14.2 SEAL, CLARE, VLK, SLK & CLPU
Key Takeaways
SEAL (Superior Epithelial Arcuate Lesion) is an arcuate staining at 12 o'clock under the upper lid caused by mechanical interaction of a high-modulus SiHy lens edge with the superior cornea; fix with lower modulus, flatter BC, thinner edge.
CLARE (Contact Lens Associated Red Eye) is a sterile inflammatory response to gram-negative bacterial endotoxins trapped under the lens, classically in extended wear; discontinue EW and treat inflammation.
VLK (Vascularized Limbal Keratitis) features limbal vascularization and inflammation, usually superior, in RGP or scleral wearers; requires lens discontinuation and anti-inflammatory treatment.
SLK (Superior Limbic Keratoconjunctivitis) inflames the superior limbus and tarsal conjunctiva, is associated with thyroid disease, and is aggravated by soft lens friction.
CLPU (Contact Lens Peripheral Ulcer) is a small peripheral infiltrate/ulcer that is sterile early but may become infected; culture and treat, do not assume sterility.
Named Contact Lens Complications
Quick Answer: Five eponymous complications dominate follow-up: SEAL (arcuate 12 o'clock mechanical), CLARE (sterile inflammatory red eye from endotoxins in extended wear), VLK (limbal vascularization + inflammation, RGP/scleral), SLK (superior limbitis with thyroid association), and CLPU (small peripheral ulcer — sterile early, may become infected). Differentiate by location, signs, and wear modality.
Comparison Table
| Condition | Location | Key Signs | Etiology | Modality |
|---|---|---|---|---|
| SEAL | 12 o'clock arcuate under upper lid | Arcuate epithelial staining, mild injection | Mechanical edge interaction | High-modulus SiHy, steep fit |
| CLARE | Diffuse conjunctival injection, infiltrates | Red eye, infiltration, no ulcer | Endotoxins from gram-negative bacteria | Extended wear |
| VLK | Superior limbus | Vascularization + inflammation at limbus | Chronic inflammation | RGP, scleral |
| SLK | Superior limbus + tarsal conjunctiva | Papillary reaction, foreign body sensation, photophobia | Soft lens friction; thyroid association | Soft lens |
| CLPU | Peripheral cornea | Small infiltrate/ulcer, mild injection | Inflammatory; sterile early, may seed | Any |
SEAL — Superior Epithelial Arcuate Lesion
Presentation: Arcuate (arc-shaped) staining at 12 o'clock, under the upper lid, typically in a high-modulus SiHy lens wearer. The lesion is an epithelial split caused by the mechanical interaction of the lens edge with the superior cornea under upper lid pressure.
Risk factors: High-modulus SiHy (first-generation), steep base curve, thick lens edge, large diameter with edge impingement.
Management:
- Switch to a lower-modulus SiHy or hydrogel lens.
- Flatten the base curve to reduce edge lift against the cornea.
- Select a lens with a thinner, more rounded edge.
- Reduce diameter if edge impingement is the trigger.
- Mild SEAL may heal with lens discontinuation alone; severe cases need prophylactic antibiotics and short topical steroid under ophthalmology supervision.
CLARE — Contact Lens Associated Red Eye
Presentation: Acute red eye in an extended-wear patient with conjunctival injection, corneal infiltration, but no epithelial ulcer. Pain is moderate; discharge is minimal. Classically bilateral or unilateral after overnight wear.
Etiology: Sterile inflammatory response to endotoxins produced by gram-negative bacteria (often Pseudomonas or gram-negative flora) colonizing the lens or storage case. The intact epithelium prevents true infection, but the inflammatory cascade produces infiltrates.
Management:
- Discontinue extended wear permanently — CLARE is a sentinel event for EW risk.
- Remove lens; culture lens and case if any epithelial defect is present.
- Topical antibiotic prophylaxis until epithelium intact.
- Topical steroid only under ophthalmology supervision and only after infection excluded.
- Refit to daily wear with daily disposable if possible.
VLK — Vascularized Limbal Keratitis
Presentation: Inflammation and vascularization at the limbus, usually superior, with staining and epithelial whorls. Most common in RGP or scleral wearers with chronic edge interaction at the limbus.
Etiology: Chronic inflammation at the limbus from lens edge mechanical trauma and hypoxia drives vessel extension into clear cornea.
Management:
- Discontinue lens wear to halt vascularization.
- Anti-inflammatory treatment (topical steroid under ophthalmology).
- Refit with a lens that vaults the limbus (larger scleral, different RGP edge).
- Document pre-fit limbal status — pre-existing vessels recur faster.
SLK — Superior Limbic Keratoconjunctivitis
Presentation: Inflammation of the superior limbus and superior tarsal conjunctiva with foreign body sensation, photophobia, and stringy mucus. Soft lens wearers may develop a friction-related SLK; thyroid disease is a systemic association that must be ruled out.
Signs: Papillary reaction on superior tarsal conjunctiva, staining of superior cornea and limbus, thickening and redundancy of superior bulbar conjunctiva.
Management:
- Discontinue soft lens wear temporarily.
- Treat thyroid disorder if present (workup: TSH, free T4).
- Topical lubrication; may need supratarsal steroid injection or 10% N-acetylcysteine for severe cases (ophthalmology).
- Refit with a lens that minimizes superior friction (different material, lower modulus, smaller diameter).
CLPU — Contact Lens Peripheral Ulcer
Presentation: Small peripheral corneal infiltrate or ulcer with mild to moderate injection. Peripheral location is the key discriminator from microbial keratitis, which tends to be central and more severe.
Pathophysiology: Inflammatory response — often sterile in early stage, but the epithelial break can seed bacterial infection. Do not assume sterility.
Management:
- Culture the ulcer and lens/case before treatment if any epithelial defect is present.
- Discontinue lens wear.
- Antibiotic treatment — broad-spectrum topical, often fortified tobramycin/cefazoline or fluoroquinolone.
- Short course of steroid only after infection is excluded and under ophthalmology.
- Refit after complete healing; consider daily disposables.
Key Takeaways
- SEAL = mechanical 12 o'clock arc; lower modulus, flatten BC, thin edge.
- CLARE = sterile endotoxin red eye; stop extended wear.
- VLK = limbal vessels + inflammation; RGP/scleral; discontinue and treat inflammation.
- SLK = superior limbitis; rule out thyroid disease.
- CLPU = peripheral infiltrate/ulcer; culture, do not assume sterile.
An extended-wear SiHy patient presents with a red eye, conjunctival injection, multiple peripheral infiltrates, and an intact epithelium (no ulcer). Which diagnosis is MOST likely?
CLPU (Contact Lens Peripheral Ulcer)
Microbial keratitis (Pseudomonas)
Dendritic herpes simplex keratitis
CLARE (Contact Lens Associated Red Eye)
A soft lens wearer reports chronic foreign body sensation and photophobia. Slit-lamp reveals staining and papillary reaction on the SUPERIOR tarsal conjunctiva and inflammation of the superior limbus. Which systemic association MUST be evaluated?
Rheumatoid arthritis
Thyroid disease (Graves'/hyperthyroidism)
Multiple sclerosis
Type 2 diabetes
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