Cornea
Terrien Marginal Degeneration
Also known as: TMD, Terrien degeneration, peripheral corneal thinning, superior corneal thinning, against-the-rule astigmatism, non-inflammatory corneal thinning, marginal corneal degeneration, peripheral corneal degeneration
Filed as: Soon
Source-cited from the record's own evidence list. Clinical content programme led by Dr Ankit Mathur, PhD, Grad Cert Ocu Thera, B.S. Optom. How the clinical content is governed
Clinical decision support only
Overview
A rare peripheral corneal thinning degeneration, classically superior or superior-nasal, with an intact epithelium, superficial vascularisation, lipid deposition at the leading edge, and progressive against-the-rule or irregular astigmatism. It is usually non-inflammatory or minimally inflammatory. The key safety task is to separate Terrien marginal degeneration from active inflammatory or ulcerative disease such as peripheral ulcerative keratitis, Mooren ulcer, marginal keratitis, infectious keratitis, pellucid marginal degeneration, keratoconus, or keratoglobus.
Recognition
Symptoms: what patients report
- Often asymptomatic early and found on slit lamp or topography.
- Gradual blur, ghosting, glare, or spectacle instability from increasing against-the-rule or irregular astigmatism.
- Usually minimal pain and minimal redness unless another inflammatory diagnosis is present.
- Contact lens intolerance may develop if irregular astigmatism progresses.
- Acute pain, photophobia, epithelial defect, or marked redness should redirect away from uncomplicated Terrien marginal degeneration.
Signs: what the examination shows
- Peripheral corneal thinning, classically superior or superior-nasal, often circumferential and asymmetric.
- Intact epithelium over the thinned area in uncomplicated disease.
- Fine superficial vascularisation extending into the thinned peripheral cornea.
- Yellow-white lipid line or leading edge anterior to the area of thinning.
- Against-the-rule or irregular astigmatism on refraction, keratometry, or topography.
- Little or no conjunctival/scleral inflammation in typical disease.
- No overhanging ulcer edge, no epithelial ulceration, no infiltrate, and no active corneal melt in uncomplicated TMD.
What OptoGuide™ covers for terrien marginal degeneration
- Pattern reasoning: what this combination of findings points to, and its differentiators
- Don't-miss risks and escalation triggers
- Management tiers with linked Australian therapeutics
- Referral urgency, specialty, and letter drafting
Sources
- Terrien Marginal Degeneration — EyeWiki
- Anterior Eye Disease and Therapeutics A-Z (Bruce & Loughnan) — standard reference text
- Peripheral Ulcerative Keratitis Associated With Vasculitis Manifesting Asymmetrically as Fuchs Superficial Marginal Keratitis and Terrien Marginal Degeneration. Keenan JD, Mandel MR, Margolis TP. Cornea. 2011;30(7):825-7
- High-Resolution Optical Coherence Tomography in the Differentiation of Inflammatory Versus Noninflammatory Peripheral Corneal Thinning. Rodriguez M, Yesilirmak N, Chhadva P, et al. Cornea. 2017;36(1):48-52.
- Update on pellucid marginal degeneration. Vieira IV, Fan VH, Yu CQ. Graefe's Archive for Clinical and Experimental Ophthalmology = Albrecht Von Graefes Archiv Fur Klinische Und Experimentelle Ophthalmologie. 2026;264(2):
Standard texts: Kanski's Clinical Ophthalmology: A Systematic Approach, The Wills Eye Manual, Oxford Handbook of Ophthalmology, Oxford American Handbook of Ophthalmology, Signs in Ophthalmology: Causes & Differential Diagnosis.