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International Newsletter and Forum on Rigid Gas Permeable Contact Lenses, Corneal Shape, Health and Vision |
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Handling F(r)ee
 Something that really annoys me is when you book something online (a ticket, a trip), and all of the sudden at the end a 'handling fee' arises out of nowhere. Wasn't I booking this online to avoid the administration at the other end? The only time when a handling fee actually would be appropriate is when it comes to instruction for scleral lens insertion and removal. Teaching handling should actually not be free. It consumes a lot of time, and it is absolutely instrumental in the scleral lens fitting process. In fact, the handling may be more important than the fitting itself. Larger practices actually prefer to train staff specifically for this. If you can get staff passionate about scleral lens handling, then it could be the difference between success and failure. Much more annoying than a handling fee is a perfect, technically well-balanced scleral lens fit on a patient who fails to be able to handle it, many eye care practitioners tell me. A tip that may help to use little rubber rings (used for orthodontic purposes), referred to previously in this newsletter. They are clean, sterile - and provide just the right amount of stability on the finger for a top-heavy, fluid-filled scleral bowl. Alternatively, as proposed by Langis Michaud from the University of Montreal (CA), a minor indentation of the index finger by the dull end of a pen or pencil (or a sterile alternative) could give just the right amount of indentation to balance the lens on the tip of the finger. In other words, perform a small amount of orthokeratology of the finger - to support scleral lens insertion.
Eef van der Worp
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Complicated?
Two of the questions many of us regularly hear regarding sclerals, and rightfully so, are: is this safe, and what are the long-term effects? A recent paper from the University of Houston provides a good overview of the literature related to the topic of complications and fitting challenges associated with scleral lenses. Midday fogging, epithelial bogging and associated inflammatory responses all seem to be potentially related to tear exchange beneath the lens, and they seem to be the most challenging complications, according to the paper. These are likely to be multi-factorial in nature. Fortunately, infection rates do not appear to be greater in scleral wearers than in other contact lens modalities, and we have yet to observe acute, vision-interfering complications related to oxygen deprivation. The paper emphasizes the need for more research in the field. Regarding the complication rate - what makes it a bit complicated is that we are typically dealing with challenging and/or diseased eyes. So when it comes to scleral complications, it is not always simple. Luckily, there is a pretty long track record with scleral lenses: which looks good, when in the hands of the right scleral lens fitter.
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Scleral Lens Fitting: Once Rare, Now Routine?
As proof of the fact that sclerals are still gaining momentum, the entire April edition of Review of Cornea & Contact Lenses is devoted to the modality. Articles cover topics including 'Sclerals: Easy as 1-2-3': according to Mile Brujic and Jason Miller, it is instrumental to 1) make sure the scleral lens clears the central cornea, 2) respect the limbal region of the cornea and 3) monitor the scleral landing zone. 'Happy Landings' by Robert Ensley and Heidi Miller, talks about incorporating toricity into scleral lens designs and how this may improve your fitting success. Langis Michaud from the University of Montreal covers the 'Rare vs Routine' topic from his standpoint. Marsha Malooley and Jeffrey Sonsino take on 'Solving Problems with Specialty Lenses'. Chandra Mickles and Melissa Barnett 'go deep' with scleral lens troubleshooting - covering everything from discomfort to complications. Stephanie Woo offers great practical tips and directs readers to useful resources, both for 'first-timer' and more advanced fitters. According this article, proper education prior to regular lens wear can save you from unnecessary phone calls or extraneous patient visits, and it can save your patients from complications down the road. Additionally, investing time and energy into scleral lens education can help you further gain patient trust and respect, potentially leading to more referrals. Everyone loves to feel special, and helping patients feel cared for can create patient loyalty and a great relationship with their eye care practitioner.
Photo: Gustav Pöltner (A) ©
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Hypoxia in Scleral Lens Wear
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Anterior & Posterior Corneal Changes
 Vincent et al looked at hypoxic corneal changes following eight hours of scleral lens wear. They examined the change in corneal thickness and posterior curvature following 8 hours of mini-scleral lens wear (Dk=100)
using Scheimpflug imaging. They observed a small but highly statistically significant amount of edema following 8 hours of mini-scleral lens wear over the central 6 mm of the cornea, after accounting for normal diurnal fluctuations (mean ± standard deviation percentage swelling 1.70 ± 0.98%, p < 0.0001). Posterior corneal topography remained stable following lens wear. In conclusion, they state that while a small amount of corneal swelling can be induced following 8 hours of mini-scleral lens wear, modern high-Dk mini-scleral contact lenses that vault the cornea do not induce clinically significant corneal edema or hypoxia-related posterior corneal curvature changes during short-term wear. Still, longer-term studies of compromised eyes (e.g. corneal ectasia) are required to determine the optimum lens and fitting characteristics for safe scleral lens wear to minimize corneal hypoxia. Photo: Oliver Gubler (CH) ©
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Sclerals: Dry Eye & Lens Care
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Its Clear!
A 64-year-old white female was referred for a contact lens consult from her primary care optometrist. The patient had a history of bilateral corneal transplants about 15 years prior due to keratoconus OD and OS. She was fit into a hybrid lens OS 4 years prior, but the left eye showed beginning signs of neovascularization, and she was referred for a second opinion and possible refit. After reviewing the different options with the patient, she opted to try a scleral lens.
The benefits of the scleral lens for this patient include: the cornea stays clear (as opposed to the bearing with the hybrid lenses), further neovascularisation development is suspected to stop (and potentially reverse, resulting in clearing of the blood vessels) and good visual acuity (providing clear vision to the patient). All clear!
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I-site is an educational newsletter that is distributed on a monthly basis and provides an update on rigid gas permeable related topics (scientific research, case reports and other publications worldwide). I-site is objective and non-political. Its editor Eef van der Worp, optometrist, PhD, FAAO, FBCLA, FIACLE, FSLS is a lecturer for a variety of industry partners, but is not related to any specific company. Please contact us at: i-site@netherlens.com.
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