Vision - accommodating iols

Author

accommodating iols

William Stacy

2005-05-24, 8:59 am

Neil Brooks wrote:
>
> Scared.
>
> 1) No *data* indicating it will end accommodative spasm if it's of
> refractive etiology. Theoretically, it could make it worse. I don't
> *believe* the accommodative system ever gives up. I think that the
> most it does is goes 'dormant.'

I agree, having these non-accommodating iols for 5 months now, I'm
pretty sure my ciliary muscles are still working, even though it's not
having any effect on the silicone lenses.

If it truly gave up, how could
> presbyopes regain lost accommodation using accommodating IOLs?

They get a little, not much, from lens movement only.

I just
> think--if one never had symptoms associated with accommodation--one
> will never will have symptoms, even with fixed IOLs in place. Doesn't
> mean the proximity-induced accommodation isn't at play. I'd welcome
> discussion on this (since it's just my theory)....

I changed the thread name because it is an interesting topic and might
get some play.

>
> 2) I have *severely* dry eyes, *barely* managed with punctal cautery *
> 4 and frequent drops. Cataract surgery (PubMed) tends to decrease
> TBUT by 2.5s and Schirmer's by 2.5mm, on average. Scared. Very
> scared.

I believe that in the hands of a very skilled surgeon, this effect can
be minimized. It sounds like you have much to gain. What are your
numbers? (refraction, age). I mean you'll still have dry eyes, for
sure, but the optical advantage is large. One of the advantages of
being myopic dr. leukoma forgot, and I just remembered it. High
hyperopes have those pesky ring scotomata when they're wearing strong
glasses. I bet you'd like to give those up...

bill

w.stacy, o.d.

Neil Brooks

2005-05-24, 8:59 am

William Stacy <wstacy@obase.net> wrote:

>Neil Brooks wrote:
>
>I agree, having these non-accommodating iols for 5 months now, I'm
>pretty sure my ciliary muscles are still working, even though it's not
>having any effect on the silicone lenses.
>
>
>They get a little, not much, from lens movement only.

But it's those pesky ciliaries flexing the lens, no? I'd like mine to
'take 5.' Atropine b.i.d. was working, but the side effects were
unmanageable . . . and it was nibbling away at my corneas :-(

>
>I changed the thread name because it is an interesting topic and might
>get some play.
>
>
>I believe that in the hands of a very skilled surgeon, this effect can
>be minimized. It sounds like you have much to gain. What are your
>numbers? (refraction, age).

Age: 41.

Wavefront Rx:

SPH CYL AXIS
OD 8.44 -1.71 89
OS 7.95 -1.92 69

>I mean you'll still have dry eyes, for
>sure, but the optical advantage is large. One of the advantages of
>being myopic dr. leukoma forgot, and I just remembered it. High
>hyperopes have those pesky ring scotomata when they're wearing strong
>glasses. I bet you'd like to give those up...

I still wear the soft toric contacts about 15hrs/day. I do this
because:

a) Sharper vision, plain and simple. Can wear (any of my dozen pairs
of) readers over them, when necessary

b) The contacts are full (Atropinized) cycloplegic Rx. For some
reason, my eyes will relax a bit for the cl's, but not the specs (so
the spec Rx is ~2d less plus)

c) Hyperopes accommodate less with cl's than with specs; myopes, the
opposite

d) cl's allow me to wear my Panoptx total-wraparound sunglasses when
outside (and, generally, give me more access to things that ameliorate
effects of light, wind, glare, etc.)

The only thing I currently *don't* have corrected (it is in my specs)
is my exo-. I'm about 6-8d, IIRC . . . which obviously drives
additional accommodation.... Can't put that much prism in full-wrap
sunglasses, to my knowledge. (I've had three strabismus surgeries.
Congenital esotrope).

I can *manage* the dry eye now. A material reduction in TBUT or
Schirmer's and I'm in trouble. Relief from spasm is a very appealing
concept, but it's still an unknown.

I still view myself as having much to lose. The walls have moved in
on me dramatically over the years, but I'm still creating a life
within. Move those walls in too much more, and I'm not sure what
would be left....

Risk . . . risk.

Neil Brooks

2005-05-24, 5:57 pm

William Stacy <wstacy@obase.net> wrote:

>Neil Brooks wrote:
>
>Strong medicine. Never heard of such a case, but I've often wondered if
>the ac/a ratio was driven more by the rectus muscles than the other way
>around (in which case it should be called the a/ac ratio)...

Interesting.

Started with Mydriacyl, 3x/week. When the spasm started to return, we
moved me up to nightly. When that wouldn't stave it off, moved to
Cyclomydril, then 2x/week Atropine. Finally, I read that Atropine had
a bi-phasic half life. The first was only hours after instillation --
about when the symptoms started to return. We then went with the bid
routine.

>
>Perfect candidate for iols, along with maybe a couple of little
>astigmatism relaxing incisions. You would be giving up a few years of
>accommodative ability, but sounds like you'd just as soon do that anyway...

Then, of course, there's the question of yet more dryness from the
lri's.

>
>Obviously. Same effect with iols. I'm a bit surprised you can do that
>with all the dryness. What brand?

Can't recall. I'll have to see if I can find out.

>
>Lends more fuel to my idea that maybe it's your convergence driving the
>accommodation rather than the other way around.

Having watched a movie at my friend's house (60" rear-projection TV.
Seated about 8' away) last evening, I tend to agree. Holding 10d must
drive significant accommodation. I was whupped when we left. Flat
out whupped.

>
>It would be tough. Do you need more or less prism at near than far?

Just checked the chart. Looks like it's 10d; 9 at near.

>I think you could manage any reduction of tbut,

Last two readings were noted, simply, as "< 5s." That's with the full
cautery.

>I mean you're probably
>going to get dryer anyway with age.

Then I'll stop aging. There. That was easy ;-)

>Lots of things you can use, maybe
>more often than now, but managable.

Hmm.

>
>To me, the advantages far outweigh the risks. The optical gains for you
>are tremendous (as you already know with the CLs), and you could always
>wear one of those new silicone CLs as a bandage lens if push came to
>shove. And of course you'd never have to worry about getting cataracts...

But that addresses solely the sicca component. I already have ciliary
hypertonicity and a tremendous propensity to spasm. What if the
accommodative spasm just goes nuts and tries its hardest to break
these IOL's (by firing and firing and firing) without burning out? So
far, I've found nobody who says it *can't* happen, and several who
feel it to be a "real possibility."

That's the real issue. If I do IOL's -- especially with a 5.5 or 6mm
OZ (with my 7mm pupil), and have to go to "emergent" Atropine to break
an even more tenacious spasm, I'll have all the same halo (et al)
effects that a bad lasik job gives, plus chromatic abberations,
photophobia, and corneal munching that come with chronic use of
cycloplegia.

Nobody can say it's a 1%, 2%, 5%, or 10% risk. I haven't found
anybody who knows.

That's the fear....

Grateful for the help . . . as always.

William Stacy

2005-05-24, 5:57 pm

Neil Brooks wrote:

> Then, of course, there's the question of yet more dryness from the
> lri's.

Well I experienced a little dryness day 1 post-op, but that was all. Not
sure if that sensation came from the 3mm cataract incision or the
relaxing incisions, or both. Anyway, all incisions are peripheral, where
dryness irritataion would be less noticeable than centrally.
>
>
> Having watched a movie at my friend's house (60" rear-projection TV.
> Seated about 8' away) last evening, I tend to agree. Holding 10d must
> drive significant accommodation. I was whupped when we left. Flat
> out whupped.

Have you tried doing anything with one eye patched? That would
completely eliminate any convergence issues. Worth a try.

> Just checked the chart. Looks like it's 10d; 9 at near.

Experiment with a patch at far and at near. Could be revealing as to
what's driving what.
>
Then I'll stop aging. There. That was easy ;-)

Right on.

> But that addresses solely the sicca component. I already have ciliary
> hypertonicity and a tremendous propensity to spasm. What if the
> accommodative spasm just goes nuts and tries its hardest to break
> these IOL's (by firing and firing and firing) without burning out? So
> far, I've found nobody who says it *can't* happen, and several who
> feel it to be a "real possibility."
>

Well I don't think the ciliary muscle is physically capable of breaking
an iol. Not that it might not be strong enough, but that it is just too
large in diameter when fully contracted to ever "squeeze" the iol.
Remember, the muscle is connected to the lens capsule with suspensory
zonules, not directly physically in contact with it.

> That's the real issue. If I do IOL's -- especially with a 5.5 or 6mm
> OZ (with my 7mm pupil), and have to go to "emergent" Atropine to break
> an even more tenacious spasm, I'll have all the same halo (et al)
> effects that a bad lasik job gives, plus chromatic abberations,
> photophobia, and corneal munching that come with chronic use of
> cycloplegia.
>
Actually, I think it's common for pupils to end up smaller post iol
implantation. Not sure why this is, but mine seem smaller now, est.
from 6 down to 5, maybe 5 to 4 or so; I'll check.

> Nobody can say it's a 1%, 2%, 5%, or 10% risk. I haven't found
> anybody who knows.

Right, everything would be a guesstimate. You're the one who has to
pull the handle, or press the button. Let me know what the patch does
or doesn't do, and try it on each eye.

w.stacy, o.d.

Neil Brooks

2005-05-24, 5:57 pm

William Stacy <wstacy@obase.net> wrote:

>Experiment with a patch at far and at near. Could be revealing as to
>what's driving what.

It's been a while. I think you're right: it's time. Drug store, here
I come. I hope they come in designer colors, bullseyes, or simple
spirals these days. Basic black . . . I don't know....

>
>Well I don't think the ciliary muscle is physically capable of breaking
>an iol. Not that it might not be strong enough, but that it is just too
>large in diameter when fully contracted to ever "squeeze" the iol.

Sorry. Bad metaphor on my part. What I should have said is this:
given that there is no *known* neurologic etiology to *my* ciliary
spasm (and given my high refractive error), my assumption is that it's
all refractive in nature. My accommodative system has worked itself
stupid trying to overcome blur (or near-reflex stimuli). In the
process, the ciliaries have hypertrophied, exacerbating the whole
thing.

That's all getting worse as I move into presbyopia (now). The
hypertonicity seems to be increasing. I'm more symptomatic, even
without doing near work, than ever before. I believe that it's the
accommodative system responding to the inchoate lenticular
inelasticity. My focusing system is saying, "What? You don't want to
flex any more?? What if I just double the ciliary push, then? How do
you like that"

It's ugly. Ciliary petulance and machismo at its worst.

Hasten that process--by giving it something that it *can't* alter (a
monofocal IOL) and there's a couple ways it could go:

1) It could "burn out" and give up. Case closed.

2) It could work and work and work and work, increasing my dizziness,
pain, and fatigue, without ever burning out. Ouch.

Nobody's ever done it . . . except one case where an MVA left a young
man with spasm from neurologic issues.

http://snipurl.com/f1zh

His resolved totally. His ciliaries, though, had no evidence of
hypertrophy. Mine are tenacious little buggers. How does that
translate? Unknown.

>Actually, I think it's common for pupils to end up smaller post iol
>implantation. Not sure why this is, but mine seem smaller now, est.
>from 6 down to 5, maybe 5 to 4 or so; I'll check.

Also interesting. Wonder why that is....

>
>Right, everything would be a guesstimate. You're the one who has to
>pull the handle, or press the button.

Yup. And -- after three strabismus surgeries and years of involvement
in all of this -- I'm a bit trigger-shy.

>Let me know what the patch does or doesn't do,
>and try it on each eye.

Totally benign and diagnostic idea. I shall.

Thanks again. Did I mention that it's nice to have you back? ;-)

William Stacy

2005-05-24, 5:57 pm

Neil Brooks wrote:

>
> It's been a while. I think you're right: it's time. Drug store, here
> I come. I hope they come in designer colors, bullseyes, or simple
> spirals these days. Basic black . . . I don't know....

Hell, forget the drug store. Take a roll of electrician's tape and
black out that mother. I'm on a roll tonight...

w.stacy, o.d.