what measurements should a surgeon take before a cataract operation?

[scheeler]

I've been having a bit of a distressing time since having IOLs placed in both my eyes (as explained in my recent post, 'huge shimmery structures after monofocal IOL implant - very worried'). It's caused me to do a lot of research on cataract surgery and IOLs, but there's one thing I haven't been able to find out from the Web: just how many measurements should a surgeon do before operating? And especially, should a surgeon measure your pupil size?

I'm particularly concerned about the latter because I keep wondering if my problem (huge halos around lights at night, bigger even than my field of view - like huge glowing dandelion clocks) might be due to my pupils being too large for my IOLs.

I should point out that I live in the UK, and I think it's the culture here not to ask medical people too many questions (it's a class thing, I think - 'Doctor Knows Best'). For this reason, though I chose the best surgeon I could, based on qualifications, number of operations, etc, when it came to the pre-op consultation, I found it hard to ask him many questions. All I could do was stress to him that, being a keen amateur astronomer, I wanted IOLs that were big enough to completely cover a dark-adapted pupil. To this he just said two things: (1) "IOLs can't be made too big, because then you run into various aberrations" and (2) "you don't have especially large pupils". But this was in his office, in daylight, and he hadn't measure my pupils with a pupilometer.

He only really did two things. First, he asked if I knew what my prescription was (odd that, I thought: I actually did know, but I imagine very few people would). And second, he measured my eyes with an instrument I had to look into, which had about 8 LEDs around its circumference. I've later read about something called a 'laser interferometer' - could that have been what it was? He then wrote a few things down, and that was that - 15 to 20mins max, I'd say.

At the time, I was happy just to rely on his judgment and reputation, but now things don't seem to be coming right, I'm beginning to wonder if all the necessary preliminaries had been carried out before my operations.

I'd be very grateful for any thought or opinions from people on this forum. Thanks.

[scheeler]

Thank you for that advice, Dr Hagan.

[John C Hagan III, MD, FACS, FAAO]

For standard cataract surgery the usual measurements are: 1. radius of curvature of the cornea, axial length of the eye with specific measurements of anterior chamber depth and lens diameter.

Pupil diameter is normally not measured in standard cataract surgery. In lasik type surgery or with multifocal/accommodating IOLs they area.

You might ask your surgeon to write a RX for alphagan P eye drops. They are for glaucoma but when used at night they prevent the pupil from dilating as wide as normal in the dark.

You can also get a second opinion.  Another test we sometimes done is corneal topography if we suspect keratoconus, there is corneal scarring, or previous corneal disease.

JCH MD