Today, thanks to the contact lenses, we can treat many vision problems. Scientific researches about contact lenses realized many progresses in the last few years: materials, geometries, way to wear them, kind of contact lenses and technology used to make them, have had many fruitful improvements. People who are used to wear contact lenses are periodically checked: the purpose is to give them the better contact lens we can, talking about comfort, vision and safety. Contact lenses are recommended for many persons: there are many vision problems that can be better treated with contact lenses instead of ophthalmic ones. At the Santona Optic Centre we do applications of contact lenses for subjects of all ages, taking care of maintenance procedures for your safety: children, kids, teenagers and adults can have another option to glasses in different circumstances (school, sport, work and free time). It is possible to set an appointment to try or check your own contact lenses even on our web site.
Application of contact lenses
Contact lenses represent a good instrument to correct refractive errors, especially the most commons (myopia, hyperopia, astigmatism and presbyopia). There are many indications and some contraindications related to the use of contact lenses. The three criteria you need to follow in order to have a proper application are:
Vision criteria: the contact lens needs to guarantee a good vision performance and the best vision acuity the subject could achieve.
Physiologic criteria: contact lens needs to respect the right corneal conjunctive metabolism, without damaging the eye system balance.
Comfort criteria: the contact lens needs to be comforting, without that annoying sensation of a foreign body in your eye.
ADVANTAGES AND DISADVANTAGES OF THE CONTACT LENSES USE
The optic correction with contact lenses requires attention and punctuality. It is important to have a proper maintenance and a good personal hygiene (especially your hands hygiene), in order to avoid microbial or chemical contaminations of lenses or eyes. For further information, it is possible to check our web site at the voice “maintenance of contact lenses” in the Contactology section. The use of contact lenses also requires frequent eye exams, at least each six months, in order to check the state of the contact lenses and the condition of the anterior segment of the eye. That’s why, if you want to use contact lenses, you need to be motivated and aware; the only esthetic reason (not to wear glasses for a better social image) is important, but it is not enough. Contact lenses represent a valid alternative to glasses, especially for optical reasons. Contact lenses, indeed, do improve the vision performance in case of a high ametropia, anisometropia (an important difference between the two eyes diopter) and in case of irregular corneal astigmatism (given by keratoconus, corneal scarring or surgeries). Sometimes contact lenses are used for therapeutic purposes, to facilitate the recovery of ocular pathologies or to reduce their symptoms, or even to improve vision functions in case of amblyopia or nystagmus. Contact lenses are also used during the night, in order to restore the clear vision and not to need optic correction during the day (orthokeratology).
CONTACT LENSES TYPOLOGIES
There are many contact lenses categories. They are generally classified looking at the material (rigid, soft or hybrid) or the frequency of substitution (single-use, with scheduled replacement, conventional). Rigid contact lenses are made of gas-permeable materials and used for specific applications of advanced contactology (keratoconus, post-surgery or orthokeratolgy). Soft contact lenses can be made of hydrogel materials, hydrogel-silicon or biopolymers; the choice of the polymer and geometry of the more appropriate contact lenses is made taking account of the vision problem and the subject’s lacrimal characteristics, personal needs and way of use. Contact lenses can be daily replaced, with frequent scheduled replace (weekly, bimonthly or monthly) or with extended replace (biannual or annual). Santona Optic Centre offers a large variety of contact lenses; we give you the possibility to try many typologies, materials and geometries, and to evaluate the advantages after a few days. To discover the whole collection of the Santona Optic Centre you should visit our website at the voice Contact Lenses, section Products.
Contact Lenses Maintenance
The single use contact lenses, with daily replace, must be eliminated after the use. Others typologies of contact lenses require a proper maintenance, in order to avoid infections and complicacies. Two main steps compose maintenance procedure: cleaning and disinfection. To clean contact lenses is necessary a cleaner with surface-active substances, which can remove lipid deposits, detritus and microbial biofilm. Its action must be completed by a mechanical scrubbing, a rinsing with salty solution and a following use (every week) of enzymes for proteins removal. Disinfection of contact lenses is made up with preserved chemical solutions or antioxidant systems. Today the most common solutions for contact lenses maintenance are the multipurpose solutions, so called because they can provide at the same time:
RULES FOR AN APPROPRIATE MAINTENANCE OF CONTACT LENSES
Rules to follow for a good maintenance of contact lenses are:
Manipulating contact lenses, for both application and removal, hands need to be cleaned with soap, rinsed and dried.
Use maintenance solutions given by your optic-optometrist, which are chosen since adapt to the contact lens material and to the subject’s lacrimal characteristics.
Respect the date of expiry of maintenance solutions, not to use them in case of bottles opened from more than a month;
During the application of contact lenses, rinse and wet them (if they fall or get dry) only with the saline solution and not with water;
Before putting contact lenses in the container, use the tooth brush or a cotton stick with contact lenses detergent; rinse it with hot water and then leave it drying in the air, protected by the dust;
Change the container each two months.
Multifocal and toric contact lenses
Contact lenses also correct astigmatism and presbyopia; we must distinguish toric contact lenses and multifocal contact lenses.
In both cases, the choice of the most appropriate contact lens requires a deeper analysis then for spherical contact lenses application. There are, indeed, many factors to consider in order to achieve an optimal application. Santona Optic Centre takes care of it: we assist the subject by giving him many examples, so that he can check comfort and vision during his daily activities. Thanks to this step, we can find the ideal contact lens and we can order the definitive typology. The subject his later followed and periodically checked, to have the possibility to change the contact lenses he is using with new generation ones.
CONTACT LENSES AND ASTIGMATISM
Contact lenses for astigmatism correction are defined torics or astigmatics. There are many typologies, different in materials (rigid and gas-permeable, soft in hydrogel or hydrogel silicon or biopolymers), geometries and stabilization systems (prismatic, dynamic), frequency of replacement (from daily to annual). The application of toric contact lenses requires an exam with a refractive analyze, the study of the corneal curvature through topography or keratometry.
CONTACT LENSES AND PRESBYOPIA
There are many ways to offset presbyopia, both with ophthalmic or contact lenses. In the second case, we can adopt multifocal contact lenses, specifically made to correct any vision disease due to the presbyopia. These contact lenses can be used by people who have problem in the proximal vision because of the presbyopia, which causes a reduction of the accommodative width and so of the capacity to closely bring into focus. We have two families of multifocal contact lenses: with simultaneous vision, which gives more dioptric strength in the diametric pupil corresponding zone. Simultaneous vision contact lenses base their efficacy on the interaction between retina and cerebral cortex. An active selection process of the stirrings controls the flow of vision information, which everyone receives. So all images coming from different distances are selected by the cerebral cortex. They overlap in the brain and it is the brain itself, that select the most important ones, that decides on what to focus. The application of multifocal contact lenses is for people wearing contact lenses for years (correcting ametropia like myopia, hyperopia and astigmatism) who, for matters of age, are starting to have difficulties in the proximal vision. For those people, it is natural to switch from a contact lens for distant vision to a multifocal lens, adding the proximal distance vision. The application of multifocal contact lenses can be proposed to people who have never worn any optic correction and is starting to have difficulties with the proximal distance. In this case, the multifocal contact lens represents a valid choice for people who refuse, for comfort or aesthetic reasons, the idea of wearing glasses.
Contact lenses for keratoconus
As well as for the correction of common ametropia, contact lenses can be applied, with many vantages, in case of keratoconus or cornea submitted to a surgical procedure. The keratoconus is a not inflammatory thinning of the central portion of the cornea, which become pointy (ectasia) and more curve. It causes a high level of irregular myopic astigmatism, due to the corneal distortion, and because of the different position the apex of the cone assumes in comparison to the central part of the cornea, where the vision axis passes. The keratoconus starts without symptoms and can be recognized only with an eye exam that includes the corneal topography. While it progresses, it gives a reduction of quality vision, often associated to a monocular diplopia and/or photophobia. Every treatment, in case of keratokonus, has as main purpose the improvement of vision acuity, which results damaged by the irregularity of the corneal curve and the apical opacities in the most advanced cases. In the keratoconus, the application of rigid and gas-permeable contact lenses, guarantees the possibility to have a better vision acuity then with ophthalmic lenses.
Children and contact lenses
In the last few years, a bigger opening to the possibility of contact lenses for children has spread. This has been enhanced by a deeper clinical and scientific knowledge about corneal physiology and lacrimal film of children, the improvement of contact lenses (materials and geometry) and applying techniques. In pediatric age, the application of contact lenses is indicated for optic-functional purposes or esthetic reasons. The child’s vision system is under development, so it is in a delicate and important phase; that is why the application of contact lenses, when requested for refractive reasons (high ametropia or anisometropia) or pathologic reasons (anidridia, albinism, surgeries), needs a cooperation between optic-optometrist and eye doctor. Major advantages of contact lenses application during the development age arrive in case of anisometropia (high difference between the two eyes dioptric); contact lenses can avoid negative effects (aniseiconia and anisophoria) given by glasses correction.
Even in case of high ametropia, contact lenses are perfect since they reduce aberrations and avoid variations in the image’s size, which is given by strong ophthalmic lenses. The kid, by growing up, becomes more self-confident, and the contact lenses application has often a positive effect on his psychological condition with an improvement of his self-esteem and social interactions.
The application of contact lenses in the kid is strictly recommended if he does sport: contact lenses prevent eyes or facial wounds given by the impact with glasses in case of a soccer ball, fall or unexpected collisions. The kid, if sufficiently motivated, often feels responsible and, with contact lenses, learns how to handle the personal hygiene, he pays attention to procedures for conservation and maintenance of contact lenses, and he becomes punctual in substitutions.
Santona Optic Centre has acquired, year by year, a high professionalism doing vision exams to children and finding solutions for them, especially with contact lenses. For further information, you can visit the site at the section Children and Vision.