Endoscopy and the Minimal Invasive Revolution
AFTER A SCIENTIFIC meeting at the Josephinum, the medical academy in Vienna on 9 December 1806, seven gentlemen withdrew to a small back room, where an assistant had laid out the body of a young woman. The professors were to use the corpse to test a device developed by a German doctor, Philipp Bozzini from Frankfurt.
Bozzini called the device – comprising a candle, a speculum (a medical instrument used to inspect bodily orifices) and an ocular lens (the eyepiece that you look through on a microscope or telescope) – a ‘light conductor’. It promised to be a remarkable invention. Every doctor knew that the design of the speculum was flawed. Ideally the speculum, the light source and the eye were all aligned to prevent shadows, but then either the candle was in the doctor’s way, or the doctor’s head obstructed the light – and the candle caused the device to be too hot. But when the Herr Direktor, the Herr Vizedirektor, four honourable professors and the Herr Stabsarzt (staff physician) used Bozzini’s device to inspect the vagina and anus of the body on the table they noted delightedly: ‘The light conductor sent from Frankfurt by Dr Bozzini was presented and inspected, and it was decided to test it directly on a female corpse that had been laid out for this purpose. The results were promising beyond expectations.’
Although Hippocrates and the surgeons of the ancient world already used specula to examine bodily orifices, this satisfactory experiment with the ‘Frankfurt light conductor’ is now seen as the real birth of endoscopy, a technique that allows doctors to look inside the body with sufficient light. In the years that followed, the light conductor was improved by doctors and instrument-makers in various countries. In 1855, French surgeon Antonin Jean Desormeaux called his improved version an endoscope, which gave the name to the discipline: endoscopy, ‘looking inside’.
Almost 190 years later, on 9 February 1996, after his annual symposium on laparoscopic surgery in the Sint-Lucas Hospital in Assebroek, a suburb of Bruges, Belgian surgeon Luc Van der Heijden is sitting a little nervously at a small table at the front of the auditorium. For this official occasion, he has changed out of his operating clothes and put on a smart suit. Television cameras are focused on him and technicians are trying to make contact with the Sint-Antonius Hospital in Nieuwegein, 150 kilometres away in the Netherlands. The communication link has been made possible by relatively new technology, the Integrated Services Digital Network (ISDN). Dutch surgeon Peter Go appears on the screen. The image is a little shaky and the sound is tinny as he explains that his patient is already anaesthetised and ready on the operating table. He has a groin hernia, which is going to be repaired by laparoscopic (keyhole) surgery. The camera in the patient’s abdomen will not be held by human hands, however, but by a robot – and Van der Heijden is going to operate it from Belgium. While the members of Go’s operation team in the Netherlands stand with their arms folded in front of them, with the press of a button in Belgium the camera moves up and down and from left to right in the man’s abdomen.
Although the laparoscopic hernia repair was eventually completed by the Dutch surgeon Go, this remote operation of the camera was the world’s first experiment with telesurgery. Now, twenty years later, complex operations – such as removal of the rectum, the adrenal glands, parts of the large intestine, or a gastric bypass – are performed laparoscopically as standard procedure. That means they can be performed more quickly (usually within one or two hours) more safely and more easily than was the case with a conventional, open operation. How did we get to this stage?
You don’t get far with an instrument that requires lighting a candle, and in 1879 Viennese instrument-maker Josef Leiter and urologist Maximilian Nitze solved the problem once and for all by moving the light source from outside the body, to inside the bodily cavity itself. Leiter and Nitze developed a cystoscope, an instrument that enabled them to look inside the bladder through the urethra with the use of a glowing wire (this was almost six months before Thomas Alva Edison would invent the light bulb) to produce light, which was cooled with water. The cystoscope made Leiter world famous. He persuaded the assistant of the greatest surgeon in the world, Theodor Billroth in Vienna, to help him develop the ultimate endoscope: a gastroscope, an instrument to look inside the stomach. Leiter and the assistant, Johan von Mikulicz, constructed a tube with a water-cooled light on the end. As the patient had to swallow the long tube in its entirety, von Mikulicz performed the first gastroscopy on a circus sword-swallower in 1880. Von Mikulicz would use the gastroscope to examine the stomachs of hundreds of patients, sometimes together with his pupil Georg Kelling.
An examination with Von Mikulicz’s rigid tube must have been a terrible experience for the patient. He would be laid on the table on his back, with his head hanging over the edge. Then the metal tube, which was a good 60 centimetres long, would be pushed through his open mouth, down his oesophagus and into his stomach. The stomach was then made visible by pumping it up with air and switching on the light. If the patient lay still, did not panic or choke, the doctor would have enough time to inspect part of the stomach. Not much, but more than anyone had ever dreamed of until then.
Towers and trocars
A laparoscopic operation relies entirely on technology. It requires four devices, which are mostly stacked on top of each other on a movable trolley known as a laparoscopy tower. At the top is the screen, and below the camera unit, to which the handheld digital camera head is connected, is the insufflator, which inflates the abdomen to a constant pressure with carbon dioxide, and the light source. Three cables run from the tower to the operation: the cable from the camera, a fibre-optic cable for the light, and a tube for the carbon dioxide gas. The camera and the light cable are connected to the laparoscope, a tubular instrument about 10 millimetres in diameter and 30–40 centimetres long, with a lens system for the image and light. To gain access to the inflated abdominal cavity, devices called trocars are inserted through the abdominal wall. These are tubes between 5 and 12 millimetres in diameter with an airtight valve, through which the laparoscope, clamps and other instruments can be placed in the abdomen. Electricity is used for cutting and cauterising in the abdomen. That is why the gas in the abdomen may not contain any oxygen and all the instruments and trocars are electrically insulated. The trocars and the laparoscopic instruments are minute and mechanically complex, and as they are easily damaged and difficult to clean, many are disposable and are discarded after each laparoscopy. That makes laparoscopic surgery expensive, but that is paid back by the fact that patients spend less time in hospital.
The next milestone was actually a by-product of a different idea. Experiments inflating the abdominal cavity with air had been carried out for many years in a process known as insufflation; it was tried as a treatment for tuberculosis in a time when experimentation was all that could be done to combat wasting diseases, and it was even alleged to have been successful in some cases. Either way, it had become clear that inflating the abdomen with air could do little harm. Von Mikulicz, too, had experimented with insufflation and had used the same air pump for his gastroscope. His assistant Georg Kelling had come up with the idea of raising the air pressure in the abdominal cavity higher to stop internal haemorrhaging in the abdomen, and had experimented with this treatment on dogs.
First, Kelling generated a rupture of the liver in the test animal. Then he inflated the abdominal cavity and waited. But the dogs kept dying. He did not understand why the idea would not work and wanted to know exactly what happened in the abdominal cavity. So he inserted a Nitze-Leiter cystoscope through the wall of the inflated abdomen to see it with his own eyes. What it showed was that the air pressure did not press the rupture in the liver closed at all. As he watched the dog bleed to death, he realised he had invented something new.
On 23 September 1901, Kelling repeated the experiment in front of an audience at the 73rd Congress of the Naturalist Scientist’s Medical Conference in Hamburg, but now without rupturing the liver. He inflated the abdominal cavity of a healthy dog with air, inserted a cystoscope through the abdominal wall and keyhole surgery was born.
It is difficult to imagine that laparoscopy, which is now irrevocably part of modern surgery, was once completely the domain of non-surgical internists. When Kelling performed that first laparoscopy experiment in 1901, there were few options for supplementary tests to support a diagnosis. Blood tests were still at an embryonic stage, X-rays did not show much of value when it came to the abdomen, and microscopic study was only possible after a patient had died. Laparoscopy was therefore a welcome new method that facilitated significant progress in medicine but which, as yet, had little to do with surgery, and was instead used to examine the liver and other organs close up to determine how far a disease had spread. And the procedure was not without teething problems: in 1923, an abdomen inflated with oxygen briefly caught fire, fortunately doing little damage to the patient. Since then, carbon dioxide – which cannot explode – has been used.
It was not surgeons who took the next step – from diagnostic laparoscopy (looking inside the abdomen to see what there is to see) to therapeutic laparoscopy (looking inside the abdomen to do something) – but gynaecologists, because it is not only the liver that can be inspected with a laparoscope through the navel: there is also a perfect view of the womb and ovaries. All you have to do is tilt the operating table with the head downwards, so the intestines shift position from the lower to the upper abdomen. And because, unlike internists, gynaecologists were accustomed to performing operations, it only required a small step for them to conduct minor operations with the aid of a laparoscope. They started with laparoscopic sterilisation, which entailed tying off both fallopian tubes, and then went further, lancing cysts on the ovaries and removing ectopic pregnancies. As they got better at it, they performed increasingly complex procedures. German gynaecologist Kurt Semm removed uterine fibroids and was eventually able to remove a whole womb laparoscopically. In 1966, he marketed the first automatic insufflator, the CO2-Pneu-Automatik, which inflated the abdomen with carbon dioxide and kept it at a safe constant pressure. Semm also developed the first laparo- trainer, a model in a box with which gynaecologists could learn how to perform laparoscopic operations.
In the Netherlands on 2 December 1975, Henk de Kok, a surgeon who learned laparoscopy from his brother Jef, a gynaecologist, performed the world’s first laparoscopically assisted appendectomy at the hospital in the Dutch town of Gorinchem. With the laparoscope in one hand, he located the appendix and, with the other, he determined the location on the abdomen where he could make a minuscule incision through which he could extract the appendix, watching all the time through the laparoscope. His fellow surgeons thought the whole procedure scandalous.
Laparoscopy had never enjoyed much popularity among surgeons. Because you always had to hold the laparoscope with one hand, you only had one hand free to perform the procedure. Surgical applications of laparoscopy only really became possible with the advent of a completely new technology. In 1969, George Smith and Willard Boyle invented the charge-coupled device, better known as the CCD chip, which enables images to be digitalised and processed. The first CCD camera came on the market in 1982 and, within a few years, the latest models were small enough for a surgeon’s assistant to hold the camera while the surgeon stood upright, watching the screen. Still, many surgeons were not convinced. The first video-assisted laparoscopic cholecystectomy – the removal of a gall bladder with a video camera and a television screen – was performed by Phillipe Mouret in Lyon in 1987. Mouret was in fact a gynaecologist, but the successful operation set many a surgeon’s hands itching and, within a few years, laparoscopy had spread like wildfire.
The cholecystectomy became the most commonly performed laparoscopic operation in the world. It only requires three or four tiny incisions, altogether no bigger than four centimetres, while the incision for a classic gall bladder removal was longer than 15 centimetres. The public noticed the difference immediately, as the innovation was big news in the media. Patients experienced much less pain and no longer had to spend a week in hospital, but could go home the next day. It was the start of a trend that unleashed a genuine revolution. Minimal invasive surgery – performing the maximum surgical intervention with the smallest possible operational technique – became the magic word in twenty-first century surgical practice. It sounds so logical, but it was only possible as a result of complex high-tech developments.
Now, there is not a single organ in the abdomen that cannot be operated on laparoscopically. In 2001, French professor Jacques Marescaux built on Van der Heijden and Go’s feat by performing a trans-Atlantic operation which – with an obvious sense of spectacle – he called Operation Lindberg. From New York, he controlled a robot in Strasbourg, performing a laparoscopic cholecystectomy on a female patient nearly 4,000 miles away. More recently, without making an incision, Marescaux removed a gall bladder endoscopically through an opening in the vagina. Yet, despite surgeons’ best efforts to showcase surgery as an innovative discipline, it is radiologists and cardiologists who have made the most spectacular progress in minimal invasive techniques in recent years. They can now replace a heart valve through a puncture in the groin, stop a bleeding spleen, remove a stone in the bile duct through the liver and treat a rupturing aortic aneurysm as if it is the easiest thing in the world, without the need for an operation at all.
As for non-surgical physicians, they stopped using diagnostic laparoscopy around the same time that surgical laparoscopy with a video camera began, but not because surgeons took it over from them. Other technologies had been developed, including ultrasound scans and computed tomography (CT) scanning, which give a much clearer image of the liver than laparoscopy.
Georg Kelling, the man who discovered laparoscopy, died at his home in 1945 during the bombing of Dresden. His body was never found.