One common question practitioners ask when
I lecture on dry eye management is, Which punctal occluder should I
use on my dry eye patients? I usually weigh three primary factors
when selecting punctal plugs for any given patient: lid
configuration, ease of removal and cost.
My answer
assumes that the patient has undergone a thorough dry eye workup
revealing some tear production, but not enough to adequately protect
the ocular surface. It also assumes that the patient has reported a
definite benefit from temporary occlusion with dissolvable implants.
Choosing the Right Plug
Lid or
punctal configuration is probably the most important factor. I often
find it helpful to evaluate the profile of the eyelids from the
lateral aspect, using low magnification and swinging the observation
system to the side. If the lid/puncta are relatively vertical (not
rolled in) so that the puncta are in apposition to the conjunctival
surface, I opt for EagleVision plugs such as the Super Eagle. A
number of different variants of this design are available.
I
personally prefer Odyssey Medical's Parasol. As the name suggests,
the nose is configured like an umbrella, so it collapses during
insertion but then expands back to its original shape after it's
within the ampulla of the puncta. This design seems to have fewer
issues with falling out spontaneously, and Odyssey replaces any plug
that falls out within 30 days of implantation at no charge. The
company has redesigned the plugs with a flat dome; even if they rub
slightly on the conjunctiva, they're better tolerated than plugs
with a higher profile dome.
One
benefit of all domed designs is ease of removal if, for some reason,
it becomes necessary to explant the plug.
When
patients present with puncta that are in frank apposition to the
globe, I prefer an intracanalicular plug. Three choices are
available. The Herrick plugs (Lacrimedics, Inc.) are now fabricated
in an opaque material, so it's very easy to transilluminate the lid
and see if they're still in place. I find Herrick plugs easy to
insert, and there's very little problem with them falling out. But
if you need to remove a Herrick plug, the procedure can be difficult
for doctor and patient alike. In some cases, we've simply been
unable to irrigate them out of the lacrimal drainage system.
The
SmartPlug (Medennium, Inc.) is a 9mm acrylic rod before placement
into the undilated punctum. Once you insert a portion of the rod
inside the punctum, body temperature causes the rod to shrink in
length and expand in width to form a soft, gel-like plug. SmartPlugs
aren't difficult to insert, but they are fragile and easily broken,
and some practitioners find that the packaging system isn't very
doctor friendly. SmartPlugs require a certain amount of body heat to
make the polymer shrink, and in older individuals it may be
necessary to hold a warm compress on the eyelid to encourage
shrinkage. I find them easier to remove than the Herrick plug;
simply irrigate with warm saline. Unfortunately, the literature
reports increased incidence of canaliculitis with the SmartPlug.
The Oasis
Medical Form Fit plug has a more user-friendlier, pre-loaded
inserter packaging system. When dry, the plug is 3mm long and 0.3mm
wide, but its volume expands nearly 20 times when hydrated by the
tears. Similar to the SmartPlug, the Form Fit is rather easy to
remove with saline irrigation.
Using Punctal Plugs Profitably
Cost is
unfortunately a real factor in punctal plug implantation. For
instance, Medicare pays providers for the procedure, but not for the
plug itself; we are reimbursed the same amount whether the plug
costs us $15 or $50. Plugs are available in bulk at significantly
reduced prices; you may want to keep this in mind when deciding
which plugs to incorporate into your practice.