Manual to Robotic : Why surgeons are adopting robotic procedures?

By : Saurya Mishra

March, 28th 2023

One would often agree that we Humans are at the peak of evolution. The intellect of the human brain, the vision in the eyes, and the dexterity of the human hands and fingers are possibly unparalleled in nature. This allows humans to do things unheard of in the last million years of evolution.

One of these is to intervene with the way our body works and fix it in case of an ailment. Thanks to medical sciences and surgery, today we live longer and more fulfilling lives than our ancestors.

Since the earliest recorded instances of surgery, around 2600 years ago, it’s this trifecta – brain, vision and dexterity of our bodies, that has helped heal other humans through interventional procedures. And while this trifecta has helped up achieve what was thought impossible in the domain of surgery, it has also proven to be the core limiting factor.

This was until the advent of surgical robotics in the late 1990s and early 2000s, with Intuitive Surgical’s DaVinci Surgical Robotic system. Today, robotic surgery has become an integral (although with limited access) part of the surgical domain. Surgeons are readily switching to robotic platforms and procedures, representing perhaps one of the best examples of man-machine amalgamation. In essence, surgical robots and technologies have enhanced the surgeons’ sensory, motor and decision-making abilities enabling surgeries to be performed better, faster, and more predictably. Let us have a closer look at how surgical robots are augmenting the surgeon’s abilities, with a focus on minimal access surgical robots in particular but even other types of robots in general.

1.) Better Vision

The human eyes are limited by resolution, aperture and magnification and the spectrum of light they can detect. The earliest example of surgeons using optical augmentation was the surgical loop, enabling better magnifications for the surgical region and hence improving vision. Improvement in optics and illumination has resulted in the development of better surgical vision systems, including surgical microscopes, surgical telescopes and, critically important to minimal access surgery, the endoscope.

The surgical endoscope has enabled surgeons, in both laparoscopic surgeries as well as robotic surgery to get a clear view of the surgical area inside the body, with just a small incision on the skin. Even endoscopes have evolved over the years, providing much better resolution, with the state of the art being the 4k endoscopes; better illumination; articulating tips to look around the surgical area; special forms of visualization – e.g. in spectrums not visible to the human eye; and finally the latest – 3D endoscopes.

Some types of visualization, especially 3D vision, in the opinion of surgeons, make more sense when the surgeon is dissociated from the patient during the surgery, e.g. seated on a console than during a standard manual laparoscopic surgery. 3D vision enables surgeons to distinguish between targets that are very close to each other in the surgical field, and often have similar appearances. On the other hand, another school of thought advocates the use of 4k endoscopes as it eliminates the use of 3D glasses or immersive consoles while providing almost the same level of clinical information at a much better comfort level for the surgeon.

Add to this the fact that now surgeons can precisely control the illumination, zoom, and position of the endoscope on the fly while performing the surgery, without the need for an assistant. This eliminates the need to communicate with the surgical assistant, and hence provides more control to the surgeon himself.

It is often agreed that good vision even on its own boosts the confidence of the surgeon when performing complex procedures. Hence it reduces the surgical time drastically and also drastically reduces the chances of human error.

2.) Natural Motion

Have you ever tried to ride a bicycle with your hands crossed? I.e the left hand holding the right handlebar and vice versa. Even if you haven’t, I am sure you can guess what will happen. The reason for this is very simple, the human brain is wired to operate our extremities in a certain way. When we think left, it moves left. When it thinks right, it moves right.

The same is applicable to surgeons when performing surgeries. Imagine if the motion of the surgical tools in the hands of the surgeon was inverted. This is the exact situation that happens in manual laparoscopic surgery. The long surgical tools used in these types of minimal access surgery, are ‘fulcrum’ at the abdominal wall and hence when the motion of the surgeons’ hands is inverted.

And hence laparoscopic surgeons need years of motor skill training in order to achieve the level of control required to perform complex surgeries. Procedures that are simple in conventional open surgeries like suturing or knotting are extremely complex when it comes to laparoscopic surgeries.

This is perhaps where surgical robots make their true mark. The surgical robot is a drive-by-wire system. This means motions are first captured in a surgical console, processed and then replicated in the robot arms and robot tool tips. The processing ensures that the signals are inverted and hence match the motion vector of the surgeon’s hands to that of the surgical tool inside the patient’s body.

This brings down the training time for motor skill development for surgeons by nearly 5x, as has been thoroughly researched and published by multiple researchers. The surgeon, when looking at the console screen or looking into the immersive display almost feels as if the tooltip is their hands.

3.) Better dexterity and precision

The hands of a surgeon are almost synonymous with precision, control and dexterity. They are able to perform very fine motions with little to no vibrations. It is for this reason that some institutes/hospitals of repute often hire younger surgeons to perform a certain type of procedure e.g. microvascular surgeries – anastomosis of vessels little more than a millimetre in diameter.

It is not only about the inherent vibration in the human hand, even the surgical tools that we use to perform most surgeries have a single degree of freedom at the tooltip. A degree of freedom is the number of independent motions that a system can have. Simply put, for a surgical tool, it’s the number of joints at the tip of the tool. For standard laparoscopic tools, this number is one – the grasping.

Modern surgical robotic tools allow three or more degrees of freedom at the tooltip. This is almost analogous to the human wrist. And therefore this allows the surgeon to perform complex manoeuvres during an endosurgery as if they are using a tiny version of their wrist inside the patient’s body to perform the surgery.

The real challenge is being able to control all these joints in a synchronised manner. This cannot be done without incorporating some level of robotic control into the mix. The robotic control ‘reads’ the motion of the surgeon’s hands and then replicates the motion at the tip, by moving every actuator in a certain controlled manner.

Precision is the next big contribution of surgical robots. It is not only about how small a motion can be made but also about how repeatably can one move/orient to the same location or orientation over a period of time. Repeatability and precision ensure that surgical robots are able to perform procedures, manoeuvres and actions that are at least a dozen times smaller than what a human hand can. One way of doing this is simply by scaling the motion of the hands of the surgeon. For example, if a surgeon makes a 1 cm motion at the console, it can be replicated as a 0.1 cm motion at the tooltip. Achieving precision and repeatability is also about ensuring that the vibrations of the human hand are filtered out and that the machines themselves have little to no inherent vibrations.

4.) Machine in the Middle

This is perhaps one of the most important yet overlooked aspects of surgical robotics, and definitely one of the most controversial so to speak. It brings into discussion words like AI and Machine Learning that are often construed in a negative light, especially in the healthcare domain.

Most of us have been fascinated by the self-driving car revolution that is happening around us. If we think about it, cars have existed for a very long time, so why did it take this long to for the advent of self-driving cars? We believe it was the drive-by-wire that ultimately enabled it.

Drive-by-wire is a concept where the controller (in our case the surgeon sitting on the surgeon’s console) is connected to the actuator (in our case the complex surgical robot) only by wires passing signals back and forth – i.e. there are no physical connections like mechanical links, or hydraulics or pneumatics connecting one to the other. It also means there is a plethora of sensors at both ends ensuring that many different kinds of information like velocity, force, torque, orientation, and current, are received, recorded and processed.

Long before self-driving cars were a thing, a lot of smaller changes happened that have now become almost second nature. The fact that the car can detect if a door is open, automatically adjust the temperature in the car, detect a low pressure in the car tyre, engine trouble to something as critical as deploying airbags in case of an adverse event. This is what we like to call a watchdog.

An artificially intelligent watchdog during surgery ensures that errors are avoided to the highest possible degree. It could be something as simple as detecting the tools moving away from the surgical field and stopping them, to something as complex as detecting fatigue in the motion of the surgeon’s hands and alerting them. An AI watchdog can do things as simple as displaying or alerting the surgeon about the vitals of the patient during the surgery to complex tasks for example dynamically adjusting anaesthesia, Insufflation and drugs to ensure that the patient’s vitals are maintained.

Coming back to self-driving cars, the question remains, will artificially intelligent systems come to the surgical domain, if yes, how is it going to impact the ecosystem – the hospitals, the surgeons, and the patient? Will it be safe? Will it be ethical? To be honest there is no simple answer to this. Innovation will move in the direction of demand. It is up to us to ensure that its boundaries are set. It is our job to ensure that patient safety takes a paramount position when it comes to anything and everything in healthcare.

And this is exactly what surgical robots have done to the healthcare domain. Today we are able to do more complex surgeries, solve more complex problems, and ensure a better quality of life for millions of patients globally due to these advancements.