and trabecular meshwork (2,17,19). Incomplete separation can result in structural adhesion between the cornea and the lens, leading to the complete or incomplete absence of the lens (referred to as "aphakia" and "microphakia", respectively) at birth (2,3,19). In cases of bovine microphakia, a rudimentary lens, part of the lens capsule, and a dysplastic lens are commonly embedded within the sclera, the cornea, or the anterior uvea (3,20).…”

“…Incomplete separation can result in structural adhesion between the cornea and the lens, leading to the complete or incomplete absence of the lens (referred to as "aphakia" and "microphakia", respectively) at birth (2,3,19). In cases of bovine microphakia, a rudimentary lens, part of the lens capsule, and a dysplastic lens are commonly embedded within the sclera, the cornea, or the anterior uvea (3,20). In addition, the abnormal migration of mesodermal tissues subsequent to the incomplete separation of the lens vesicle possibly contributes to malformation of the anterior segment of the eye, including the ciliary body and the iris (21).…”

“…Anterior segment dysgenesis (ASD) is a rare congenital ocular disease, which occurs as a result of the abnormal maturation of neuro-ectodermal cells during the organogenetic period of the eye (1). ASD is a common cause of unilateral or bilateral exophthalmos (2)(3)(4). Besides an ASD, multiple bovine diseases associated with involvements of exophthalmos are previously reported, including systemic or local infections of Moraxella spp.…”

Ocular hamartoma in a five‐day‐old calf

“…In human and animals, lesions related to ASD include a wide variety of intraocular defects that impair vision 11 . ASD is rarely reported in cattle, 11 and complications from ASD result in enlargement of the affected eye 12, 13 . ASD results in an enlarged orbit due to an intraorbital deformity, whereas a hamartoma results in an abnormal eye mass, consisting of mature cells.…”

Bilateral anterior segment dysgenesis with the presumed Peters’ anomaly in a cat

“…Anterior segment dysgenesis (ASD) has been reported sporadically in different species of animals, including dogs, cats, cattle, horses, mice and wild animals, etc [ 1 , 3 , 6 , 11 , 14 , 15 ]. The ASD is a general term to describe a heterogenous spectrum of developmental disorders affecting the cornea, iris, lens, and iridocorneal angle structure [ 2 , 13 ].…”