DO YOU EVER FEEL STUCK on a scleral lens design while trying to improve vision for a patient, only to hit a dead end? Try to remember that sometimes, it is not the lens at all.

Many patients seen at my specialty lens-focused office are referred by local ophthalmologists from hospitals or larger group practices. Each one of these patients presents having had a full, dilated comprehensive examination within the past few weeks and has his or her records in hand. All are eager for their lives to be transformed by a magical scleral lens. We recently performed scleral lens fittings for a series of patients who had undiagnosed underlying conditions that limited their best-corrected visual acuity (BCVA) and had gone undetected by the referring offices.

A 28-year-old African American male presented for a first-time scleral lens fitting after corneal cross-linking in each eye within the past three months. Despite experiencing improved vision for the first time in years, he still reported issues with nighttime driving and “flickering lights.” He had mentioned this to his surgeon, but his dilated exam had yielded no conclusion.

When his BCVA seemed to be stuck around 20/30 in his new scleral lenses, a macular optical coherence tomography (OCT) revealed bilateral macular edema (Figure 1). Wide-field retinal imaging also showed a reduction in peripheral retinal vessels. The patient was referred to a retinal specialist and a fluorescein angiography was performed; unfortunately, he was diagnosed with retinitis pigmentosa in addition to his recently treated keratoconus.

Another case was a 55-year-old African American male referred by a corneal specialist to improve his scleral lens fit due to reduced BCVA in his habitual lens (VA 20/100) post penetrating keratoplasty. The patient reported that he had to move his head around to see properly with that eye and that his peripheral vision was decreasing. 

Upon examination, the lens appeared to be fit well and no over-refraction or pinhole showed improvement. A quick undilated retinal exam with a 90D lens showed advanced glaucomatous atrophy of his optic nerve, which was reported as “normal” in the referring records. The patient was diagnosed with advanced glaucoma (Figure 2), and this, not his scleral lens, was limiting his BCVA.

Key abnormal symptoms to keep in mind when evaluating irregular cornea patients include:

• Increase in flashes/floaters
• Having to move one’s head around to improve vision
• Reporting missing spots in one’s vision
• Color desaturation
• Ability to see only half of a line of VA clearly

In summary, when facing challenges in optimizing scleral lens fits, it is important to examine the posterior segment of the eye. Specialty lens referral offices should consider adding wellness OCT, ultra-wide-field screenings, and/or dilations to their protocol for new fits, even when a patient presents with recent records from even the best of our colleagues and insists he or she was just evaluated. This protects the specialty lens fitter and the patient from the consequences of missed diagnoses.

Unfortunately, the vision complaints of patients with irregular corneas are often dismissed due to the mistaken belief that their reduced vision is due to corneal issues and that scleral lenses will remedy all of their problems. Don’t forget to look through the “window” at the big picture.