Is 8.4 a base curve?
Is 8.4 a base curve?
Studies show that a single base curve of 8.4mm managed a “good or better” fit in approximately 90% of individuals,1 and base curves of 8.4mm and 8.6mm together encompassed 98% of individuals….
| LENS | BASE CURVES AVAILABLE (mm) | DIAMETERS AVAILABLE (mm) |
|---|---|---|
| 5 | 8.6 | 14.0 |
| 6 | 8.5, 9.0 | 14.2 |
| 7 | 8.4, 8.8 | 14.0 |
| 8 | 8.7 | 14.2 |
What is normal eye base curve?
Typical base curve values range between 8.0 and 10.0 mm, though it can be flatter (from 7.0mm) if you have a rigid gas-permeable lens. A person with a higher base curve number has a flatter cornea (the clear, front surface of the eye) compared to someone with a lower base curve number, which indicates a steeper cornea.
What is base curve of cornea?
The base curve is the radius of the sphere of the back of the lens that the prescription describes (the lower the number, the steeper the curve of the cornea and the lens, the higher the number, the flatter the curve of the cornea and the lens).
How do I choose the right base curve for contacts?
Figuring out the proper base curve based upon Rx is fairly simple: Plus Power – Use the Spherical Equivalent (Sphere power plus half the cylinder power) and add 4.00 diopter to that. Example – Rx of +2.50, the base curve will be approximately 6.50.
What contacts have a 14.5 diameter?
Contact Lens Base Curves and Diameters
| CONTACT LENS | POWER (SPH) RANGE | DIAMETER |
|---|---|---|
| Acuvue Oasys | +8.00 to -12.00 | 14.0 |
| Acuvue Oasys 1 Day | +8.00 to -12.00 | 14.3 |
| Acuvue Oasys for Astigmatism | +6.00 to -9.00 | 14.5 |
| Acuvue Oasys Presbyopia | +6.00 to -9.00 | 14.3 |
Is there a big difference between 8.4 and 8.8 base curve?
The 8.4mm base curve is still the likely best fit for the majority of eyes. In instances when the 8.4mm lens is too steep, the 8.8mm lens allows a flatter option. This is more likely needed in smaller eyes, and possibly in some very flat corneas.
What is a normal eye diameter?
The size of a human adult eye is approximately 24.2 mm (transverse) × 23.7 mm (sagittal) × 22.0-24.8 mm (axial) with no significant difference between sexes and age groups. In the transverse diameter, the eyeball size may vary from 21 mm to 27 mm.
What is the normal corneal diameter?
Results: The average corneal diameter was 11.71 +/- 0.42 mm. The average corneal diameter was 11.77 +/- 0.37 mm in males compared with 11.64 +/- 0.47 mm in females. The resulting normal ranges were 11.04 to 12.50 for males and 10.70 to 12.58 mm for females.
Does base curve affect vision?
The base curve of a lens may affect certain aspects of vision, such as distortion and magnification, and wearers may notice perceptual differences between lenses with different base curves. Consequently, some practitioners may specify “match base curves” on a new prescription.
What is the most common base curve for contacts?
How does base curve affect vision?
Can I wear contact lenses with different base curve?
Can I order contact lenses with a different base curve? You should never order contact lenses with a base curve that is different from your prescription. This can damage your eyes and cause problems with vision.