The use of laser light for some microsurgical procedures isn't new. What is new, however, is the use of handheld CO2 laser scalpels for the safe removal of life-threatening tumors with minimal blood loss and minimal retraction to the brain or spine (and associated nerves).

For example, Dr. Narayan Sundaresan, a NYC neurosurgeon, whose mother was shot in the head when he was a boy, recently operated on a patient with a metastatic brain tumor in her temporal lobe. He performed the surgery at Lenox Hill Hospital using a BeamPath CO2 laser by Cambridge, MA-based OmniGuide (omni-guide.com). The laser allows the surgeon to preserve tissue around the tumor. Further, because it provides a "no-touch" procedure, it is at times safer than using alternative techniques, such as radiosurgery systems like the CyberKnife (accuracy.com) and Gamma Knife (elekta.com) systems. Sundaresan reports that the patient has returned home without any complications and will be spending the holidays with her family.

What is most appealing about the CO2 laser scalpel technology from a surgeon’s perspective, says Sundaresan, "is that the light beam is highly focused and it is possible to deliver the laser through a small handheld device using a flexible tube."

Sundaresan says the laser scalpel technology allows him to perform, in addition to the removal of tumors, other procedures that he otherwise wouldn’t be able to perform, such as dense or fibrous meningioma, acoustic tumors, and small spinal tumors.

Tabletop sophistication: material is key
Sundaresan is one of approximately 3,800 surgeons currently using the BeamPath technology and the Lennox Hill procedure referred to earlier is one of the 36,000 BeamPath procedures performed since it was introduced in 2006.

The laser's operating wavelength is 10.6µm and is delivered through a hollow core flexible fiber. Since the absorption depth of CO2 laser energy is shallow, damage to underlying or surrounding tissue can be minimized.

The ability to bend CO2 laser energy through a flexible fiber enables beam delivery to many locations throughout the body while providing increased control through a handheld instrument. Until such a glass material was developed in the late 1990s by a team of MIT scientists, the application of laser light in surgical procedures was limited. To achieve the material breakthrough, semiconductors and insulators had to be layered at submicron accuracy within a hollow fiber, something that was never before achieved, according to a July 2009 Science Times article, which also reports that the MIT team established for the first time a solid-state, "omnidirectional" mirror inside a fiber. These breakthroughs led to the founding of OmniGuide.

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Not only is the BeamPath fiber flexible, the system itself is portable, weighing just 62 lb. The laser is 8-in. high × 19-in. wide and 16-in. deep. And the fiber dimension is 150cm long with an outside diameter of 0.55–1.21mm. The spot size (size of laser energy emitted from the fiber, much like the light from a flashlight) is 0.25-0.32mm. This means that if the surgeon shoots the laser once at the tissue, the surgeon will get a spot the size of just 0.25-0.32mm.

"The 'tabletop' design is much more compact than the refrigerator-sized ones of the past," says Sundaresan. "Most others have a cumbersome articulating arm with mirrors that easily get knocked out of alignment. That was the standard since the 70s until OmniGuide came around [with its BeamPath system]."

Looking ahead
CO2 laser surgery allows for a targeted and precise removal of disease tissue with a minimally invasive approach and without the associated toxicities or side effects of radiation, even when delivered by precision radiosurgery systems.

"The side effects of radiation to the brain are well documented," says OmniGuide ENT & Neurosurgery Product Manager Leigh Drori. "However, radiation treatments remain an important option for those with difficult disease states and who opt not to have surgery for a variety of reasons. The surgery vs. radiation conversations are happening more often as surgical tools are getting better and cancer patients are getting younger (due in large part to earlier diagnoses) and must live with the side effects of radiation for longer."

As for the challenges involved in using the BeamPath, Drori says it comes down to training and awareness. "Many years ago, CO2 lasers were once part of the neurosurgeon armamentarium, but fell out of favor due to the lack of precision delivery tools. The advent of the BeamPath system and precise handheld tools represents an overdue shift, of the CO2 laser, back into the neurosurgical operating suite. Therefore, most neurosurgeons, as opposed to say, otolaryngologists, are not familiar with CO2 laser energy and its effect on tissue or its utilization in practice."

"This means that when faced with a difficult case some surgeons are not even aware that they have these tools at their disposal, and in order to use them they must undergo training and education, which OmniGuide provides to surgeons and hospitals at no fee." Drori says that in addition to neurosurgical procedures, today’s applications include otology, laryngology, gynecology, head and neck, and in some cases when the use of a handheld laser is vexing, robotic surgery. Looking ahead, Drori predicts BeamPath systems will be used for gastroenterology, interventional pulmonology, urology, and ophthalmology.

System enhances visibility during breast procedures

An illuminated breast retractor system is welcome news for surgeons performing skin and nipple-sparing mastectomies, lumpectomies, sentinel node biopsies and reconstruction procedures. The illuminated breast retractor system by San Francisco-base Invuity (invuity.com), San Francisco, was introduced at last month’s American College of Surgeons' 97th Annual Clinical Congress in San Francisco. It integrates Invuity's Eigr (pronounced eye-gr) technology, which utilizes optical structures to control light output to a targeted operative space. By directing light from multiple angles and managing light across a broad output surface, Eigr virtually eliminates shadows, back reflection, glare and thermal effects such as overheating. The system is also ergonomically designed so surgeons have greater comfort and maneuverability.

According to the American Cancer Society, more than 2.5 million women in the United States are breast cancer survivors; many chose surgery to remove the cancer.

"As a breast cancer surgeon for more than 30 years, I have closely followed the advances in surgical techniques with respect to breast conservation surgery," says Stephen DeSantis, chief of surgery, Mission Hospital in Mission Viejo, CA. "Invuity's Eigr technology enables me to perform advanced breast procedures with greater visualization than any system I have yet seen or used. This is truly an enabling technology that will be greatly appreciated by dedicated breast surgeons and plastic surgeons."

"Invuity's Eigr breast retractor system is the result of close collaboration with breast cancer surgeons to understand their need to visualize structures better during less-invasive procedures," says Philip Sawyer, chief executive officer of Invuity. "As a result, Invuity provides critical tools to aid in these procedures."