Fruitful first experience with an 8K ultra-high-definition endoscope for laparoscopic colorectal surgery

Harmonized technical standard test methods for quality evaluation of medical fluorescence endoscopic imaging systems

Fluorescence endoscopy technology utilizes a light source of a specific wavelength to excite the fluorescence signals of biological tissues. This capability is extremely valuable for the early detection and precise diagnosis of pathological changes. Identifying a suitable experimental approach and metric for objectively and quantitatively assessing the imaging quality of fluorescence endoscopy is imperative to enhance the image evaluation criteria of fluorescence imaging technology. In this study, we propose a new set of standards for fluorescence endoscopy technology to evaluate the optical performance and image quality of fluorescence imaging objectively and quantitatively. This comprehensive set of standards encompasses fluorescence test models and imaging quality assessment protocols to ensure that the performance of fluorescence endoscopy systems meets the required standards. In addition, it aims to enhance the accuracy and uniformity of the results by standardizing testing procedures. The formulation of pivotal metrics and testing methodologies is anticipated to facilitate direct quantitative comparisons of the performance of fluorescence endoscopy devices. This advancement is expected to foster the harmonization of clinical and preclinical evaluations using fluorescence endoscopy imaging systems, thereby improving diagnostic precision and efficiency.

A multicenter survey of effects and challenges of an 8K ultra-high-definition endoscopy system compared to existing endoscopy systems for endoscopic surgery

INTRODUCTION

8K ultra-high-definition (UHD) images enabling clearer recognition of anatomical structures could contribute to further development of surgical techniques and advanced applications in endoscopic surgery fields. This study aimed to clarify effects and challenges of endoscopic surgery with 8K UHD endoscopy compared to existing endoscopy systems.

METHODS

In this multicenter, cross-sectional, questionnaire survey, data were collected from surgical participants who newly used and observed 8K UHD endoscopy in patients undergoing surgery from February 2020 to February 2021. Survey items included sense of presence, reality, depth perception, visibility of tissue, eyestrain, and degree of satisfaction for operators and observers, and weight, operability, focus adjustment, physical fatigue, eyestrain, and satisfaction for camera assistants. Participants rated each 8K UHD endoscopic surgery on a one-to-five scale (definitively inferior, relatively inferior, equivalent, relatively superior, definitively superior) compared to the existing endoscopy system of each facility.

RESULTS

Overall, questionnaire responses from 139 participants assessing 8K UHD endoscopic surgery were collected from surgeries performed in 46 patients. Respective ratings of operators and observers included sense of presence: "superior or relatively superior", 97.8% and 91.5%; reality: "superior or relatively superior", 76.1% and 72.3%; and visibility of tissue: "superior or relatively superior", 93.5% and 87.2%. Weight was rated as "inferior or relatively inferior" by 73.9% of camera assistants and focus adjustment as "inferior" by 60.9% of them.

CONCLUSIONS

8K UHD endoscopic surgery enabled identification of surgical anatomies more clearly, provided a sense of presence and reality, and might improve educational effect. Technological development is expected to reduce the burden of camera assistants.

The experience of 100 cases of 8K/two-dimensional laparoscopic colorectal surgery - The evaluation of 8K/two-dimensional laparoscopy and how to use it

Background

The resolution of 8K ultra-high-definition imaging technology (7680 × 4320 pixels) is 16-fold higher than the current high-definition technology (1920 × 1080 pixels). 8K/two-dimensional (2D) laparoscopy was clinically available in 2014, but few reports concerning its application have been published. The aim of this study was to evaluate the appropriate methods of usage and problems learned from clinical use of 8K/2D laparoscopy.

Subjects and Methods

The patients were 100 colorectal surgery patients who underwent 8K/2D laparoscopy at Asahikawa Medical University Hospital between November 2018 and March 2021. We evaluated the effectiveness, operating conditions, methods and issues of 8K/2D laparoscopy.

Results

The median age was 68.5 years. The primary disease was malignancy of the left side of the colon and rectum in 92 patients. The right-sided colectomy was performed in five cases, total proctocolectomy of ulcerative colitis was performed in 3 cases. The proper application of 8K/2D laparoscopy can be achieved by adhering to certain tips, such as darkening the operation room and keeping an appropriate distance from the monitor. Regarding intraoperative complications caused by the 8K/2D laparoscope, skin burns due to heat from the tip of the laparoscope were observed in one patient. There were no cases of complications due to the 8K/2D laparoscopy.

Conclusion

8K/2D laparoscopy can be used safely in colorectal surgery. There are still some tips for proper use, such as keeping an appropriate distance to the monitor and darkening the room. However, 8K/2D laparoscopy can provide delicate images and can be used without any operational problems.

Future of Endoscopy in Inflammatory Bowel Diseases (IBDs)

Gastrointestinal (GI) endoscopy has transformed over the years in scope, safety, accuracy, acceptability, and cost effectiveness of the clinical practice. There has been a reduction in the superiority of the endoscopic devices as innovations have taken place and increased the diagnostic values with certain limitations. There are particular difficulties in striking a balance between the development of new technology and the device's acceptance. The wide use of endoscopy for investigating GI lesions and diagnosis has led to an increase in more advanced methods and their broad application. It can simultaneously diagnose pre-malignant and malignant lesions, and newer interventions have made the biopsy specimen uptake possible. In this review article, we focus on the more recent roles, indications, applications, and usage of the innovative methods of endoscopy.

Laparoscopic surgery using 8 K ultra-high-definition technology: Outcomes of a phase II study

INTRODUCTION

Currently, laparoscopic surgery generally relies on 2 K high-definition image quality. The National Cancer Center Hospital, Olympus Corporation, and NHK Engineering System Inc. recently developed a new laparoscopic system with an 8 K ultra-high-definition (UHD) camera that provides images with a high-resolution, wide color range, high frame rate, and high dynamic range. This study aimed to investigate the effectiveness and safety of a new laparoscopic system which uses an 8 K UHD camera system (8K UHD system).

METHODS

This phase II study enrolled 23 patients with colon or rectosigmoid cancer who were indicated for radical resection with laparoscopic colectomy using the 8 K UHD system. The primary endpoint was the proportion of patients with ≥30 mL of intraoperative blood loss.

RESULTS

Of the 23 patients, 22 completed laparoscopic surgery with the 8 K UHD system. One patient was converted to the 2 K high-definition laparoscopic system due to technical difficulties with the 8 K UHD system during surgery. The median amount of intraoperative blood loss was 14 mL (range, 2-71 mL), and number of patients with intraoperative blood loss ≥30 mL was four (17.4%). None of the patients had >100 mL of intraoperative blood loss. No intraoperative complications were noted, and four (17.4%) patients developed postoperative complications. Pathological complete resection was achieved in all patients, and no conversion to open surgery was required.

CONCLUSIONS

Laparoscopic surgery using the 8 K UHD system appears to be both safe and effective. However, further refinements may be necessary to improve usability.

Diagnosis of advanced gastric cancer using image enhancement and autofluorescence imaging systems

INTRODUCTION

The indication of laparoscopic gastrectomy for advanced cases such as serosal invasion or peritoneal dissemination is still controversial. We report the clinical experiences of laparoscopic diagnosis with image enhancement and autofluorescence (AF) systems for laparoscopic gastric cancer surgery.

METHODS

The image enhancement system was introduced to 164 patients who underwent laparoscopic gastric cancer surgery as the AF group. The control group was defined as 165 cases who underwent bright light observation without the image enhancement system. The operative findings were recorded during surgery. All image findings were retrospectively compared with the pathological findings. Furthermore, the relationship between the image and pathological findings for peritoneal dissemination and subserosal invasion was evaluated.

RESULTS

This study included 329 patients, divided into the control group of 165 patients (50.2%) and the AF group of 164 patients (49.8%). There was no statistically significant difference in patient background between the two groups. In seven cases of peritoneal dissemination, AF was positive, and macroscopic abnormal vascularization was detected. The sensitivity, specificity, and positive and negative predictive values were 100%, 99.4%, 87.5%, and 100%, respectively. In 29 cases of serosal invasion, AF was positive, and macroscopic abnormal vascularization was detected. In the detection accuracy of subserosal invasion, the sensitivity, specificity, and positive and negative predictive values were 75.7%, 97.6%, 90.3%, and 93.2%, respectively.

CONCLUSION

The image enhancement with the AF system is useful for the laparoscopic intraoperative diagnosis of serosal invasion and peritoneal dissemination for advanced gastric cancer.

Advances in optical gastrointestinal endoscopy: a technical review

Optical endoscopy is the primary diagnostic and therapeutic tool for management of gastrointestinal (GI) malignancies. Most GI neoplasms arise from precancerous lesions; thus, technical innovations to improve detection and diagnosis of precancerous lesions and early cancers play a pivotal role in improving outcomes. Over the last few decades, the field of GI endoscopy has witnessed enormous and focused efforts to develop and translate accurate, user-friendly, and minimally invasive optical imaging modalities. From a technical point of view, a wide range of novel optical techniques is now available to probe different aspects of light-tissue interaction at macroscopic and microscopic scales, complementing white light endoscopy. Most of these new modalities have been successfully validated and translated to routine clinical practice. Herein, we provide a technical review of the current status of existing and promising new optical endoscopic imaging technologies for GI cancer screening and surveillance. We summarize the underlying principles of light-tissue interaction, the imaging performance at different scales, and highlight what is known about clinical applicability and effectiveness. Furthermore, we discuss recent discovery and translation of novel molecular probes that have shown promise to augment endoscopists' ability to diagnose GI lesions with high specificity. We also review and discuss the role and potential clinical integration of artificial intelligence-based algorithms to provide decision support in real time. Finally, we provide perspectives on future technology development and its potential to transform endoscopic GI cancer detection and diagnosis.

Efficacy of intraoperative ICG fluorescence imaging evaluation for preventing anastomotic leakage after left-sided colon or rectal cancer surgery: a propensity score-matched analysis

BACKGROUND

Intestinal perfusion at the anastomotic site is thought to be one of the most influential risk factors for postoperative anastomotic leakage (AL). We evaluated the efficacy of indocyanine green (ICG) fluorescence imaging at the stump of the proximal colon in left-sided colectomy or rectal resection in terms of decreasing the incidence of AL.

METHODS

Prospectively collected data were retrospectively evaluated. Patients who underwent left-sided colectomy or rectal resection were enrolled (ICG group; n = 197), and patients who had undergone a similar procedure before the ICG group were enrolled from the charts as historical controls (HC group; n = 187). After ICG evaluation, anastomosis was performed where fluorescence was sufficient. The incidence of AL was compared between the ICG and HC groups. Propensity score (PS)-matched data were analyzed to clarify the risk of AL.

RESULTS

AL occurred in 6 patients (3.3%) in the ICG group and 17 (10.7%) in the HC group. ICG evaluation revealed 179 patients with good fluorescence and 18 with poor/none perfusion (9.1%). The transection line was changed in all patients with poor/none fluorescence. Three of these 18 patients developed AL (16.7%), though transection line was changed at which is thought to be good. We hope AL in poor/none fluorescence can be prevented at the same rate of cases with good fluorescence. Actually, the rate of that was significantly higher compared with good fluorescence patients (P = 0.038). 93 patients in each group were compared by PS-matched data analysis, which showed the AL rate in the ICG group was significantly lower than that in the HC group (3.2% vs 10.8%, respectively; P = 0.046).

CONCLUSIONS

Even though this study has limitations of comparison of data prospectively collected and retrospectively analyzed, intraoperative ICG fluorescence imaging evaluation could significantly decrease the incidence of AL.

Mechanism and design of a novel 8K ultra-high-definition video microscope for microsurgery

The practical application of microscopes using 8K ultra-high definition (UHD) technology is progressing. However, due to insufficiencies in factors such as luminous intensity and stereopsis, it has not been possible to achieve sufficient image quality for close observation of submillimeter order microlymphatic anastomosis using a combination of 8K-UHD cameras with a rigid endoscope. We have improved the quality of microsurgery by the introduction of a new heads up 8K-UHD surgical system. Herein, we show the mechanisms of this next-generation technology that makes optical improvements to the electronic image input data, resolving the initial drawback.

We have developed a new 8K-UHD digital microscope system with digital zooming to enable maximum 300X magnification of the surgical field. This system has specific lighting settings for shadows dropped in surgical field to expand the three-dimensional effect while still being a monocular camera. The original mechanism and design enable the increase of the depth of field with optimal angles between the imaging direction and approaching direction towards the surgical field.

Assessment during a pre-clinical trial using rats demonstrated that it is possible to perform microlymphatic anastomosis in a heads-up position with a 70-inch 8K-UHD monitor and the 8K-UHD monocular camera system.

Performing supermicrosurgery is difficult with conventional surgical microscopes. Our results illustrate the application of this new 8K-UHD microscope system to this new field.

Advantage of Using 8K Ultra-High-Definition Television System for Kasai Portoenterostomy for Biliary Atresia

Kasai portoenterostomy (KPE) is currently the first-line treatment for biliary atresia. Many pediatric surgeons have reported that the dissection of the fibrous remnant at the porta hepatis is one of the most important components of this procedure. Furthermore, laparoscopic portoenterostomy is being increasingly used to treat biliary atresia.

An advantage of laparoscopic surgery is that surgeons can more easily identify microbiliary ducts, owing to the magnification. We report the case of a 61-day-old girl on whom we performed an exploratory laparotomy and diagnosed type III biliary atresia using intraoperative cholangiography. For the first time, we performed an open KPE using an 8K ultra-high-definition television system. This allowed us to clearly view the porta hepatis and to successfully perform the portoenterostomy.

A comparison of laparoscopic procedures performed by novice medical students using 8K ultra-high-definition/two-dimensional and 2K high-definition/three-dimensional monitors

PURPOSE

8K Ultra-high-definition (UHD) imaging has been developed in accordance with the progression of imaging technologies. We evaluated laparoscopic procedures performed by novice medical students using 2K/two-dimensional (2D), 2K/three-dimensional (3D) and 8K/2D monitors, with a particular focus on depth perception.

METHODS

Nine medical students were enrolled. They performed two tasks using 2K/2D, 2K/3D and 8K/2D monitors. In Task 1, they were asked to grasp three metal rods with forceps using each hand. In Task 2, they were asked to grasp a metal rod with forceps held in the right hand, pass the metal rod through a metal ring and transfer it to their left hand.

RESULTS

In Task 1, when performed with the dominant hand, the procedures performed using 2K/3D took a significantly shorter time than those performed using 8K/2D (P = 0.04). However, there was no significant difference among the three groups in the time required for procedures performed by the non-dominant hand. In Task 2, the procedure time with 2K/2D was significantly longer than that with 2K/3D or 8K/2D (P = 0.02).

CONCLUSION

2K/3D showed superior utility to 8K/2D for performing forceps procedures using the dominant hand. However, when the movement of both hands was coordinated ("bi-hand coordination"), the laparoscopic procedures were performed almost as deftly with 8K/2D and 2K/3D.

Comparison between the 4K ultra-high definition (UHD) and high definition (HD) endoscopic systems for transoral endoscopic thyroidectomy

Background

The transoral endoscopic thyroidectomy vestibular approach (TOETVA) is the most recently introduced method of minimally invasive thyroid surgery. To our knowledge, no studies have compared TOETVA outcomes using different laparoscopic systems. This study compared outcomes of TOETVA using conventional high definition (HD) and ultra-high definition (UHD) equipment.

Methods

Medical data and surgery videos of 62 patients who randomized to undergo thyroid lobectomy by TOETVA using an HD or UHD system from August 2018 to April 2019 were retrospectively reviewed. Endoscopic procedures were divided into four phases: flap creation to isthmectomy (phase I); strap muscle division to upper pole ligation (phase II); trimming recurrent laryngeal nerve (phase III); and ligation of Berry's ligament to complete resection (phase IV).

Results

Of the 62 patients, 28 underwent TOETVA using an HD device and 34 using a UHD device. The clinical characteristics of the two groups were not different. Mean operating time for lobectomy was similar in the HD and UHD groups (44.19±9.94 versus 43.47±12.19 min, P=0.825). The times required for phases I (15.02±5.33 versus 13.67±5.44 min, P=0.397); II (12.89±2.84 versus 13.17±5.22 min, P=0.816); III (9.85±4.36 versus 9.98±4.55 min, P=0.918); and IV (6.43±3.69 versus 6.65±3.45 min, P=0.840) were also similar in the HD and UHD groups. The numbers of retrieved lymph nodes did not differ significantly in the HD and UHD groups (3.26±2.62 versus 3.45±2.81, P=0.807).

Conclusions

Applying a UHD system in TOETVA resulted in outcomes similar to those observed with a conventional HD system. Operation time tended to be lower, especially for flap dissection, and numbers of harvest lymph nodes tended to be higher in the UHD group. Large-scale studies are needed to assess the advantages of the UHD system.