The role and future of endoscopic imaging systems

Underneath Images and Robots, Looking Deeper into the Pneumoperitoneum: A Narrative Review

Laparoscopy offers numerous advantages over open procedures, minimizing trauma, reducing pain, accelerating recovery, and shortening hospital stays. Despite other technical advancements, pneumoperitoneum insufflation has received little attention, barely evolving since its inception. We explore the impact of pneumoperitoneum on patient outcomes and advocate for a minimally invasive approach that prioritizes peritoneal homeostasis. The nonlinear relationship between intra-abdominal pressure (IAP) and intra-abdominal volume (IAV) is discussed, emphasizing IAP titration to balance physiological effects and surgical workspace. Maintaining IAP below 10 mmHg is generally recommended, but factors such as patient positioning and surgical complexity must be considered. The depth of neuromuscular blockade (NMB) is explored as another variable affecting laparoscopic conditions. While deep NMB appears favorable for surgical stillness, achieving a balance between IAP and NMB depth is crucial. Temperature and humidity management during pneumoperitoneum are crucial for patient safety and optical field quality. Despite the debate over the significance of temperature drop, humidification and the warming of insufflated gas offer benefits in peritoneal homeostasis and visual clarity. In conclusion, there is potential for a paradigm shift in pneumoperitoneum management, with dynamic IAP adjustments and careful control of insufflated gas temperature and humidity to preserve peritoneal homeostasis and improve patient outcomes in minimally invasive surgery.

Fogging of Protective Eyewear in Intensive Care Unit and a Comparative Study of Techniques to Reduce It

Background

Fogging of protective eyewear (PEW) can hinder routine work in the intensive care unit (ICU). The prevalence of fogging impairing vision (FIV) and the technique that reduces fogging have not been evaluated previously.

Methods

After donning personal protective equipment (PPE) with an N95 mask, the healthcare workers (HCWs) sequentially tried plain PEW, soap-coated PEW, PEW worn at a distance over the PPE hood, and the use of tape over a mask. The vision (distant and near) was checked before wearing PEW and with each technique. The prevalence of fogging and FIV, that is, change in vision in either eye was estimated and compared among various techniques. Mixed-effects logistic regression was used to analyze factors affecting fogging and to compare techniques. Room temperature, room humidity, and lens temperature were measured during the study.

Results

A total of 125 HCWs participated (151 observations) and the prevalence of FIV was 66.7%. The fogging of PEW, as well as the extent of PEW fogging, was least with soap coating followed by a mask with tape and goggles worn at a distance. The FIV was significantly lesser only with the mask with tape with an odds ratio (OR) [confidence interval CI)] of 0.45 (0.25-0.82). The prevalence of fogging while at work in the COVID ICU was 38%.

Conclusion

The prevalence of FIV is 66%. Application of tape over the mask can avoid disturbances in vision best. Soap coating of the PEW and PEW worn at distance from the eyes are potential alternatives.

How to cite this article

Ravisankar NP, D'Silva CS, Varma MMKG, Sudarsan TI, Sampath S, Thomas T, et al. Fogging of Protective Eyewear in Intensive Care Unit and a Comparative Study of Techniques to Reduce It. Indian J Crit Care Med 2023;27(1):32-37.

Prospective randomized controlled trial on comparison of standard CO2 pressure pneumoperitoneum insufflator versus AirSeal®

Background

AirSeal® is a valve-free insufflation system that enables a stable pneumoperitoneum with continuous smoke evacuation and CO₂ recirculation during laparoscopic surgery. Comparative evidence on the use of AirSeal® and standard CO₂ insufflator in laparoscopic general surgery procedures is scarce. The aim of this study was to compare surgical outcomes between AirSeal® and standard CO₂ insufflators in patients undergoing the most frequently performed laparoscopic procedures.

Methods

One hundred and ninety-eight patients undergoing elective laparoscopic cholecystectomy, colorectal surgery and hernia repair were randomized to either AirSeal® (group A) or standard pressure CO₂ insufflator (group S). The primary endpoints were operative time and level of postoperative shoulder tip pain (Visual Analog Scale). Secondary outcomes included Clavien–Dindo grade complications, surgical side effect and length of hospital stay.

Results

Patients were randomized to either group A (n = 101) or group S (n = 97) and were analyzed by intention-to-treat. There was no significant difference in mean operative time between the groups (median [IQR]; 71 min [56–94] in group A vs. 69 min [52–93] in group S; p = 0.434). Shoulder tip pain levels were significantly lower in group S (VAS 0 [0–3] in group S vs. 2 [0–4] in group A; p = 0.001). There was no significant difference in complications, surgical side effects (subcutaneous emphysema was not observed in any group) and length of hospital stay.

Conclusion

This randomized controlled trial showed that using the AirSeal® system did not reduce operative time and was associated with a higher postoperative shoulder tip pain compared to standard CO₂ insufflator for short elective surgeries.

ClinicalTrials.gov (NCT01740011).

Robotic Endoscopy

Endoscopes extend the eyes of the physician into the patient's body. They are widely used in gastrointestinal (GI) diagnostics and minimally invasive surgery. Endoscopes can be classified into 3 types: rigid, flexible, and capsule endoscopes. Rigid and flexible endoscopes are traditionally held and manipulated by the physician to visualize the region of interest, while capsule endoscopes move passively along with the GI peristalsis. With the advancement of technology, robotic endoscopy has been increasingly developed and accepted. In this work, robotic endoscopy from 3 categories (robot-assisted rigid endoscopy, robot-assisted flexible endoscopy, and active GI endoscopy including active flexible colonoscopy and active capsule endoscopy) is reviewed by PubMed search with the criteria ('Robotics' OR 'Robot') and ('Endoscopy' OR 'Endoscope').

Advances in laparoscopic surgery in urology

In the past 10 years, laparoscopy has been challenged by robotic surgery; nevertheless, laparoscopic techniques are subject to continuous change. Ultrahigh definition is the next development in video technology, it delivers fourfold more detail than full high definition resulting in improved fine detail, increased texture, and an almost photographic emulsion of smoothness of the image. New 4K ultrahigh-definition technology might remove the current need for the use of polarized glasses. New devices for laparoscopy include advanced sealing devices, instruments with six degrees of freedom, ergonomic platforms with armrests and a chest support, and camera holders. A manually manipulated robot-like device is still at the experimental stage. Robot-assisted surgery has substantially revolutionized laparoscopy, increasing its distribution; however, robot-assisted surgery is associated with considerable costs. All technical improvements of laparoscopic surgery are extremely valuable to further simplify the use of classical laparoscopy.

Virtual digital defogging technology improves laparoscopic imaging quality

BACKGROUND

The aim of this study was to evaluate the effects of a newly developed digital defogging (DD) system on imaging quality in laparoscopic surgery. Lens fogging instantly degrades image quality and interrupts the flow of surgical maneuvers during laparoscopic surgery. To address this problem, we developed a DD system based on the dark channel prior.

METHODS

Two hundred patients with gallstones or right colon cancer were enrolled in this study. Of the 100 patients who underwent laparoscopic cholecystectomy, 50 used a regular monitor (group A) while the other 50 used a DD monitor (group B). Of the 100 patients who underwent laparoscopic colectomy, the regular monitor was used for 50 (group C) and the DD monitor was used for the other 50 (group D). The clarity of images, the ratio of lens-cleaned time to operative time, and the subjective anxiety of the surgeons were evaluated for all cases.

RESULTS

There were significant differences (P < .05) in the clarity of images between groups C (2.68 ± 1.19) and D (1.98 ± 1.00) and the ratio of lens-cleaned time to operative time between groups C (5.22 ± 0.89) and D (4.14 ± 0.85). Moreover, the DD system significantly reduced the subjective anxiety of the surgeons (P < .001) in colectomy procedures, compared with the regular monitor.

CONCLUSIONS

The DD system can export a dynamic stable image to the monitor during laparoscopic surgery, which can result in shorter operative time with less surgeon anxiety.

Evaluating the effect of three-dimensional visualization on force application and performance time during robotics-assisted mitral valve repair

OBJECTIVE

The purpose of this study was to determine the effect of three-dimensional (3D) binocular, stereoscopic, and two-dimensional (2D) monocular visualization on robotics-assisted mitral valve annuloplasty versus conventional techniques in an ex vivo animal model. In addition, we sought to determine whether these effects were consistent between novices and experts in robotics-assisted cardiac surgery.

METHODS

A cardiac surgery test-bed was constructed to measure forces applied during mitral valve annuloplasty. Sutures were passed through the porcine mitral valve annulus by the participants with different levels of experience in robotics-assisted surgery and tied in place using both robotics-assisted and conventional surgery techniques.

RESULTS

The mean time for both the experts and the novices using 3D visualization was significantly less than that required using 2D vision (P < 0.001). However, there was no significant difference in the maximum force applied by the novices to the mitral valve during suturing (P = 0.7) and suture tying (P = 0.6) using either 2D or 3D visualization. The mean time required and forces applied by both the experts and the novices were significantly less using the conventional surgical technique than when using the robotic system with either 2D or 3D vision (P < 0.001).

CONCLUSIONS

Despite high-quality binocular images, both the experts and the novices applied significantly more force to the cardiac tissue during 3D robotics-assisted mitral valve annuloplasty than during conventional open mitral valve annuloplasty. This finding suggests that 3D visualization does not fully compensate for the absence of haptic feedback in robotics-assisted cardiac surgery.

A review of optical NDT technologies

Optical non-destructive testing (NDT) has gained more and more attention in recent years, mainly because of its non-destructive imaging characteristics with high precision and sensitivity. This paper provides a review of the main optical NDT technologies, including fibre optics, electronic speckle, infrared thermography, endoscopic and terahertz technology. Among them, fibre optics features easy integration and embedding, electronic speckle focuses on whole-field high precision detection, infrared thermography has unique advantages for tests of combined materials, endoscopic technology provides images of the internal surface of the object directly, and terahertz technology opens a new direction of internal NDT because of its excellent penetration capability to most of non-metallic materials. Typical engineering applications of these technologies are illustrated, with a brief introduction of the history and discussion of recent progress.

Alternative agents to prevent fogging in head and neck endoscopy

BACKGROUND

The essential factor for diagnosis and treatment of diseases in head and neck endoscopy is the visibility of the image. An anti-fogging agent can reduce this problem by minimizing surface tension to prevent the condensation of water in the form of small droplets on a surface. There is no report on the use of hibiscrub(®) or baby shampoo to reduce fogging in the literature. The objective of this study was to compare the efficacy between commercial anti-fogging agent, hibiscrub(®) and baby shampoo to reduce fogging for the use in head and neck endoscopy.

METHODS

The study was conducted at the Department of Otorhinolaryngology, Faculty of Medicine, Khon Kaen University in August 2010. Commercial anti-fogging agent, baby shampoo and hibiscrub(®) were applied on rigid endoscope lens before putting them into a mist generator. The images were taken at baseline, 15 seconds, 30 seconds and 1 minute. The images' identifiers were removed before they were sent to two evaluators. A visual analogue scale (VAS) was used to rate the image quality from 0 to 10.

RESULTS

The difference in mean VAS score between anti-fogging agent, baby shampoo and hibiscrub(®) versus no agent were 5.46, 4.45 and 2.1 respectively. The commercial anti-fogging agent and baby shampoo had most protective benefit and performed significantly better than no agent (P = 0.05).

CONCLUSIONS

Baby shampoo is an effective agent to prevent fogging during head and neck endoscopy and compares favourably with commercial anti-fogging agent.

System solutions for the integration of devices in the OR

The technical complexity of the surgical arena, as well as of related specialised fields, has increased significantly. A look at the current situation in various surgical disciplines shows that, despite existing high-tech equipment, the operating room (OR) can still not be considered an ergonomic and optimised work environment. Industrial suppliers have integrated new procedures and techniques into surgical disciplines, often without consulting other manufacturers and without establishing or implementing appropriate standards. This paper describes the development of an integrated workstation for the OR and its related technical and clinical aspects, e.g. process analysis, system integration, standardisation, image processing, user interfaces, communication protocols (CANopen, DICOM) and networking. The first introduction of the prototype to our clinical partners has confirmed that the implementation of an optimised system workstation in the OR results in improved processes. The standardised and simplified user guidance leads to improved ergonomy. The selected communication standard between the subsystems of the diverse industrial suppliers gives the user more flexibility in configuring the individual OR system. Intensive collaboration between industry and clinical partners will continue to be vital for the further development of such complex system workstations in medicine.

Laparoscopic lens fogging: a review of etiology and methods to maintain a clear visual field

Laparoscopic surgical procedures are becoming common across surgical specialties, including urology. Maintaining a clear field of vision is paramount in such procedures not only for safety by preventing inadvertent injury, but also to improve precision and reduce operative time. Laparoscopic lens fogging (LLF) is a major impediment to a clear visual field during laparoscopy and is caused by condensation as well as particulate debris, blood, and smoke accumulation on the scope lens. Despite many available techniques to improve vision during laparoscopy, available data on etiology and methods to improve vision have only sporadically been considered in the literature. The objective of this review was to summarize current literature on the etiology of LLF and other causes of poor vision during laparoscopy and also review the current approaches for minimizing or reducing such events. In summary, although the etiology of LLF is well understood, that is, temperature and humidity differences, the methods to reduce its occurrence lack significant data. Of those methods that are often espoused, most are not supported in the literature, such as warmed and humidified insufflation gas, or simply lack data, such as antifogging solutions.

Telepresence surgery: first experiences with laparoscopic radical prostatectomy

The concept of an intelligent steerable surgical instrument system has been described by various authors. Since 1998, telesurgical minimally invasive procedures have been performed with the da Vinci system, mainly for cardiac bypass surgery. We present our initial experience using the device for robot-assisted laparoscopic radical prostatectomy. The intuitive surgical system consists of two main components: the surgeon's viewing and control console with 3D-imaging, and the surgical arm unit that positions and manoeuvres detachable surgical instruments. These instruments are introduced via two 8 mm trocars and allow movements in all six degrees of freedom (DoF). The surgeon performs the procedure while seated at the console holding specially designed instruments. Highly specialised computer software and mechanics transmit the surgeon's hand movements exactly to the microsurgical movements of the manipulators at the operative site. The system used is a W-shaped five trocar arrangement, with the robot's arms at the lateral trocars (8 mm) and two assistant trocars medially (10 mm). A sixth trocar was used in the right suprapubic area for retraction of the gland (Foley catheter). The left assistant used different instruments, such as bipolar forceps, Ultracision, and Endoclip, wheras the right assistant mainly used the suction&#150;irrigation device. The Intuitive System was attached after trocar placement and exposure of Retzius' space. We treated six patients (two pT2, four pT3, median Gleason score 6). The operating room time averaged 315 (range 242&#150;480) min, including pelvic lymph-node dissection. No intra-operative complications occured, one patient required transfusions. There were no positive margins, median catheter time was 5 days. Three patients were completely continent after 1 month. Telerobotic laparoscopic radical prostatectomy is feasible. There is a learning curve with the device, mainly due to the magnification, 3D image and lack of tactile feedback. However, the experienced surgeon can become familiar with the device after a short time. There is still a need for further development of instruments for urological procedures.

Robotics and telesurgery – an update on their position in laparoscopic radical prostatectomy

Laparoscopy is handicapped by the reduction of the range of motion from six to only four degrees of freedom. In complicated cases (i.e. radical prostatectomy), there is often a crossing of the hands of surgeon and assistant. Finally, standard laparoscopes allow only 2D-vision. This has a major impact on technically difficult reconstructive procedures such as laparoscopic radical prostatectomy. Solutions include the understanding of the geometry of laparoscopy, but also newly developed surgical robots. During the last five years, there has been an increasing development and experience with robotics in urology. This article reviews the actual results focussing on the benefits and problems of robotics in laparoscopic radical prostatectomy. Own experiences with robot-assisted surgery include more than 1200 laparoscopic radical prostatectomies using a voice-controlled camera-arm (AESOP) as well as six telesurgical interventions with the da Vinci-system. Substantial experimental studies have been performed focussing on the geometry of laparoscopy and new training concepts such as perfused pelvitrainers and models for simulation of urethrovesical anastomosis. The recent literature on robotics in urology has been reviewed based on a MEDLINE/PUBMED research. The geometry of laparoscopy includes the angles between the instruments which have to be in a range of 25 degrees to 45 degrees ; the angles between the instrument and the working plane that should not exceed 55 degrees ; and the bi-planar angle between the shaft of the needle holder and the needle which has to be adapted according to the anatomical situation in range of 90 degrees to 110 degrees . 3-D-systems have not yet proved to be effective due to handling problems such as shutter glasses, video helmets or reduced brightness. At the moment, there are only two robotic surgical systems (AESOP, da Vinci) in clinical use, of which only the da Vinci provides stereovision and all six degrees of freedom (DOF). To date, more than 3000 laparoscopic radical prostatectomies have been performed worldwide at 92 centres with this system. The main advantage of the system represents the translation of open surgical skills to laparoscopy. Despite recent development of basic tools (e.g. bipolar forceps) for the da Vinci robot, investment and maintenance costs still represent the major problem of the device. Additionally, the device does not provide any haptic sense (i.e. tactile feedback). Robotic surgery represents a turning point of surgical research. However, broad use of robotic systems is limited mainly because of the high investment and running costs. Interestingly, more than in the field of cardiac surgery, there seems to be a need for telemanipulators in urology, mainly to reduce the learning curve of standard laparoscopy. However, new training concepts used in combination with mono-tasking computerized robots (AESOP) have proved their efficacy associated with a significant cost reduction.

Mechanical Simulators for Training for Laparoscopic Surgery in Urology

BACKGROUND AND PURPOSE

The introduction of laparoscopic surgery into urology has led to new training concepts differing significantly from previous concepts of training for open surgery. This paper focuses on the type and importance of mechanical simulators in laparoscopic training.

MATERIALS AND METHODS

On the basis of our own studies and experience with the development of various concepts of laparoscopic training, including different modules (i.e., Pelvi-trainer, animal models, clinical mentoring) since 1991, we reviewed the current literature concerning all types of simulators. We focused on training for laparoscopic ablative and reconstructive surgery using mechanical simulators.

RESULTS

The principle of a mechanical simulator (i.e., a box with the possibility of trocar insertion) has not changed during the last decade. However, the types of Pelvi-trainers and the models used inside have been improved significantly. According to the task of the simulator, various sophisticated models have been developed, including standardized phantoms, animal organs, and even perfused segments of porcine organs. For laparoscopic suturing, various step-by-step training concepts have been presented. These can be used for determination of the ability of a physician with an interest in laparoscopic surgery, but also to classify the training status of a laparosopic surgeon.

CONCLUSIONS

Training in laparoscopic surgery has become an important topic, not only in learning a procedure, but also in maintaining skills and preparing for the management of complications. For these purposes, mechanical simulators will definitely play an important role in the future.

New Technology for Imaging and Documenting Urologic Procedures

Recent advances in fiber optics and digital technology have dramatically improved the ability of the urologic surgeon to accurately image and document endoscopic and laparoscopic procedures. In addition, the development of digital endoscopes has expanded the armamentarium of the endoscopic surgeon greatly. Finally, new virtual reality technology has allowed increased visualization during surgery and provides excellent training for surgeons. This article details new imaging and documentation technology currently utilized during urologic procedures.

Advances in video and imaging in ureteroscopy

Advances in image processing and display technologies, such as digital imaging, HDTV, and virtual reality, will ultimately allow integration of endoscopic imaging with diagnosis and therapy during ureteroscopic procedures. Further improvements in simulation technology and telemedicine should improve surgical training and greatly benefit patient care.

The benefits of stereoscopic vision in robotic-assisted performance on bench models

BACKGROUND

Previous studies have failed to establish clear advantages for the use of stereoscopic visualization systems in minimal-access surgery. The aim of this study was to objectively assess whether stereoscopic visualization improves performance on bench models using the da Vinci robotic system.

METHODS

Eleven surgeons carried out a series of four tasks. Positional data streamed from the da Vinci system was analyzed by means of a previously validated custom-designed software-package. An independent blinded observer scored errors. Statistical analysis included the Wilcoxon signed rank test. A p < 0.05 was deemed significant.

RESULTS

We found significant improvements in all tasks and for all parameters (p < 0.05). In addition, a significantly lower number of errors was scored using the stereoscopic mode as compared to the standard two-dimensional image (p < 0.001).

CONCLUSION

Robotic-assisted performance on bench models is more efficient and accurate using stereoscopic visualization.

Robotic and telesurgery: will they change our future?

In urology, at the end of the last millennium, there was an increasing use of computerized technology, extracorporeal shock wave lithotripsy, microwave therapy and high-energy focused ultrasound. However, experience with manipulating robots in urological surgery is still very limited. Laparoscopic surgery is handicapped by a reduction of the range of motion because of the fixed trocar position. The da Vinci system is the first surgical system to address all these problems adequately. The system consists of two main components: the surgeon's viewing and control console with three-dimensional imaging and the surgical arm unit that positions and manoeuvres detachable surgical instruments. The surgeon performs the procedure seated at the console holding specially designed instruments. Telerobotic laparoscopic radical prostatectomy provides advantages such as stereovision, dexterity and tremor filtering, but there is a learning curve with the device, mainly because of the magnification, the three-dimensional image and the lack of tactile feedback. However, after only a short period of time, the experienced surgeon is able to become familiar with the device. The impact of robotics in urological surgery is therefore very promising, and we are convinced that it will totally change the future of urological surgery.