Case Report 1 – Terrien’s Marginal Degeneration

Case Report for QUT 4th Year Optometry Students

Things to note:

TMD is rare, bilateral, asymmetric disease, males > females 3:1, 1/3 of all cases carry an inflammatory component, can rupture need to watch corneal thickness, stromal lipid deposits, absence of Bowmans and anterior stromal thinning

Terrien himself saw 3 cases in 30 years of practice. Watch lifestyle as 15% of cases spontaneously perforate. Differentiated from PMD due to vascularisation, lipid infiltration, or corneal ulceration which do not occur in PMD.

  • 23 yo female – soccer player / lawyer –
  • GH – unremarkable – no RA / autoimmune disorder
  • POH – Moderate myopia
  • OD: -3.25 / -0.50 x 61 DS (6/6)
  • OS: -5.00 DS (6/6)

Employ a stepped approach so the simplest option is the best option.

  • J&J One Day Moist
  • OD: 8.5 / 14.0 / -3.50   (6/6)
  • OD: 8.5 / 14.0 / -5.00  (6/6)

Peripheral Corneal Ectasia: Terrien Marginal Degeneration

An Evidence-Based Teaching Case Report and Stepped Contact Lens Management Approach

Prepared for QUT Bachelor of Vision Science / Master of Optometry — Year 4, Anterior Segment & Cornea

Mark Hinds, Optometrist

Founder & Principal Investigator, Ophthalmic Trials Australia

Learning Objectives

By the end of this case, students should be able to:

  • Describe the current (2023–2025) epidemiological and pathophysiological understanding of Terrien marginal degeneration (TMD).
  • Differentiate TMD from pellucid marginal degeneration (PMD), keratoconus, furrow degeneration, and Mooren ulcer using clinical and imaging features.
  • Apply a stepped, evidence-based approach to optical management of peripheral corneal ectasia, beginning with the least invasive option that achieves functional vision.
  • Recognise red flags for disease progression and perforation risk requiring escalation of monitoring or referral.

Case Presentation

A 23-year-old female, competitive soccer player and practising lawyer, presented for a routine contact lens review.

General Health

  • Unremarkable. No history of rheumatoid arthritis or other autoimmune/connective tissue disease.

Prior Ocular History

  • Moderate myopia, previously corrected in spectacles.

Refraction (unaided VA not recorded; best-corrected below)

EyeRefractionBCVA
OD−3.25 / −0.50 × 61 DS6/6
OS−5.00 DS6/6

Clinical note: the low-to-moderate against-the-rule/oblique astigmatism and preserved 6/6 BCVA place this presentation at an early, optically manageable stage. This is notable because TMD is classically a disease of middle-aged to older males; a young female presentation warrants careful differential diagnosis and closer monitoring given the longer disease trajectory ahead.

Background: Terrien Marginal Degeneration — Current Evidence

TMD is a rare, idiopathic, peripheral corneal thinning disorder first described by Félix Terrien in 1900, who documented only three cases across 30 years of practice [1]. Contemporary hospital-based series remain small: a 2025 Finnish cohort followed just 16 patients (32 eyes) over more than a decade, underscoring how uncommon the disease remains even in tertiary cornea clinics [1]. Historically reported as predominantly affecting males over 40 in a ratio of approximately 3:1, more recent series confirm a male predominance (65–75%) and bilateral involvement in the majority of cases (69–86%), though presentation is characteristically asymmetric [1], [9].

Pathophysiology remains incompletely understood. Two clinical variants are recognised: a slowly progressive, non-inflammatory form typically seen in older patients, and an inflammatory variant — accounting for roughly a third of cases — seen more often in younger patients and associated with recurrent episodes of redness, photophobia and pain [2], [6]. Despite investigation by histopathology, electron microscopy, immunohistochemistry, in vivo confocal microscopy, and serum immunocomplex studies, no consistent inflammatory marker has been identified, and diagnosis continues to rely on clinical and topographic exclusion of other peripheral corneal disease [1].

Characteristic findings include stromal lipid deposition at the leading edge of the thinned area, superficial vascularisation with a radial pattern, an intact epithelium overlying the lesion, and loss of Bowman’s layer with anterior stromal thinning progressing to gutter formation [3]. Progression is typically slow — recent longitudinal data report a median astigmatic progression of only 0.03–0.15 D/year and thinning progression of roughly 13–22 µm/year in the majority of eyes — but the clinical course is unpredictable, and corneal thickness must be monitored regularly because spontaneous perforation, while uncommon, is well documented, including in young patients following only trivial trauma or eye rubbing [1], [10], [11].

Differentiating TMD from Pellucid Marginal Degeneration

PMD is a separate ectatic disorder that shares peripheral thinning with TMD but differs in several clinically important respects. PMD classically produces an inferior band of thinning with a characteristic ‘crab-claw’ topographic pattern and against-the-rule astigmatism, but without vascularisation, lipid infiltration, or corneal ulceration — all of which can occur in TMD. PMD also spares the epithelium and Bowman’s layer far more consistently, and true perforation is rarer than in advanced TMD [4], [5]. This distinction is clinically important because management pathways diverge: PMD is managed largely along the keratoconus/ectasia treatment pathway (including corneal cross-linking protocols now being studied in PMD), whereas TMD’s vascular and lipid component and perforation risk demand closer structural monitoring even when vision remains good [4], [5].

FeatureTerrien Marginal DegenerationPellucid Marginal Degeneration
Typical locationSuperior / superonasal, circumferentialInferior band, 1–2mm from limbus
VascularisationPresent (radial pannus)Absent
Lipid depositionPresent at leading edgeAbsent
Ulceration / perforation riskCan occur (~15% spontaneous perforation reported historically)Rare
Epithelium / Bowman’sEpithelium intact; Bowman’s absent/degeneratedBoth typically preserved until late

Evidence-Based Management: A Stepped Approach

Current guidance for peripheral corneal ectasias, including the American Academy of Ophthalmology’s 2023 Corneal Ectasia Preferred Practice Pattern, endorses a stepped approach in which the simplest optical correction achieving safe, functional, stable vision is preferred before escalating to more complex or invasive options [7]. This principle — consistent across TMD, PMD and keratoconus literature — reflects both cost-effectiveness and the reversibility of conservative options [7], [8]:

  • Step 1 — Spectacles: appropriate for regular, low-to-moderate astigmatism where corneal irregularity is minimal.
  • Step 2 — Soft toric contact lenses: first-line specialty option where astigmatism remains reasonably regular; provides the best comfort-to-complexity ratio and is the option of choice when it achieves target visual acuity.
  • Step 3 — Custom soft or corneal rigid gas-permeable (RGP) lenses: indicated once irregular astigmatism or reduced BCVA through soft lenses develops; RGPs mask irregularity via the tear lens but can be less comfortable and less stable over ectatic/peripherally thinned corneas.
  • Step 4 — Scleral lenses: considered when RGP intolerance, decentration, or greater surface irregularity limits the corneal RGP option; scleral lenses vault the affected peripheral zone entirely, which is particularly relevant in TMD given the peripheral (rather than central) location of pathology.
  • Step 5 — Surgical intervention: lamellar/tectonic patch grafting is reserved for eyes with critically thin corneas (historically cited around ≤150µm), impending or actual perforation, or failure of optical correction to provide functional vision.

This stepped hierarchy is directly supported by outcomes data: modern keratoconus and ectasia contact lens literature confirms that soft toric lenses remain a viable, evidence-supported option for regular-to-mildly-irregular astigmatism, while RGP and scleral lenses are reserved for eyes that fail this first-line approach [8].

Application to This Case: Contact Lens Trial

Following the stepped principle above, a soft toric daily disposable lens (Johnson & Johnson 1-Day Acuvue Moist) was trialled as the first-line, least invasive option:

EyeBase CurveDiameterPowerVA
OD8.514.0−3.50 DS6/6
OS8.514.0−5.00 DS6/6

Outcome: 6/6 unaided-equivalent VA was achieved bilaterally with a standard spherical soft daily lens (astigmatic correction was not required at this stage given the low, regular cylinder present). This confirms that the disease is currently at an early, optically regular stage and validates the stepped approach — there is no current indication to escalate to RGP or scleral correction. Given the patient’s occupation (soccer) and the well-documented risk of TMD progression and perforation with ocular trauma or vigorous eye rubbing, a daily disposable modality was also selected for its lower risk of surface complications and ease of hygiene during sport [10], [11].

Monitoring and Patient Safety Plan

  • Baseline and serial corneal pachymetry / anterior segment OCT at the area of thinning, given documented perforation risk with critical thinning.
  • Serial corneal topography to monitor astigmatic and topographic progression (annual review is reasonable at this stable stage; more frequent review if progression is detected).
  • Patient education regarding avoidance of eye rubbing and use of protective eyewear during contact sport, given the documented association between trauma/eye rubbing and acute perforation in young patients with TMD.
  • Clear return precautions: sudden pain, photophobia, discharge, or acute vision change warrant same-day review to exclude perforation or hydrops.
  • Re-refer for cross-sectional imaging or corneal specialist opinion if progression, inflammatory signs, or reduction in BCVA despite optimal contact lens correction develop.

Key Take-Home Points for Students

  • TMD is rare, bilateral, and asymmetric, with a historical male predominance of ~3:1; however atypical presentations (young, female) do occur and should not be dismissed.
  • Roughly one-third of cases carry an inflammatory component; distinguishing this variant matters for both prognosis and potential systemic work-up.
  • Vascularisation, lipid infiltration, and risk of ulceration/perforation differentiate TMD from PMD, which lacks these features.
  • A stepped management approach — spectacles → soft toric → RGP → scleral → surgical — remains the evidence-based standard: the simplest option that achieves safe, functional vision is the correct option.
  • Corneal thickness must be actively monitored throughout follow-up, as perforation, though uncommon, is a recognised and potentially sight-threatening complication.

References

1. Ruutila M, Repo P, Immonen AT, Turunen JA, Lokki ML, Lokki AI, Moilanen J, Krootila K, Kivelä TT. Progression and topographic subtypes of Terrien marginal degeneration. Acta Ophthalmol. 2025. doi:10.1111/aos.17524

2. Ding Y, Murri MS, Birdsong OC, Ronquillo Y, Moshirfar M. Terrien marginal degeneration. Surv Ophthalmol. 2019.

3. Moshirfar M, Villarreal A, Ronquillo Y. Furrow Degeneration. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; updated 8 Aug 2023.

4. Tsatsos M, Koulotsiou K, Giachos I, Tsinopoulos I, Ziakas N. Pellucid Marginal Degeneration: A Comprehensive Review of Pathophysiology, Diagnosis, and Management Strategies. J Clin Med. 2025;14(15):5178. doi:10.3390/jcm14155178

5. Vieira IV, Fan VH, Yu CQ. Update on pellucid marginal degeneration. Graefes Arch Clin Exp Ophthalmol. 2025. doi:10.1007/s00417-025-07022-1

6. Arnalich-Montiel F. Systemic treatment and surgical intervention in inflammatory Terrien disease. Taiwan J Ophthalmol. 2024;14(1):108–111. doi:10.4103/tjo.TJO-D-23-00176

7. American Academy of Ophthalmology. Corneal Ectasia Preferred Practice Pattern. San Francisco, CA: American Academy of Ophthalmology; 2023.

8. Lim L, Lim EWL. Current perspectives in the management of keratoconus with contact lenses. Eye (Lond). 2020;34(12):2175–2196.

9. Baijal V, Palit MG, Choudhary T, Gurunadh VS, Shanker S. Terrien’s marginal degeneration. Med J Armed Forces India. 2017;73(1):83. doi:10.1016/S0377-1237(17)30330-1

10. Fernandes M, Vira D. Patch graft for corneal perforation following trivial trauma in bilateral Terrien’s marginal degeneration. Middle East Afr J Ophthalmol. 2015;22(2):255–257. doi:10.4103/0974-9233.151873

11. Khurana S, Gupta PC, Kumar A, Ram J. Globe rupture following eye rubbing in a case of Terrien’s marginal degeneration in a young male. Indian J Ophthalmol. 2020;68(11):2493–2494. doi:10.4103/ijo.IJO_1858_19

Prepared by Mark Hinds, Optometrist, in his role as Founder and Principal Investigator of Ophthalmic Trials Australia, for teaching purposes at the Queensland University of Technology School of Optometry and Vision Science.