rules!!!

[haya]

Question time!!

I understand the concept of 'with the rule' astigmatism and 'against the rule' astigmatism BUT, if the situation is against the rule, and the horizontal meridian is steeper, then would the 'K' (in keratometry) value be greater in the horizontal meridian???

Thanks anyone,

haya :hammer: head

[mullo]

Keep it simple;

WTR astigmatism-the cornea will have a steep vertical meridian and a flat horizontal one

ATR- the opposite


To answer your question, yes. The greater the K, the steeper the meridian....Mullo :)

[haya]

:cheers: mullo

i feel a bit sheepish now for posting a thread like that!!!

thanks a lot

haya

[chip anderson]

Low K is always the longest meridian of the cornea no matter where it is. However when you are trying to regulate movement and centration you must concider the each meridian and it's location. If you want x amount of centration horizontally, you must use y amount of radius/diameter at that meridian. If you want x amount of movement in a given meridian, you must allow y amount of clearance (looseness) at that meridian.

Powers must be adjusted for the amount of steep or flat in each meridian.

If this is not clear, reply.

Chip:hammer:

[haya]

Originally posted by chip anderson

If this is not clear, reply.

Chip:hammer:
Actually that is more information than I needed but it is greatly appreciated although you have touched on something that has gone WAY over my head!! I kinda understand where you are coming from though.

IF THIS IS NOT CLEAR, REPLY!!!!!

Thanks Chip!!

haya :hammer: head!!

[mullo]

Never feel sheepish. Simple things allude us all from time to time. That is why Steve has this board, to provide help when we have
questions. Also to make our wives mad at us for being on the CPU all day long...........Oh, Oh, wife's coming, gotta go...Mullo


;) ;) ;)

[haya]

Originally posted by mullo
Never feel sheepish.
Well it's a good thing i didn't mention that i am originally from Wales!!!! Oh hold on, you are Canadian so you may just have no idea of what I am going on about...

:eek: Oh dear, have i said too much???!!!

:bbg: haya

p.s. :cheers: mullo

[Maria]

I know what you are referring to!:bbg:

[John R]

and wooliee jumpers :bbg: :bbg:
Haya is that what you shout................

[haya]

hey!!!

I was counting on you guys to keep shtum!!!!

:bbg: :angry: :bbg:

haya :hammer: head

[Maria]

Isn't there something about velcro gloves?



And yet again, Darryl's intellectual oasis is ruined by me :)

[Jo]

Darryl's intellectual oasis???

Maria,

You need a sight map. This was haya and chip's intellectual oasis. You thought you were sidetracking the wrong thread.

(Very "punny" of me switching sight for site; don't ya think? Definitely nap time.)

[mullo]

Hey Jo!! What about me?? I was second to be part of the oasis............Mullo :drop:

[Jo]

Originally posted by Jo
Darryl's intellectual oasis???

Maria,

You need a sight map. This was Mullo, haya and chip's intellectual oasis. You thought you were sidetracking the wrong thread.

(Very "punny" of me switching sight for site; don't ya think? Definitely nap time.)

mea culpa
:)

[Darryl Meister]

Originally posted by Jo
Maria,

You need a sight map. This was haya and chip's intellectual oasis. You thought you were sidetracking the wrong thread.

I think that Maria was referring to the Ophthalmic Optics forum, as a whole.

And, yes, she has ruined our oasis again. But I'll forgive her, because she is British.

Best regards,
Darryl

[Maria]

May I refer you to the 'Trivex' thread, this forum, second page, post four, by a Mr D.J. Meister. :)

[Jo]

Yes, it would be more like Maria to be shooting for the grander scale of the whole forum. But that is what we like about her!