Bladder cancer is the sixth most frequent form of cancer in the US, according to an online edition for girls and women aged 14 to 35 years Pannochka. net Treatment of bladder cancer is very expensive, and the basic methods used in this form of cancer have not undergone significant changes for many years.

The interdisciplinary collaboration of engineers and physicians at Vanderbilt University and Columbia University led to a drastic change in this situation. Associate Professor of Vanderbilt University. Siiman and his team developed a prototype of a telerobotized platform that can penetrate into the natural openings of the body (urethra) and provide surgeons with excellent access to tumors.

This allows you to repeatedly increase the effectiveness and safety of treatment of bladder cancer.

The new system is designed for both diagnosing neoplasms in the bladder and for removing the tumor - the so-called transurethral resection.

Siiman said: "When I observed a modern transurethral tumor resection, I was amazed. The tools are very coarse and large, and the patient's tissue is squeezed and stretched by the surgeon ".

Inspired by experience, the engineer tried to develop a system that uses a miniature robot to perform this fine operation. The possibilities of the new system have been described in the author's article "Development and evaluation of a telerobotized platform for minimally invasive transurethral surveillance and intervention". The article was published in a recent issue of the journal IEEE Transactions on Biomedical Engineering.

A specialized telerobotized system "does not exclude the surgeon's hands from the process, but improves their capabilities". So commented on the emergence of the novelty Duke Herrell, associate professor of urological surgery and biomedical engineering, who specializes in minimally invasive oncology at the Medical Center of Vanderbilt University.

The traditional method that Seiman observed includes the introduction of a flexible tube (resectoscope) through the urethra into the bladder. The instrument contains several channels that circulate the fluid, give access to the endoscope and instruments that make a biopsy or remove (cauterize) tumors. In some cases, instruments with a fiber laser are used to kill cancer cells.

The endoscope can allow a good view around the opening of the urethra, but access to other areas of the mucosa is not so convenient. The physician must press or twist the endoscope to examine the distant parts of the bladder mucosa. Such actions are also necessary for resection of tumors located in hard-to-reach places.

If the surgeon conducting the endoscopic biopsy determines that the tumor has sprouted through the muscle layer of the bladder, then a cystectomy can be prescribed - removal of the bladder by the incision of the abdominal wall. Often this is done by a conventional surgical robot. But if the doctor believes that the tumor affects only the mucosa of the bladder, then he can remove it with a resectoscope.

Bladder cancer is a very expensive disease. The high cost is due to the fact that the cancer is very stable, so patients need a long observation, and often repeated operations. Among the factors that prevent cancer from curing at the first attempt, difficulties in recognizing the exact boundaries of the tumor during transurethral resection. This leads to the fact that part of the cancer cells on the border of the tumor can remain untouched.

Dr. Herrrell says that a long resectoscope makes a transurethral resection of a bladder tumor an inconvenient and complicated procedure.

The telerobotized system was created especially for operations in such conditions. The machine itself is similar in size and shape to a small thermos, but its working end is only 5.5 millimeters in diameter, and includes a segmented mechanical "arm". The robot's thin arm can turn and bend in different directions, directing the instrument to the desired point. At the end of the arm is a light, a fiber laser for cauterizing the tumor, a fiber endoscope for inspection and miniature forceps for taking a tissue sample.

Engineers report that they can monitor the position of the robot's arm, changing it by a fraction of a millimeter. This accuracy is more than enough for a successful operation. They demonstrated that the device is able to take tissue samples for biopsy and successfully burn small tumors with a laser.

The fiber endoscope receives an image of 10,000 pixels, which is transmitted to the monitor in the operating room. The endoscope rotates freely and allows you to magnify the image, so examination of distant areas of the bladder becomes a relatively simple task. Now scientists are working to further improve the device. The possibility of replacing the fiber endoscope with a miniature digital camera.

In the future, researchers are going to include additional imaging techniques to improve the ability of the robot to identify the edges of the tumor. It may be possible to introduce fluorescent endoscopy or optical coherence tomography (OCT), which uses optical waves of the infrared range. Also considered an additional application of ultrasound.

In addition to these extensive diagnostic capabilities, researchers are planning to give the robot's hand a tactile sensitivity. Enhanced feedback technology will measure the degree of pressure of a mechanical arm on tumor tissue. Dr. Andrea Baggio used this opportunity to develop algorithms that allow the robot to masterly "probe" the tumor, following exactly along the tumor boundary.

Dr. Herrrell says: "Surgeons usually identify the border of the tumor with an accuracy of about a millimeter, but our robot is able to do this with an accuracy that is an order of magnitude greater than the person's capabilities. The introduction of additional technologies will help determine the border of the tumor at the cellular (!) Level ".

Now the team of scientists plans to teach the robot to determine the boundaries of the tumor and remove the malignant cells along with the finest strip of surrounding healthy tissue.

Throughout this process, the surgeon will only have to guide the smart machine and give her commands.

In addition, engineers are working on numerous security measures of the tele-robotic system. For example, the operator can set the maximum depth of the cut with a laser and other parameters that the machine itself will follow. These security measures are a priority for Siiman: the robot must penetrate into the human body and absolutely safely interact with it.

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