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QUESTION:
Is astigmatism in cyclopegia the same as astigmatism in non-cyclopegia or not?

This is a technical question, and the patient shows to know the methods used by ophthalmologists to highlight refractive errors.

ANSWER:
The patient’s doubt is correct. The astigmatism highlighted in cyclopegia is not truthful since cyclopegia causes an unnatural stretching of the crystalline lens as a secondary effect, hence the evaluation of astigmatism is slightly distorted.
The doctor is usually aware of this problem, so he takes the results with a pinch of salt and with the proper considerations; in any case, another evaluation out from the presence of the cycolopegic effect would be useful and fair.

For World Vision Day the CDV - Committee of Sight Defense - launched an alarm in Milan last october regarding visual problems for all those working at a computer. The CDV, assisted by its consultant, Dr Francesco Loperfido, responsible for the service of General Ophthalmology in the Operating Unit of Ophthalmology and Vision Sciences at the San Raffaele Hospital in Milan, underlined that since everything is computerized, we spend hours in front of the video, and this causes various problems, from posture to sight.
According to a recent survey made by the VCA (Vision Council of America), 90% of those working at the computer have eye problems relating to its often incorrect use.
There are two kinds of ways of working at a computer: passive (when the worker puts in the data from a paper support) or active (the worker looks at the screen without reading paper support, and therefore move the eyes only from the keyboard to the screen). The correct posture, lights, screen and way of sitting: if these variables are not adjusted correctly, visual problems may arise.
An under-corrected myopic person modifies his or her posture by leaning forward and putting too much strain on the neck; the hypermetrope has the opposite problem because after a while the characters are seen double and he/she tends to move away from the screen, a problem which is accentuated with presbyopia. Lastly, astigmatic persons tend to have a sideways posture to compensate for high astigmatism. All these forms of compensation may cause a series of disorders which take the name of accommodating astenopia.
Moreover, screens set up reflection on the outer and inner surfaces of lenses, which overlap visual images on the retina and crate halos which tend to tire the eye. It is therefore a good defense to use lenses with AR filters. For those with several visual defects, the solution is to use progressive lenses. Some colored lenses may be useful to reduce background light and improve contrast. The decision to use contact lenses must also be carefully weighed up. In front of the screen, ocular blinking becomes less frequent, the lachrymal film is reduced and the eye is visibly dryer. The position of the chair, desk, screen and light is also very important.
The new flat monitors favor a greater distance between the eye and the video and seem to also reduce electrostatic fields, one of the causes of the “dry eye” sensation.
Reflection on screens and other equipment must be avoided, light must be present but moderate and the contrast between the screen and environment appropriate.

Vedere International 2009