Seeing the bigger picture in
3 and 9 o'clock staining
Lynette Johns OD FAAO FSLS
Longstanding 3 and 9 o’clock staining with an (R)GP corneal lens may lead to vascularized limbal keratitis (VLK). There are many options to troubleshoot the corneal lens fit to reduce the staining, but sometimes clues exist beyond the cornea.
A 27-year-old female with an 8-year history of keratoconus was referred to our office for evaluation of corneal (R)GP lenses. She reported increasing redness and lens intolerance. Entering visual acuity was 20/25-2 OD and 20/40-1 OS. She recently relocated to a high altitude climate and is a wilderness medical first responder. Her concern was that her increasing lens intolerance may risk her safety in extreme conditions.
The fit of her corneal lenses is shown above (OD and OS respectively). She demonstrated moderate yet significant nasal and temporal corneal staining abutting the tight peripheral curves with minimal edge lift. Additionally, anterior neovascularization led to the edge of heaped epithelium nasally in each eye (below).
We decided to fit both eyes with scleral devices to increase lubrication to the entire cornea and to provide overall lens stability, given her occupation. She responded instantly with an improvement in comfort with the trial devices during the consultation.
The final right device is a spherical, reverse geometry, 19.0 diameter, 660 µm sagittal depth device with a base curve of 8.3 and -2.00 power; she achieved 20/15-1. The final left device is a spherical, reverse geometry device with a diameter of 18.5, 645 µm sagittal depth, 8.3 base curve and -2.00 power. With the left device she achieved 20/15-2.
After two-and-a-half years, she continues to wear the same parameters, and she is comfortable wearing the devices for 16 hours daily without any reports of intolerance. She no longer fears lens instability when working in a harsh environmental setting.
After a recent follow-up evaluation, we took photos of peripheral conjunctival staining outside of the edge of the device (below). The photos are of the nasal conjunctiva in each eye. The pattern of staining suggests exposure-related desiccation. In this case, the main reason we chose a scleral lens was because of her contact lens intolerance and working environment. In retrospect, the conjunctival staining is a potential indicator that no matter how much any practitioner tries to improve her (R)GP fit, in all likelihood the 3 and 9 o’ clock staining would be present because of this exposure that extends to the conjunctiva.
When facing an uphill battle of troubleshooting pesky 3 and 9 o’clock staining, scleral lenses can be an easy way to troubleshoot the problem. Additionally, by lubricating the surface, the staining resolved rapidly and the vessels eventually ghosted. There was no need to employ any topical steroids for this patient.
Dr. Lynette Johns has been the senior optometrist at the Boston Foundation for Sight since 2005.
She is a graduate of the New England College of Optometry where she completed a residency in cornea and contact lenses. She is adjunct clinical faculty at the New England College of Optometry.
Dr. Johns is a fellow of the American Academy of Optometry and a fellow of the Scleral Lens Education Society.