Penetrating keratoplasty (PKP) can be necessary for some cases of corneal scarring or when there is a loss of structural integrity of the cornea. Patients who have Stevens-Johnson syndrome, ocular cicatricial pemphigoid, or chemical injury can have an increased risk of failure secondary to the severity of their condition. For these cases, a surgeon may elect to not perform a PKP either as a primary or a repeat surgery, because the risk of failure is too high.

An alternative option is for a patient to have an artificial corneal transplant. The most common of these devices consists of a front plate, which has an optical stem, and a back plate. The plates sandwich a corneal graft that is then sutured to a patient’s eye. These devices require lifelong use of antibiotics to prevent infection and a bandage lens, typically a soft lens, that protects the grafted cornea from desiccation (Thomas et al, 2015; Nau et al, 2014). The bandage contact lens can also incorporate power as needed to improve visual acuity.

Case Report

A 41-year-old patient reported for specialty contact lens fitting of his left eye. Twenty years prior, he suffered a bilateral chemical injury. He initially underwent a PKP for each eye, but they both eventually failed and were each replaced with a Boston keratoprosthesis. The patient’s left eye was aphakic and had a tube shunt to control glaucoma; however, the shunt was recently removed secondary to hypotony.

He was wearing bandage soft contact lenses on both eyes. The right lens was a monthly replacement silicone hydrogel that provided 20/150 vision and an adequate fit. The left 16mm soft lens (Figure 1) had poor on-eye stability, but it did allow him to see 20/50. Corneo-scleral topography measured significant scleral irregularity. These measurements were used to design a free-form scleral lens that successfully fit his anterior ocular surface (Figure 2), providing 20/40 visual acuity.

The patient was instructed to remove the scleral lens nightly so that he could continue his topical ophthalmic medicines. Unfortunately, he had initial difficulty with lens handling and had a brief infection that was successfully treated; due to these circumstances, he is wearing his custom soft lens for now.

Discussion/Conclusions

A monthly replacement contact lens can successfully bandage a keratoprosthesis, as is the case with the patient’s right eye. However, anterior surface irregularity can lead to failure with molded or customized soft lens options. This can especially be the case when a patient has undergone glaucoma surgery. Although soft lenses are still generally preferred, scleral lenses can provide protection, continuous hydration, and optical correction.

Continuous wear (off-label) is standard practice, perhaps instructing patients to briefly remove their scleral lens for cleaning and drop instillation; but every case is unique (Carrasquillo, 2021; Sindt, 2021; Gelles, 2021). Be prepared for setbacks, as was the case with this patient. CLS

For references, please visit www.clspectrum.com/references and click on document #304.