Tuesday, January 22, 2013

My Experience With ICL (Implantable Collamer Lens)

This entry is a little break from the norm.  Rather than bring you some attempt at insightful commentary on whatever comic book or movie has last tweaked my fancy, this one is a little more personal and a little more technical, so bear with me.

Recently, after consult with my eye doctor and a specialist in the field, I made the decision to have contact lenses permanently implanted in my eyes. I've worn glasses since the third grade, and I couldn't function without corrective lenses.  The idea of waking up in the morning without fumbling around for the damn things seemed like the best thing one could wish for.

The procedure, known by most by the equipment nomenclature, is referred to as "ICL", which stands for Implantable Collamer Lens.  In the procedure, a lens very similar to a contact lens is implanted behind the iris, but in front of the eye's natural lens.  It's completely invisible to the naked eye, and corrects for nearsightedness.  It's a procedure based on, and somewhat similar to, the surgery used to treat cataracts.

There are several advantages and disadvantages between ICL and the more common Lasik procedure for correction of myopia.  Lasik is a procedure where a laser is used to re-shape corneal tissue (the outside layer of the eye, that you can touch with your finger).  Lasik is cheaper, and by nature less invasive...nothing is inserted into the eye.  This eliminates the small chance for some side effects such as cataracts that can occur when anything is implanted into the eye. Modern Lasik procedures can also correct for astigmatism, which is what you get when there are irregular imperfections in the shape of the eye and it's focusing mechanisms that can't be compensated for with a single, across-the-board prescription. The ICL version of astigmatism correction isn't approved yet.  Lasik is also cheaper than ICL by a fair margin, although they're in the same ballpark.

There are some advantages to ICL that Lasik doesn't have.  Lasik removes eye tissue to produce a new shape, like whittling away at a sculpture.  You can't replace this tissue and start over.  While Lasik can be fine-tuned in one direction, giving you further correction, you can't really dial it back, whereas the ICL procedure is completely reversible.  ICL can also compensate for a wider range of prescriptions, and may be the only choice for correcting people whose corneas aren't the shape or thickness required for Lasik.

The way things stand now, most ophthalmologists will point toward Lasik for people who qualify, with ICL being the back-up for those who aren't Lasik suitable for whatever reason.

I was measured for suitability for both procedures.  My first visit to the ophthalmologist included a battery of tests to map the shape and thickness of my corneas, determine my prescription, and examine my eyes for suitability for the ICL implant.  The measurements came back okay for either procedure.  While my prescription is at the lower end of what they suggest for ICL, and my corneal thickness was more than adequate for Lasik (more on that later), my corneas were apparently flat enough that the doctor left both options open to me.  I liked the idea of a reversible procedure enough that I chose the ICL over Lasik.  They scheduled me for an additional consultation, where everything was re-mapped and re-measured, and from there I scheduled the first of two surgical procedures for the following week.  The entire process took place across about 6 weeks.

An ICL operation actually consists of two procedures.  In the first procedure, usually a week or so prior to the actual implant, a laser is used to cut a small opening at the edge of each iris (called YAG laser iridotomy).  This allows fluid inside the eye to flow among and around the implanted lens, which is necessary for proper placement.  The second procedure is the actual implant of each lens, where a small incision is made in each eye, the lens itself is folded for insertion and basically released into the pierced chamber and allowed to unfold in front of the eye's natural lens.

My Experiences:

I came in for my YAG iridotomy on a Tuesday, having taken the day off work to have the procedure.  The iridotomy was to be a simple procedure lasting a few minutes each eye, involving 5 quick and relatively painless jolts with a laser to create the necessary opening.  I had been told previously that I'd be getting a dose of Valium prior to, as a calming agent, as having one's eye cut with a laser freaks some people out.  Once there, however, I was assured this was not the case, and that Valium was usually not administered until the final insertion procedure.

Had I known what was coming, I'd have demanded their highest dose of whatever calming agent was available.

Before the iridotomy, they placed drops in my eyes designed to contract the pupil, then observed me in a dark room while I lay comfortably in a chair.  Once the drops had taken, I was escorted to the operating room.  I was seated upright on a stool and my head placed in a chin rest and headband apparatus similar to what an eye doctor uses for routine exams. I was directed to hang on to two stationary handles that looked like the joysticks on an old style arcade machine.  It was at this point that several obstacles concerning my physiology that made the iridotomy difficult became apparent:  Apparently, my eye sockets are fairly well-recessed, and I have a prominent chin.  Whether this indicates a large frontal lobe of the brain and facial features like those of my comic-book heroes, or if it is, instead, a throwback to my cro magnon ancestry, I'll leave you to judge.  My melon just didn't fit in the thingey real good.

The doctor, seated in front of me behind some sort of Jack Kirby-inspired mechanism of scientific endeavor, observed my eye through a system of telescopes, mirrors, and supremely bright lights, and began to announce, repeatedly, that my head must come forward.  He needed an angle coming from the side of the eye closest the bridge of the nose and moving outward, and the nose was in the way. The nurse, behind me, tried to comply with his increasingly distressed announcements by placing both hands behind my head and bearing down on it with at least a considerable portion of her own body weight.  The problem seemed, to me, entirely due to the rather unyielding steel head band and chin rest in direct contact with my inflexible, cro magnon skull, and further complicated with the fact that even if my skull were to give way and be forced entirely through the "rest", my nose would presumably move forward with it.  My head proved completely resistant to her efforts to shove it through the apparatus like a potato through a drain pipe, but the doctor needed a better angle, so the efforts continued.  I quickly gathered that the object was not to move the head forward, but rather, to cause the eye by compression of the skull to bulge forth in its socket. What else, by virtue of the transitive effect of the motion of the skull imparted to the nose, could they be trying to accomplish?

In the mean time, my eye was fitted with a monocle-like device, which was covered in gel and placed directly on the eye around the iris.  This, I think, was to facilitate coupling the laser to it's target, and give a scope through which the doctor could observe the results.  The doctor, in a seeming bid to increase the pressure on the eyeball but prevent it from popping out of its socket, fought the forward pressure the nurse applied with pressure against the surface of the eye with the monocle. This was excruciating.  

The doctor seemed resigned to it after five or ten minutes of wrestling (I call it that, although I don't think I moved a single millimeter the entire time), and began his attempts at the laser cut. This, as I was told prior to the procedure, should have been 4-5 quick zaps with the laser in each eye, some minor discomfort, and done. After 15 minutes and about 35 zaps on the first eye, each of wish increased my discomfort along an exponential curve from "Shit!" to "Fuck!" to "FUCK YOU!", I was done.  With the first eye.  I was thankful, and at least prepared, I thought, for what was to come.

The second eye was much more difficult.  I lost count after 60 laser shots, and I'm sure I scared at least 3 potential customers out of the waiting room with my cursing the doctor, his nurse, and the lack of vallium or more potent sedatives, my bulging eye, and anything else I could seize on and malign for its existence.  The nurse was appropriately horrified by the whole thing, and said later that she'd never seen anyone take that many shots to complete.  Nevertheless, the doctor did eventually call it quits.  Between eyes, the doctor had announced that I had the thickest corneas he'd ever seen, and that this was preventing the laser from creating the size opening they needed.  That, and not being able to get my head in the proper position.  From that point, I had to reschedule another procedure that Friday, to enlarge the opening in the left eye the doctor had managed to create.

Recovery from the first procedure was about 6-8 hours, for me, before what was soreness subsided to a dull ache.  The next day, I returned to work with slightly reddened, irritated eyes that lasted the working day.

Friday's appointment went much better.  It had occurred to me since the first procedure that a slight tilt of the head to the side and perhaps being allowed to come out of the chin rest a bit would have given the doctor the better angle needed to do the job. This was confirmed on the second visit, when the nurse asked me to do the same prior to me suggesting it.  Once allowed to re-situate my head a bit, the procedure went off just as expected:  Five shots and done, with only mild discomfort.  They had offered me a mild dose of Valium for that portion of the procedure, however.  I took it.  It's not a painkiller, but there was less cursing and I exhibited what you would call a sunny disposition as I left.  I was informed that that was the way things were supposed to have gone on the previous visit, and I remember thinking how alike Friday's visit was to what they described on Tuesday.

The following Monday, I came in for the last procedure:  The insertion of the lenses.  The regimen of numbing and dilating drops I was given was much more elaborate, and I was offered, and given, the strongest dose of Valium they could safely give me prior to the procedure.  After an hour or so of observation of my eyes' compliance with the drugs, I was escorted to the operating room and allowed to lie back in a long, dentist-style chair.  My right eye was first covered with adhesive paper cloth sheet that extended over my face, then exposed by virtue of a tear-away, eye-socket-shaped cutout that was removed to allow the procedure.  During the procedure, the incision was made at the side of the iris opposite the opening made the previous week, the folded lens was inserted into its proper place, and various squeezing and manipulation was done to the eye to situate it.  There was a level of discomfort; I'd liken it to that one experiences with a drill-and-fill dental procedure, but it was nothing to be worried about.

By far the most disconcerting part of the procedure was during the insertion.  You are asked to fix your eye on a point throughout the procedure, but even as your eye is fixed, the images you see swim and convolve like paint behind a stir stick...often, what you are focused on, without moving your eye at all, moves completely out of your field of view.  The only things you see with any clarity, really, are the (often sharp) instruments coming into proximity of your eyeball.  You feel a stinging on the side of the insertion, and you can feel the insertion itself and manipulation of the eyeball by the doctor (I think he squeezes fluid around the lens once it's inserted), but these are dull aches, and not overly discomforting. At random intervals throughout the procedure, the nurse is asked to irrigate the eye, which actually feels cool and refreshing.

The procedure takes about a half hour each eye, but the vast majority of this is the doctor folding the lens and otherwise fiddling with equipment.  The actual insertion process takes place over the course of five minutes for each eye.  Once the first eye is completed, there is a lull prior to the second beginning, as the doctor observes the proper fitment and disposition of the lens in the eye. It is at that point that most notice a change in the way things focus for that eye, although the ability to bring things into sharp focus is diminished through most of the first day.

My procedure lasted from noon until about 2:30 p.m., and although I noticed the change in visual acuity during the car ride home, I didn't get the full effect until about 9 p.m. that night. This morning, the day following the procedure, I had my follow-up visit with the doctors.  I easily read the 20/15 line on the eye chart, and I'd describe my eyes as comfortably working the way a non-myopic person would expect them to work.  Occasionally, I have dryness to the right eye, and some sensation of "something in the eye", but to describe it as discomfort would perhaps be too much.  This is expected to subside over the coming week.  I'm required to wear some guards on my eyes as I sleep for the next two weeks, but these have no arms and are actually more comfortable than the glasses I used to wear. I also have a required regimen of drops to keep to, every four waking hours during the next two weeks.  After that, I expect smooth sailing.

Would I do it again, or recommend it to a friend?  Yup.  Walking around with better-than-20/20 vision is a beautiful thing, and even my atypical experience with the YAG was worth it.    


1 comment:

  1. Finally, the careful, often muted color tones delivered by Dave Stewart are perfect for this story. There were one or two instances where I wished I was seeing more widely ranged use of color, but I'd hesitate to recommend him anything in that regard lest the story suffer for more detail than is necessary. The eye is drawn to the right places, and the color composition all lends to story flow, and, well, it's just wonderful.more information