Perifocal-Ms - Perifocal spectacle lenses - official website

Perifocal spectacle lenses - safe multi-factorial influence on myopia
Perifocal spectacle lenses - safe multi-factorial influence on myopia
Perifocal
Go to content

Perifocal-Ms

Technical description
Perifocal-Ms is a spectacle lens for restraining the development/progression of myopia. The additional index (s) indicates an earlier start of addition and faster saturation with higher values horizontally relative to the optical center of the lens, in contrast to the Perifocal-M. These properties of the lens allow you to create myopic defocus on the retina earlier, relative to the fovea, faster to achieve stronger (by 0.5 D.) defocus on the periphery horizontally in contrast to the perifocal-m lens, which increases the effectiveness of the therapeutic effect on the progression of myopia.
The lens has an asymmetric progression on both sides from the optical center horizontally. The value of nasal (towards the nose) addition is 2.5 D with the beginning of the progression in 4.5 mm from the optical center and the saturation of the progression in 24mm from the optical center horizontally. The value of temporal (in the direction of the temple) addition is 3.0D with the beginning of the progression in 3 mm from the optical center and the saturation of the progression in 24 mm from the optical center horizontally. On the front surface of the lenses there is a visible yellow marking with the designation of its optical center and horizontal (the presented marking is also applied to The perifocal-Ps lenses).
Design
Progression beggining
Central aperture
Progression saturation from optical center
Progression value (D)


Nasal (N)
Temporal (T)
Central
Nasal (N)
Temporal (T)
Nasal (N)
Temporal (T)
Perifocal-M
6 mm
4 mm
10 mm
25 mm
25 mm
2,0
2,5
Perifocal-Ms
4,5 mm
3 mm
7,5 mm
24 mm
24 mm
2,5
3,0
Thus, the optical properties of the Perifocal-Ms lens in comparison with Perifocal-M have a number of important advantages:
· an earlier start of addition relative to the optical center allows for the effect of myopic defocus on most of the retina near the fovea. This is important for enhancing the therapeutic effect, because according to mfERG data, the retinal neurons that respond most actively to the defocus sign and are able to distinguish between positive and negative blurring are more localized in the near periphery of the retina, i.e. paramacularly,
· faster saturation of the progression from the optical center provides an earlier impact on the retina of the middle and far periphery with the maximum value of defocus,
· a larger amount of addition allows you to strengthen the defocus that affects the retina.
As a result, the optical advantages of the Perifocal-Ms lens provide conditions for increasing the effectiveness of therapeutic effects on the eye in progressive myopia.
Please, contact us:
Back to content