Aphakic Scleral Contact Lens
Gregory W. DeNaeyer OD FAAO FSLS
Patients may lose the natural lens of their eye secondary to trauma or surgery. For patients who have bilateral aphakia, glasses are not practical because the high-plus spectacle lenses are not ideal from an optical or cosmetic standpoint. Patients who have unilateral aphakia can’t wear glasses secondary to anisekonia. However, aphakic contact lenses, either soft or (R)GP, have the potential to provide patients with excellent vision.
A 54-year-old patient with aphakia of the left eye reported for specialty contact lens evaluation. The vision of the patient’s right eye was count-fingers, but his left eye measured 20/30 with a corneal (R)GP lens. The patient complained of recent irritation with his aphakic contact lens. Slit lamp examination showed an inferiorly decentered corneal GP lens that had no movement (Figure 1). An impression ring where the GP lens was binding was observed after lens removal (Figure 2). After discussing lens options, I fit him in a silicone hydrogel aphakic soft lens. The patient complained of blurry vision with the soft lens, so an attempt was made to refit him in a corneal GP lens. Unfortunately,
the newly fit corneal GP lens also tended to sit low and bind to the cornea. The patient was finally successfully fit with a mini-scleral (R)GP lens: Blanchard MSD (Boston XO2-with UV filter) 4.2(S), 15.8mm diameter, +15.75D (Figure 3). The patient was able to achieve 20/30 vision with a (R)GP mini-scleral lens that is centered without corneal binding.
Contact lenses are the best refractive option for patients who have aphakia. In particular, (R)GP lenses offer patients superior optics. Corneal (R)GP aphakic lenses can be challenging to fit secondary to increased lens mass that can cause inferior lens decentration. In this case example, not only did the lens decenter, it also exhibited unacceptable lens binding. A scleral has the advantage of improving centration and avoiding the consequences of an ill-fitting corneal (R)GP lens. Using a hyper-Dk material is recommended to maximize oxygen transmissibility for aphakic lenses that have increased center thicknesses. Another important material consideration is UV protection. Boston XO2 for instance, as used in this case, can be ordered with and without UV filter. UV-protection is key in aphakic eyes, as the natural filtering capacity of the crystalline lens is no longer present.
Greg DeNaeyer is a 1998 graduate of The Ohio State University College of Optometry. He completed a hospital based residency at the Columbus VA Medical Center. Greg joined Arena Eye Surgeons in 1999 and is currently the Clinical Director. His primary interest is specialty contact lenses.
Greg is a boardmember of the Scleral Lens Education Society and is a Fellow of the American Academy of Optometry. He is a contributing editor for Contact Lens Spectrum and a contributor to Review of Cornea and Contact Lenses and Optometric Management. Currently his primary research is focused on profilometer designed scleral contact lenses, scleral lenses that correct higher order aberrations, and topical drug delivery devices. He has consulted for Visionary Optics, Essilor, Inspire Pharmaceuticals, B+L, and Aciont.