“When you change the way you look at things, the things you look at change.” – Wayne Dyer
Eyecare practitioners (ECPs) are fortunate to work with so many passionate consultants in our industry. On a daily basis, I value the information and advice that consultants provide. For this month’s Scleral Lens Monthly, I asked for the most important information to obtain when fitting scleral lenses—from a consultant perspective. So many valuable tips were received. Here are a few of them.
Many responses were about scleral lens comfort. After applying a lens, ask patients how the lens feels upon application and again after the lens has settled for 30 minutes. ECPs should note what time the lens was applied to specify how long the lens has been on the eye prior to evaluation. After the lens has settled for 30 minutes, evaluate the lens in each zone—apical vault, midperipheral clearance, limbal clearance, and landing zone. If two eyes are fit and one lens is more comfortable than the other is, it is beneficial to compare the comfort between the right and left lenses.
To confirm that a lens is stable after settling, manually rotate the lens 90º and observe whether the lens lands in the same or in a different location. If the lens is stable, it should return to the original position quickly. It is preferable to have a stable lens prior to adding cylinder or multifocal optics, because changes in parameters can affect lens rotation. Note the markings on the lens to identify flat and steep meridians. Documenting edge lift, blanching, or impingement to make adjustments is beneficial. Multiple consultants prefer to evaluate the edge with the slit lamp rather than with optical coherence tomography (OCT). According to one consultant, although OCT is helpful, an image of the edge profile may not be accurate, because if the lens pushes into the conjunctiva in peripheral gaze, then the lens profile thickness may appear excessive in peripheral gaze. However, OCT measurements in primary gaze of the central apical clearance are valuable and accurate. Other helpful tools are corneal topography or tomography to evaluate corneal elevation. In addition, scleral mapping can assist practitioners to determine the landing and peripheral profile of a scleral lens. Sending pictures or videos is also helpful.
Conjunctival prolapse refers to perilimbal conjunctival tissue that is drawn under a scleral lens. Inferior-temporal lens decentration, a thicker fluid reservoir, excessive conjunctival tissue, conjunctivochalasis, and loose conjunctiva are factors that can contribute to conjunctival prolapse. If conjunctival adherence, pannus, or corneal neovascularization are present, lens modifications are needed. Management of conjunctival prolapse includes reducing limbal reservoir thickness, improving landing zone alignment, or incorporating a fenestration to relieve suction. Consultants advise practitioners to monitor, and not chase after, conjunctival prolapse. One tip is to take a picture of the eye without the lens and then take another picture one month and then six months later to reveal whether neovascularization is present. Keep in mind that good vision, comfort, and ocular physiology are of the utmost importance.
Acknowledgement: Thanks to the scleral lens consultants—Connie Adam, SynergEyes; Manny Carvalho, BostonSight; Troy Miller, Acculens; Dede Reyes, ABB Optical; and Kelsey Roberts, Valley Contax—for their contributions to this edition of Scleral Lens Monthly.
Dr. Barnett is a principal optometrist at the University of California Davis Eye Center, specializing in anterior segment disease and specialty contact lenses. She is the past president of the Scleral Lens Education Society. She is an advisor to and/or has received honoraria or travel expenses from AccuLens, Alcon, Alden Optical, Allergan, Bausch + Lomb, Bruder, Contamac, CooperVision, EveryDay Contacts, Johnson & Johnson Vision, Ocusoft, Paragon Bioteck, RaayonNova, ScienceBased Health, SynergEyes, Tangible Science, and Visioneering Technologies.