【4K Laparoscopy】Application Advantages and Development of 3D and 4K Laparoscopy in Colorectal Surgery

【Summary】

In recent years, the progress and application of vision platform systems such as 3D laparoscopy and 4K laparoscopy have provided the necessary technical basis for the precise treatment of laparoscopic colorectal surgery. 3D laparoscopy and 4K laparoscopy make it possible for the precise dissociation of layers, the complete anatomy of the mesentery, and the precise protection of nerves. From the perspective of the development of equipment engineering technology, it is necessary for the safety and radical cure of laparoscopic colorectal surgery. guarantee. It is believed that the continuous innovation and development of these technologies related to minimally invasive surgery will certainly play a huge role in promoting the technological progress of colorectal surgery in the future.

Minimally invasive techniques have been widely used in colorectal surgery, and have been recognized, from lymphatic dissection to digestive tract reconstruction and other aspects have been superior or equivalent to traditional open surgery. Although the occurrence, development and prognosis of diseases have their inherent laws, the diagnosis and treatment of diseases cannot be completely determined by the development of technology, but it is undeniable that the development of technology has played a role in promoting the progress of disease diagnosis and treatment. As the saying goes, if a worker wants to do a good job, he must first sharpen his tool. In recent years, technological innovations related to minimally invasive technology have emerged one after another, and the equipment platform has been continuously updated and developed, which has promoted the development of surgery, especially colorectal surgery. Among them, the advancement and application of vision platform systems such as 3D laparoscopy and 4K laparoscopy are particularly important, providing the necessary technical basis for the precise treatment of laparoscopic colorectal surgery. This article discusses the application of 3D and 4K laparoscopic platforms in colorectal surgery in recent years.

1. The application advantages and development of 3D laparoscopy in colorectal surgery

With the continuous development of three-dimensional imaging (three-dimensional imaging, 3D imaging) technology, the application in minimally invasive surgery is becoming more and more extensive. Compared with traditional two-dimensional laparoscopy, 3D laparoscopy can provide a three-dimensional sense of the surgical field and a sense of spatial depth of surgical operations, making up for the shortcomings of two-dimensional images in spatial positioning and anatomical structure identification. However, limited by the objective conditions such as early equipment and technology, the low resolution of 3D images in the 1990s was easy to cause visual fatigue and discomfort to the operators, which greatly affected its clinical promotion at that time. In recent years, the continuous development of technology has greatly improved the above shortcomings.

(1) Application advantages of 3D laparoscopy in colorectal surgery

1. Colon surgery: 3D high-definition resolution plus three-dimensional effect, in addition to blood vessel separation and lymphatic dissection, it brings a clearer picture to the operator, and can better distinguish the front and rear levels of the tissue structure, and the lacunar structure can be more clearly identified. Precise, the chance of vessel wall damage is greatly reduced. Regardless of left colon or right colon surgery, more and more emphasis is placed on the identification and dissection of Toldts space, Gerota space, prepancreatic space, and prepancreaticoduodenal space; , Accurately identify abdominal wall fat or mesocolon fat, in order to separate the mesocolon and complete resection, to achieve the most accurate anatomical separation. However, the above-mentioned gaps and various layers of adipose tissue are originally overlapping. Although the difficulty of distinguishing gaps in 2D state is lower than that in laparotomy, it still requires the operator to have solid anatomical knowledge and rich surgical experience. Walk accurately between the gaps during surgery. In the state of 3D laparoscopy, the fascia tissue and different fat structures in each gap are obviously different, which are very easy to identify, the probability of misjudging the gap level is reduced, and the operation process will be much smoother.

2. Rectal surgery: 3D high-definition laparoscopic surgery restores the three-dimensional surgical field of vision in real vision, and has a magnifying effect, which overcomes the visual difference and inconvenience caused by the two-dimensional field of view of traditional laparoscopy, and facilitates better identification during the operation. Anatomical tissue makes it easier to dissect 253 groups of lymph nodes during laparoscopic radical resection of rectal cancer, and it is more convenient to finely identify the autonomic nerve, and to identify the levator ani muscle attachment point more clearly during ISR surgery or Miles surgery. During the operation of low rectal cancer, if the lens is too far away, the operator cannot see and distinguish the anatomical relationship. If the lens is too close, it is easy to be blurred by the smoke generated by the ultrasonic knife, and the mirror needs to be wiped repeatedly. The operation time is prolonged, and this disadvantage is particularly prominent in patients with large tumors and low rectal cancer, especially in obese patients with narrow pelvis.

The 3D high-definition laparoscope provides a high-definition surgical field of view for minimally invasive surgery, and has a three-dimensional visual effect, especially improving the depth perception of the laparoscopic surgeon. The field of view increases the accuracy of the operation and reduces the operation time. The lens of some 3D laparoscopes is rotatable, which is especially convenient for rectal cancer. When cleaning the root of the inferior mesenteric artery, the angle can be slightly adjusted to achieve the visual effect of 30° of ordinary 2D laparoscopy. When freeing the pelvic floor and anterior rectal wall, the ordinary 2D laparoscope needs to reverse the lens to see part of the field of view, and most of the operating points are located in one corner of the display screen at this time, while the rotatable 3D laparoscope is curved upward through an appropriate angle. A satisfactory visual effect can be achieved at 60° ~ 90°, and the surgical operation point can generally be located in the middle of the display screen, which is particularly prominent in the operation of low rectal cancer.

(2) The development status of 3D laparoscopy in colorectal surgery A meta-analysis including 6 prospective studies showed that: 3D laparoscopy shortens the operation time of colorectal resection (radical resection of colorectal cancer) [-13.4min; (95% CI - 26.05min, -0.83min)], but did not significantly increase the number of lymph node dissections, nor did it reduce the incidence of postoperative complications. The main disadvantage of this study is that only 1 RCT was included. A single-center RCT study in China found that 3D laparoscopic radical colorectal resection was comparable to 2D laparoscopy in terms of operation time, intraoperative blood loss, number of lymph node dissections, and postoperative hospital stay. Most of the studies on the application of 3D laparoscopy to colectomy (radical resection of colon cancer) are retrospective studies, and its advantages include: reducing intraoperative bleeding, increasing the number of lymph nodes dissected in D3 radical resection, and shortening the time of laparoscopic intestinal anastomosis. Many domestic studies have also shown that 3D laparoscopic colon cancer radical resection shortens the operation time and reduces intraoperative blood loss compared with 2D laparoscopic surgery. At the same time, 3D laparoscopy is considered to improve the CME completion rate (using the N.P. West grading method) in radical resection of right colon cancer, which is an advantage of 3D laparoscopy in terms of specimen pathological quality.3D laparoscopy has certain advantages in the identification and anatomy of Toldts space, retrocolonic space, and anterior pancreaticoduodenal space, especially the difference in fascia tissue and different fat structures in each space in obese patients. A single-center RCT study concluded that 3D laparoscopy can shorten the operative time of radical rectal cancer. Domestic retrospective studies suggest that 3D laparoscopy can shorten the operation time and reduce the amount of intraoperative blood loss in radical rectal cancer surgery. Other advantages of 3D laparoscopy in radical rectal cancer include: shortening the time of lateral lymph node dissection, increasing the number of lymph nodes dissected, reducing postoperative urinary dysfunction, accelerating postoperative recovery, and reducing long-term sexual dysfunction. Some studies have shown that the positive rate of peripheral resection margins of postoperative specimens in the 3D group is lower than that in the 2D group, but there is no statistical difference in the 3-year overall survival (OS) between the two groups. The prognostic perspective reflects the value of 3D laparoscopy. However, the polarized glasses currently worn in most 3D laparoscopic devices have a light attenuation effect. The attenuation of the display screen brightness leads to image distortion, which affects the accurate judgment of the anatomical structure; the brightness attenuation of the surrounding environment causes the operator to interact with the off-screen environment Will switch between different visual experience, prone to dizziness and other discomfort.In addition, the water vapor exhaled by the surgeon is easy to condense into water mist on the lens, which affects the clarity of the image and the smoothness of the operation. In view of the above-mentioned defects, a glasses-free 3D imaging technology based on a barrier grating and a cylindrical lens array technology and a human eye or face tracking technology, that is, naked eye 3D, emerges as the times require. The author's team has carried out a certain number of cases of naked eye 3D laparoscopic radical resection of colorectal tumors. The initial experience is that the image is clearer, brighter and more realistic, which is more conducive to surgery, especially to lymphatic dissection. However, naked-eye 3D also has its shortcomings: First, naked-eye 3D only saves the chief surgeon from wearing glasses. If other people need to use naked-eye 3D at the same time, they need more face or human eye recognition equipment and display screens, which greatly reduces the need for glasses. Due to the limitation of current technology, naked-eye 3D will have a certain impact on the resolution, and it is impossible to rotate the lens section to change the viewing angle. In view of these problems, naked eye 3D laparoscopy still has a huge space for continuous improvement, but it still has a good development prospect.

2. Application advantages and development of 4K laparoscopy in colorectal surgery

In recent years, 4K imaging technology has been applied to the laparoscopic camera display system, which has greatly improved the surgical field. 4K laparoscopic equipment can make up for the shortcomings of conventional high-definition laparoscopy in image description, enhance the description of the details of the surgical field, and present a clearer and more realistic surgical field of vision that is better than what the naked eye can see on the big screen, improving the surgeon. The operational sense of the surgical field brings further development to the laparoscopic surgical technique.

1. Advantages of 4K laparoscopy in colorectal surgery

Colon surgery Since the rise of the concept of complete mesocolic excision (CME), one of the anatomical focuses in colon cancer surgery is the identification and separation of the mesentery and the complete anatomy of the mesentery. The resolution and fineness of the surgical field of view under the 4K laparoscopic system are greatly increased. Therefore, the boundary line between the membrane and the membrane, which exhibits the characteristics of "yellow and white junction", can be more clearly displayed in 4K; Clear identification can further strengthen the identification ability of the membrane, so that the chief surgeon can perform complete mesentery resection more accurately. Under the 4K high-definition laparoscopic system, it is easier for the surgeon to identify the structures such as the mesocolon and the anterior fascia of the pancreas and duodenum. Ureter and other important anatomical structures, reduce the risk of surgery, improve the safety of surgery and radical oncology. Completion of TME in rectal surgery is critical to patient prognosis during radical rectal tumor resection. In the process of finding and maintaining the sacred plane, the "angel hair"-like structure under 4K laparoscopy is clearer, and the microvascular structure between different anatomical levels is clearer, so it is helpful for us to identify, find, and maintain the correct anatomy. The level provides a more accurate and objective visual basis, so that the principle of laparoscopic total mesorectal resection can be more accurately and reliably implemented. In addition, easily damaged nerve structures such as the epigastric nerve plexus, hypogastric nerve, pelvic nerve plexus, and neurovascular bundles can be displayed more clearly during the dissection of the 4K field of view, which is helpful for intraoperative analysis of these nerves. more precise protection. Compared with the traditional 2D system, the 4K laparoscopic system can more clearly display the structure of the narrow pelvic floor space, and it is more shrewd in the observation of the anatomical structures such as the position of the end point of the mesorectum, the levator hiatus, and the internal and external sphincter space of the anal canal, which is helpful for talents. Precise anatomy of sphincter-preserving surgery for drag rectal cancer. The mirror arm can provide a better surgical field by changing the viewing angle, which is more advantageous than the 3D laparoscope in a small space. Due to the improvement of tissue identification under the 4K field of view, the identification of the pelvic floor nerve is clearer.

(2) The development status of 4K laparoscopic surgery in colorectal surgery Due to the short time to market for 4K laparoscopic surgery equipment, there are currently very limited reports on relevant clinical randomized controlled studies. In 2019, Dunstan et al.'s single-center small case RCT results on the application of 4K and 3D laparoscopic cholecystectomy in cholecystectomy suggested that 4K laparoscopic cholecystectomy may have a shorter time than 3D surgery, but it has not reached statistical significance. There was no significant difference between the two groups in the incidence of complications and intraoperative error rate. The author's team conducted a questionnaire survey on the visual experience in the application of 4K laparoscopic colorectal surgery, and compared the subjective feelings of the surgeons in the operation of 2D laparoscopy, 3D laparoscopy and 4K laparoscopic system. Both the laparoscopic system and the 3D laparoscopic system have advantages over the traditional 2D laparoscopic system; the 4K laparoscopic system can provide better resolution, viewing angle and operation coordination, visual acuity, and color resolution, and the 3D laparoscopic system can provide better resolution. The good depth and intraoperative operation can bring better surgical field to the surgeon than the traditional system.

3. Conclusion The development of the laparoscopic vision platform makes it possible to accurately dissociate the layers, complete the anatomy of the mesentery, and accurately protect the nerves. From the perspective of the development of equipment engineering technology, the safety of laparoscopic colorectal surgery and the curative effect of tumors are improved. It provides the necessary guarantee, which also promotes the laparoscopic colorectal tumor radical surgery towards the direction of precision. As a new laparoscopic surgical equipment platform, it must go through a process of continuous maturation and development. It is believed that the continuous innovation and development of related technologies in minimally invasive surgery will certainly play a huge role in promoting the technological progress of colorectal surgery in the future.