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Striking back

Cancer strikes fear into the hearts of its victims but Rob Coppinger finds that lasers are now able to excise that enemy within, deep inside the human body

Few subjects are as personal as an individual’s health and quality of life, and lasers are steadily making inroads into this most safety conscious of activities, to cure ills and make living that much easier.

From removing tumours, to decreasing the spread of tumour cells through sealing lymph vessels, and preventing blood loss by sealing small blood vessels, lasers can aid in the cure of serious illnesses or be used for cosmetic procedures. Skin conditions, including the removal of warts, moles, tattoos, birthmarks, scars, and wrinkles, can be treated with lasers, some of which can be used at home.

What is not being done at home, but is becoming commonplace is vision correction using laser surgery. While this will end a person’s need for corrective lenses, lasers can also be used to treat serious eye conditions such as cataracts. Ever more accurate lasers are enabling a high level of precision for the successful removal of cataracts.

Since July, the University of Illinois Hospital & Health Sciences System has used a femtosecond laser to remove cataracts for selected patients. This laser system for cataract surgery, with an accuracy down to a few hundred-thousandths of an inch, allows eye surgeons to optimise and customise the incision and ensure the best possible outcome. Approved by the US government’s Food and Drug Administration for cataract surgery, the laser is used to fragment the clouded lens for its removal. A femtosecond laser’s extremely short burst of energy allows for the bladeless incision. Used in refractive surgery to create a thin flap in the eye’s lens, the Uaniversity’s LenSx system provides a live, real-time image of the eye that allows the surgeon to set the laser to the exact required depth and dimension for the bladeless incision, ‘to the micron,’ says Dr Jose de la Cruz, professor of ophthalmology and visual science at the University’s College of Medicine .

‘I can see exactly where I want to place my incisions, as well as the exact diameter and depth of the cataract, prior to cataract fragmentation,’ de la Cruz says. ‘Once the laser is set in position, I press the pedal, and the laser will divide the cataract into pieces in less than 20 seconds.’ The patient is then moved to an adjoining operating room, where de la Cruz removes the cataract and replaces it with an intraocular lens. The whole procedure can be done under local anaesthetic.

After surgery, there is a ‘very quick visual recovery,’ de la Cruz says. Most patients wear a clear eye patch for a day and are seeing well almost immediately. Follow-up appointments are scheduled for the first and third weeks following surgery.

However, this precision can also be applied inside the human body, with the help of robotics. Since 2010 the Columbia University Medical Center and New York Presbyterian Hospital has reported that lasers could be used to safely remove men’s cancerous prostate glands, whose removal typically results in long term sexual dysfunction for half of all patients. ‘The precision of movement available through robotic surgery is already helping reduce the risk of sexual side effects, and the early evidence is that CO2 lasers will help us be even more accurate especially when preserving the sensitive nerve areas necessary for sexual function and urinary continence,’ says Dr Ketan Badani, director of robotic urologic surgery at the medical centre.  It is these crucial nerves that can be damaged with normal surgical procedures.  The laser is used to dissect the soft tissue between the nerves and the prostate, freeing the nerves and preserving them.

‘Traditionally, we cut, clip or cauterise the tissue around the prostate nerves. However, these techniques can cause irreversible damage due to traction or heat injury,’ explains Badani. ‘The CO2 laser may reduce this risk because it is low-heat and doesn’t require much manipulation of the nerves.’

Columbia University Medical Center and New York Presbyterian Hospital found that with 10 patients the laser technology was easy to manipulate and very accurate. Patients experienced a return of urinary continence better than the norm, something the researchers found encouraging. The centre and hospital are now determining if the technology can improve outcomes with regard to the ability of men to sustain an erection, and its long-term ability to prevent cancer recurrence.

According to the World Health Organization and World Bank, prostate cancer is one of the common cancers and far more common in high income countries than developing ones. The Columbia University Medical Center’s research, published originally in a 2010 issue of the peer reviewed Journal of Endourology, was a pilot study to evaluate the CO2 laser for prostate cancer. The laser technology, known as BeamPath, which is a flexible, fibre-based delivery system, was provided by OmniGuide of Cambridge, Massachusetts. OmniGuide BeamPath’s CO2 laser fibres are cleared for use by the FDA across a variety of open, endoscopic and laparoscopic soft-tissue cutting applications, including urology.

Flexible, fibre-based delivery systems for lasers can also realise procedures for cancers that had previously been considered difficult to reach in the head or neck. ‘Robotic surgery has revolutionised the way we care for our patients,’ says Eric Genden, professor and chair of otolaryngology at the Mount Sinai School of Medicine. Genden’s patients have cancers of the tongue, swallowing tube, back of the throat, or thyroid gland. ‘This [robotic] approach has been very successful in our practice in terms of clinical outcomes, but also quality of life outcomes. Our patients are back to work and their routine in a matter of days, which also reduces health care costs for them and their employers.’

Traditionally difficult to remove, removing cancers of the tongue, swallowing tube, back of the throat, or thyroid gland usually involves an external incision, beginning at the lip or jaw and extending to the ear. This large cut allows access to the tumour but also requires 10-12 hours of surgery that requires the patient to stay in the hospital for two weeks. The side effects of this surgery are often debilitating, resulting in severe scarring and an inability to speak, eat, or drink, rendering people socially isolated. However, the robotic laser approach, with access through the mouth, means surgery that only lasts two hours and the patient is able to return home the next day and able to resume all normal activities in 10 days. Called transoral robotic surgery, or TORS, the surgeon sits at a console directly controlling a robotic arm. This arm extends a small surgical instrument through the patient’s mouth. Using a high powered 3D camera, the surgeon can see the interior better, giving them greater dexterity and surgical precision. Through the robot, a laser removes the tumour completely along with all margins to make sure all tumour tissue has been removed as well. Led by Dr Genden, the Mount Sinai team has performed nearly 150 TORS procedures.

Whether it is the structures of the eye or sensitive nerves controlling body functions, the laser is increasingly used by surgeons as a tool of precision, going where the knife can’t. The physical flexibility of the fibre laser and the camera capabilities of the endoscope can only continue to give surgeons a keyhole surgery tool that is second to none for the patient.