A 52-year-old female came in for a comprehensive eye examination. She presented wearing glasses and noted that her vision wasn’t very good with them. She reported that the vision was better with her soft toric lenses, but it was still difficult for her to see things clearly even with the contact lenses. She also reported that she had tried to undergo laser-assisted in situ keratomileusis (LASIK) a few years ago, but when she went in for her assessment, they couldn’t proceed with the surgery because of something that they saw on the cornea.
Her manifest refraction was OD –7.00 –2.50 x 120, 20/25 and OS –7.00 –1.50 x 075, 20/25. Her contact lens prescription was OD –6.50 –1.75 x 110, 8.7mm base curve, 14.5mm diameter, 20/20– and and OS –6.50 –0.75 x OS –6.50 –0.75 x 070, 8.7mm base curve, 14.5mm diameter, 20/20–.
An over-refraction performed over the lenses was plano for both eyes. All comprehensive examination findings were healthy and normal. Topography was remarkable for mild keratoconus. A pachymetry map of the cornea showed thinning in the region where steepening was noted with the topographer.
Poor visual quality is a common complaint that patients will have without necessarily describing it as poor visual quality. They will simply say that their vision seems “blurry” or “not as good as it should be.”
Unfortunately, with a standard Snellen acuity chart, it is difficult to identify these individuals without a very careful ear. Although measuring Snellen acuity is the standard, we know that the real world’s visual stimuli vary significantly from the Snellen chart. Oftentimes, the real world isn’t as high-contrast as black letters on a bright white background are. As such, Snellen acuity is only part of the story when it comes to understanding visual outcome.
A number of ocular conditions can leave our patients with poor visual quality despite 20/20 visual acuity. In this patient, it was mild keratoconus that resulted in her poor visual quality.
We feel that educating patients regarding their options is the next appropriate step in such a case. In this instance, we had the option of continuing with the patient’s current contact lenses or refitting her in a specialty lens designed to improve visual quality for such patients.
We had her return for a specialty lens fit. Initially, we fit her in a small-diameter GP lens with good visual results. Unfortunately, the patient was concerned with the initial lens comfort.
We then proceeded with a scleral lens that provided the vision she obtained with her small-diameter GPs with significantly less initial lens awareness. The lens was ordered with appropriate central and limbal clearance along with adequate scleral landing zone characteristics.
At dispensing, the vision was OD 20/20 and OS 20/20. The patient was instructed on proper lens application and removal, and she returned for follow up in one week. At the follow-up visit, the patient was excited to share how much better her vision was. She was wearing the lenses successfully on a daily basis.
Visual acuity measurements will frequently not provide the complete picture when considering patients’ vision and why they experience blurred vision with 20/20 acuity. It is incumbent upon us to truly support our patients’ desire to obtain better vision and to provide appropriate answers on why their vision may not be at the level they feel it should be. If simply obtaining 20/20 vision is the new norm, we don’t want to be normal. CLS