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The general rule for the correction of hypermetropia is to use the most powerful lenses that do not blur the eyesight. These lenses measure and correct the manifest hypermetropia. A more powerful correction is prescribed only in special cases.
In correcting the hypermetropia, besides that it ensures that the radiations from infinite are focused on the retina, should also ensure that the level of accomodation coincides with the convergence; therefore when correcting the hypermetropia, when there is a accomodation discompensation, it is necessary to balance the eye muscles.

When the eysight is normal and there are no discompensations, no symptoms ofastenopia, it is not necessary to correct the eyesight.

If instead there are symptoms of astenopia, but the eyesight is 10/10 and does not improve with additional lenses, only reading glasses are prescribed. When the astenopia is reduced within 10 days, the correction should be worn constantly.

Normally it is not difficult to decide whether the correction should be worn all day, but in case of doubt, it is important to measure the amplitude of accomodation with the convergence at infinite.

When the eyesight is less than 10/10, the correction must be worn all day and even if the eyesight does not improve initially, one has to wait that this occurs with the complete correction. The correction should be worn all day also in the case of exphoria or exotropia.
From Optometria e Oftalmologia by Prof. Sergio Villani (Volume One).

Various types of graduated prescription lenses

When talking about the computerized video-keratography we considered the degree of the cornea’s curvature as a known fact, even if susceptible to treatment. It could be interesting though to look at the past and talk about the big names of’ Ophtalmology and Fysiological Optics in nearly 4 centuries

In 1629, Father Scheiner studied the cornea, considering it as if it were a convex mirror. The debree of average curvature, measured on 10 individuals, was 7.87 mm. Similar attempts were made in the following years, for example by Ramsden in 1796 and by Young, in 1801.

This last one researched the relation between the curvature and astigmantism. In this context, Young was able to show the image projected on the inner surface of the cornea.

Source Luce e Immagini by Prof. Sergio Villaniand Prof. Luigi Santalucia.

The test is performed on both eyes with a skiascopy stick, made of two sticks containing spheric lenses ranging from +.50 to +4.00 dyopters at .50 intervals.

The double row of lenses is passed in front of the eyes of the observer. If our observer has been corrected of his long-sighted ametropies, he is asked to fix on a point on the skiascopy at 33 cm. With the appropriate stick spheric lenses are added in front of both eyes, starting with +.50 till a neutral point (inferior) is reached which is usually at +.50 D. This is continued till the movement becomes discordant (superior neutral point). If we have added +2.50 D we calculate the difference (in this case +2.50 - +0.50 = +2.00 D) which gives the level of relative negative accomodation, that is the measure of how much accomodation can be released maintaining the convergence for a specific distance.

Because the observer has been corrected for farsightedness, at 33 cm he can accomodate up to 3.00 D. For this reason his relative negative accomodation should not be higher. If it is, we are in the presence of of a latent hypermetropie for far away objects that minifests itself close by.

With this method, within certain limits and ability of the operator , we can avoid the cycloplegy.

From Optometria e Oftalmologia by Prof. Sergio Villani (Volume One)

Related article: Measurement of Hypermetropia with the recession method

Various types of graduated prescription lenses

Which is the product of your brand dedicated to the sports?

Nike
Sun: the Impel model, for running, with temples in ultra-light magnesium of 18g is able to satisfy the requirements of professional athletes and the sunday runners; View: model 7030, completely in plastic without metallic parts, ideal for the sports but also “cool”.

Nannini
Modular 1 Discovery, more a “tool”, like skis and tennes rackets, than “simple” glasses.

Oakley
Radar and Flak Jacket also for the winter: the interchangeable lenses and the new technology that renders them oily and hydrorepellent (invulnerable to athmospheric conditions, creams, fingers, i.e., clean and functional) turn it into a versatile, winning and innovative product.

Rudy Project
The Zylon model offers protection and comfort, thanks to the special lateral shields, conceived to protect the eyes from lateral reflections, wind and water drops, and to the new exclusive ImpactX Photocromatic Clear lenses. The frame is in Grilamid, the terminals can be adjusted 360° and the bridge is ergonomic. The lenses are interchangeable, chosen from 15 different types of filter. Through the patented easy-in easy-out system, Zyon may be equiped with optical clip-ons, to be clicked-on behind the sun lenses, in order to practice sport at the maximum level also by whom wears graduated lenses.

Tag Heuer
The 27° Air Tag Heuer, with various lenses that are interchangeable in a very simple way on a bar with hinges without screws designed by Ross Lovegrove, designer of the Audi TT, winner of the Silmo d’Oro. The various lenses from which to chose render the frame apt for many sports, from skiing to sailing, from golf to driving.

Zerorh+
The Morphologic 3D mask, tridimensional and created with innovative technology, with a futuristic shape and aerodynamic lenses. The totally wrap-around lenses, the lightness of the frame, the sturdyness and the possibility to mount eye lenses make the Morphologic a high precision sport tool.

Source b2eyesmagazine, 15 September 2007

Articolo correlato: Sport and Glasses (1/2)

Occhiali Sportivi su Giarre.com

The best method for making the latent hypermetropia manifest is through the recession method. It consists principally is placing two positive lenses of 1.00/1.50D in front of each eye which have already in front of them the correction for farsightedness; the patient is asked to observe the optotype from .5 meter distance. Then the optotype is pulled further away till the picture becomes hazy; slowly, always starting from a 50cm distance and pulling the optotype away from the patient up to 5 meters one can arrive at a relaxation of the accomodation.

The above described method is used involuntarily by many presbytes who, corrected with reading glasses, often raise their eyes to look at distant objects not remembering to lower or to remove their glasses.

From Optometria e Oftalmologia by Prof. Sergio Villani (Volume One)

Related article: Correction of Hypermetropia with binocular vision

Which new sport disciplines are at the attention of the end-consumer and in the acquisition of technical frames?

Nike
Running and golf are the two categories of business on which the brand management efforts are concentrated.

Oakley
From the point of view of image, the America’s Cup has played an important role this year, like the Motor GP it attracts a growing public. For the effective use of sportive frames, however, the “classic” sports are more important: bycicle racing, ski and running. A new way of doing sport, often accompanied by an MP3 player; in this sense the model “Thump” is highly successful because it incorporates in the temples a high-quality wireless audio system.
Tag Heuer e Vuarnet
Not all new disciplines are being watched, because the brand has a consolidated sportive profile. Tag Heuer presents a new frame for multi-function sports in order to be closer to the requirements on the base of colours. Furthermore, the lenses, made of polarizing tempered chrystals Vuarnet to the Tag Heuer hydrorepellant polarizing photocromatic lenses, satisfy the most diverse requirements.

Zerorh+
In Italt, golf, because of technical necessity and buying power, represent a potential growth market. Also sailing offers growth potential through the development of a product with better performance in terms of polarizing photochromatic lenses (Stylus lenses, see safe polarizing photochromatic rh 616); or new potential uses as a protection not from the sun but from impacts: indoor sports like basketball, could represent the opportunity for products with anti-impact technology such as the See Safe in NXT (metheo nxt rh 631).

Rudy Project
Triathlon, golf, but above all sailing, between passion and business has been sponsoring the spanish Desafio team of Valencia and now it has a true team at the Match Race world cup, the training ground for the America’s Cup.

Source: b2eyesmagazine of 15 september 2007.

After each eye has been corrected separately, we often find that the eyesight has remained the same even when adding two slightly positive lenses on each eye. The quantity of added power without worsening the eyesight is equal to that of the accomodation that is being relaxed. This can be possible only for +.25D but usually one can achive higher powers: up to +1.00D and even more.
As a rule, the younger the subject, the higher the relaxed quantity and vice-versa.
If, in the case of exophoria, the quantity of manifest hypermetropia becomes an essential condition, it is recommended to take the measurement and to prescribe the quantity found with binocular vision.
Often in subjects that are supposed to be emmetropic, taking the measurements, a slight hypermetropia is encountered.
If exophoria is present, it can happen that we find a certain amount of hypermetropia in monocular vision while it is less with binocular vision.
This result, which shows the opposite of what we said before, is justified by the fact that with monocular vision convergence is not stimulated, the hypermetropia shows itself more completely when there is no convergence effort to bring the visual axes in parallel. If also the accomodation is stimulated, the correction found with monocular vision is too strong.
The correction of latent hypermetropia, measured binocularly, can show various values for a small part of the hypermetropia which is some moments may overcorrect resulting in a fuzzy eyesight.

From Optometria e Oftalmologia by Prof. Sergio Villani (Volume One).

Related articles: Measuring hypermetropia by defocusing

For a triangular face
The objective is to widen your brow and to soften your jaw line and make it less prominent.

• Choose a frame style that angles up and outward at the top corners.
  
• For women, cat’s-eye shapes are flattering.
  
• For men, square frames are attractive.
  
• Frames with rimless bottoms are also good for both men and women.
  
• Frames with temples and bridge located near the top of the frame are best.
  

• Choose frame styles that angle outward at the bottom.
  
• Aviator and “bow tie” shapes are a good choice.
  
• Rectangular styles are also good.
  
• Frames with temples and bridge located near the middle of the frame help balance facial features.
  

• The goal is to make your face appear wider and shorter.
  
• Choose round styles or geometric shapes with large vertical dimensions.
  
• Decorative temples or temples with contrasting colors widen your face.
  
• Frames with temples and bridge located near the middle of the frame are best.
  

That’s all Folks!

Preceding article: Chosing the right frame for you (4/5)

We have said before that measuring hypermetropia, continuing to increase the power of the lenses, one will find one that worsens the eyesight and thus to use one before the eyesight became fuzzy.
The defocusing system works like this: if the maximum positive power which enables to read 10/10 is a +2.00D and a +3.00D lens worsens the eyesight, one goes backwards trying a +2.75D lens, a +2.50D lens, etc. With a latent hypermetropia one can certainly achieve a 10/10 eyesight with the initial lens power > +2.00D.
Important in this operation is that the more powerful lens is not removed before the weaker lens is put in front of the eye.
Also with this technique, to achieve the maximum positive correction possible, it is desirable to make the measurements on both eyes. Even if there are doubts on the efficiency of this system to obtain the maximum measure of manifest hypermetropia, it is a better system than to increase the power of the lenses gradually.

From Optometria e Oftalmologia by Prof. Sergio Villani (Volume One).

Related articlesi: Various types of prescription graduated lenses