October 2020

IN FOCUS

My Worst Complication
Managing cases of corneal wound burn


by Liz Hillman Editorial Co-Director


Kevin Miller, MD, shared this image of a mild phaco burn from one of his cases. Note the fish-mouthed external incision. The cornea is scarred. The 10-0 nylon suture has been removed.

This is a fresh wound burn produced by someone else that Dr. Miller sent to EyeWorld. It took three sutures to close the incision.

This is a mild, older wound burn that was referred to Dr. Miller. Notice the corneal scar. It will persist indefinitely, he said.

This is a severe wound burn produced by a former fellow of Dr. Miller. It took five sutures to close this <3 mm incision.
Source (all): Kevin Miller, MD


Kevin Miller, MD, conducted an experiment to study the thermal effects of phaco. The silicone test chambers capping each phaco probe simulate the cornea. The rubber bands simulate compression by the corneal incision. An infrared thermal camera (not shown) measures the heat produced at the “incisions” after ultrasound is activated.

This image by an FLIR camera shows the heat generated by the three probes. The highest temperate in degrees Celsius within each of the three circles is displayed to the right. Any temperature above 50 degrees Celsius is capable of producing a corneal burn.
Source (all): Kevin Miller, MD

Thanks to improvements in phaco technology and ophthalmic viscoelastic devices (OVD), wound burn in cataract surgery is a rare complication. But when it does happen, it can compromise a patient’s quality of vision, often inducing astigmatism. Lisa Nijm, MD, JD, and Audrey Talley Rostov, MD, shared their experience with wound burn.

‘It was a good early lesson’

“I had read about wound burn and knew of its potential, but with newer technology and with viscoelastic, it’s pretty uncommon. However, there is a greater likelihood with more dense nuclei and when there isn’t as much fluid movement in the chamber,” Dr. Nijm said.
The case Dr. Nijm handled several years ago had both risk factors present. Her patient was an 86-year-old female who had a 4+ nuclear sclerotic cataract with 3+ cortical changes and a 3+ posterior subcapsular cataract. Her vision was count fingers before surgery.
“While I was removing the nucleus with phaco, there was a point that I think a portion of very dense cataract became occluded in the tubing, and I noticed there was whitening at the wound. I knew this was problematic and I immediately stopped,” Dr. Nijm said. “I also had been using additional viscoelastic to try and protect the corneal endothelium from the increased ultrasound power, but in doing so, I may have inadvertently reduced fluid movement as well.”
Dr. Nijm said there is a careful balance between creating a pocket under the viscoelastic when removing the nucleus and keeping the viscoelastic up against the cornea for endothelial protection, while not restricting fluid movement in the eye.
“As soon as I noticed whitening, I stopped, removed the phaco handpiece, and tested it for occlusion. At that point, I ensured an adequate pocket was present to allow fluid egress and carefully removed the remainder of the cataract with as little energy as possible,” Dr. Nijm continued.
She said the wound was leaky from the minor burn and required three sutures at the end to close. The patient had 2 D of astigmatism postop, which was much less than expected. Dr. Nijm said there is usually more astigmatism to start, and over time (several months), it tends to dissipate.
“It was a good lesson for me early on and is something to always be aware of,” Dr. Nijm said.
Dr. Nijm offered the following pearls to avoid instances of wound burn:
• Understand the importance of fluid movement to allow the egress of fluid and the cornea to cool. There is heat generated at the ultrasound tip, and if there isn’t enough fluid movement, it can cause a burn.
• Pre-chop as much as possible when you have a dense nucleus. miLOOP (Carl Zeiss Meditec) can be helpful to accomplish that in cases of mature cataract.
• Create a precise incision and look for signs early on (such as a white, smoky appearance in the anterior chamber as you phaco).
• Once whitening at the wound occurs, a corneal burn has already taken place. Therefore, it is important if you see any potential signs to immediately stop, remove the phaco tip, check for an occlusion, ensure fluid is properly moving in the eye, and carefully proceed forward.

‘I switched to bimanual phaco for better fluidics’

Dr. Talley Rostov had one case of wound burn in her career, more than a decade ago.
“Healon 5 [Johnson & Johnson Vision] had recently come out, and I had heard it was useful for maintaining the chamber in complex cases. I had a patient with a dense cataract and IFIS. I didn’t realize just how well the Healon 5 maintained the chamber and did not allow circulation of fluid. This was also with older phaco technology,” Dr. Talley Rostov explained.
The wound burn that resulted from this combination was difficult to close, requiring sutures and glue. The patient had significant astigmatism, even after sutures were removed, Dr. Talley Rostov said. Fortunately, it was correctable with glasses.
Since then, Dr. Talley Rostov said she switched to bimanual phaco for better fluidics.
“Bimanual phaco allows for separate irrigation and better fluidics,” she said.
She also became more careful with her choice of OVD and more aware of the potential for wound burns with prolonged phaco, as well as the potential for occlusion of the phaco handpiece and how to avoid that.

At a glance

• Corneal wound burn during phacoemulsification can happen quickly.
• It’s often associated with denser cataracts and occurs due to friction, not enough fluid movement, and phaco tip occlusion.
• Phaco wound burns can induce astigmatism.

About the doctors

Lisa Nijm, MD, JD
Founder and Medical Director
Warrenville EyeCare & LASIK
Warrenville, Illinois

Audrey Talley Rostov, MD
Partner
Northwest Eye Surgeons
Seattle, Washington


Relevant disclosures

Nijm
: Carl Zeiss Meditec
Talley Rostov: None

Contact

Nijm: lmnijm@uic.edu
Talley Rostov: atalleyrostov@nweyes.com

Corneal wound burn cases with Sumit “Sam” Garg, MD

At the 2019 ASCRS Annual Meeting, Sumit “Sam” Garg, MD, Medical Director, Gavin Herbert Eye Institute, Irvine, California, described a couple of cases of wound burn and shared how he handled them. One occurred in a 55-year-old male with brittle diabetes and a dense, hand motion-only cataract. Dr. Garg used a 2.75-mm incision, a Malyugin ring at the start of the case, and Healon EndoCoat (Johnson & Johnson Vision) as his OVD.
When the burn occurred, Dr. Garg said he kept operating through the same incision, citing that phaco burns are not likely to happen again in the same place. After the cataract was successfully removed, Dr. Garg asked the panel how to manage the incision/burn site.
“I think you need sutures. I’m a big fan in a case like this, or in any case where the wound is gaping, to have a mattress suture because I think it provides closure in two different vectors. I put that in before I get my viscoelastic out so I maintain the chamber,” he said.
With cyanoacrylate glue and more sutures Dr. Garg said he was able to get the wound closed.
Dr. Garg also described a case at the 2019 ASCRS Annual Meeting that was referred to him that already had wound burn and a persistent wound leak.
“In this case I had to repair it,” he said.
Dr. Garg showed how he made a partial punch using a 3.0 mm skin punch, allowing him to remove the unhealthy tissue. Dr. Garg then made a patch graft with a healthy corneal graft.
“The pearl here is when you place your stitches, you can see the middle stitch I’m trying to make shorter to make sure it does not encroach on the visual axis,” he said.
Dr. Garg said this improved the patient’s vision and closed the wound.

Relevant disclosures

Garg: Johnson & Johnson Vision

Contact

Garg
: gargs@uci.edu

Managing cases of corneal wound burn Managing cases of corneal wound burn
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