Optimal keratoconus (KCN) visual rehabilitation requires a coordinated, efficient workflow between corneal surgeons and specialty contact lens optometrists. Advanced surgical interventions such as deep anterior lamellar keratoplasty, corneal collagen cross-linking (CXL), and anterior lamellar keratoplasty with regional segments (ALKRS) have transformed the structural management of corneal ectasia.^{1,2,3,4,5,6,7} Within the United States, customized allogeneic tissue addition is known as corneal tissue addition keratoplasty (CTAK; CorneaGen), whereas internationally it is known as corneal allogenic intrastromal ring segments (CAIRS). In our practice, we use the generic term ALKRS. Although these techniques stabilize and improve the corneal topography, most patients still obtain improved vision with scleral contact lenses over spectacles.^8,9 By establishing clear communication pathways, coordinating surgical-to-fitting timelines, and leveraging high-technology imaging such as tomography and anterior-segment optical coherence tomography (AS-OCT), a collaborative practice can maximize patient outcomes while significantly reducing chair time and patient frustration.^10,11

The Evolution of Keratoconus Management

Twenty years ago, management was mostly reactive: A KCN patient wore a rigid contact lens (RGP) until the cornea progressed to the point of needing a penetrating keratoplasty (PK). The introduction of intrastromal corneal ring segments—such as Intacs, made of synthetic plastic over 20 years ago—offered an intermediary surgical step designed to flatten the central cornea. Yet Intacs could erode and be uncomfortable, in addition to complicating subsequent contact lens fittings. Corneal cross-linking started with investigational trials in the United States in 2008 and was first approved in 2016.^12,13 Epithelium-on CXL was approved in October 2025 (Epioxa; Glaukos).¹⁴ Corneal cross-linking allowed stabilization of the cornea, reducing the progression toward transplant when KCN was identified early.

Customized allogenic tissue addition techniques like ALKRS, CTAK, and CAIRS have also shifted our treatment strategy, typically improving spectacle-corrected vision and continued ability to wear a contact lens. This tissue addition adds structural thickness to the thinnest zones of the ectatic cornea, flattens the steepest regions of the cone, and reduces severe higher-order aberrations (HOAs). Patients appreciate an analogy, so we explain that this is akin to a “girdle or Spanx” for the cornea. 

Despite the significant topographic improvements achieved by ALKRS, surgical intervention alone does not eliminate the irregular astigmatism inherent to significant KCN. Therefore, we view these surgical and contact lens options as synergistic pathways for highly efficient, stable visual rehabilitation for the KCN patient. An efficient, high-volume cornea practice relies on a coordinated workflow where the corneal surgeon and the specialty lens optometrist work in unison.

Building a Collaborative Care Model

When the corneal surgeon evaluates a patient for CXL and/or ALKRS, our team discusses with the patient that they will still require scleral contact lenses postoperatively to achieve optimal visual results. Typically, we will perform CXL at the same surgical setting as ALKRS.^5,6 The eyes are usually operated 2 months apart to allow visual rehabilitation of the first eye before the second eye is done. If patients have not been fit with contacts before, we’ll arrange an appointment with the specialty lens optometrist about 1 month after the first-eye surgical procedure. If they are already wearing a contact and have reasonable vision, then we allow them to resume that same contact at a month after the combined ALKRS and CXL procedure. 

The optometrist discusses visual needs with patients and outlines how to achieve long-term functional vision. Patients with KCN have significant lower-order and higher-order optical aberrations that cannot be fully corrected with spectacles or soft contact lenses.^8,9 Scleral lenses, which vault entirely over the irregular cornea and rest comfortably on the less sensitive bulbar conjunctiva, create an optimal, fluid-filled tear reservoir. This neutralizes the irregular corneal surface, masks the underlying irregularity, and delivers improvements in the quality and stability of vision. The patient benefits from the optometrist's expertise in manipulating lens geometry to achieve good vault, stability of movement, limbal clearance, refractive results, and a physiologic fit for the underlying cornea before and after surgical manipulation.

Timing the Transition to Scleral Lenses

A frequent point of inefficiency is ambiguity regarding when a patient is ready to transition from surgical postoperative care to contact lens fitting. Initiating a fit too early can mechanically compromise healing incisions, disrupt epithelial remodeling, or result in a moving topographic target as the cornea settles. Conversely, delaying the fit unnecessarily prolongs the patient's visual disability, reducing overall satisfaction.

Our practice has seen that the optimal window to initiate a scleral contact lens fit is 1 to 2 months following the ALKRS procedure.^5,6 By 4 to 8 weeks, the femtosecond laser–cut channels are structurally stable, the donor tissue inlay has integrated into the corneal tissue (with no physical movement typically noted after the first couple of days), and the overlying epithelium has finished healing. Although minor long-term topographic shifts can occur over the first few years, the overall corneal contour is stable enough at 1 to 2 months to achieve a durable scleral lens fit.

A Staged Bilateral Treatment Timeline

Most patients present with a need for intervention in both eyes. Therefore, a proactive, staged timeline prevents visual disruption and optimizes clinic flow:

1. Week 0: The corneal surgeon performs the ALKRS and CXL procedures on the first eye (typically the structurally worse or more progressive eye).

2. Weeks 1 to 4: The patient undergoes standard surgical postoperative monitoring as the eye heals and the topography stabilizes.

3. Months 1 to 2: The optometrist verifies surgical incision and epithelial healing and initiates the fitting for this first eye (or verifies the presurgical fit).

4. Months 2 to 3: If the fit is adequate and the patient can function with the first eye, the surgeon performs the ALKRS and CXL procedures on the second eye.

5. Months 3 to 5: As the patient adapts to wearing and handling their custom scleral lens on the first eye, the second eye undergoes postoperative healing that takes 1 to 2 months. The optometrist then verifies surgical incision and epithelial healing and initiates or verifies the fitting for the second eye.

This staggered approach allows the patient to retain functional vision in the first eye with the scleral lens while the second eye is recovering from surgery. Furthermore, it spreads the optical adaptation and lens handling education over manageable intervals, preventing the patient from feeling overwhelmed by bilateral insertion and removal training.

Communication Improves Efficiency

Because we share an electronic medical record (EMR) with most of our optometric team, clinical notes from visit to visit can be read and tracked efficiently. For outside fitting optometrists, we have proactively provided clinical education that helps them through the process. Faxed chart notes with each visit can improve coordination to help with patient outcomes. This shared information includes parameters such as best-corrected visual acuity (BCVA) with spectacles and current contact lenses, contact lens tolerance factors (eg, severe dry eye, handling difficulties, or physical discomfort), high-resolution baseline, and interval corneal topography and tomography.

Slow epithelial healing and exacerbation of prior herpes simplex virus (HSV) corneal disease are the most common reasons that initial surgical recovery might be delayed.¹⁵ Careful attention to dry eye and meibomian gland disease is important if delayed epithelial stabilization occurs. It is not rare for a patient after surgical intervention to present with a herpetic dendrite as we are introducing significant steroid dosage to the healing cornea, and some of these patients may have had prior asymptomatic corneal herpetic disease that is exacerbated by the combination of surgical intervention, ultraviolet light exposure during CXL, or intensive steroid application. Close coordination between the optometrist and surgeon is important during the recovery period.

AS-OCT to Optimize Lens Fitting

High-resolution AS-OCT has shifted postsurgical scleral lens fitting from empirical estimation to improved prediction of fitting changes. The vault dynamics over a cornea that has been physically altered by tissue addition is challenging using a standard slit-lamp optical section alone, and AS-OCT provides improved, noninvasive cross-sectional imaging of the lens-to-cornea relationship across the entire ocular profile. One objective of fitting a postsurgical scleral lens is maintaining an appropriate fluid tear reservoir that provides adequate oxygenation while avoiding mechanical contact with the cornea.^10,11 AS-OCT line scans allow the optometrist to measure clearances with more precision.

The initial target clearance upon lens insertion should range between 200 and 250 μm. Because all scleral lenses settle onto the bulbar conjunctiva over the first few hours of wear, this initial depth allows lens stabilization at a long-term target of 100 to 150 μm throughout the day, mitigating the risk of late-day corneal touch or hypoxia.^8,9,10,11 To preserve the health of vital corneal stem cells, a goal for the transition zone of the lens is a target clearance of 10 μm  to 50 μm over the limbus. AS-OCT highlights areas of regional limbal compression or excessive lift that could induce localized corneal edema or peripheral neovascularization. AS-OCT can be rotated through a 360° radial scan pattern to image how the haptic landing zone sits on the underlying conjunctiva and sclera. It allows the fitter to identify if the edge of the lens is lifting off (inducing excessive tear exchange) or digging too deeply into the episcleral vessels (causing localized compression, vascular blanching, or conjunctival prolapse).

Managing Common Postsurgical Challenges

Midday fogging (MDF) is one of the most common and frustrating issues encountered by scleral lens wearers.^16,17 It is characterized by the accumulation of lipids, proteins, inflammatory cells, and mucous debris within the post-lens fluid reservoir. As this particulate matter builds up, it scatters light, causing a progressive drop in visual clarity that causes the patient to remove, rinse, and reinsert the lens during the day. The structural curvature alterations from ALKRS can exacerbate debris accumulation under the lens. The primary factors associated with MDF are excessive post-lens vault and asymmetric landing zone alignment. A central or midperipheral fluid reservoir that is too deep acts as a stagnant basin. Because the tear exchange beneath a scleral lens is minimal, a large fluid volume traps cellular debris shed from the corneal epithelium, preventing it from clearing. If the landing zone of the scleral lens does not mirror the underlying scleral shape—frequently due to uncorrected scleral toricity—a localized edge lift-off occurs. During each blink, the upper lid applies downward pressure on the lens, causing a micropump effect that forcefully draws the lipid-heavy external tear film and meibomian secretions under the lens edge into the fluid reservoir.

The fundamental challenge of fitting a contact lens over Intacs stemmed from the physical rigidity of the polymethyl methacrylate material.¹⁸ Because plastic cannot blend or remodel into the surrounding human stroma, it creates an abrupt, highly elevated ledge on the corneal surface. If a scleral lens settled over time and made even minor contact with the thin epithelium covering an Intacs segment, the resulting localized mechanical friction could trigger rapid corneal thinning, localized melting, focal scarring, or segment extrusion. To avoid these problems, optometrists had to design complex, multizone reverse-geometry lenses with highly elevated regional vaults specifically tailored to clear the plastic ring margins.

In contrast, ALKRS utilizes biocompatible allogenic donor tissue. Topographically, this results in a smoother, gentler, natural taper rather than an abrupt plastic cliff.

Key Takeaways

Establishing an efficient scleral contact lens workflow following modern surgical KCN management with ALKRS and CXL is one of the most effective ways to streamline and optimize a modern cornea practice. Efficiencies include

• Initiating a staggered transition of 1 to 2 months from the first-eye surgery to scleral contact lens visual rehabilitation.

• Scheduling the second-eye surgery once the first eye can function relatively independently with/without correction or with the first eye’s custom lens.

• Staggering the postoperative healing phase, where the second eye is fit at its own 1 to 2 month timeframe, therefore minimizing overall visual rehabilitation time.  

• Using shared EMR or frequent fax updates to facilitate handoffs and transitions between the surgeon and the optometrist.

• Leveraging high-technology imaging, such as high-resolution AS-OCT and computed tomography and topography, to optimize the mapping of tissue profiles and contact lens clearance depths.

• Identifying postoperative complications such as delayed epithelial healing and HSV infection.

• Troubleshooting clinical issues like midday fogging by adjusting post-lens clearance and using quadrant-specific haptic toricity.

When these clinical elements are synchronized, chair time drops, lens reorder rates decline, and patients benefit from more rapid, comfortable, and stable visual restoration. This collaborative framework demonstrates how structural surgery and specialty optometric care combine to deliver efficiency of care for patients navigating advanced KCN.

References

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9. Rahmatabadi ZD, Naroo SA, Hatami F, et al. The impact of contact lenses on binocular vision in patients with Keratoconus. J Optom. 2026 Jul-Sep;19(3):100610. doi: 10.1016/j.optom.2026.100610

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13. Hersh PS, Stulting RD, Muller D, Durrie DS, Rajpal RK; United States crosslinking study group. US multicenter clinical trial of corneal collagen crosslinking for treatment of corneal ectasia after refractive surgery. Ophthalmology. 2017;124(10):1475-1484. doi:10.1016/j.ophtha.2017.03.052

14. US Food and Drug Administration. Orphan drug designations and approvals: Epioxa HD and Epioxa. Accessed July 12, 2026. https://www.accessdata.fda.gov/scripts/opdlisting/oopd/detailedIndex.cfm?cfgridkey=344911

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David R. Hardten, MD, is a founding partner of Minnesota Eye Consultants, a member of the Unifeye Vision Partner’s board of directors, and an adjunct associate professor of ophthalmology at the University of Minnesota in Minneapolis. He is a consultant for Glaukos and CorneaGen. Reach Dr. Hardten at drhardten@mneye.com.