2010-04-29

My experience with laser vision correction (PRK)

Just got PRK laser vision correction

I decided to get Lasik/PRK after realizing that the amount I have spent on glasses over the years added up to the cost of a Lasik operation.  I also owned a Canon 5D Mark II digital camera -- an awesome light-capturing machine -- and I realized the camera was worth as much as a Lasik operation, but that when I was focused on taking photos of beautiful scenery I totally missed the moment.  It is much more important to see with my eyes than through a camera lens.  So I sold the camera to pay for my laser vision correction operation.

I decided to write up my experiences in some detail so others have more information in one place than I was able to find when I was investigating getting this operation.

What is PRK?

PRK is like Lasik but rather than cutting, separating and peeling back a flap on the front of the cornea and then ablating (removing tissue) underneath the flap as with normal Lasik, with PRK they brush off the 6-cell-thick layer off the front of the cornea and then directly laser the front of the corneal protein.  It's more painful and has a longer recovery time but is an older, often more trusted technique and has numerous advantages.

I chose PRK over flap-based Lasik for the following reasons:
  • There are fewer problems with dry eyes with PRK compared to Lasik in the 6 months to 1 year after the operation, because there is less nerve damage done with PRK (there is supposedly less nerve damage with PRK than with flap-based Lasik, though I don't know the details).
  • There is less chance of dislodging the flap later in life with PRK, because there is no flap -- with Lasik, the structural integrity of the cornea is never again quite what it was, and even running into a tree branch can sometimes dislodge it.  It's not super-common for this to happen but if it happens it can give you serious vision problems, so the cost of a problem is high.
  • There is less chance of infection with PRK (you can get an infection under the flap with Lasik, which is relatively rare but can be pretty bad).
  • They ablate/remove less of the cornea with PRK than with Lasik, so if you need a touchup later on, you have more corneal tissue to work with.  Touchup operations are free within 6 months with my provider.
  • UPDATE: @GlennHagele stated on Twitter (I read this after my operation): "The first 3 weeks you will wish you had Lasik and then every day thereafter you will be glad you had PRK. http://USAEyes.org "
The downsides to having any form of laser vision correction at all include:
  • At about age 44 you start to experience presbyopia -- the inability of the eye to focus outside of a limited range -- and by the early 50s this process of deterioration in focusing ability is pretty much complete.  Laser vision correction corrects your vision to see to infinity with the eye's focusing muscles completely relaxed, and you'll eventually need reading glasses to see up close.  I'm 34 though and although I don't need glasses when reading books, I wear them 100% of the time anyway, and I do need them already when using a computer screen.  The way I figure it, I'll get 10 good years of use out of my eyes without needing glasses for anything, and then I'll just need them when reading a computer screen again (which I already do) or a book.
    • The main downsides I see with presbyopia are that I will have to carry around reading glasses with my cellphone, otherwise I won't be able to read text on the cellphone screen (and that I won't be able to see my wife up close!)
  • Increased risk of chronic dry eye problems (I already had some issues with this, PRK/Lasik would make this worse, especially non-PRK Lasik)
  • Risk of haze / halos / starburst patterns around lights at night: your pupil is more dilated at night so the chance of having light refracted from both ablated and unablated regions of the cornea is higher, causing possible halos and other artifacts.  The chance of these side effects is higher with strong prescriptions, -8 diopters or worse.  My prescription is closer to -3 so I don't expect to have problems with this.
The downsides to PRK vs. Lasik
  • Recovery time (both in terms of pain and quality of vision) is much longer -- 2-6 weeks for PRK rather than 1 day for flap Lasik.
  • Important: you need to take Vitamin C and wear good sunglasses when outside for at least 6 months after the op, especially in the summertime (CONSIDER GETTING THE OPERATION IN THE LATE FALL) -- the new cells that regrow over the cornea are very susceptible to scarring in UV light.
One big upside of getting laser vision correction
  • I can finally wear REAL SUNGLASSES and still see!  Nobody that hasn't worn glasses for years could appreciate how great this is :-)  I bought polarized prescription sunglasses before and they can be really expensive.  First thing I did after the operation when I could get out and about again was to go look at sunglasses (since I'll need them anyway).

Consultations are usually FREE

Because some people are not good candidates for Lasik/PRK, most places that perform laser surgeries will give you a consultation (actually as many visits as necessary) for FREE before you get the actual surgery, to determine whether or not you're a good candidate.  You pay NOTHING until the day you get the surgery.  Personally I went in for about seven visits before my surgery because I had dry eye issues that needed to be treated with drops and monitored to make sure I could qualify for Lasik/PRK.  In the end it was determined I could get either, but PRK would give me fewer ongoing issues with dry eyes, so this was one determining factor.

Several things can make you a bad candidate for Lasik: overly-dry eyes, overly-wide pupils, overly-thin corneas, etc.  You should be aware that there are some cheap Lasik clinics out there that get as many people through as possible for ridiculously low prices.  Beware of clinics that don't reject people that are not good candidates for Laser vision correction!  This is your vision, don't mess with it.

Surgeon vs. fellow -- save 50% with a fellow-in-training

I elected to have the operation performed by a surgical fellow under the direct supervision of a surgeon with 20+ years of experience, rather than having an actual surgeon perform the operation.  Receiving surgery from a fellow reduced the cost of the surgery by 50%, from $6000 for both eyes to $3000 for both (and I further talked them down to $2800 for both).  A fellow has completed an MD, a residency, and was on a fellowship, one step away from becoming a full surgeon, and Lasik technology has become almost risk-free in the last three years, so I figured risk was minimal and cost savings were great.

I received the operation at Tufts New England Eye Center in Boston based on the fact that they provide free or heavily discounted treatment services to the disabled, first responders and the military (none of which I qualify for, but on principle).  They were very professional and knowledgeable, and did a great job.  Highly recommended.


The First Week of PRK

Note that as noted elsewhere in these notes, recovery time for standard Lasik mostly takes place within a day or so, whereas PRK recovery takes longer but is better for your eyes long-term so is worth all this discomfort and blurriness.

Day 0 -- Thurs -- PRK operation
  • Given 15mg of Valium which made me completely uninhibited and incessantly chatty -- I had the whole operating room laughing constantly :-)
  • You sit under the machine and see a ring-shaped light with a dull red glow in the middle, and a spotty interference pattern from another laser below.
  • Received anesthetic drops, then they taped my eyelids open and then put in a metal clamp to hold the lids open.
  • The surgical fellow used a small brush like a dentist's drill to brush away the cellular layer from the front of the cornea.  Painless but a weird sensation.  The lights swirled as the brush moved the eyeball in fast circular motions.
  • The surgical fellow then used a scraper to create a clean edge at the boundary of where the cells had been removed.  The bigshot surgeon checked through the scope a couple of times between scrapings and pointed out areas where the fellow had missed a couple of small spots with groups of cells.
  • They then started the actual laser surgery directly onto the cornea.  There were something like 239 laser pulses that ablated the surface in random order (to avoid overheating).  A camera looked for saccades (fast movements of the eye) with a frequency of something like 1000Hz and used a pre-stored image of the retina to register the ablation plan correctly to the eye (this is the Allegretto Wavefront laser way of doing registration) -- your eyeballs actually rotate a few degrees when you lie down, and it's almost impossible to stare at one spot for a period of time without eye saccades around even without you being aware of it.
  • The laser zapping process all seemed to happen in about 10 seconds.  Each laser pulse made a clicking/sizzling sound.  There was a vacuum tube by my eye but I could still smell burning protein.
  • They washed the surface of the eye with a lot of fluid then put in a contact lens, then repeated the whole process for the other eye.
  • Everything was pretty cloudy when I stood up but my vision seemed somewhat sharp.  The valium had kicked in with being horizontal for over half an hour, so I was pretty dizzy and needed help walking at first.
  • I had to get a ride home, they wouldn't let me even take a cab because of liability.  I went home, figured I could see relatively sharply in spite of the haze, and the valium had mostly worn off, so I stubbornly drove the 5 mins to the pharmacy to pick up my prescriptions for painkillers and eyedrops.  Took painkillers and slept off the rest of the day.
Day 1 -- Fri -- day after operation
  • I had been given eye guards to tape over my eyes at night.  I woke up without them on -- found one guard strewn across the bed and the other one nowhere in sight, I still haven't found it to this day so I had to get a replacement :]
  • When I woke up my eyes were sore but it wasn't too bad.  Eyesight was hazy all day, had to squint to do much, and had to scale up font size on computer to huge.
  • Had to visit the eye center for the day-after appointment.  Vision tested as 20/15 (better than 20/20) in one eye and about 20/20 in the other -- sharp but very hazy.
  • Ended up taking painkillers and resting, pretty unproductive day.
Day 2 -- Sat
  • Probably the worst day for pain.  Felt like someone had poked me in the eye for most of the day.  Wanted to avoid painkillers so I just endured it.  Vision still hazy but usable -- took care of some errands, was able to be out and about for most of the day being productive.
Day 3 -- Sun
  • Probably the worst day for vision.  Also extreme light sensitivity, couldn't get up for 2-3 hrs because I couldn't open my eyes, even with the blinds shut.   Apparently trauma to the cornea makes the iris muscles spasm in reaction to light, "like getting a charlie horse in your eye".
  • Vision very blurry, borderline dangerous to drive.  Avoided people I knew at Church because I knew I wouldn't be able to tell if they were looking at me or not from more than a foot or so away.
  • Looked like I was looking through a steamy window during daylight hours.
  • Took painkillers and slept off most of the afternoon.
  • Distinct-shaped halos around lights at night, the shape of the wavefront of cells regrowing in towards the middle of my cornea.
Day 4 -- Mon
  • Couldn't open eyes again for about 3 hours after waking up because of light sensitivity.
  • Very little pain left but couldn't be productive in front of a computer screen.
  • Vision good enough to bike in for a checkup in the afternoon, the doctor wanted to make sure I had no infection.
Day 5 -- Tues -- contacts removed
  • No real problem with light sensitivity this morning, could tell that cells were almost totally regrown because everything was pretty sharp right when I woke up.
  • Got contacts out in the afternoon. Cells had completely regrown over the cornea (with the characteristic ridge or pileup of cells in the middle that was still scattering light) and looked really good according to the surgeon.
  • Vision tested as pretty good, but not quite 20/20 before removing the lens, but was worse afterwards.  The newly exposed cornea surface was not as smooth as the contact lens surface, because there was a (normal) ridge/pileup of cells where the regrowth coming in from both sides joined in the middle.
  • Eyes were pretty uncomfortable after the lens came out, but only for about 10 minutes, as the new cells were exposed directly to the air and eyelids for the first time.
  • Tried getting computer work done after getting lenses out, but needed eyedrops for dryness every 10 minutes or less, eventually ran out of drops and had to go home.  Still had to scale up text font size to huge.  Squinting constantly to see better gave me a pretty bad headache.
Day 6 -- Wed
  • Eyes were really sensitive to light again after getting lenses out, had to spend whole morning in bed again.  Couldn't do much productive.  Vision was not bad early in the day but got worse.  Had to drive somewhere anyway.
  • Had moments of near-perfect vision after putting in drops -- amazing to see clearly again after everything being blurry for a week.  However things were still a little fuzzy.
  • The extra dryness experienced yesterday was mostly gone, was able to be relatively productive, only needed drops every 30 mins or so.
Day 7 -- Thurs
  • Woke up with very dry eyes almost stuck to eyelids.  Light sensitivity first thing in the morning only lasted for a few mins once I put drops in.
  • Vision was very clear the instant I put drops in but got fuzzy within a few minutes of each set of drops.
  • I can finally be productive on my computer again at normal font size, albeit with fuziness, but without squinting.
  • I have been informed I'm totally on-track for having perfect vision restored within 2-6 weeks of the operation, so it will in theory only get better from here.  Vision will usually be best in the morning and dry eye problems will be worse when working at a computer (which I do all day).
  • I expect the log will be boring from this point on so this will be the last entry :-)

Overall experience

This all sounds bad, but it's worth it if I never have to worry about wearing glasses again!

Post-op considerations
  • Important: Need to take Vitamin C and wear good sunglasses when outside for at least 6 months after the op to prevent scar tissue forming on the cornea.
  • You're given painkiller drops right after the operation but you're told not to use them after day 2 as they will slow down the healing process.
  • You have to wear eye shields to bed every night for 2 weeks.
  • No shampooing hair for 3 days to prevent infection; wearing swimming goggles for showering for 2 weeks after the operation, or at least have to wash hair/face outside of shower to keep water and soap out of eyes.
  • No eye makeup for 2 weeks for the ladies, no swimming for 3 weeks, only light exercise and no weightlifting for 3 days, sweatband should be worn during exercise for 2 weeks.
  • Antibiotic drops have to be used for a week or more, steroid drops for 3 weeks, preservative-free artificial tears every hour while awake (as much as every 10 minutes as needed).
  • Taking fish oil and flaxseed oil can alleviate dry eye problems.

Final thoughts


WORTH THE PAIN/BLURRINESS: Overall I can tell my vision is going to be great and I would recommend PRK due to reduced risk of complications with PRK, and because of the ability to get a touchup operation as needed.

LASIK HAS COME A LONG WAY: Lasik is far safer today than it was even three years ago, with fewer chances of side-effects.  I wasn't comfortable with getting it until recently.


THE BEST LUBRICANT EYE DROPS FOR SENSITIVE EYES
I have tried about eight different types of eye drops, and all of them but one have given me problems with increased redness and other sensitivity issues.  I now use Tears Naturale Free, they give my by far the fewest problems (my eyes react to many other types of lubricant drops).


CHEAP GLASSES FOR THE LASER-AVERSE: For those that are not ready to take the plunge to get laser vision correction, I recommend Zenni Optical -- prescription glasses for $8 (both lenses and frames)!  It's a company that operates out of Hong Kong but has an office in California, and brings Asian glasses prices to the US market (finally).

DONATE YOUR OLD GLASSES: One last comment, I learned the best thing to do with used glasses is to donate them, where they can be taken to clinics in the developing world.  Most eye clinics have a donation bin or you can easily find places online.

I donated four pairs of used glasses, and the realization that there were millions of kids in developing countries who are hindered in their learning and life progress simply because they can't see actually made me feel rather bad about getting PRK.  I had a "wow the gap between rich and poor is huge" moment when I realized these kids can't afford even basic glasses and yet I just had my cornea perfectly reshaped with a laser!!