Significance of the "astigmatism" figure

gaiscioch

I have two boxes of contact lenses from Specsavers. According to the box:
The left eye is:
BC: 8.6
DIA:14.1
PWR: -5.50

The right eye is:
BC: 8.6
DIA: 4.3
PWR -5.00/-0.75x180

The left eye box's brand name says 'easyvision: now with handling tint'
The right eye box's brand name says 'easyvision umere toric'.

Presumably '-0.75x180' is the toric figure and thus represents the degree of astigmatism in the right eye. Is this a significant difference?

I had been using the non-toric lenses for years and I was quite happy with them. My new prescription however has this toric figure in one eye. It is a less comfortable lens and also more expensive if I want to continue with the daily disposable (the monthly toric seems OK pricewise). Essentially, with this degree of astigmatism I'm wondering would there be any downside to just reverting back to the non-toric prescription for both eyes?

PS: When it is said that the toric lens "corrects" astigmatism, does this just mean while you're wearing them, or does it mean that if you wear them for a sufficient period of them you will have the problem corrected and not need that toric lens (for instance, some kids who wear glasses don't need them after a few years)

Sprog 4

I'm no optician but astigmatism as fas as I know, means that the surface of your eye isn't a sphere but rather a kind of rugby ball shape. This means that it has a different power in perpendicular directions (in your case 90 degree and 180 degree). So in your case your right eye is actually -5.75 horizontally and -5.00 vertically while your left eye is -5.50 in all directions (it is a sphere).. It is of course better to correct astigmatism with a toric lens but since -5.50 is in between -5.75 and -5.00 it would be very close to correcting both powers of the right eye so it should be ok to wear the -5.50 in that eye too I would have thought, especially if the toric is causing discomfort. Do you notice any difference in quality of vision when you wear the -5.50 in your right eye?

'Correcting' means it will correct the vision only while you wear it. If you have astigmatism (and most people do have some amount of it) your eye wont change shape back.

PS: Do you really have a giant left eye with a DIA (diameter) of 14.1? :P

gaiscioch

Sprog 4 wrote: »

I'm no optician but astigmatism as fas as I know, means that the surface of your eye isn't a sphere but rather a kind of rugby ball shape. This means that it has a different power in perpendicular directions (in your case 90 degree and 180 degree). So in your case your right eye is actually -5.75 horizontally and -5.00 vertically while your left eye is -5.50 in all directions (it is a sphere).. It is of course better to correct astigmatism with a toric lens but since -5.50 is in between -5.75 and -5.00 it would be very close to correcting both powers of the right eye so it should be ok to wear the -5.50 in that eye too I would have thought, especially if the toric is causing discomfort. Do you notice any difference in quality of vision when you wear the -5.50 in your right eye?

'Correcting' means it will correct the vision only while you wear it. If you have astigmatism (and most people do have some amount of it) your eye wont change shape back.

PS: Do you really have a giant left eye with a DIA (diameter) of 14.1? :P

Thanks so much for that. I didn't notice any difference at all when I wore the toric lens, but I'm open to the possibility that sometimes my attention would need to be drawn to a particular benefit before I'm actually aware of it, if that makes sense. I'm back wearing my ordinary lenses now and they're fine. Ooops re 14.1! All these numbers...