How often it ends lens wear
The largest population-level estimate comes from a survey of scleral lens practitioners covering 72,605 wearers. Over one year, 0.53% discontinued wear because of corneal neovascularization, compared with 1.2% for corneal edema, 0.45% for microbial keratitis, and 0.20% for limbal stem cell deficiency. These are period prevalences of stopping wear, not incidence rates of vessels.[1] Many eyes with some vascular change continue in a modified lens and would not appear in that figure.
Why vessels develop under a scleral lens
A 2025 review describes lens-related vascularization as growth from the limbal plexus associated with prolonged hypoxia, inflammation, infection, trauma, poor compliance, and poorly fitted lenses, including limbal bearing, as well as overwear or extended wear.[2] It distinguishes superficial vessels, generally linked to hypoxia, from deeper and larger vessels that may indicate inflammation from the underlying disease.[2]
Oxygen. The lens and reservoir sit in series over the cornea. Theoretical calculations in 2012 predicted that most scleral lens systems of the time would produce some hypoxic swelling and recommended high-Dk materials, thin lenses, and limited clearance.[4] The peripheral cornea is not spared: in 10 healthy adults, stromal swelling was as large near the limbus as centrally, and rose with reservoir thickness.[5] A single small limbal fenestration reduced peripheral swelling near the fenestration in 9 healthy participants.[6]
Pressure. The review lists limbal bearing and tight landing zones as triggers.[2] In a single-subject OCT angiography pilot, perilimbal vascular flow interruption grew from 0% to 25% to 75% as lens sagittal height increased.[8] In 27 eyes with limbal stem cell deficiency wearing scleral lenses, LSCD stage worsened in 44.4%, and imaging in 5 eyes showed limbal compression and delayed fluorescein filling, which the authors suggest reflects limbal hypoxia.[7]
The underlying disease. Vascularization is a common repair pathway in severe corneal and ocular surface disease, and exposure keratopathy is among the conditions the 2025 review lists as prone to it.[2] Limbal stem cell deficiency brings conjunctival epithelium and vessels onto the cornea by itself.[9] In these eyes, new vessels may not be lens-related at all.
What to do at your visits
A 2022 review of scleral lens assessment notes that an improperly fitted lens can cause complications ranging from swelling and redness to infiltrates or neovascularization, and recommends documenting slit lamp findings at baseline for comparison, with photography wherever possible.[3] In practice:
- Baseline: photograph the limbus in all quadrants before the fit, noting existing vessels and ghost vessels, and their depth.
- Follow-up: compare against the photographs, looking for new vessels, extension toward the visual axis, active (perfused) versus ghost vessels, and associated haze, lipid, or edema.
- Correlate with the lens: check whether vessels sit under a zone of limbal bearing or a tight landing quadrant, and note wear hours, sleeping in lenses, and any change in lens or solution.
- Report new or advancing vessels to the fitter promptly, with photographs.
What the fitter can change
The review describes refitting from older polymethyl methacrylate or low-permeability materials to modern high-Dk materials, which it reports has reversed vascularization in some cases, along with optimizing lens and reservoir thickness to limit hypoxia and relieving limbal bearing or landing zone pressure.[2] For signs of hypoxia, a 2018 review also lists shortening the wear schedule and adding fenestrations.[9]
When scleral devices are part of treatment
In severe surface disease, a well-fitted device can be part of controlling vessels rather than causing them.
- PROSE as a drug-delivery system: in a retrospective, non-comparative series of 13 sequential patients at one center, followed for a mean of 5.1 years, preservative-free bevacizumab was added to the PROSE reservoir. Vessels regressed in 12 (92%) and best-corrected acuity improved in 10 (77%). Vessels progressed in one eye after bevacizumab stopped, and no ophthalmic or systemic complications were reported. Diagnoses included Stevens-Johnson syndrome (7), ocular GVHD (2), and corneal transplant (2).[10] Bevacizumab use on the cornea is off-label, and one author was employed by the PROSE provider during the study period.[10]
- PROSE alone: a report of two patients (four eyes) with Stevens-Johnson syndrome or TEN described regression of vessels and clearing of opacity with PROSE, in devices that all had back-surface channeled haptics. The authors call for more research into which design features matter.[11]
Common questions
Should a patient with new vessels stop wearing the lens?
That depends on how far the vessels extend, how fast they are advancing, and what the lens is doing for the eye. Report new or advancing vessels to the fitter promptly so the fit and oxygen supply can be reviewed. In a practitioner survey, 0.53% of wearers stopped over a year because of neovascularization, which means most eyes with some vascular change continue in a modified lens.
Can a refit make lens-related vessels regress?
A 2025 review reports that refitting from older low-permeability materials to modern high-Dk materials has reversed vascularization in some cases, and recommends optimizing lens and reservoir thickness and relieving limbal or landing zone pressure. Regression of established vessels is not guaranteed.
Is bevacizumab in a PROSE device an approved treatment?
No. Topical bevacizumab is used off-label for corneal neovascularization. The PROSE data come from one center's retrospective series of 13 patients. Treatment decisions belong to the cornea specialist and the PROSE or scleral lens team together.
Do scleral lenses help vessels regress in surface disease?
In selected cases. Beyond the bevacizumab series, a report of two patients with Stevens-Johnson syndrome or TEN described regression of vessels and clearing of opacity over time with PROSE, in devices with channeled haptics. Two cases can't tell you how often this happens.