Contact lens material technology has made significant advancements in the last few years, and now have higher-Dk materials which have been impactful for a variety of patients. One example of when oxygen transmission becomes particularly important is in the case of patients with a history of penetrating keratoplasty. 

Case Description

A 49-year-old woman presented for a scleral lens refit. She had prior history of wear after a penetrating keratoplasty 12 years earlier for keratoconus. Following surgery, she was left with an irregular pupil OS and a highly asymmetrical graft. Her right eye remained moderately steep from keratoconus with irregular astigmatism, so she found visual improvement with both eyes through the use of scleral lenses.  

While her VA was 20/40 OD and 20/60 OS, she reported several problems with the prior lens fit OS. She would get redness and irritation in the eye, along with blurred vision that would last after removing the lens when she would feel the need to “take a break from it.”  Examination of the habitual OS lens showed touch around the graft host junction and uneven alignment along the scleral landing edge. Her cornea also showed some vertical striae in the center of the graft after wearing her habitual lens for several hours prior. Pachymetry showed signs of edema.

Diagnostic refitting was attempted, but she still showed touch over the superior nasal graft host junction. The decision was made to measure the eye’s scleral profilometry (Figure 1) and create a free-form lens from the data using Optimum Infinite (Contamac), a hyper-Dk material to reduce risk of edema as experienced in her habitual lens.  

The free-form lens vaulted the entire cornea with the new design and showed an even alignment around the edges (Figure 1). The patient was also happy with improved vision, seeing 20/25 OD and 20/30 OS. The lenses were dispensed, and she returned 1 week later for post-settling evaluation. After wearing the lenses 4 hours prior, the cornea was still fully vaulted over the graft host junction and there were no signs of blanching along the edges, nor sign of stromal striae. The patient returned for a final follow-up 1 month later where she reported that she was able to wear her scleral lenses the full length of a day and was no longer experiencing redness or blur.

Discussion

This patient was having some success with visual improvement through scleral lenses after her cornea transplant but was experiencing edema. She was desperate for a solution to be able to continue wearing a lens on her left eye to retain vision. Her previous material had Dk of around 100, so a more breathable material was able to decrease the risk of edema.

Material selection and Dk consideration is important to ensure the patients are able to safely wear lenses without the risk of edema or other complications. Through the use of hyper-Dk materials, some patients can return to full daily wear. 

Nicholas Gidosh, OD, is chief of contact lens services and assistant professor of optometry at Salus University in Philadelphia. He is a fellow of the American Academy of Optometry. He is a paid consultant for Acculens and Bausch + Lomb Specialty Vision Products.