Terrien’s marginal degeneration (TMD)is a rare bilateral painless corneal degeneration with unknown etiology, associated with corneal neovascularization, opacification, and lipid deposition. Degeneration typically begins superiorly, the thinning progress circumferentially, rarely involves inferior limbus.

We present the case of A 68-year-old man who complained of gradually visual loss in both eyes since several years ago without any notable point in his past medical history and medication history, referred to our hospital. His best-corrected visual acuity was 20/70 in the right eye and 20/50 in the left one. The fundoscopic examination was normal. Slit lamp examination revealed intact epithelium with peripheral stromal thinning, superficial vascularization and lipid deposition at the leading edges. Corneal topography revealed ATR astigmatism and reverse crab claw pattern in Keratometry axial map and central thickening with peripheral thinning in corneal thickness map. Cornea in anterior elevation map was greater than 15 microns, in some peripheral area had an irregular pattern and In posterior elevation map was greater than 20 micron with an irregular pattern in some peripheral area. cornea-thickness spatial profile (CTSP) revealed the tendency to be a linear curve alike PMD.

According to the findings from clinical history, physical examination and imaging results; Terrien’s marginal degeneration was diagnosed for the patient.

Terrien's marginal degeneration should be noted as a differential diagnosis in the bilateral gradually visual decrease by the eye care providers.