From the Department of Ophthalmology, General Hospital, School of Medicine, University of São Paulo, São Paulo, Brazil.
The authors have no financial or proprietary interest in the materials presented herein.
Address correspondence to Patrícia Lunardelli, MD, Av. Marcos Penteado de Ulhôa Rodrigues, 3800, 42C, Tamboré–Santana de Parnaíba, São Paulo, Brazil CEP 06543-001.
Staphyloma in the anterior segment of the eye is a rare congenital anomaly. This developmental abnormality is characterized by corneal opacity and bulging of the cornea through the eyelids.1,2
The anterior segment of the eye in affected patients is abnormal. Common characteristics in all cases include protrusion of an opaque cornea as a whole or in the central portion, complete or partial absence of the Bowman and Descemet membranes, and complete or partial adherence of the iris to the posterior portion of the cornea. These alterations are also found in secondary anterior staphyloma, making the diagnosis difficult.1 This report describes a case of congenital anterior staphyloma that was surgically corrected with a corneal transplant.
A 1-year-old girl presented with a visible bulge in the left eyeball. The patient’s mother noticed that the left eye was different in size and was constantly accumulating secretion compared with the right eye (Fig. 1).
Figure 1. Initial Aspect of a Patient with Congenital Anterior Staphyloma.
The patient’s mother was healthy, had received prenatal medical care, and had no history of infection during pregnancy. The patient was delivered by uncomplicated cesarean section and had no family history of neurologic disease, ophthalmologic illness, or congenital malformation.
Eye examination showed a normal right eye with estimated visual acuity of 20/30. Visual acuity in the left eye was no light perception. Biomicroscopy showed total opacity of the cornea, with thinning in the center and near the edge. Intraocular pressure was 10 mm Hg in the right eye, but it was impossible to assess intra-ocular pressure in the left eye. Results of funduscopic examination of the right eye were normal.
Computed tomography showed a bulge in the anterior segment and a normal posterior segment in the left eye (Fig. 2). Ultrasonography confirmed the absence of alterations in the retina and choroid. Surgery was proposed to remove the staphyloma, with reconstruction of the eyeball and total corneoscleral transplant. During the operation, it was verified that the iris was completely adherent to the posterior portion of the cornea, the lens was dislocated to the anterior chamber, and there was a large quantity of vitreous.
Figure 2. Computed Tomography Showing a Bulge in the Anterior Segment of the Left Eye. The Posterior Segment Is Apparently Normal.
Histopathologic examination showed keratinization of the corneal epithelium, total disorganization of the stromal cells, and partial absence of the Descemet membrane and corneal endothelium. Atrophic iris lined the posterior cornea.
The patient recovered well from surgery, although opacity was observed on the corneal button within the first month after surgery that evolved into total conjunctivalization of the transplant. A scleral prosthesis was adapted to improve the cosmetic appearance (Fig. 3).
Figure 3. Final Outcome in a Patient with a Scleral Prosthesis.
The clinical and histopathologic findings in this case are typical of congenital anterior staphyloma, which in addition to causing functional disturbance is extremely disfiguring. Protrusion of the cornea between the eyelids results in exposure of the eyeball and can generate epithelial metaplasia and keratinization.3 Closure of the angle of the anterior chamber, caused by synechia of the iris with the posterior portion of the cornea, elevates intraocular pressure and contributes to an increase in excavation of the optic nerve.2
Histopathologic and electron microscope studies showed an absence of the Descemet membrane and corneal endothelium. The absence of endothelial cells suggests that this anomaly occurred during embryogenesis and did not originate from an inflammation.2
When there is no inflammation or evidence of maternal infection, there are three possible explanations for the malformation: (1) during embryogenesis, after separation of the lens, a fragile point remained in the central surface of the ectoderm, which made the formation of diverse layers in the cornea impossible; (2) an abnormality occurred in the differentiation of the anterior mesoderm4; and (3) an abnormality occurred in the migration of the cells from the neural crest.5
Although most patients are treated with enucleation, in this case it was decided that the eyeball should be preserved because the posterior segment was normal. Corneoscleral transplant was performed, but the lack of limbic cells and the extreme disorganization of the anterior segment of the eyeball were fundamental in the optical failure of the transplant. Still, some authors have achieved reasonable results in milder cases.6
Even with the functional failure of the eye, the corneoscleral transplant has allowed for better reconstruction, structurally improving the malformed eyeball and allowing prosthetic rehabilitation.
- Hamburg A. Congenital anterior staphyloma with retinal pro-lapse. Ophthalmologica. 1965;149:21–26. doi:10.1159/000304726 [CrossRef]
- Leff SR, Shields JA, Augsburger JJ, Sakowski AD Jr, Blair CJ. Congenital corneal staphyloma: clinical, radiological and pathological correlation. Br J Ophthalmol. 1986;70:427–430. doi:10.1136/bjo.70.6.427 [CrossRef]
- Stuart JA. Congenital anterior staphyloma. Surv Ophthalmol. 1963;54:393–395.
- Tanenbaum HL, Rosen DA. Congenital anterior staphyloma. Am J Ophthalmol. 1966;61:336–340.
- Bahn CF, Falls HF, Varley BS, Meyer RF, Edelhauser HF, Bourne WM. Classification of corneal endothelial disorders based on neural crest origin. Ophthalmology. 1984;91:558–563.
- Schanzlin DJ, Robin JB, Erickson G, Língua R, Minckler D, Pickford M. Histopathologic and ultrastructural analysis of congenital corneal staphyloma. Am J Ophthalmol. 1983;95:506–514.