The LASIK Plume

Where There's Smoke . . .
Ophthalmology Management
April 2001

Eliminating LASIK laser plume may have a host of beneficial effects -- including improving your outcomes.
By Christopher Kent, Senior Associate

Excerpts:

As you may know, the excimer laser was first designed as an industrial laser used to etch computer chips. But the technicians who used the laser for this purpose discovered a problem: The laser didn't etch the chips correctly because the plume of smoke rising from the chip interfered with the laser beam. So, they went to great lengths to design vacuum systems to remove the smoke as rapidly as possible. With the smoke out of the way, they were able to etch the chips exactly as intended.

If you sit next to most patients undergoing LASIK, you can see sparkles in the air above the eye during the ablation. This is caused by the laser beam striking particles in the cloud of laser plume being produced by the ablation. It's the exact same problem encountered at the chip factory -- only in this case, it's someone's vision that's at stake.

Removal of the "burning flesh" odor is not only more pleasant for the patient, but can save you embarrassment. "Ninety-nine out of 100 patients don't smell the plume when I use the Mastel system," says Dr. Dudley. "After telling them this is a 'cold laser,' this saves me from having to explain why a cold laser makes a burning smell.

Exploring excimer laser plume dangers
EyeWorld June 2001
Lisa B. Samalonis

Excerpts:

In ophthalmology, when the excimer laser strikes the cornea, a thin layer of corneal cells is released. These cells create a plume of tissue that scatters into the air seconds after the laser strikes. The plume consists of carbonized tissue, blood, and the gases benzene, toluene, and formaldehyde, and polycyclic aromatic hydrocarbons.

In another case reported in 1998 in EyeWorld, Jerald L. Tennant, MD, a refractive surgeon from Texas, was forced to retire due to health problems he believes may have been caused by airborne corneal particles or viruses contained in the plume generated from the laser. Tennant, developed idiopathic thrombocytopenic purpura (ITP), a rare condition in non HIV-positive adults, in which the body's immune system produces antibodies that attack and destroy platelets. Another ophthalmologist, who prefers to remain anonymous, also developed ITP since beginning to use the excimer laser in 1990. "The incidence of ITP in the general public is rare," Tennant said. "To have two excimer laser surgeons develop ITP after the same amount of exposure is suspicious. That is why I have recommended that excimer surgeons follow their platelet count until the issue is resolved."

"Most ophthalmologists know a LASIK surgeon with laser lungs," she said, adding that many surgeons have asthma and experience the loss of their voices.

"My staff is very concerned about it; they know LASIK technicians with chronic coughs," she added.

Dealing with surgical smoke
EyeWorld February 2001
Lisa B.Samalonis

Excerpts:

During the surgery, when a laser or electrosurgical unit is used, thermal destruction of tissue creates a smoke byproduct (plume). In ophthalmology, when the excimer laser strikes the cornea, a thin layer of corneal cells is released. These cells create a plume of tissue that scatters into the air seconds after the laser strikes.

Another concern is that the laser plume may transport infectious diseases or viruses, such as HIV-AIDS or hepatitis. He said that it might take years to definitively determine if the laser plume is dangerous to the surgical staff. However, the dangers of breathing plume smoke from CO2 lasers are documented in dermatology literature. "The typical particle size in the plume of an excimer laser is on the order of 120 nm, which is in the general range of coal dust and several compounds in cigarette smoke. It is conceivable that the plume might also contain prions, and the consequences of breathing this material are totally unknown," Dell said.