Anterior segment A-OCT in monitoring low grade limbal ischemia and custom scleral lens design aiming the elimination of the clinical findings

Lefteris Karageorgiadis, BScOptom^1, Nikos Vasileiou, BScOptom², Leonidas Mavroudis, MD³, Marina Banteka, MD³

1. EYEART Fitting center, Thessaloniki, Greece, 2.EYEART Laboratories, Thessaloniki, Greece, 3.   LMVision clinic, Thessaloniki, Greece

Free Papers I | Kassandros Hall | 21/10
Thursday, Oct 21, 2021
3:30 PM - 5:00 PM
KASSANDROS HALL

The 35th International Congress of the HSIOIRS (Hellenic Society Of Intraocular Implant and Refractive Surgery) will take place at “Ioannis Vellidis” Congress Centre in Thessaloniki, on 21-23 October 2021.

Goal:

The preference of Scleral contact lenses (SCL) has been significantly increased by practitioners and patients, as they provide a stable optical surface in challenging cases of irregular astigmatism, without being in contact with the corneal surface. Nevertheless, non-optimal fitting and prolonged wear can cause circulation blockage in blood vessels, leading to possible corneal surface degradation and limbal ischemia. OCT-Angiography, well established for the posterior segment monitoring and diagnosis, may also be used to monitor blood vessel circulation of the conjunctival and scleral region on the anterior segment. Furthermore, angiography driven lens modifications can also be used for restoring reduced circulation.

Method:

Two cases of SCL wearers with reduced time for comfortable wearing (4-6 hours daily) underwent OCT-Angiography to capture conjunctival and scleral blood vessel circulation. Specially modified parameters have been used, to focus on the anterior segment. Based on the findings, new lenses were designed with custom scleral landing zone geometry, aiming to relieve and restore more fluent circulation. The same monitoring procedure is performed with the new SCL.

Results:

Substantial relieve of circulation was achieved and the comfortable wearing time has been doubled. A follow up clinical examination, 14 and 30 after the modified fitting, showed normal anterior surface physiology.

Conclusions:

Anterior segment OCT-Angiography’s technology can help in monitoring blood vessel circulation in areas that the SCL is supported, enabling an ameliorated custom design of the lens, that could minimize or even eliminate clinical findings, and increase patient comfort. The usability and repeatability of the OCT-Angiography can contribute in everyday clinical diagnosis and monitoring.

It is now common knowledge that the blue light emitted by the screens of our devices is harmful to our health. However, the modern way of life makes it impossible to avoid them, greatly increasing the time we spend daily exposed to them. According to research, the average time users spent on their mobile phones in 2020 was between 3-4 hours a day. At the same time, those who work on a computer, spend another 8 hours a day in front of a screen. In total, this means about 12 hours a day of exposure to Blue Light, not counting activities such as gaming, watching videos or TV, the transition to e-books, studying for school or university etc., which are part of most people's daily routines and require the use of these devices.

What exactly is Blue Light?

The visible spectrum of light includes different shades (red, orange, yellow, green, blue and violet), each of which corresponds to different wavelengths and emitted energy. The rays at the red end of the spectrum emit longer wavelengths and less energy, while the blue-violet light rays emit shorter wavelengths and more energy (electromagnetic radiation). Thus, blue light has almost twice as much energy as red light at the other end of the visible spectrum. These waves penetrate deep into the eye and long-term exposure can cause severe damage to the retina.

How to protect yourself from Blue Light

To protect your eyes from the Blue Light of the screens, you can follow these tips:

• Use a blue light filter on your mobile phone or computer. Some phones already have it built-in (and it can be turned on and off whenever you want). Alternatively, there are apps that add this filter to smartphones or tablets. There are also special screen protectors that filter blue light.
• When working on the computer, make sure your eyes rest. Every 20 minutes look away from the screen (about 6 meters - for example outside the window) for 20 seconds.
• Use artificial tears to moisturize your eyes. Constantly looking at the screen, especially if we are focused working, we often do not blink as much as we should. This results in dryness, irritation and pain.
• If you wear prescription glasses, add the special coating that filters the blue light to the lenses. But even if you do not use prescription glasses, you can choose a frame that suits you and add the special blue light lenses, without adding degrees of myopia.

After using the "computer glasses" as many people call them, there has been a reduction in complaints of visual fatigue, eye irritation, headaches, difficulty concentrating, dizziness, dry eyes and sleep disturbances - symptoms attributed to long hours of use digital devices. They are ideal for children who attend online classes or play electronic games, for adults who use computers at their job, for those who read on computers or tablets, and for those who spend their free time watching movies and series.

Blue light glasses are considered the easiest and most economical solution to improve our quality of life and to relax our eyes. As an added bonus, they also allow us to finally wear stylish glasses without having myopia, presbyopia or any other visual problems.

Glasses are the standard solution for people with presbyopia who want a better vision. But now, with the new technology of multifocal lenses, it is not the only one. Multifocal lenses operate in concentric circles in front of our eyes, so that all the gradations in our visual specter are stable. This means that with the use of multifocal lenses you will have optimal vision at all distances - near, far and in between. Unlike multifocal glasses, they do not have areas with peripheral optical aberrations, so they are very easy and quick to get used to.

The modern multifocal contact lenses introduced this year, have significant advantages compared to their ancestors:

• Personalized design for each different degree of presbyopia.
• Correction of astigmatism with precise correction of prescription grades
• Personalized application parameters of lens curvatures, offering maximum comfort and quality of vision.

These revolutionary options make the new OMEGA 6 multifocal contact lenses the ideal solution for anyone who needs to correct different degrees of near and far vision.

For more information on how Multifocal contact lenses work or about their application, make an appointment with us by calling +30 2310 282285 

A study conducted at Ohio State University by Jennifer Swingle Fogt and colleagues, showed that visual performance using multifocal glasses and contact lenses is statistically the same.

The study involved 24 patients who were tested for response time, peripheral visual field perception, hand-eye coordination, and dynamic visual acuity. Performance tests were conducted using multifocal glasses and later on, using multifocal contact lenses. The patents were also given some days for adjustment between each solution.

After analyzing the results, the researchers stated that they now prefer the use of multifocal contact lenses, rather than multifocal glasses.

For more details: Ref: 1367-0484 / © 2021 British Contact Lens Association

For more information on how Multifocal contact lenses work or about their application, make an appointment with us by calling +30 2310 282285 

Keratoconus is an ocular condition in which the normal structure (shape) of the cornea gradually thins, creating a conical type of cornea and resulting in a gradual increase in astigmatism. It is a condition that usually occurs in the ages of 15-20 years.

People who have keratoconus, depending on the type of keratoconus and its extent, have very different needs when it comes to its treatment. Some can achieve very good vision with the use of simple glasses of small degrees, some can mainly see better with one eye, some achieve good vision only with the use of contact lenses and with wearing their auxiliary glasses the possibilities are significantly limited.

Therefore, if we want to help and make life easier for the people close to us with keratoconus, we should consider the following:

• People with keratoconus require some extra time during the day to apply their contact lenses. The use of special contact lenses should not be continuous for many hours (maximum 14-16 per day), so a person with keratoconus should be given the required time for breaks, in order to rest their eyes.
• You need to plan some activities differently, based on their needs. Activities that require a lot of detail or night driving can be especially demanding for people with keratoconus. Therefore, you should plan work shifts, travel curriculums, lighting conditions and workplace ergonomics, according to their needs.
• People with special contact lenses, recommended by specialized eye health professionals, have better vision. Patients with keratoconus are often provided with different correction prescriptions, which have significant differences. This is perfectly normal. Since their astigmatism is asymmetric, there are many different degrees in the patient's visual specter, and only some of them can be corrected with glasses. In addition, the optical diaphragm of our eye, the pupil, changes its diameter based on the current lighting conditions. This fact alone could result in different prescriptions. Better vision can only be achieved with the use of special contact lenses (ex. Delta Conus, Epsilon, Dualascon). Optical health professionals can choose the best possible solution for the needs of each individual.

You can also make an appointment with our specialists, who can help you with the application of such lenses.

The most common way to improve your vision is with the use of glasses that are for myopia, presbyopia or multifocal.

With the development of modern technology, we now have a second solution for people who want to improve their vision at all distances, which is the use of multifocal contact lenses.

Why didn’t people with presbyopia choose them in the past?

Multifocal lenses appeared many years ago, but were only used by a small percentage of people with presbyopia. This was justified, because the lenses did not have the ability to correct astigmatism. Moreover, the multifocal technology in this small area of ​​the lens couldn’t sustain the technology of correction for all distances.

This problem, however, is no longer an issue since the creation of the most modern multifocal lenses, Omega 6. These lenses can correct even small-scale astigmatism (40% of the population has some, albeit small, degree of astigmatism). Now, thanks to the use of new technologies and the expertise of EYEART Laboratories’ opticians, everyone can have a personalized lens which can meet any of their needs, thus improving their vision and quality of life.

For more information on how Multifocal contact lenses work or about their application, make an appointment with us by calling +30 2310 282285 

Scleral contact lenses are being manufactured by oxygen-permeable materials, with a diameter slightly larger than the soft contact lenses’, so that they can be applied on the sclera (the white of the eye), which has far fewer nerve endings than the cornea.

Due to their appliance on the cornea, scleral contact lenses are deemed as more comfortable for the users.

Except for the conformity that they provide, there are many other benefits in choosing scleral contact lenses:

1. They create a stable new visual surface that completely regulates the astigmatism and the abnormal astigmatism of the anterior surface of the cornea
2. No surface of the lens touches the cornea, which should not be 'rubbed' by the lens
3. The circumference of the lens 'closes' on the sclera so that their position is stable and so that they do not shift during each use
4. The attributes mentioned above make scleral lenses the most comfortable lenses for the user
5. They are not easily affected by external conditions. No dust gets under the lens, they do not move when a lot of water comes into contact with the users’ face and they are not displaced by air

Keratoconus results in a gradual increase of astigmatism (abnormal astigmatism) and myopia until the age when its development stops. It is an optical condition that starts in most cases at the age of 15-20 years and develops until about the age of 40-45 years, without this being a standard rule, since the development can stop at an earlier age as well.

A main characteristic of patients with undiagnosed keratoconus is the frequent change of spectacles, as well as the fact that they complain of distortion and blurring of the images.

If you are familiar with these symptoms or if you have been diagnosed with keratoconus, here are some basic things to look out for:

1. You should NOT rub your eyes with pressure over the corneal area. If you feel the need to rub your eyes, rub with your fingertips only on the tip of each eyelid, where the upper and lower eyelids come into contact, away from the corneal area.

2. You should NOT be near high temperature sources, such as fire, grill, etc. If you often need to be near such high temperature sources due to your daily routine or your work, use glasses with protective filters that limit infrared radiation (heat). Your optician can advise and supply you with such glasses.