Monday 6 June 2022

Cataract surgery

About 2 1/2-3 years ago I was having a lot of trouble with glare and started wearing polarising sun glasses whenever the sun was low.  Then last August I was due an eye checkup, but I put it off a week as we were going on holiday.  A few days into our holiday New Zealand went into Level 4 lockdown and the optometrists shut.  By November, my eyes were really weird.  I had transient blind spots; I was perpetually cleaning my glasses as it felt like they were dirty; I was seeing shimmery arcs from time to time.  In early December, optometrists were allowed to re-open and I showed up on day 3 :-)  To my considerable surprise, I was told I had early-onset fast-growing cataracts in both eyes.  Both my parents have had cataracts so it seemed likely I'd get them one day, but I wasn't expecting them at 45!

 My GP referred me to an eye specialist, who said that my cataracts were already bad enough to qualify for surgery with our health insurance.  By that stage (mid-January) I was having more and more trouble - including seeing shimmery geometric grids of dots when looking at white surfaces on a bright day.  He thought I should have them done fairly quickly, but I put them off for a bit - partly because of various commitments, partly because I learned I wouldn't be able to swim for three weeks after.  I love swimming and thought my eyes were manageable, so decided to wait till winter when the tides are such that my local beach is often unswimmable for 3-4 weeks at a stretch anyway :-)

My eyes then proceeded to get rapidly worse, and I more and more felt like I just couldn't see properly.  My brain was also clearly compensating more and more for the vision loss.  At least twice whilst swimming, I was carefully avoiding someone else in the water as I swam a considerable distance, only for them to eventually disappear.  Presumably they were never there in the first place!  Sometimes my brain just gave up, and the image I was seeing was presented to me 'unprocessed' with great big holes in it.  That happened when we were biking to the ferry from the campsite in Waiheke in April and I was battling asthma, and again a few weeks back when I was watching a long movie and my brain suddenly 'gave up'.  That time. the image I was seeing switched abruptly from 'normal' to 'full of holes'.  I could no longer see any definition of anything with a bright light behind it - people standing in open doorways were just silhouettes.  I stopped riding my bike at dusk or at night - at dusk it felt too hard to be confident where cars were on the road; at night car headlights had huge halos around them that obscured the entire road.  I struggled with text against a low-contrast background, as well as small text.

So I decided to try and book the surgery a bit earlier than I'd originally thought, and ended up with the first surgery Thursday 12 days ago and the second Monday a week ago.

Just home from the first surgery

I've been very wiped out by the surgeries, although I'm steadily getting better.  The difference in my vision is striking.  I hadn't realised how blurry everything was - everything is so much sharper now, and colours are bright.  I've also discovered a remarkable number of fine cobwebs around the house ;-)  But the thing that's been most amazing has been realising how what I see isn't really what my eyes take in - it's an image construction from that, presented to my self by my brain.

I don't usually think of my self as separate from my brain, and I don't think it's ever been made so clear to me how different the two are.

I've now got two fairly differently focusing eyes.  In the hope of never wearing glasses again, my left eye now focuses maybe 30-ish cm out and my right eye focuses for 'distance' (which puts anything from about a metre away in clear focus)

I've spent a lot of time this past week covering one eye and then the other, to work out which eye I'm 'seeing' through.  My brain is seamlessly picking one or the other, whichever is most suitable, without any input from 'me'.

I was warned this might not work so well at night.  I haven't been well enough to go out at night since the surgery, but Martin and I are currently eating all our meals outside.  The other night whilst waiting to start dinner, I was looking at the crescent moon.  It was moderately clear, but had a blurry shadow.  I thought that was odd, and tried looking at it with one eye then the other.  My 'reading' eye gave a really blurry image, my 'distance' eye was sharp, and the two eyes together were giving an image that was a bit of both.  After checking that a few times, I suddenly realised the two eyes together were no longer giving a blurry image: when I had both eyes uncovered, I now only saw the sharp image from my 'distance' eye.  'I' had just trained my brain as to which eye to pick in this scenario!

I'm still having some odd depth-of-field experiences - things that I know are distant from each other are being presented to me as close together.  Presumably my brain will figure that out over time.  I initially had positive dysphotopsia in my 'distance' eye (which manifested itself as long streaky lines coming out from either side of street lights and headlights).  That will likely settle, although I have no idea if it has yet or not: I haven't been out far enough at night to encounter streetlights or headlights.  It seems to be a brain processing issue, and settles best if you don't pay attention to the lines.  And my 'reading' eye had a flickering shadow to the side of my vision, which may have been negative dsyphotopsia, or maybe minor corneal damage from the surgery, or both.  That seems to be settling, although it hasn't yet gone away completely.

Lots of eye drops!  Two boxes to make it easy to use different ones for each eye, and hand sanitiser to use beforehand and between eyes - they're big on not spreading potential infection.

I'm so grateful to have been able to have the surgery.  It's been an immense amount of fuss: lots of measurements taken beforehand (using maybe 4-5 different high-tech machines), decisions to make about the kinds of lenses I wanted, oodles of eye drops immediately before surgery, three kinds of eye drops three times a day for a week after surgery (tailing off over the following two weeks)...  And yet, while I was reading up about dysphotopsia I came across a startling statistic.  At least as of 2007, more than 25% of cataract surgeries done in majority world settings result in vision worse than 6:60 after 6 weeks (a "poor outcome").  My reading eye doesn't seem to have quite 'settled' yet (one week post-op this is, apparently, not unusual), and is still a bit blurry, but my 'distance' eye already had perfect 6:6 vision 4 days after the surgery.  No one was terribly surprised.  All that expensive and time-consuming 'fuss' is presumably what makes the difference, and means that such 'poor outcomes' are vanishingly rare here.  I'm grateful I was able to have the surgery at all, as my vision was getting worse pretty fast, but I'm especially grateful I was able to have the high-fuss, high quality outcome version, too!

1 comment:

  1. I love your description of discovering that yourself is separate from your brain and that what your eye takes in is different to what you see.

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