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OBGYN.net Conference CoverageFrom the ESHRE 2000 Conference Bologna, Italy
Dr. Hans van der Slikke: "We are here at the ESHRE 2000 in Bologna, Italy and next to me is Dr. Mark Emanuel from Haarlem, in the Netherlands. He presented a revolutionary tool for removing polyps and fibromas from the uterine cavity. Dr. Emanuel, could you tell us about your invention?"
Dr. Mark Emanuel: "Yes, I would be very pleased. The rationale of developing a new technique is that there are some difficulties with the current technique. The current technique is resectoscopy which is a technique originally developed for urological tools that the last decade is used quite widely in gynecology to remove intrauterine tissue like endometrial polyps, mucous myomas, or even the entire lining of the uterine cavity - the endometrium. The problems with this technique are that for most gynecologists this technique is rather difficult to learn, and it's not quite widely offered during training. So many gynecologists have to train themselves after their residency, and that's why it is not used as much as it could be so I would say that there are still too many hysterectomies performed instead of resection of intrauterine pathology."
Dr. Hans van der Slikke: "What are the difficulties of this conventional technique with a loop or another thing like this?"
Dr. Mark Emanuel: "What you do is you cut tissue with a small wire loop which has a high frequency current on it which is monopolar. The problem is that cutting out tissue is quite easy but then the tissue remains in the uterine cavity and you have to remove that by the loop and that's rather time consuming and it needs a lot of handling. Every time you have to go out of the uterus with the instrument and then in again, and meanwhile, there are blood clots you have to clear. You have to visualize the situation where you did your surgery and that takes time, it's difficult, and sometimes it's even annoying because it can take up to 25-40 times of going in and out of the uterine cavity during a normal procedure."
Dr. Hans van der Slikke: "And you use a lot of fluid."
Dr. Mark Emanuel: "Yes, that's another problem because it's a monopolar technique, we can only use non-conducting electrolyte free solutions - irrigation and distension solutions. If these solutions enter the blood vessels which they always do because you have to work under a certain pressure to have enough visualization of the cavity and distension, these liquids will cause a dilution of the blood and they will give electrolyte disturbances which can lead to cerebral edema and eventually, although very rare, death even. Therefore, a very precise monitoring of the fluid balance, the fluid that goes in and the fluid that goes out, is necessary during these techniques."
Dr. Hans van der Slikke: "Do you know what the rate of this very serious complication is?"
Dr. Mark Emanuel: "They are rare but it is a procedure for a benign indication so of course every fatal case is a disaster, and these cases are rare, especially the cases where death occurs but a lot of patients have more than 500 ml intravasation. Oloff Istraf from Norway demonstrated very nicely that from 500 ml onwards you can see cerebral edema on the CT scan, and many of my patients have more than 500 ml intravasation and they suffer extreme nausea, for instance, after the procedure, which in my opinion is caused by this cerebral edema which is temporary."
Dr. Hans van der Slikke: "So now you have this new technique and you can use a lot of fluid with it."
Dr. Mark Emanuel: "Yes, the two main features of this technique is that it is a mechanical technique that does not use high frequency electricity, and the second feature is that the technique in itself removes the tissue out of the uterine cavity. You could say it cuts and aspirates the tissue out of the cavity. The intrauterine shaver is made of two small tubes with an outer diameter of about 4 mm and these tubes rotate in each other. That is to say the inner tube is rotating inside of the outer tube and at the end there is an opening, which is sharpened. Both tubes can cut tissue and there's also a vacuum source connected to the shaver system. So the tissue is sucked into the cutting opening and by the rotation of the inner tube the tissue is cut and by means of the vacuum source it is aspirated. So the main advantages are that the technique is very easy because the instrument does the work, you only have to press the instrument against the tissue, polyp, or the fibroid. The other advantage is that we can now use more physiologic fluids like saline solution, and intravasation is not important anymore because that's the same solution you use, for instance, in an IV line."
Dr. Hans van der Slikke: "By not using coagulation, doesn't this cause a lot of bleeding?"
Dr. Mark Emanuel: "Many questions were asked about that topic. What we have noticed with resectoscopy as well, as long as you're able to resect the pathology completely or even an incomplete resection, for instance, a fibroid which is located more or less in the intramural part of the uterine wall, that myometrial contraction in all cases is capable of stopping the bleeding. If you compare it, for instance, with a placental bed after birth, which is quite large, in such cases bleeding is always stopped by the uterine contractions. So uterine contractions are very effective in stopping bleeding; they do that every month, they do that after birth, and they can do that after intrauterine surgery as well. If you, for instance, look at the form of D&C where we went in with a curette and scrapped the tissue of the uterine wall, we were never concerned about not using electrocautery to stop bleeding."
Dr. Hans van der Slikke: "You talked about myomas in the uterine wall, how could you access these kind of myomas unless you use the shaver?"
Dr. Mark Emanuel: "If the intramural extension is quite deep, problems will arise with resectoscopy as well because if you go deeper into the wall, you will have more intravasation. The average gynecologist would not like to go deep into the myometrium with the loop of the resectoscope. Normally, this is only for specialists who are really very experienced in going into the myometrial wall to resect these intramural parts. Many of my colleagues who do resection but not very often resect just on the level of the wall of the cavity and then they wait for two or three months to see what happens. There is a Danish study on 150 of such cases, and in two-thirds of the cases the problems are dissolved and the patient comes back without any complaints. If you do a vaginal ultrasound after two or three months, the intramural part is expelled in the cavity and it has become necrotic and vanishes. So these remnants can cause problems but it's not often, and if they still cause problems, there is always the possibility to do a second procedure after two or three months. In resectoscopy these fibroids are often treated as a two-step procedure, and with the shaver system, of course, it's also possible to do it in a two-step procedure. I think the second procedure is probably even simpler than the first one because the fibroid remnants are softened and they are less vascular. They are softer so they can be shaved away quite easily."
Dr. Hans van der Slikke: "Do you have any idea when your invention will be commercially available?"
Dr. Mark Emanuel: "What is happening at this moment is that the shaver industry is looking at it."
Dr. Hans van der Slikke: "Braun and Phillips or do you mean the hysteroscopy industry?"
Dr. Mark Emanuel: "I mean the medical shaver industry and similar systems are made for orthopedic surgery and ENT surgery. The market leader in that field is Smith and Nephew and they are looking at the prototype at this moment. They helped me in developing the prototype as far as the shaver blade is concerned. We made the endoscope ourselves but Smith and Nephew made the prototype of the blade, the length of the blade. They are very interested in the technique and they want to see if they can develop better blades, for instance, for the different types of tissue and even burrs where you can scrape off the endometrial lining. There will probably be a system for endometrial ablation as well, and they expect that when everything is going well and the clinical studies are okay, we will have a product launch somewhere in the second half of next year."
Dr. Hans van der Slikke: "Are there still other advantages of this technique?"
Dr. Mark Emanuel: "In the future, we hope to diminish the outer diameter of the hysteroscope we are now using which is 9 mm and comparable to the resectoscope. If we are able to reduce the outer diameter of the system to 8 mm, then due to the short period of operation, it is possible to do these procedures probably in an outpatient setting with local anesthesia. I think if you compare this system with other new systems which have been developed because of the difficulties with resectoscopy, for instance, the balloon therapies for endometrial ablation or VersaPoint's technique for vaporization of tissue intrauterine, the big advantage of this technique is that the histology specimen is preserved so it is still possible to do a histological examination on the tissue, which has been shaved away. That is not possible if you compare it, for instance, with the VersaPoint technique where the tissue is vaporized."
Dr. Hans van der Slikke: "Always balloons where it is burned, cooked, and so there are…<CUT???>"