Q&A: Dr George Webster
Q&A - 12TH JULY 2017
Consultant gastroenterologist and hepatologist at The London Clinic on how treatment of conditions affecting the bile duct has been transformed by next-generation endoscope technology
Interview: Viel Richardson
Images: Orlando Gili
What’s your role?
I’m a consultant gastroenterologist and hepatologist with a particular interest in diseases of the bile duct and pancreas.
What is the bile duct and what conditions can affect it?
Bile is a waste product of the liver. The bile duct drains it from the liver into the top part of the gut called the duodenum. There are a wide range of diseases and conditions that can affect it. Benign problems include narrowings called ‘strictures’, or obstructions. Stones that develop in the gall bladder can pass through into the bile duct causing blockages, which can result in severe pain. About 10% of the adult population have gallstones, and in the vast majority of cases there are no symptoms and nothing needs to be done, but when these stones pass through into the bile duct, this cannot be resolved with a simple operation—and that’s where the procedures that I’m involved in come in.
What about malignant problems?
Narrowings in the bile duct can be caused by malignant or cancerous disease. For example, the lower part of the bile duct runs through the pancreas and if, unfortunately, you get a tumour in the pancreas, this can squeeze the bile duct, causing strictures, which in turn can cause jaundice and other problems related to poor drainage, including dark urine and pale stools. There are also other types of malignant cancerous strictures including bile duct cancer and secondary tumours. These can develop in the internal wall of the bile duct, or outside the duct pressing inwards.
Not all strictures are due to cancer. The difficulty is that cancerous and non-cancerous strictures of the bile duct often cause symptoms that are very similar, although the treatment is of course completely different. Therefore, there is always a challenge to make a clear diagnosis.
How would you traditionally have investigated these issues?
For the past 30 years, our main tool for managing stones in the bile duct has been a type of endoscopy called an endoscopic retrograde cholangiopancreatography (ERCP). This allows us to inject dye up the bile duct and use x-rays to look for stones. If we find them, we pass a thin tube with a ‘balloon’ at the end up the bile duct to a position just above the stone’s location. Then we inflate the balloon and slowly drag it down, bringing the stone with it. This is actually a very effective treatment in many cases. We also have special baskets we can use to crush the stones in situ.
However, in some patients it is not possible to remove the stones using conventional ERCP. In the past, this has resulted in patients either having multiple procedures, or the patient being put through very complex open abdominal surgery to remove the stone. This is the area where a new system we have at The London Clinic called SpyGlass has a very important role to play.
What is SpyGlass?
It is a tiny camera on the end of a very thin 3mm steerable endoscope called the SpyScope, which we feed down the middle of a traditional endoscope. For the first time we can see inside the bile duct without an operation.
Can you attach tools to the scope?
Yes, we can. For example, when dealing with gallstones we can attach an instrument called an electrohydraulic lithotripter. We can manoeuvre the SpyScope right up to the stone, and fire shock waves at the stone to break it up. We then use balloons or baskets to remove those fragments.
What about dealing with strictures?
The crucial question here is whether it is benign or malignant. If the cause is benign, many strictures can be opened up with balloons, and we can use stents to keep them open. But if it is a cancer, then clearly we need to be in a position to give other treatments, which may include curative surgery or chemotherapy.
Curative surgery is very major surgery, and we don’t want to put people through that unless there is a high level of probability that they do have cancer. The traditional way to decide whether a stricture is cancerous is brush cytology, in which an endoscope with a tiny brush is used to take scrapings from the lining of the stricture. This gives us a reliable answer in no more than 30-40% of patients. SpyGlass technology changes this, because we are able to inspect the lining of the bile duct. This allows us to make a very clear assessment as to whether it has features that suggest inflammation or cancer. We also have biopsy forceps that we can pass down the SpyScope, which allow us to take direct samples from any abnormal areas that we see.
This sounds like a significant step forward.
A huge step. We can pinpoint the abnormal area and take biopsies precisely where we want to. The pathologists who make the diagnoses are much happier having a biopsy rather than brush cytology, which gives individual cells but not a sample of the tissue as a whole. Being able to visualise strictures and take biopsies significantly improves diagnostic confidence. Some studies suggest that in 80% of cases, the consultant is confident in the benign or malignant diagnosis. We have not discarded the traditional techniques, but increasingly in specialist centres in the UK, we are incorporating SpyGlass into the assessment of patients with suspected malignant strictures.
Is this a new technology?
Cholangioscopes were actually first introduced in the late eighties, but they fell out of use because they were unreliable, fragile and extremely expensive. What we have now is a world away from those early tools. The latest generation, the SpyGlass DS, offers excellent visualisation, is extremely reliable and is much more manoeuvrable than previous systems. Another advantage is that previous systems required two endoscopists to work at the same time: one handling the ERCP scope and the other handling the cholangioscope. Now one endoscopist controls it all.
So, how do you control it?
Each endoscope has two steerable wheels, allowing four directional movements. Once the main endoscope had taken us as far as it can, we switch to the SpyGlass endoscope controls and use it to complete the procedure. The traditional endoscope stays in the duodenum while we advance the SpyGlass scope up the bile duct and right into the liver if we need to.
How is this new technology beneficial to the patient?
One area is the ability to treat stones within the biliary tree that previously would have been difficult without an open operation. But the biggest impact has been a better patient journey. The diagnoses are being reached more quickly and the treatment can be given more accurately and less invasively than was possible in the past.
Can you explain how?
Take a patient who has been told that they have a suspected tumour within the liver. The suggested treatment could be an operation to remove half the liver. Now, we can look, see what is actually there and take a biopsy. There have been occasions when what was thought to be a tumour causing a blockage was actually a stone and we have been able to get rid of the stone there and then. In one procedure, we were able to allay the patient’s anxieties about a tumour and treat their problem, all while avoiding a complex and life-changing operation.
I also think of it as a piece of kit that increasingly allows me to finish the job. Bile duct stones are a problem which can take multiple attempts to cure. One patient I saw had been through eight procedures that had failed to resolve their issue. Using this system, we resolved their problem on the first visit. When I examined the area visually, it became immediately clear why previous procedures had failed and would continue to fail. I was able to devise a different approach that was successful. That’s a very satisfying thing to be able to do.
What improvements do you expect to see down the line?
I think in the future, the SpyGlass will allow many more patients to have bile duct stones cleared without constantly returning for multiple procedures, as can still be the case today. I think it will become an increasingly important procedure in the assessment of patients with strictures and I think as the technology advances, we will develop new treatments and procedures.
I can see a time when we are able to not just investigate strictures, but are actually able to treat malignant ones too. There’s a lot of enthusiasm in that area, and a lot of research going on to create new tools that can be attached to the SpyGlass, which will increase its capabilities even further.