Today it�s widely recognized that Intraoperative
Floppy Iris Syndrome (IFIS) is caused by prior or current use
of tamsulosin hydrochloride (Flomax), and other alpha-blocking
medications such as Hydrin, Cardura and Uroxatral. Flomax
is commonly prescribed to treat the restricted urinary flow
that is symptomatic of benign prostatic hyperplasia; it works
by relaxing the smooth muscle in the bladder neck and
prostate. Unfortunately, because the iris dilator muscle
has the same alpha-1 receptor subtype as in the prostate, it
is also affected by these medications.
As
reported in 2005 by David F. Chang, MD, and John R. Campbell,
MD, the pupil often dilates poorly in patients taking alpha-1
blockers; IFIS is characterized by iris billowing and
floppiness, iris prolapse, and progressive constriction of the
pupil. These problems increase the incidence of posterior
capsule rupture�particularly when the surgeon has not
anticipated IFIS.1
Dr.
Chang, a clinical professor at the University of California,
San Francisco, and in private practice in Los Altos, Calif.,
notes that once the connection between floppy iris and Flomax
became clear, ophthalmologists voiced many different opinions
about how to manage the syndrome. �The most important lesson
here is that clinicians need to question patients
preoperatively about current or prior alpha-1 blocker use,�
says Dr. Chang. �Then they can be better prepared to manage
the iris intraoperatively. A second important point is that
the popular mechanical pupil stretching technique is
ineffective for IFIS�it can exacerbate the problem.�
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A Morcher pupil expansion ring
is used to hold a pupil affected by IFIS open wide
during cataract surgery. David F. Chang,
MD |
As additional
reports of IFIS surgical complications appeared, the question
of how to advise urologists arose. �Some ophthalmologists
suggested that patients should not be treated with Flomax
until after they�d had their cataracts removed,� notes
Dr. Chang. In order to determine whether a change of this
magnitude was really necessary, Dr. Chang organized a
multicenter, prospective study of Flomax patients
undergoing cataract surgery, to see whether
their surgeries would be negatively affected when the surgeon
knew that IFIS was a potential problem.
The 10
surgical practices in the study monitored 169 consecutive
Flomax patients over a seven-month period, tracking
outcomes and complication rates. The surgeons were allowed to
choose any one of four surgical strategies to manage
IFIS�preoperative atropine, Healon 5 viscomydriasis, pupil
expansion rings or iris retractors. �We found a very low
complication rate, with less than 1 percent posterior capsule
rupture,� says Dr. Chang. �In short, the data suggest that if
the surgeon can anticipate when IFIS is likely to occur, he or
she can use an alternate pupil management strategy and obtain
excellent results.� Dr. Chang will be presenting the
complete results of the study at this year�s American
Society of Cataract and Refractive Surgery meeting.
Choosing a Management
Strategy
Because a
number of strategies can be used to manage IFIS
intraoperatively, we asked several surgeons to talk about
their experience using the different options. �Currently,
management strategies can be divided into three broad
categories,� explains Dr. Chang. �One is
pharmacologic�manipulation of the iris using either
preoperative atropine or intracameral epinephrine or
phenylephrine. Another technique involves using Healon 5 for
viscomydriasis, sometimes in conjunction with a dispersive
agent to retard its evacuation. The third category is the use
of devices to hold the pupil open, such as a pupil expansion
ring or iris hooks.�
Dr. Chang
says it�s important for surgeons to recognize that IFIS can be
mild, moderate or severe, because a technique that works in a
mild IFIS case may not work as well if the problem is severe.
�In a mild case, the pupil may dilate quite well despite
Flomax use,� he observes. �In these cases there�s not a lot of
tendency for iris prolapse, and not much constriction; any of
the techniques may work well, including atropine and Healon 5.
In a severe case, however, there�s a strong tendency for
prolapse and the pupil constricts very quickly. Atropine
doesn�t really work well for these eyes.�
Dr. Chang
notes that preop dilation may provide a good clue about which
level of IFIS you�re dealing with. �If the pupil is very small
preoperatively, you should anticipate severe IFIS, and I would
favor iris retractors for these cases,� said Dr. Chang. �I
also use iris retractors instead of Healon 5 if the nucleus is
brunescent because of my preference for using high vacuum with
these eyes.�
Using Epinephrine
Joel
Shugar, MD, MSEE, medical director and CEO of Nature Coast
Eyecare Institute in Perry, Fla., says the idea of using
epinephrine to combat iris floppiness caused by IFIS occurred
to him in June 2005.
�Basically, Flomax is an alpha-1 adrenergic
blocker,� he explains. �Epinephrine is adrenaline, which is
the molecule that Flomax blocks. So it occurred to me that
using epinephrine intracamerally in a very high concentration
might be enough to overcome that blockade. Instead of trying
to make an end-run around the problem by using either hooks or
Healon 5 to deal with a floppy iris, this addresses the
problem directly: It makes the iris stop being floppy.
�Once I
had the idea,� he continues, �I used a pH meter to check the
acidity of American Reagent non-preserved, bisulphite-free
1/1000 epinephrine. By itself it had a pH of 3.13,
sufficiently acidic to damage the endothelium. However,
diluting it three-to-one with a mixture of three parts
BBS-plus to one part 4% nonpreserved lidocaine, or
�Shugarcaine,� brought the pH up to 6.9. We call the
mixture �epi-Shugarcaine.� �
Dr.
Shugar says this solution is ideal for him because he uses
Shugarcaine as an intracameral anesthetic in nearly every
case. �I�m adding the epinephrine to what I�m going to be
injecting anyway,� he explains. He adds that he injects the
mixture before the viscoelastic, because viscoelastic can
cause a painful retrodisplacement of the lens-iris diaphragm;
injecting the anesthetic first prevents the patient from
experiencing pain.
Asked how
much needs to be injected, Dr. Shugar says that under
ordinary circumstances he might use 0.5 cc of the
BSS/lidocaine mixture, but to prevent IFIS he injects 1 to 2
ccs of the epi-Shugarcaine. �This quantity always seems to be
effective,� he says. �I wait about 30 seconds before
putting in the visco. The iris loses its flaccidity or
floppiness very quickly, and additional dilation occurs
during the next one to two minutes, generally making the pupil
1 or 2 mm larger than it was before.�
Widely Effective
Dr.
Shugar agrees with Dr. Chang that IFIS can be mild, moderate
or severe, but says that in all of the cases in which he�s
used this strategy to manage the symptoms (approximately 20
cases at the time of this interview), it has been completely
effective. �All of the eyes that I�ve done had crystal-clear
corneas the next day, with 20/10 or 20/15 vision,� he says. He
adds that he has posted his results on the ASCRS Internet
discussion group, and 10 or 15 additional cases have been
reported by other surgeons. �In all but one of them, this
strategy was effective. In the one case in which it wasn�t
effective, the patient had a maximum pupil size of 2.5 mm
before the epinephrine, which could indicate that some extra
unknown factors were involved.
�In my
experience, this approach seems to be the answer,� he says.
�And epinephrine has the advantage that it can be instilled at
any time during a case, so if you�re surprised by symptoms
suddenly appearing, you can deal with it and proceed.�
Dr. Chang
agrees with the latter point, noting that in some cases the
pupil is reasonably well-dilated initially, but following
hydrodissection the pupil suddenly constricts. �In this
situation, where the capsulorhexis makes it more difficult to
place expansion devices, I�ve found that intracameral
epinephrine can really help,� he says. Dr. Chang notes that in
this situation iris retractors are still an option, but
advises caution: �If you do need to use iris retractors after
completion of the capsulorhexis, I�d recommend using a second
instrument like a Lester hook to push the pupil margin away
from the capsulorhexis edge. That way you can be absolutely
certain that you�re hooking the iris and not the �rhexis with
the iris retractor.�
Dr.
Shugar says he�s not aware of any downside to using
epinephrine to manage IFIS. �The epinephrine allows the
vast majority of cases to be treated as standard cataract
surgery, as if the patient had never used Flomax,� he says. He
notes that it�s also cost-effective, with epinephrine costing
less than a dollar a bottle. �I�m sure there will be a few
cases that require Healon 5 or iris hooks, but if you can
prevent a large percentage of those, I think that�s a great
solution.�
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Injecting Healon 5 into an IFIS
eye will dilate an undilated pupil and keep the iris
away from the cornea. However, it may necessitate
changes in capsulorhexis
technique. Douglas D.
Koch, MD |
Using Atropine
Samuel
Masket, MD, clinical professor of ophthalmology at the Jules
Stein Eye Institute, UCLA School of Medicine, says that when
first confronted with IFIS, one thing became apparent to him.
�In addition to the tendency for the iris to billow and try to
escape through incisions during surgery,� he says, �the pupil
became progressively smaller. The dilator muscle is weakened
by the alpha-1 blocker, so it doesn�t have as much
counter-traction against the pupil�s tendency to become
miotic.� Dr. Masket realized that the pupil coming down was
the biggest part of the problem. �If the pupil stays widely
dilated, it keeps the iris tissue out of the way of the
emulsifying probe. Iris floppiness doesn�t become as manifest,
and we tend to not have any problems.
�Traditional cycloplegics and iridoplegics, such
as Mydriacyl [tropicamide] or Cyclogyl [cyclopentolate], don�t
have the same iridoplegic strength as atropine,� he continues.
�So it made sense to use atropine to block the pupil as much
as possible to counteract the progressive miosis. This has no
effect on the billowing of the iris, but by keeping the pupil
as dilated as possible, its less likely that the iris will
interfere with removing the cataract.� So, Dr. Masket says he
began having Flomax patients use one drop of atropine 1% three
times a day for the two days before surgery, and once again on
the day of surgery.
Dr.
Masket says the size of the pupil at the beginning of surgery
determines how he will proceed. �If the patient comes into
surgery with a pupil dilated in excess of 6 or 7 mm in
response to atropine and the other iridoplegic agents
administered prior to surgery, the pupil will generally not
come down during the procedure,� he explains. �In this case, I
start the surgery without the use of hooks and
anticipate that the surgery will be nearly routine. If
the patient has less than 6 mm of dilation, I use iris
hooks from the beginning and surgery tends to progress
routinely. Should the pupil become progressively smaller
during surgery, then I�ll stop and place iris hooks, or if
available, switch to the Healon 5 method.� [For more on
this, see below.]
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Reusable iris retractors can be
placed in a diamond configuration. Because an IFIS pupil
is very elastic, even maximal stretching doesn't cause
sphincter damage. David
F. Chang,
MD |
Potential
Drawbacks
Dr.
Masket notes two potential drawbacks to using atropine for
this purpose. �First,� he says, �a patient who has very
reduced bladder function or a very enlarged prostate could go
into acute urinary retention if the Flomax is stopped and
atropine is applied topically. For that reason, it�s essential
that the Flomax be continued. In any case, we know that
stopping Flomax is of little or no benefit in terms of
reducing IFIS.� He notes that patients who have stopped
Flomax have either had prostate surgery or are on
another medication.
�The only
other drawback is very minor, and that is that there�s a
tendency for the patient to stay dilated anywhere from four to
10 days after surgery,� he continues. �We do like to have the
pupil return to normal as quickly as possible to aid visual
function. However, this is relatively unimportant because the
patient is pseudophakic at this point, so the loss of
focusing isn�t really a problem. Also, these patients tend to
return to normal dilation more quickly than patients
using atropine who haven�t been on Flomax.�
Dr.
Masket says he suspects atropine may not be able to
overcome the tendency of the pupil to get smaller during
surgery when a patient has a complete or near-complete
alpha-1 blockage at the dilator muscle. �However, if the
blockage is less than 100 percent,� he says, �atropine can be
a very effective adjunct, and surgery can be routine, or
nearly routine. I�ve used this approach on roughly 20 cases;
about two-thirds did not require the use of iris hooks.�
Using Viscoelastic
Douglas
D. Koch, MD, professor of ophthalmology at Baylor College of
Medicine in Houston, prefers using Healon 5 to control the
iris when confronted with IFIS. �Healon 5 has the highest
viscosity of any of the available viscoelastics,� he says.
�Injected into an IFIS eye it will dilate an undilated pupil
and keep the iris away from the cornea. As long as it�s not
aspirated, Healon 5 does a wonderful job of preventing the
iris from billowing, prolapsing and otherwise
misbehaving.�
Dr. Koch
says he uses Healon 5 during the entire case, but he
acknowledges that some surgeons don�t like to use it
during capsulorhexis. �It�s difficult to do a needle
capsulorhexis with Healon 5,� he says, �because its hard to
fold the capsule over and drag it through the highly viscous
material. Capsulorhexis forceps work better under these
conditions. Likewise, for hydrodissection you have
to create a little path so the fluid can exit; otherwise it
can build up in the capsular bag, creating a capsular
block that can jeopardize the posterior capsule.�
Dr. Koch
says it�s not necessary to use Healon 5 exclusively to make
this work. �If the pupil is adequately dilated at the outset,
you can use whatever viscoelastic you�re accustomed to in the
initial phases of the surgery,� he explains. �Also, if you�re
not comfortable doing your �rhexis and hydrodissection under
Healon 5, you can use a soft-shell technique in which the
Healon 5 is injected more anteriorly to protect the cornea,
while you place something beneath it that�s much less viscous,
possibly even BSS.�
Disassembling the Nucleus
For many
surgeons, the hard part about using Healon 5 is disassembling
the nucleus without being able to use high flow and vacuum.
�When you�re doing phacoemulsification under Healon 5 you need
to keep your parameters at modest levels to prevent aspiration
of the viscoelastic,� admits Dr. Koch. �I�ve found it
effective to keep the vacuum at 215 mmHg or lower, with a flow
rate no higher than 25. I usually keep it around 20.
�To
disassemble the nucleus under Healon 5,� he continues, �I like
to use a modified stop-and-chop approach in which I sculpt a
groove, break the nucleus in half, rotate it 90 degrees, and
then mechanically break a piece off of the distal half using a
Nagahara chopper and the phaco tip. I do this mechanically,
without any flow or vacuum, even if I�m not using Healon 5.
Then it�s easy to engage that piece with the phaco tip,
initiate flow and vacuum, and remove it. It�s also easy to
remove the remaining portion of that half of the nucleus
because it can be directly aspirated, brought forward, and
then chopped in a more standard fashion.� Dr. Koch notes that
this is a derivation of the slow-flow technique developed by
Robert H. Osher, MD, but with higher settings.
�When you
use higher flow and vacuum settings to remove the cortex, you
may aspirate some of the Healon 5, causing the pupil to come
down,� notes Dr. Koch. �This can be disconcerting or even
alarming for the surgeon. But all you have to do is reinject
the H5 and the pupil comes right back up.� Dr. Koch says that
he avoids this problem by using bimanual irrigation and
aspiration, which makes it easy to get under the capsule and
remove cortex from any quadrant, even if the pupil is
relatively small.
Dr. Koch
adds one important caveat about using Healon 5. �You must go
underneath the implanted intraocular lens to remove it,� he
says. �I always use a coaxial irrigation and aspiration
handpiece to do this. Using this technique, you can readily
see the Healon 5 being removed. In my experience, other
techniques are not sufficiently reliable.�
An Effective Alternative
Overall,
Dr. Koch says that having to use low flow and aspiration
hasn�t been an impediment. �It�s tougher if you�re dealing
with a denser nucleus,� he admits, �but once you get that
first crack, everything�s fine. You just have to proceed
slowly and cautiously.�
Dr. Koch
acknowledges that if Dr. Shugar�s epinephrine system is as
effective as injecting Healon 5, it would be easier for many
surgeons because it doesn�t require altering the flow and
vacuum settings a surgeon may prefer to use. �I think the
epinephrine approach is worth trying,� he says, �although I
have a feeling there will be eyes in which it won�t work. In
some cases the dilator muscle may have atrophied so much that
there won�t be enough muscle left to stimulate.
�I like
the Healon 5 approach because to me it�s faster and at least
as safe as using any of the other options,� he continues. �I
proceed with very little delay even though the settings are
reduced somewhat, and the Healon 5 always leaves a beautiful,
round pupil. Iris hooks are fine, but they take a fair amount
of time to insert and position, and in 25 cases I�ve never had
to resort to them. Healon 5 is also less expensive because it
simply involves substituting one viscoelastic for another.
�Healon 5 has been very
effective in my hands,� he concludes. �It�s worked every
time.�
Rings and Retractors
Dr. Chang
talked about his experience using pupil expansion rings and
iris retractors. �Three companies make pupil expansion rings,�
he says. �Morcher and Milvella make plastic rings. You need a
special injector to insert them, which is costly but reusable.
Another alternative, the Graether Pupil Expansion System
from Eagle Vision, is made of silicone and comes with a
disposable injector system.�
Dr. Chang
says he�s used all three rings, and they all work very well
for IFIS. He notes, however, that there are two situations in
which pupil expansion rings can be difficult to insert. �One
is when the patient has a shallow anterior chamber,� he
explains. �The other is when the pupil is so small that it
makes threading the expansion ring into place overly difficult
and traumatic. In those situations, iris retractors are much
easier to use.� Dr. Chang also notes the fact that the surgery
center is not reimbursed for these devices has probably
limited their popularity.
Dr.
Chang�s current preference is to use iris retractors. �I place
them in a diamond configuration,� he notes. [See photo,
page 62.] �I insert one through a stab incision just
posterior to the clear corneal phaco incision, as previously
described by Drs. Oetting and Omphroy.2 This pulls
the iris downward and out of the way, increasing the exposure
right in front of the incision.
�With
practice, you can insert and remove iris retractors very
quickly,� he says. �I find that it adds minimal time to the
case, while making the entire procedure easier and
stress-free. Unlike using Healon 5 to manage the iris, this
technique allows you to employ high vacuum, and the pupil
expansion is 100-percent reliable.�
Dr. Chang
observes that surgeons sometimes hesitate to use iris hooks
for fear of damaging the iris sphincter. He says that although
that can happen when a fibrotic pupillary margin is subjected
to excessive stretching with iris retractors, it�s not a
problem in this situation. �With IFIS the pupillary margin is
very elastic and not fibrotic,� he says. �You can stretch it
maximally and it doesn�t cause permanent sphincter damage or
permanent mydriasis.�
In terms
of which iris retractor Dr. Chang prefers to use (he has no
financial interest in any of them) he notes that disposable
retractors made of nylon have been available for many years,
but he now prefers reusable, autoclaveable polypropylene iris
retractors, such as those available through FCI and Katena.
�These are a little thicker and stiffer than the nylon
retractors, but still flexible, like an IOL haptic,� he notes.
�That�s what makes them more durable and allows you to keep
reusing them. It also makes them easier to handle and
insert, and it�s easier to hook the pupillary margin
because they�re slightly more rigid than the nylon ones.� He
adds that being reusable helps to make the polypropylene
retractors cost-effective.
Is One Method Preferable?
�When
dealing with IFIS, it�s common sense that you want the pupil
to remain as dilated as possible,� notes Dr. Chang. �But right
now, which option you use to accomplish that is a matter of
personal preference. We don�t have any studies that say you
get better outcomes with one technique or the other.�
Dr.
Masket adds that in his view, the use of any of these agents
does not preclude the use of any of the others. �Atropine
blocks the sphincter muscle,� he says. �Epinephrine stimulates
the dilator muscle. The hooks and Healon 5 are mechanical
devices that hold back the sphincter of the iris and tampanade
the movement of the peripheral iris tissue.
�Iris
hooks and Healon 5, used correctly, will work 100 percent of
the time,� he continues. �The pharmacologic agents won�t work
100 percent of the time, but they may prevent the need for the
hooks or Healon 5, which add significantly to the expense of
the surgery. The bottom line is that they can all be used in
conjunction with one another. They�re all part of the
armamentarium.�
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