Custom contact lenses might be for you if you can’t use regular contact lenses due to the fact that of issues such as an irregularly shaped eye or too much astigmatism.
You also may consider custom contact lenses if regular contacts are unpleasant or cause vision problems.
Customized contacts are available both in rigid gas permeable (RGP or GP) and soft lens materials, and may be able to supply sharper vision and higher using convenience than regular GP or soft lenses.
Gas Permeable Custom Contacts
The majority of eye care specialists concur that gas permeable contact lenses usually supply sharper vision than soft contacts. This particularly is true for people with specific types of astigmatism.
However some people find gas permeable lenses hard to get accustomed to. GP lenses are developed to produce a minor space in between the edge of the lens and the eye’s surface. This “edge lift” enables tears to flow behind the lens during and after blinks to supply more oxygen for eye health.
Sadly, the interaction in between the edge of gas permeable lenses and the eyelid and the motion of GP lenses during blinks can make these lenses unpleasant for some users.
Also, for individuals with uncommonly shaped corneas, it might be difficult to fit the eye effectively with traditional GP lenses so the lenses remain effectively fixated the eye. This increases the risk of discomfort and variable vision.
To overcome these restrictions and make it possible for more people to enjoy clear, comfy vision with GP lenses, contact lens producers are now using sophisticated innovation to develop personalized gas permeable lens alternatives.
The fitting and lens manufacturing procedure for gas permeable custom contact lenses varies from standard GP lenses in two ways: how your eye is determined and how the lenses are designed.
Eye Measurements, Lens Designs For Conventional GP Lenses
Comprehending how standard GP lenses are fitted as part of a contact lens eye examination will help you understand the complexities of custom contact lenses.
The majority of eye care practitioners determine the curvature of the front surface of the cornea with an instrument called a keratometer.
The keratometer uses light reflections from the cornea to determine the steepest and flattest meridians of the eye. To envision how this works, think of that the front of the eye is like the face of a clock. A line connecting the 3 and the 9 is one meridian; a line connecting the 12 and 6 is another meridian, and so on.
The curvature of a traditional GP contact lens is based on 3 keratometry measurements: the curve of the steepest meridian of the cornea, the curve of the flattest meridian and the orientation of the flattest meridian– in other words, whether the flattest meridian is horizontal, vertical or someplace between.
Based on these measurements, the eye care professional or lens maker chooses the curves to apply to the back surface area of the GP lens for the best possible fit. With a conventional GP lens, the back surface area normally has one curve for the central part of the lens (called the base curve) and two or more flatter curves in the periphery of the lens.
These flatter curves help the lens align better to the surface area of the cornea, which typically ends up being flatter in the periphery. The peripheral curves likewise provide the appropriate quantity of edge lift so tears can flow behind the surface area of the lens during and after blinks.
Eye Measurements, Lens Designs For GP Custom Lenses
Compared to conventional techniques, the eye measurements and lens designs for custom gas permeable lenses are far more complicated.
Rather of acquiring simply three measurements of the cornea from a keratometer, the eye care specialist who fits GP custom contact lenses uses an instrument called a corneal topographer to get curvature information from several thousand reference points on the eye.
These information points form an in-depth map of the curvature of the eye, which the eye care professional and lens maker then use to design a multi-curved lens surface that conforms much more closely to the surface area of the cornea.
This tailored design and fitting process produces a more comfortable fit – especially on irregularly shaped corneas and corneas with high degrees of astigmatism.
In addition to being produced with advanced lens fabrication equipment capable of producing surfaces with smoother point-to-point curvature modifications, custom GP lenses typically are made with more recent gas permeable lens products that enable more oxygen to pass through the lens to the eye.
Since these newer materials enable more oxygen to reach the eye directly through the lens, eye care practitioners and contact lens producers do not need to depend on tears pumping beneath the lens to maintain eye health. Therefore, the edge lift of tailored lenses can be securely reduced and the curvature of the edge of the lenses can conform much better to the peripheral cornea for a more comfy fit.
Who Can Benefit From GP Custom Contact Lenses?
Nearly anybody who is disappointed with their vision with traditional soft contacts or who has tried standard GP lenses and found them uncomfortable might be a good prospect for GP custom contact lenses.
And due to the fact that custom GP lenses can be fabricated to fit uncommon corneal surface areas, they frequently are an excellent solution for individuals with keratoconus or uncommon corneal curvature– from natural causes, an eye injury or from a not successful LASIK procedure or other corneal refractive surgery.
Likewise, multifocal custom gas permeable contact lenses are showing fantastic pledge for the correction of presbyopia. And some eye care specialists report that custom GP lenses are more effective than traditional GP lenses for orthokeratology– a non-surgical treatment for myopia and astigmatism.
Soft Custom Contact Lenses
Though the majority of custom contact lenses currently are made from rigid gas permeable lens materials, custom lenses likewise are offered in soft lens materials, including brand-new extremely oxygen-permeable silicone hydrogel polymers.
A number of contact lens makers use unique style soft contacts for hard-to-fit eyes. These styles feature smaller and bigger sizes and a larger variety of curvatures and powers than traditional soft lenses for a more customized fit. A few of these producers likewise provide custom toric contact lenses that correct greater amounts of astigmatism than conventional soft toric lenses.
The majority of traditional toric soft lenses can fix only up to 2.50 diopters (D) of astigmatism and are readily available in astigmatism-correcting power increments of 0.50 or 0.75 D. Custom toric soft lenses can remedy much greater amounts of astigmatism and can be bought in finer increments (0.25 D) for a more precise correction and potentially sharper vision.
Other types of custom soft contact lenses consist of:
- Multifocal toric contact lenses that can remedy practically any mix of refractive errors and presbyopia.
- Multifocal lenses specially designed for myopia control in children.
- Custom lenses made from innovative silicone hydrogel products that are made with a lathe-cut process similar to those used to produce GP lenses for an almost endless degree of personalization.
A number of contact lens makers use custom soft lenses for a wide range of applications. During your contact lens examination, your eye doctor will figure out whether you need custom lenses and describe which designs are best fit to your needs.
As with custom rigid GP lenses, fitting soft and silicone hydrogel custom contact lenses is more complicated than a conventional contact lens fitting and often involves making use of special equipment to measure corneal topography and higher-order aberrations to help in the design and fitting of the lenses.
Custom Contact Lens Care
Taking care of custom contact lenses is no various than caring for standard GP and soft lenses, and the same contact lens options can be used on custom lenses.
Custom contacts typically are created to be worn for longer durations between lens replacements than traditional contact lenses. This makes proper everyday lens care even more crucial to keep the lenses clean and comfy.
Make certain to speak with your optometrist regarding the correct using time, replacement schedule and care products to keep your custom contacts comfy and lower the risk of contact lens-related complications.
Cost Of Custom Contact Lenses
Though custom contacts cost more than traditional soft or GP lenses, they have the potential of supplying visibly sharper vision than standard prescription contacts or glasses. Custom contact lenses likewise are a good option to LASIK and other types of vision correction surgery, without any fret about LASIK risks or prospective surgical complications.
Because of the additional competence, time and innovative equipment required to fit custom contact lenses, these made-to-order lenses typically cost considerably more than regular contact lenses. Your eye care expert can encourage you of the cost of the particular type of custom lenses best fit for your requirements.
To see if you’re a good candidate for custom contact lenses, contact an optometrist near you for a detailed eye exam and contact lens assessment.
