Type II Peter's anomaly with histopathological proof: a case report

Abstract

Background: Peter's anomaly is a rare congenital anterior segment dysgenesis with poor visual results. This case report describes a case of bilateral Type II Peter's anomaly with notable clinical and histopathological features.

Case presentation: A 7-year-old boy was admitted to our center with complaints of bilateral central opacification, photophobia and severe reduced vision since birth. He underwent phacoemulsification, intraocular lens (IOL) implantation and anterior vitrectomy on the right eye in another medical institution two years ago. Slit lamp examination revealed bilateral central corneal opacity, few strands of peripheral iris, irregular pupils and cloudy lens with central adhesion to posterior corneal surface in the left eye. Additionally, a history of premature birth and mental retardation was also noted. The patient was diagnosed with Peter's anomaly in the left eye, pseudophakia in the right eye and bilateral amblyopia. Similar surgery to the right one was performed on the left eye. A vesicle-like structure was found in the anterior chamber intraoperatively, which was composed mainly of immature lens and some corneal stroma as revealed by postoperative histopathological examinations.

Conclusions: The exact mechanism of Peter's anomaly is not completely understood, however, the notable histopathological features of tissue obtained from the present case may provide evidence to the hypothesis of developmental anomalies.

Keywords: Amblyopia; Congenital cataract; Corneal leukoma; Corneolenticular adhesion; Histopathology; Peter’s anomaly.

Fig. 1

Intraoperative findings of the left eye. a The central corneal opacity with the cloudy, irregular lens attached to the central aspect of the posterior cornea. b The white, translucent, vesicle-like structure with the central milky opaque patch which closely stuck to the posterior cornea appeared after the phacoemulsification of partial peripheral cortex

Fig. 2

Hematoxylin-Eosin staining of the vesicle-like structure separated from lens. a The fibrous tissue with fibroblasts, proliferated collagenous fiber, scattered epithelial-like (arrow), broken and degenerated lens cortex accompanied by calcification (*) in the central focal region, and absent Descemet membrane and lens capsule. (Hematoxylin-Eosin stain, original magnification ×10). b The cubical epithelial-like cells (arrow). (Hematoxylin-Eosin stain, original magnification ×40)

Fig. 3

Histological photographs of the vesicle-like structure from lens. a Descemet membrane and lens capsule was absent in this structure. (Periodic Acid-Schiff stain, original magnification ×5). b The scattered, distributed, epithelial-like cells (arrow) stained positively for cytokeratins. (Immunohistochemical stain for cytokeratins, original magnification ×40). c The scattered, distributed, epithelial-like cells (arrow) stained positively for S-100 protein. (Immunohistochemical stain for S-100 protein, original magnification ×40). d The scattered, distributed, epithelial-like cells (arrow) stained positively for vimentin. (Immunohistochemical stain for vimentin, original magnification ×40). e The lens fibers with intense positive immunoreactivity for alpha-crystallin. (Immunohistochemical stain for alpha- crystallin, original magnification ×40). f The scattered, distributed, epithelial-like cells (arrow) stained positively for alpha-crystallin. (Immunohistochemical stain for alpha-crystallin, original magnification ×40)