A STUDY FROM HONGKONG UNIVERSITY

What is ortho-k:
1.Is a form of vision correction.
2.It involves the modification of the corneal shape through the application of specially designed, high oxygen permeability rigid gas permeable (RGP) contact lens in order to temporarily reduce the amount of myopia and astigmatism.

Who are suitable for this therapy?

1.Individuals who can normally wear RGP lenses and
2.Who do not have more than 5 D of myopia and with less than 1.50D of astigmatism**.
3.Whose myopia are progressing rapidly.
4.Higher myopia (e.g. 6.00D) reduction may be possible for some patients. However, the success rate has not been published.
Pros:

1.In successful overnight wear, good vision can usually be maintained throughout the day after lens removal.
2.Night therapy brings convenience to those who do sports or who do not like to wear conventional contact lenses or spectacles during the day.
3.Our recent research has shown the treatment to be effective in slowing myopic progression in children.
4.On average, ortho-k can usually reduce myopia of 4.00D within two weeks. However, individual variation does exist.
5.Complications associated with conventional contact lens wear, such as dryness and irritation from dust can be avoided.
6.The treatment is reversible and can be stopped anytime. The eyes will soon resume their normal condition thereafter.
Cons:

1.Ortho-k is NOT a CURE for myopia. The treatment effect will wear off gradually after stopping lens wear.
2.Ortho-k lenses require more time to fit compared to conventional contact lenses. Aftercare consultations are more frequent to ensure effective and safe treatment.
3.Some contact lens-related problems, such as solution sensitivity, infection or corneal epithelial trauma may occur, though the risk of complication is very dependent on compliance. Improper use of these lenses can lead to corneal ulceration.
4.Treatment effect may vary and is patient dependent. Some patients may not be able to achieve the desired effect.
5.During the course of treatment, temporary spectacles may be needed.

What should I do if I am interested in the treatment?
Make an appointment with a registered optometrist who provides ortho-k services Learn more about ortho-k

what would be involved, and your responsibilities if you decide to undergo this treatment.
Have a thorough eye examination to evaluate whether you are suitable for the treatment or not.
A treatment plan should be designed for you if you are suitable.
What are the comlications involved

All myopia reduction methods have their advantages and disadvantages, and there is a risk of complication with any treatment.
Remember complications can happen anytime! Minimise the chance of these complications through good communication with your optometrist, strict compliance and regular aftercare consultations.

Final advice
For a patient who wishes to have temporary myopia reduction of myopia, ortho-k is one (but not the only) alternative. The patient is strongly advised to seek professional advice from her/his optometrist, to find out clearly what ortho-k involves for her/him, to avoid using the treatment cost to determine where s/he should have the treatment, and after commencing the treatment, to be strictly compliant. Rapport and communication between the patient and her/his optometrist is very important to
avoid unrealistic expectations
maximise safety
allow the patient to enjoy healthy lens wear
No treatment is without risk, but careful compliance by the users will reduce the chance of serious complications to a minimum.

SAFETY AND PRECAUTIONS FOR ORTHO- K LK LENS USERS

Ocular Changes During Sleep
Five major 'environment' changes when the eyes are closed.
There is no lid actions (blinking) to aid tear exchange and to eliminate debris.
There is a reduction in the oxygen supply to the cornea.
The tears become more acidic.
There is an increase in corneal temperature which can lead to increased corneal metabolic activity.
There is change in tear osmolarity due to no tear evaporation.
All these changes can affect contact lens wear.

Compliance

1.To enjoy symptom-free contact lenses, compliance is very important. Proper usage of the lens and lens care is of utmost importance. If significant bacterial contamination is introduced into the eye, an eye infection may result, therefore, strict hygiene in handling contact lenses is absolutely essential. Reports of any serious complications associated with contact lenses are rare, but usually the cause of these rare cases has been traced to some serious neglect by the patient of the instructions on hygiene, wearing schedule or maintenance procedures.
2.Optometrists/contact lens practitioners who practice Ortho-k should also ensure that they provide professional and ethical services to their patients, are properly equipped to provide Ortho-k service, and are kept up to date with their skills. It is important to communicate effectively with the patient, gain the patient's confidence, establish good rapport, and to avoid overstating the advantages and disadvantages of Ortho-k. Careful assessment and monitoring of the patient's ocular integrity is also essential to minimise complications.
Important points for patients to note

1.EACH TIME, before handling the contact lenses, wash your hands thoroughly ensuring that the sides of the fingers and the palms are cleaned. Ensure that your fingers are free of lint, cosmetics, hand lotions, hair oils, nicotine etc.

2.Contact lenses are made of plastic materials and if handled carelessly they may be scratched, distorted, chipped or split. These imperfections may be too small for naked eye observations. They can be located by your optometrist/contact lens practitioner with proper equipment during follow-up consultations. Small defects on the lens may not cause any symptoms but may allow accumulation of debris that can harbour microorganisms.

3.Do not slide or scrape a lens across a tabletop and be sure that your fingernails do not scratch the surface or dent the edge of the lens.

4.If you suspect that your lens might be damaged, have it checked by your optometrist/contact lens practitioner.
Use of contact lens solutions:

1.The tip of bottles should not come into contact with the lens, fingers or any other surface to minimise the risk of contamination.
2.The soaking solution should be changed every day, the lens container should be cleaned before use.
3.Do not change your solutions without consulting your optometrist/contact lens practitioner first, some solutions may not be compatible with the type of lenses you are using or may contain different preservatives which may cause allergy response
4.The time required for adaptation and the reactions to Ortho-k lens wear vary between individuals. It is important to be able to distinguish between "normal" adaptation problems and signs or symptoms that require advice from your optometrist/contact lens practitioner. 5.All contact lens accessories (including suckers and lens case) should be cleaned properly before use, disinfected appropriately and replaced regularly.
**Parents of children who are unable to handle their contact lenses hygienically should be prepared to do these for their children, or if not, SHOULD NOT allow their children to undergo Ortho-k treatment.

A study on Orthokeratology :Hongkong University Project

How It Controls Myopia Progression
Ortho-k can be defined as a technique where the cornea is progressively reshaped using specially made contact lenses, thereby reducing myopia. New technology has significantly accelerated the reshaping of the cornea. However, unlike LASIK, ortho-k does not lead to permanent change. Ortho-k is a treatment for reducing myopia, and it is NOT a cure. The myopia reduction effect is only temporary and the patient needs to continue to wear the lenses to maintain the effect. Our research study on myopia control with ortho-k lenses has shown that eyeball elongation in myopic children was about half the elongation observed in myopic children wearing spectacles. Effectively, this means that the progression in myopia in children undergoing ortho-k was slower by about 50% when compared to children wearing spectacles.

Some Frequently Asked Questions

Can ortho-k reduce myopia?
A1: In general, ortho-k can reduce myopia of up to about 4.50D. In some cases, reduction of up to 6.00D myopia has been known to be possible. However, it is very patient-dependent.

Can it reduce astigmatism?
A2: With most of the current lens designs, the treatment can only reduce myopia. However, new lens designs like 5 curve lenses are currently being developed for correcting astigmatism.

Can ortho-k control myopia progression?
A3: The results of recent research show that myopic progression is slower by about 50% in the children wearing overnight ortho-k lenses compared to children wearing spectacles.

How do I know if I am suitable for this treatment?
A4: You will need to consult an optometrist who will carry out a thorough eye examination to determine if you are suitable to attempt this treatment. Rapport between you and your optometrist is very important.

Physicians have said that ortho-k will hurt the eyes. Is this true?
A5: If not used properly, yes. Some discomfort (due to lens sensation) may be experienced during the adaptation period but the treatment should not hurt the eyes if properly fitted, used and managed.

My friend and I both have ortho-k treatment. Why is it that my friend can have clear vision after removing the lenses but I cannot?
A6: It depends on the amount of myopia you both have and the success of the treatment. Ortho-k is dependent on the individual. For some patients, myopia can be reduced very quickly while for others, reduction may be very slow. For example, patients with significant pre-ortho-k astigmatism, post-ortho-k vision will be poorer compared to another individual with no significant astigmatism

Why do I have ghosting/blurring of vision during the daytime?
A7: This may be due to different reasons:
the lens/lenses was/were not centering well
the retention time was not long enough
myopia was not completely reduced
presence of significant residual astigmatism
Since this problem is likely to be related to lens fitting, you need to consult your practitioner as soon as possible. Problems related to poor lens fitting may result in other ortho-k complications such as corneal staining.
Will the results of the treatment or the eye be affected if my child rubs his/her eyes during sleep?
A8: Possibly. If the rubbing dislocates or decentres the lens, vision may not be as good the next morning after lens removal .Mild rubbing may lead to superficial corneal abrasion which usually heals within a few hours after lens removal. The severity of injuries inflicted in such cases will depend on how hard your child rubs his/her eyes.

Will the results be affected if I sleep less than 6 hours a day?
A9: Inadequate sleep is not healthy for your eyes, whether you wear ortho-k lenses or not. Inadequate sleep would also cause discomfort, e.g. dry or sore eyes which may affect lens wear. Also, if you sleep less than 6 hours with your ortho-k lenses, optimal myopia reduction and retention effect may not be achieved .

Do I need to wear spectacles before achieving the reduction target?
A10: You may need to wear temporary glasses during the treatment procedures as reduction is not instantaneous but progressive. Your optometrist will be able to advise you on this.

Can I throw away all my glasses after achieving the reduction target?
A11: It is advisable to keep your glasses as there may be occasions when you may need to stop lens wear for a few days and you will then need to wear glasses. Example, if you lost a lens, you will need to stop lens wear for a few days to wait for the new lens to be delivered

CORNEA

CORNEA

The cornea has unmyelinated nerve endings sensitive to touch, temperature and chemicals; a touch of the cornea causes an involuntary reflex to close the eyelid . Because transparency is of prime importance ,the cornea does not have blood vessels and it receives nutrients via diffusion from the tear fluid at the outside and the aqueous humour at the inside and also from neurotrophins supplied by nerve fibres that innervate it. It borders with the sclera by the corneal limbus.

Size:

In humans, the cornea has a diameter of about 11.5 mm and a thickness of 0.5–0.6 mm in the center and 0.6–0.8 mm at the periphery. Transparency, avascularity, and immunologic privilege makes the cornea a very special tissue. The cornea is the only part of a human body that has no blood supply; it gets oxygen directly through the air.In humans, the refractive power of the cornea is approximately 43 Diopters.

Treatment and management

Surgical procedures
Various Refracive Eye Surgery techniques change the shape of the cornea in order to reduce the need for corrective lenses or otherwise improve the refractive state of the eye. In many of the techniques used today, reshaping of the cornea is performed by photoablation using the excimer laser.

If the corneal stroma develops visually significant opacity, irregularity, or edema, a cornea of a deceased donor can be Transpalanted. Because there are no blood vessels in the cornea, there are also few problems with rejection of the new cornea.
There are also synthetic corneas (keratoprostheses) in development. Most are merely plastic inserts, but there are also composed of biocompatible synthetic materials that encourage tissue ingrowth into the synthetic cornea, thereby promoting biointegration.

Non-surgical procedures

ORTHOKERATOLOGY is a method using specialized hard or rigid gas-permeable contct Lenses to transiently reshape the cornea in order to improve the refractive state of the eye or reduce the need for eyeglasses and contact lenses.

ALTERNATIVE TO LASIK SURGERY

IDEAL FITTING GUIDE:

1.First an initial assessment appointment to include a full Sight Test and Computerised Corneal Topographical Scan for assessment of the general condition and health of your eyes and also to discuss the likely effectivity of the procedure in your own case.
2.A pair of trial lenses are then issued for an overnight trial and your optometrist will see you the next morning. After another Sight test and scan, the change in your corneal shape and reduction in prescription is assessed. If the fit is not correct then another overnight trial may be needed.
3.Once your optometrist has established the correct fit and that he can reduce your myopia so that you will be able to achieve normal vision, a pair of OrthoK lenses will be ordered.

4. When these arrive, the fit is assessed and you will be given them to wear every night for a week. Excellent vision and comfort are normally maintained whilst wearing OrthoK Lenses.

5.You will be assessed after a week and if any modifications are needed a new pair of lenses will be ordered.
This series of OrthoK Contact Lenses, made from High Oxygen Permeable Rigid Material, gently reshape the Cornea towards less curvature and a more spherical shape. This reduces Myopia and Astigmatism whilst dramatically improving unaided eyesight.
Most of the visual changes occur rapidly in the first few days and stabilisation procedures then follow at a slower pace over the next few months. The program length varies between 3 and 6 months depending upon the degree of visual error.
6.When the maximum results are achieved, the final pair of lenses are worn to stabilise the new Corneal shape.
The final wearing time depends on many variables, but the treatment aim is to have good unaided vision all or most waking hours, with Lenses being worn overnight . Some patients will be able to wear their Lenses every other night.
WHAT ARE THE ADVANTAGES OF ORTHOK?
-Good Vision without Spectacles or Contact Lenses for Most of the day.
-It is Not a Surgical Procedure
-It is Reversible.
-It is Non-Invasive.
-It is Modifiable.
-It Does Not Hurt.
-Using well established Contact Lens Fitting Techniques mean that there are very few risks.

ALTERNATIVE TO LASIK SURGERY

Wouldn't it be great if your nearsightedness could be corrected while you sleep? It might sound far-fetched, but it's a reality for some people. It's called orthokeratology, or ortho-k, and it is available throughout the country.

Here's how it works: When you sleep, you wear special contact lenses that gently reshape the surface of your eye, so you can see clearly even after you remove the lenses. The effect is temporary — generally enough to get you through a day or so, but you must wear the special lenses each night.

HOW DOES IT WORKS

Myopia is caused by light coming into the eye in such a way that it doesn't focus properly on the retina.This problem is corrected by using eyeglasses or regular contact lenses to re-focus the light rays.
A similar result can be achieved by reshaping your cornea. LASIK is a surgical way to do this. Ortho-k contact lenses flatten your cornea without surgery, enabling light to focus properly on your retina, resulting in better vision

Is Ortho-k Comfortable?

Some people have comfort issues with daytime wear of GP contact lenses (also known as RGP or "oxygen permeable" lenses), which are used for ortho-k. With GPs, a sensation of lens awareness can result from interaction of the eyelid with the edge of the lens during blinking. (This doesn't happen with soft lenses because they are larger and remain tucked under the eyelids.) But since ortho-k lenses are worn during sleep, blinking and lens awareness are generally not a problem.

WHY YOU SHOULD HAVE ORTHO K LENSE INSTEAD OF LASIK

Ortho-k works best for people who don't want to wear glasses or contact lenses all day, every day — but don't mind wearing contact lenses at night, or occasionally during the day.
If your primary goal is to be glasses- and contacts-free during the day, then ortho-k might be a good alternative for you. However, if you want to eliminate the bother of contacts altogether, then ortho-k is not likely to satisfy you.
Ortho-k may be a good option if you suffer from dry eyes. It's been found that this condition is sometimes worsened by LASIK.
-The procedure is REVERSIBLE (Excimer is not!).
-It does not involve post-operative pain.
-It does not leave the hazy vision often experienced by patients following laser surgery.
-There is no loss of Bowman's membrane (the tough protective layer just under the Corneal surface).
-Both eyes are done together (rather than several weeks or months apart).
-Changes in prescription over time can be dealt with (unlike Excimer).
-OrthoK is significantly cheaper.

Can it also controls Myopic Progression?

In 2006 and 2007 papers presented at the British Contact Lens Association and the Global Ortho Keratology Symposium indicated the possiblility of orthokeratology slowing or stopping myopic progression. This was found to be effective in children in Hong Kong and is the subject of wider study to verify this data
Unlike LASIK, ortho-k is reversible. If you try reshaping lenses and later decide you want laser eye surgery instead, you can do that. But for a period of time before surgery (possibly several months), your surgeon would have you stop wearing your lenses so your corneas can revert to their natural shape.

ALTERNATIVE TO LASIK SURGERY

Ortho K lenses

Orthokeratology is,

The temporary reduction of myopia achieved by the programmed
application of contact lenses to reshape the cornea.
Modern orthokeratology (ortho-k) achieves this using specially
designed reverse geometry gas permeable [GP] ortho-k shaping
lenses worn during sleep.

Principle

The ortho K lens principle is based upon the fact that myopia is caused by a corneal convexity and through the lens this convexity can be subdued a little bit. It has the same effect as doing a LASIK or laser surgery. However, when the cornea returns to its normal shape, the lens has to be worn again. That period can vary from people to people. However, the average is 2-7 days and it can last longer if worn for a longer period of time

Benefits for Ortho-K LK Lens

The alternative way of myopia management, not throughout surgery
■ Higher safety than surgery (PRK), Low critical side effect
■ Can be reversible after 3~4 weeks, discontinuing lens wear
■ Effective to reduce myopia at every age, especially juvenile
■ Can be controlled myopia progression as well as myopia reduction
■ Easy to reduce myopia by overnight wear of lenses
■ Not necessary to wear lenses at day time
Limitations

There are no known side effects until now. Except the discomfort when wearing a normal RGP lens. Because the cornea returns to its position, please take off the lens and consult an ophthalmologist when any problems arise. If you follow their instructions, it will recover 100% in days. It is also good because there are no limits to it. Whether you are a man or woman, there is an effect in stopping myopia from getting worse. Therefore it is very comfortable for growing children, people incapable of surgery, athletes, pilots, stuntmen, artists, captains of air flights who can't wear lens all the time

Target Group

No limits to the use. However, people with severe dryness in the eye can be applied, - with high myopia going beyond 5 D - with higher than 2 D astigmatism, consult an ophthalmologist first.

Anatomy of Eye

A guide to Anatomy of the human eye

The ability to see is dependent on the actions of several structures in and around the eyeball. The graphic below lists many of the essential components of the eye's optical system.

When you look at an object, light rays are reflected from the object to the cornea, which is where the miracle begins. The light rays are bent, refracted and focused by the cornea, lens, and vitreous. The lens' job is to make sure the rays come to a sharp focus on the retina. The resulting image on the retina is upside-down. Here at the retina, the light rays are converted to electrical impulses which are then transmitted through the optic nerve, to the brain, where the image is translated and perceived in an upright position!

Think of the eye as a camera. A camera needs a lens and a film to produce an image. In the same way, the eyeball needs a lens (cornea, crystalline lens, vitreous) to refract, or focus the light and a film (retina) on which to focus the rays. If any one or more of these components is not functioning correctly, the result is a poor picture. The retina represents the film in our camera. It captures the image and sends it to the brain to be developed. The macula is the highly sensitive area of the retina. The macula is responsible for our critical focusing vision. It is the part of the retina most used. We use our macula to read or to stare intently at an object.

CONTACT US :

Launching Something new in Ophthalmology (ORTHO K LENSES ) by end of the May

Mr. Pankaj
Managing Director

BE(Civil Engg)
+91-09899268672

Ms . M.Prriyadarshini (MSc.,MBA)

Executive Director

+91-09810749470

email:- prkamyavisions@gmail.com

Mr.Ravi Singh

Technical Support Manager

+91-9911904708

email:-raviprkamya@gmail.com
Visit us: http://www.prkamyavisions.co.cc/

MISSION OF OUR COMPANY

The mission of Prkamya Visions is to market and in later stage manufacture and export high-tech Equipments in foreign Countries. The equipments under Prkamya should itself define one of the best technology Equipments which fill a current need in medical procedure by improving upon an existing technology or instruments, or by launching device to serve a need that is clearly defined and acknowledged by medical professionals. Each product shall be priced to appeal to a managed-care market that stresses lowest cost of total treatment parameters. Every Year under the aegis of Prkamya, Minimum two Eye Camp will be launched in remote areas to give vision to poor people in India.

M.Prriyadarshini,

Prkamya Visions
visit us : http://www.prkamyavisions.co.cc/


For more details you can also visit us :www.prkamyavisions.co.cc

PRKAMYA VISIONS

WELCOME TO PRKAMYA VISIONS

For us "your vision is our mission "

Prkamya Visions is committed to market Best Quality and High-tech "Optical, ENT and Ophthalmic Equipments and Instruments" at competitive price, bearing in mind the stated & implied needs of the CUSTOMER. Its endeavor to introduce new ophthalmic technologies, into the medical community in India. Products ranging from simple optical and refraction devices to advanced laser systems were sourced from leading international and national ophthalmic instrument companies around the world.Company has three divisions:

Capital Ophthalmic Equipment Wing
In this wing,we cater the needs of Big Eye Hospitals/Eye clinic and Insititutions by providing them best quality Imported equipments at affordable price.

OPTO PRODUCTS :-Sub Distributor (Delhi,NCR ,Bihar&Jharkhand) of Opto-global System,Australia ,One of the leading Company in Ophthalmology.These are,
1. Opto Angiocam (Fundus camera)

2.Opto Advant Yag laser(1064nm)

3.Smart chart (wall mount/table mount)

4. Surgical microscope(Both Eye and ENT )

5.Green laser,IMP & TTT laser

6. Automated Perimeter(blue & yellow and white &white)

SONOMED,USA

Sonomed is the worldwide leader in ophthalmic ultrasound, with 30 years of experience helping ophthalmic professionals use ultrasound to measure, diagnose, and plan. The major products offered by the Company are:

1.Sonomed A-scan with Immerssion Shell

2.Sonomed Pachymeter

3.Sonomed B-Scan and Vumax UBM

OCULAR LENSES

DISPOSABLE WING
In this wing, we are into marketing of Intraocular Lenses,Surgical & ophthalmic drapes and all type of Consummables in the field of Ophthalmology directly from the factory at affordable prices with no compromise of quality in all over India.
1.Aspharic Intraocular Lens(USA)
2.Surgical and Ophthalmic Drapes

Indian Opthalmic Equipments and Instruments

In this division,we are into marketing Indian Ophthalmic Equipments and Instruments Eye clinic and ophthalmic Hospitals.The major products are:

1 Indian Slit lamps(Export quality)

2 Retinoscope(Heine/Welch-allyn)

3.Ophthalmoscope(Heine/Welch-allyn)

4.Keratometer

5.Synaptophor

6.Indian Instruments

Ms . M.Prriyadarshini(MSc.,MBA)

Executive Director

A.S Plaza , Shop No 101, Opp I-9 Sector -16 Rohini New delhi-110085, India

Tel: 91-11-32598139,9810749470,9350763994

mailto: prkamyavisions@gmail.com

visit us: http://www.prkamyavisions.co.cc/