Thinking on my feet, by Dr Leigh Spielberg
Sometimes the best outcome follows from a ‘Plan B’ and helpful advice from a senior colleague
I hadn’t seen the patient in several weeks, so I was in for a bit of a surprise when I first looked through the operating microscope. Behind the large nasal pterygium and unusual anterior stromal scar, the iris was stuck to the endothelium for nearly 360° in the mid-periphery.
The anterior chamber was more of an idea than a reality. And yet the globe was soft, unpleasantly so for an eye that was about to undergo lens extraction.
‘Lens extraction’, rather than ‘phacoemulsification’, had been indicated on the patient’s surgical planning document, which suggested how my vitreoretinal colleague, Fanny Nerinckx, expected the procedure might progress.
The pupil size was noted as ‘1mm, no motion’. Lens density: ‘no evaluation possible due to inflammatory membranes and neovascularisation, active’. Oh boy.
Although I hadn’t seen the patient, I knew his file well. He was a forty-something male who had undergone brachtherapy and transpupillary thermotherapy for a parapapillary choroidal melanoma. He had been referred to Dr Nerinckx for cataract extraction and reconstitution of the anterior chamber, so that the posterior segment could be followed up more closely than with ultrasound alone.
“Press record, will you?” I said to no one in particular. I figured this would make for interesting video footage.
The temporal paracentesis started with a challenge: how to enter a soft eye with no anterior chamber and a neovascularised iris adhering to the cornea? I made a tiny limbal incision and tried to instill phenylephrine, but it encountered iris resistance and came right back out.
On to Plan B: slow injection of OVD. The iris dehesced remarkably easily, thankfully. It was a sort of viscodissection. OK, I thought, one step down, a few dozen to go.
Haemorrhage! A little vessel on the iris was unhappy with my manoeuvre. The bleeding was contained by the OVD, but threatened to turn into a sticky mess soon if I didn’t come up with a solution. OVD out, phenyl in, OVD back in – problem solved.
OK, and now for the pupil. A 27G needle works perfectly to create watertight limbal ports for iris hooks. In they went. The cohesive OVD was doing a good job of maintaining the anterior chamber, but the iris hooks couldn’t latch on to the pupillary edge due to the membrane.
Dr Nerinckx, who offered useful advice throughout the procedure, suggested I try to think more like a vitreoretinal surgeon. In went my ILM micro-forceps, via the nasal paracentesis, which I used to elevate the iris so that the micro-scissors, inserted temporally, could pierce the membrane and I could explore the pupillary space. But the scissors couldn’t penetrate. Complete calcification. In went a second pair of ILM forceps and out came several chunks of hard white calcium. What had I gotten myself into?!
Once the pupil had been opened, the iris hooks had something to hold onto. I now had a nice square pupil, 5mm across. But deciphering the white mess that filled the area in front of the lens was the next step. It was fluffy like fibrin, stringy like vitreous, and as difficult to grab as smoke. The micro-forceps were now useless. Maybe irrigation/aspiration? No. “Think like a VR surgeon,” I heard Dr Nerinckx say.
Time for the vitrectome. I hadn’t planned to use it this early in the procedure – I was half expecting to have to use it to clean up a dropped nucleus – but it was my only option to allow identification of the capsule for a capsulorhexis. It worked like a charm, but the irregular surface it left behind didn’t really play nicely with the Vision Blue I injected next.
This is where I encountered the most difficult situation of the procedure. I still couldn’t properly identify the anterior surface of the lens capsule. The very unusual combination of inflammation, calcification and neovascularisation had left behind a bizarre moonscape of irregularities on the anterior lens face, and Vision Blue simply resulted in a splotchy mess. A capsulorhexis can be tricky under the best of circumstances, but this was anything but ideal.
I made no useful progress with the cystotome, the rhexis forceps and the ILM forceps, so in went the vitrectome once again. This was a new step for me. I’ve opened many a posterior capsule with a vitrectome. If done correctly, these prove to be circular and stable. In this case, the capsule was indistinguishable from the rest of the tissue present, so I had to trust my instincts and perform a motion similar to that of a posterior capsule. Round and round I went.
And yet, I didn’t trust it completely. But there was clearly no turning back now. In went the phaco tip. I didn’t dare try to chop, considering the invisibility of the rhexis border, so I started sculpting, lightly at first. Chatter chatter chatter! Hopeless. I increased the phaco power. Four miraculously smooth sculpts and cracks later, the quadrants were removed with the capsule intact.
Amazing! We had done it!
“OK, please stop the video recorder,” I asked a nurse.
“Sorry? You never asked us to turn it on!”
Dr Leigh Spielberg is a vitreoretinal and cataract surgeon at Ghent University Hospital in Belgium