Why scleral lenses are used in neurotrophic keratitis
The cornea is one of the most densely innervated tissues in the body.[12] When trigeminal input is lost, epithelial maintenance and healing fail, and the cornea is at risk of persistent epithelial defects, ulceration, and perforation. Herpes simplex and zoster are the most common causes; others include trigeminal surgery, acoustic neuroma, diabetes, and chronic topical medication toxicity.[2]
A scleral lens vaults the cornea and holds a reservoir of non-preserved saline against it, shielding the epithelium from lid shear and evaporation. A review of therapeutic use describes that liquid bandage as able to heal the surface, prevent recurrent defects, and preserve vision, and lists scleral lenses alongside preservative-free lubricants, punctal plugs, tarsorrhaphy, amniotic membrane, and therapeutic soft lenses as options.[2] It also notes that neurotrophic patients may have signs without symptoms and are still good candidates.[2] A 2025 review adds that, in selected cases, the sustained protection may delay or avoid surgery.[5]
A 2025 review describes daily scleral lens wear after healing as protecting against recurrent breakdown, improving vision by masking irregular astigmatism from abnormal epithelium and scar, and, with long-term wear, coinciding with improvement of chronic opacities.[3]
What the evidence is
- No trials. A 2021 review found no randomized trials comparing contact lens therapy with other neurotrophic treatments, or comparing lens types. Case reports and limited series suggest scleral lenses may be safe and effective at any stage, preserving epithelial integrity and sometimes improving vision.[1]
- Pediatric case: a 3-year-old with congenital trigeminal aplasia whose epithelial defect persisted after an 8-week trial of recombinant nerve growth factor healed with a PROSE device, with acuity improving from 20/300 to 20/70.[9]
- Persistent epithelial defects of mixed cause, including neurotrophic disease, are where most of the outcome data sit (below).
Healing an active defect: continuous wear
Three series from specialty centers describe continuous or overnight wear for persistent epithelial defects that had failed conventional therapy. They included various causes, not only neurotrophic disease.
| Series | Eyes | Approach | Healed | Microbial keratitis |
|---|---|---|---|---|
| Rosenthal 2000 | 14 | Extended wear; antibiotic and steroid in the reservoir or before insertion in 12 eyes | 8 of 14 | 4 of 14[6] |
| Lim 2013 | 20 | Overnight PROSE wear with non-preserved moxifloxacin in the reservoir | 17 of 20 | None[7] |
| Ciralsky 2015 | 8 | Standardized 24-hour PROSE wear, daily removal and cleaning, BAK-free fluoroquinolone in reservoir | 8 of 8 | None[8] |
In the 2000 series, defects healed in 5 of 7 Stevens-Johnson eyes and 3 of 7 others, while microbial keratitis occurred in 4 eyes and graft failure in 1, all requiring repeat keratoplasty; the authors concluded that microbial keratitis represents a significant risk.[6] In 2013, the same center reported re-epithelialization in 17 of 20 eyes with a median 8.5 days of overnight wear and no microbial keratitis, and attributed the lower infection rate to adding a non-preserved fourth-generation fluoroquinolone to the reservoir.[7] In the 2015 standardized protocol, all 8 eyes healed without microbial keratitis; 4 had recurrences, which responded to resuming continuous wear.[8]
The 2025 neurotrophic review describes continuous short-term scleral wear as useful for refractory defects, followed by daily wear once the surface heals.[3] These protocols were run by experienced centers with close follow-up. They are not a basis for an unsupervised patient to sleep in a lens.
The central risk: infection without pain
A 2022 review cautions that any contact lens in a neurotrophic cornea requires extreme caution, because reduced sensation blunts the pain that would normally signal infection, and notes that some authors advocate prophylactic antibiotic drops for scleral lens wearers with neurotrophic disease.[4] Risk compounds in eyes with other surface disease or immunosuppression: in a case series of three post-keratoplasty scleral wearers with microbial keratitis, all had concurrent surface disease and were on topical or systemic immunosuppression.[11]
What this means for co-management:
- Scheduled exams carry the load. Agree on a visit interval with the fitter that does not depend on the patient noticing a problem, shorter during any continuous-wear phase.
- Teach visual warning signs, not pain: blur that doesn’t clear with lens removal, redness, discharge, a white spot.
- Check the regimen at every visit: fresh non-preserved saline for each fill, no topping off, case hygiene, and whether any antibiotic is being added to the reservoir and by whose instruction.
- Look under the lens and after removal: infiltrates, epithelial defects, stromal thinning, and new vessels.
Coordinating drug therapy
Nerve growth factor. The cenegermin label says to remove contact lenses, therapeutic or corrective, before applying the drop, because a lens could limit distribution to the corneal lesion, and to wait 15 minutes before reinserting.[10] For a scleral wearer, the dosing schedule determines when the lens can be in, so plan the course with the fitter before it starts.
Other topical drugs. The therapeutic scleral lens review advises using topical medications before or after lens wear, waiting at least 10 minutes before applying the lens, and avoiding benzalkonium chloride-preserved drops in surface disease where alternatives exist.[2] The 2025 neurotrophic review lists BAK, topical anesthetics, glaucoma drugs, and contact lenses among iatrogenic contributors to neurotrophic disease, so the whole medication list is worth reviewing.[3]
Reservoir additives. Antibiotics added to the reservoir appear in the defect-healing protocols above. Any additive is a joint decision between you and the fitting center, with clear instructions to the patient.
Common questions
Should a neurotrophic patient with an active epithelial defect wear the lens overnight?
Only as part of a deliberate, supervised protocol run by the fitting center with your agreement. Published continuous-wear protocols for persistent epithelial defects used brief daily removal for cleaning and fresh reservoir fluid, a non-preserved antibiotic in the reservoir, frequent examination, and a switch to daytime wear once the epithelium closed. An early series without that standardization reported microbial keratitis in 4 of 14 eyes.
Can a scleral lens be combined with cenegermin?
The two have been used in sequence, and the label addresses contact lenses: remove the lens before each dose and wait 15 minutes before reinserting it, because a therapeutic or corrective lens could limit drug distribution. For a scleral wearer that means planning lens wear around the dosing schedule, which is worth settling with the fitter before starting.
What should the patient watch for if they can't feel pain?
Changes they can see: vision that drops and doesn't clear when the lens is out, new redness, discharge, a white spot on the cornea, or a lens that suddenly feels or looks different. Tell them not to wait for pain, and keep their scheduled visits even when the eye feels fine.
Are soft bandage lenses a reasonable alternative?
They are widely used and readily available. A 2025 review notes they can protect the epithelium and help defects heal, but cautions that overuse has side effects, and a 2022 review reports scleral lenses working in neurotrophic eyes previously treated with soft lenses. The choice depends on stage, lid status, and how closely the patient can be followed.