The Laser Probe, The iKnife and The Cutting Edge of Surgery

08/31/2016 05:29 pm ET Updated Sep 01, 2017

If the thought of going under the knife fills you with fear, be reassured.

No longer is surgery the brutal and hazardous experience faced by our ancestors.

Thanks to wonders such as laparoscopy, robotic solutions, and, more recently, the iKnife and the laser probe, surgical intervention is getting safer all the time.

Archaeologists believe that people have been carrying out surgery for up to 11,000 years. Cranial surgery, known as trephination, probably dates back to the Neolithic era. It involved drilling a hole in the skull of a living person.

Speculation suggests it was done to cure disorders such as convulsions, fractures, headaches, and infections. The Ancient Egyptians used the same operation for "letting out" headaches and migraine.

From 1812 onward, the New England Journal of Medicine offers accounts of procedures that would now be considered gruesome, such as passing a hook through a man's pupil during the removal of a cataract, and using leeches for bloodletting.

Pioneers of their time, both surgeons and patients displayed remarkable courage.

Leap from there to the present, and you have minimally invasive surgery where even a heart transplant is now relatively routine. From January 1988 to July 2016, 64,055 cardiac transplants have taken place in the United States, according to the United Network for Organ Sharing (UNOS).

Advances in minimally invasive surgery

In 1987, a French gynecologist performed the first recognized laparoscopic surgery to remove a gallbladder. From there, the practice has expanded rapidly. According to the U.S. Food and Drug Administration (FDA), more than 2 million laparoscopic surgeries are carried out each year in the U.S.

In laparoscopic or "keyhole" surgery, a small tube with a light source and a camera passes through the body until it reaches the relevant part. The areas that need operating show up on a screen, while the surgeon works the tools through small openings.

Minimally invasive procedures mean smaller incisions with less scarring, a lower risk of infection, shorter hospital stays, and reduced convalescence.

Robotic surgery

Next stop, robotic surgery. In 2000, a team of scientists in Germany who were researching techniques for minimally invasive surgery announced that they had developed a system with two robotic arms that are controlled by a surgeon at a control console. They called it ARTEMIS.

In July 2000, the da Vinci system was approved for use in the U.S. for cutting and surgery.

It was the first robotic surgical system to get FDA approval, and its use has become relatively widespread.

The system has three components: a vision cart with a light source and cameras, a master console where the operating surgeon sits, and a moveable cart with two instrument arms and the camera arm.

The camera provides a true 3-D image that is displayed above the surgeon's hands, so the tips of the instruments seem like an extension of the control grips. Foot pedals control electrocautery, camera focus, instrument and camera arm clutches, and master control grips that drive the servant robotic arms at the patient's side.

There have been reports of errors and malfunctions, some of them fatal, and not everyone is convinced that robotic surgery really produces better patient outcomes.

What the eye cannot see

The electrosurgical knife was invented in the 1920s. Using an electrical current, it rapidly heats the body tissue, enabling the surgeon to cut through the tissue with minimal blood loss. It is commonly used in cancer surgery.

Image-driven surgery, such as laparoscopy, has reduced the extent of intervention for many operations.

However, when it comes to cancer, images can show where the tumor is, but neither images nor the human eye can readily distinguish between healthy and unhealthy tissues.

Dr. Zoltan Takats, of Imperial College London in the United Kingdom, saw a way for the electrosurgical knife to fill the gap that images cannot.

Enter the iKnife. Based on electrosurgery, the iKnife can detect precisely which tissue needs removing, and which should stay.

Until recently, the only definitive way to know whether tissue is cancerous or not has been to take a biopsy for study, usually under a microscope. The disadvantage is that during surgery, only very few samples can be taken and tested, and it can take 40 minutes to complete each test. This is not a practical way to define the edge of a tumor during surgery.

2013 saw the emergence of the first iKnife, which enables the surgeon to examine biological tissue by pairing up electrosurgery with mass spectrometry. In mass spectrometry, ionized, or charged, particles are passed through electric or magnetic fields.

Mass spectrometry provides measurements of mass-to-charge ratio, and these measurements make it possible to distinguish between tissues of different composition, known as chemical profiling. By analyzing the chemical composition of different samples, it can reveal which tissues are healthy and which are not.

At that time, Dr. Takats told Medical News Today that he expected the iKnife to be applicable to different kinds of surgery and that it would save costs.

How the iKnife works

Cutting with an electroscalpel causes the tissue to vaporize as it is being cut. This creates a smoke that is normally sucked away by extraction systems. But by connecting the iKnife to a mass spectrometer and pumping the smoke toward it, the vapor can be "captured" and analyzed for chemical composition. By matching the results to a reference library, the surgeon can see which type of tissue it is within 3 seconds.

In 2013, Dr. Takats and his team used the iKnife to analyze tissue samples collected from 302 patients who had undergone surgery to remove various kinds of tumor, both cancerous and noncancerous.

They recorded the characteristics of thousands of tissue samples taken from tumors in the brain, lung, breast, stomach, colon, and liver. From these samples, they created a database of 1,624 cancerous and 1,309 noncancerous entries, to which future samples could be matched.

The team then used the iKnife with rapid evaporative ionization mass spectrometry (REIMS) in 81 surgical interventions. Readings were taken during surgery, and tissue was tested afterward in the conventional manner. In each case, the reading matched the postoperative histological diagnosis exactly.

The iKnife was developed for electrosurgery because surgeons saw its potential for removing cancerous tumors, but its applicability to hydro and laser surgery have already been raised. In the future, it could be used to take readings to analyze mucous membranes and the respiratory, urinogenital, or gastrointestinal systems.

The iKnife is already in use at Imperial College London, and it is now being trialed in breast, colon, and ovarian cancer surgery.

Laser detection of brain tumors

More recently, researchers in the United Kingdom and Canada have paired up the iKnife with a laser probe to detect abnormal tissue during surgery to remove a brain tumor.

This technique used a near-infrared laser probe to determine whether tissue was cancerous or healthy by measuring light reflected off the tissue.

When they pointed the beam of light onto the exposed brain, molecules in the cells began to vibrate. As they did so, fiber optics in the probe collected the scattered light that was bouncing off the tissue.

By measuring the frequency of the vibrations, the scientists were able to tell which tissue was healthy and which was not. As with the iKnife, analysis took just seconds.

In cancer surgery, the ability to detect the exact border of an area of malignant tissue can make the difference between life and death, and between having to repeat surgery or not.

Being able to remove the exact tissue not only ensures that the whole tumor is taken away, but it also reduces unnecessary tissue loss, leading to better outcomes for patients.

The researchers note that, particularly with brain tumors, the inability to see the boundary of a tumor, even with a surgical microscope, puts people at a higher risk of additional damage, such as the loss of speech. As technology advances, the risks of surgery gradually decline.

Written by Yvette Brazier