International Newsletter and Forum on Rigid Gas Permeable Contact Lenses, Corneal Shape, Health and Vision
 August 2012
In This Issue
Column
Scleral Lens Case Series
Multifocals
Orthokeratology
Vernal Keratoconjunctivitis & Keratoconus
I(n)-site-the-practice
Agenda
Join Our Mailing List
  

(advertisement)
Column
A Learning Curve

The recent popularity of scleral lenses really has helped them reach many more patients who could benefit from them compared to just a few years ago. But what about the chair time, follow-up visits and lenses needed for a scleral lens fit? Although there is a learning curve for sure, I think many people would be surprised by the scleral lens charts of many experienced fitters. Muriel Schornack et al recently reported at ARVO (program#4715) that completing the scleral lens fitting process required an average of 3 visits (range 2-6 visits) with an average of 1.4 lenses (range 1-3 lenses) ordered per eye. All patients had ocular surface disease and all (185) eyes wore scleral lenses successfully at the conclusion of the fitting process. Scleral lens fit was determined by using a diagnostic lens set. The vast majority of eyes were successfully fitted with the first lens ordered, and the fitting process was completed in 2 or 3 visits in most patients. In Eye & Contact Lens, Mariana Pecego et al reported on 107 scleral lens fits in keratoconus and found that a mean of 3.2 lenses were used, ranging from 1 to 8, and the mean return to clinic was 6.2 times in a period of 3 to 17 months. For more clinical information about sclerals (and curves): see also the next item in this newsletter. 

Eef van der Worp

Scleral Lenses
New Book on the Block

On the Pacific University website, A guide to scleral lens fitting is available to anyone interested in scleral lenses. It provides an overview of what scleral lenses are as well as terminology and basic understanding of scleral lens design and fitting. Recently, a Scleral Lens Case Report Series was added to the site that contains 30 scleral lens fitting, an initiative of Microlens of the Netherlands to which 13 experienced scleral lens fitters from the Netherlands and Belgium contributed. Ten of the cases presented are devoted to 'indications' (chapter two), ranging from ectasia to ocular surface disease. Ten more cases (chapter three) describe 'fitting tips,' from the more obvious ones related to scleral lens 'sinking,' for instance, to a description of low vision and hand-painted scleral lens fittings. But a technically successful lens fit alone is not sufficient for successful scleral lens wear. Several factors, including hygiene, proper lens care, good instructions and managing lens handling issues, play a crucial role in this process. Chapter four consists of ten cases covering topics related to management and problem solving. The book can be downloaded as a PDF or can be read online at the Pacific website (see link below).

Multifocals
Refitting Soft Multifocal Patients into (R)GPs

Phyllis Rakow in Contact Lens Spectrum asks the question of what to do 'When soft multifocal wearers with center-distance add powers complain that they are unable to attain satisfactory near vision...or distance vision.' The problems are even larger when corneal astigmatism and/or amblyopia are present. 'Have the conversation,' she suggests, about previous lens wear and visual needs and bring up the option of (R)GP multifocals. In the author's practice, if presbyopic patients express frustration with their current soft lenses or if they demonstrate limitations with their soft multifocals, the time is right to present the advantages of (R)GP multifocals. 'While it is not uncommon for these patients to have been told that they will have to live with their frustrations because that is the best that can be currently achieved with soft multifocals, we carry the conversation to the next level,' Phyllis states. See also the 'I(n)-site-the-practice' item below in this newsletter for a case report on the same topic. 
Orthokeratology
Corneal Reshaping in Kids: Risks vs. Benefits

Jason Jedlicka in Review of Cornea & Contact Lenses reviews the literature and combines this with his clinical knowledge to see where we are with orthokeratolgy, especially when it comes to children. 'We all want what is best for our children. Good vision and ocular health are important aspects of our children's lives,' Jason states. 'To be able to provide vision correction that is convenient, safe and effective at slowing the deterioration of their vision over time is something most of us would want for our children who require vision correction.' According to the author, corneal reshaping seems to be able to meet these goals. If done carefully, the risks can be minimized, while the benefits may be maximized.
Scleral lenses
Vernal Keratoconjunctivitis & Keratoconus
 
bridge
Vernal keratoconjunctivitis is a bilateral allergic condition characterized by repeated episodes of inflammation of the conjunctiva and cornea. It may cause severe itching, photophobia and mucus discharge. The condition is seen more commonly in keratoconus. A case report series by Varsha Rathi et al in India published in Eye & Contact Lens showed that fluid-filled scleral lenses in vernal patients with keratoconjunctivitis and keratoconus improved vision and helped to maintain the health of the ocular surface.

I(n)-site-the-practice   
The Presbyopic Astigmat (or the Astigmatic Presbyope)

Presbyopia combined with a high amount of astigmatism is often recognized as a challenge in contact lens practice. This is especially true if the astigmatism is oblique. Translating (R)GP designs generally offer fantastically clear images for distance and reading purposes. However, if the reading portion rotates temporally while the patient is reading, visual acuity will be reduced and patients often complain about seeing shadows while they read. Our patient was a 48-year-old Caucasian female with a high amount of oblique astigmatism. She has worn (R)GP lenses 22 years. During the last few years, she has suffered from increased presbyopia and complained about difficulty with reading. Topography OS showed astigmatism of 3.60D at 30�. This case report will concentrate on the fitting of a translating (R)GP lens design by Michael Baertschi, Michael Wyss, Simon Bolli and Marc Fankhauser from Bern (Switserland). 
Click here for the full report.
Erratum

The July issue of I-site newsletter referred to a poster by Vinod Maseedupally et al (ARVO program # 4714) regarding orthokeratology and corneal astigmatism. It was mentioned that 'The treatment zone was decentered in both groups, with greater decentration in the group with low (≤1.50D) compared to the group with moderate (>1.50D) amounts of corneal toricity.' It should have said that more decentration was found in subjects with moderate corneal toricity (>1.50DC) than subjects with low corneal toricity (≤1.50D). Apologies for the error.
International Agenda
Upcoming Events
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: [email protected].