The patient is a 30 year old male with Terrien's marginal degeneration.

There was severe peripheral thining of the superior cornea, with neovascularization and lipid deposition. Best-corrected visual acuity was impaired due to irregular astigmatism.

Extensive description of the case is reported on the "Clinical Cases" section.

To prevent further progression, avoid the risk of spontaneous perforation, and to improve visual function, a surgical approach was planned and proposed to the patient.

There are several reports in the medical literatura concerning surgical options for cases of severe Terrien's marginal degeneration. To avoid some of the risks associated with penetrating keratoplasties or full-thickness partial keratoplasties, a ring-shaped corneoscleral lamellar keratoplasty was performed.