Specialty lens fitters commonly encounter patients who have undergone corneal surgeries; or, conversely, they have referred patients for surgery. It is important to understand from a surgical standpoint the time frame regarding when it is safe to return to or to initiate contact lens wear. For specialty lens fitters, the most common of this patient population are those who have undergone either a corneal transplant or corneal collagen cross-linking (CXL).

Post-Corneal Transplant Patients

For patients who have undergone any form of corneal transplant, the post-surgical care is arduous and lengthy due to healing time and suture monitoring. In 2004, Weitharn reported that the average time frame for fitting after corneal transplant was 18 months, but this ranged from eight to 33 months. Contact lens fitting may be initiated in as little as three months if complete healing of the donor-host complex has been determined.

Sutures are the main reason for the timing, as surgeons will follow their own removal algorithm. The removal of sutures greatly impacts the graft shape and topography. Furthermore, surgeons may elect to perform additional limbal relaxation or refractive surgery, which can impact both graft shape and refractive outcomes and can further lengthen postoperative healing time (Verdier, 2011; Gruenauer-Kloevekorn et al, 2005).

In addition, postoperative topical medication dosing schedules, the exact type of allograft technique utilized, and/or the baseline corneal diagnosis that necessitated keratoplasty can also affect the postoperative optical rehabilitation via contact lenses. Therefore, multidisciplinary communication with corneal surgeons and patients can be essential in determining the exact timing for when the contact lens rehabilitation process should be initiated (Chang and DeLoss, 2018). Once a patient is deemed suitable for contact lens fitting, it becomes critical to fit a lens that will minimize mechanical trauma to the donor tissue. Both mechanical and physiological stress can increase the risk of infection or lead to rejection (Szczotka and Lindsay, 2003).

Post-CXL Patients

For CXL, the exact timing to initiate contact lens fitting or to resume lens wear has not been formally reported in the literature. Additionally, the percentage of patients who require contact lenses after CXL has yet to be studied. However, it is important for eyecare providers to be aware of current standards.

Following CXL, the recovery is not consistent; corneal remodeling and thinning can take place, and haze can develop. These changes can take place over a six-month time period or longer (Greenstein et al, 2011; Greenstein et al, 2010). The type of procedure, such as epithelial-on versus epithelial-off, can also impact healing time and results. Studies on the impact of CXL show that the cornea flattens by 2.00D on average, with more severe cones having a greater rate of flattening compared to less severe cones (Caporossi et al, 2010). This flattening will significantly impact both the fitting relationship and refractive outcomes; furthermore, it is important to know that flattening can continue for up to 12 months, with the most significant flattening occurring within three-to-six months and gradually lessening over the remainder of the 12 months (Hersh et al, 2017).

Clinically, at my institution, ophthalmologists have referred patients who have undergone CXL in as little as one month, but most commonly they refer patients at three months. This decision is primarily determined from keratometry and vision as well as from supporting evidence-based publications on the rate of corneal flattening. Some ophthalmologists currently prefer to wait until six months; however, we still await additional publications to establish clinical guidelines.

Corneal haze and other adverse events typically remain minimal after CXL, and close monitoring by eyecare professionals and treating surgeons often yields the best clinical outcomes. CLS

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