Comparative Optics of the Surgical Microscope and Rigid Endoscopes in Neurosurgery.

This chapter is intended to provide a brief overview of the optics of surgical microscopes and rigid endoscopes, with the aim of providing the reader with the principles dictating the nature of surgical visualization when either of the visual control systems is used. It is not by any means geared toward elaborating on the detailed optical physics of these systems, which is beyond the scope and objective of this chapter.

Potential effects of aerosol generation and transmission during bedside endoscope cleaning.

Airborne transmission is among the most frequent types of nosocomial infection. Recent years have witnessed frequent outbreaks of airborne diseases, such as severe acute respiratory syndrome (SARS) in 2002, Middle East respiratory syndrome (MERS) in 2012, and coronavirus disease 2019 (COVID-19), with the latter being on the rampage since the end of 2019 and bringing the effect of aerosols on health back to the fore (Gralton et al., 2011; Wang et al., 2021). An increasing number of studies have shown that certain highly transmissible pathogens can maintain long-term stability and efficiently spread through aerosols (Leung, 2021; Lv et al., 2021). As reported previously, influenza viruses that can spread efficiently through aerosols remain stable for a longer period compared to those that cannot. The World Health Organization (WHO) has stated that aerosol-generating procedures (AGPs) play an important role in aerosol transmission in hospitals (Calderwood et al., 2021). AGPs, referring to medical procedures that produce aerosols, including dental procedures, endotracheal intubation, sputum aspiration, and laparoscopic surgeries, have been reported to be significantly associated with an increased risk of nosocomial infection among medical personnel (Hamilton, 2021).

[Therapeutic effect of ß-tricalcium phosphate in mastoid cavity obliterationunder endoscope].

Objective:To investigate the therapeutic effect of ß-tricalcium phosphate in mastoid cavity obliteration for middle ear cholesteatoma under endoscope. Methods:Sixty patients with middle ear cholesteatoma admitted to our department from September 2021 to March 2022 were included in this study. The observation group（n=30） received ß-tricalcium phosphate during mastoid cavity obliteration. The control group（n=30） received autologous tissue during mastoid cavity obliteration. Pure tone audiometry was performed before surgery and after surgery in both groups, and the air conduction thresholds of 500, 1 000, 2 000 and 4 000 Hz were recorded. The external acoustic meatus cross-sectional area within 1 cm of the external acoustic meatus opening was measured during the operation and after the operation. The differences of postoperative ear drying time, hearing change and mastoid cavity healing were compared between the two groups. Results:The duration of postoperative dry ear in the observation group was 2-14 weeks, with an average of （9.4±2.7） weeks, while that in the control group was 4-26 weeks, with an average of（16.0±5.7） weeks. The difference in dry ear time between the two groups was statistically significant（P<0.05）. In the observation group, the threshold change was -19-27 dB, with an average of（6.4±10.7） dB, and in the control group, the threshold change was -9-17 dB, with an average of （4.7±7.1） dB. There was no significant difference in hearing change between the two groups（P>0.05）. In the observation group, the cross-sectional area of 1 cm inside the ear canal opening was -5.9-8.2 mm², with an average of （-0.6±2.6） mm², and in the control group, the cross-sectional area of 1 cm inside the ear canal opening was -5.5-5.2 mm², with an average of （-0.4±2.3） mm². There was no significant difference in intraoperative cavity changes between the two groups（P>0.05）. Conclusion:The application of ß-tricalcium phosphate to fill the mastoid cavity during the operation of endoscopic middle ear cholesteatoma has no adverse effect on the hearing of patients, can shorten the postoperative dry ear time, and results in good postoperative healing, which is worth promoting.

A Multidisciplinary Approach to Enhancing Sterilization Processes for Pleuravideoscopes in a Pulmonary Clinic.

PURPOSE/OBJECTIVES: The Centers for Disease Control and Prevention has highlighted the strong association between healthcare-associated infections and the reprocessing of flexible endoscopes. This process improvement project provided an evidence-based workflow analysis of pleuravideoscope reprocessing to validate and implement safe practices in the pulmonary clinic and sterile processing department. DESCRIPTION OF THE PROJECT/PROGRAM: A multidisciplinary team created an audit tool to complete infection control risk assessment using Lean Six Sigma methodology. OUTCOME: The risk assessment identified gaps in clinical practice, prompting corrective measures using a shared decision-making approach. The organization updated standard operating procedures, provided training and competency assessments, and purchased single-use pleuravideoscopes. These initiatives addressed the deficiencies and reinforced a culture of continuous process improvement and patient safety. CONCLUSION: Multidisciplinary teams should perform comprehensive reviews of facility processes and assess the risks related to infection control to identify optimal pleuravideoscope workflows for the healthcare institution. The involvement of a clinical nurse specialist is advantageous, as they possess the expertise necessary to facilitate collaborative efforts among team members spanning various departments. By leveraging the insights and skills of diverse professionals, healthcare organizations can optimize their reprocessing programs and enhance patient safety.

An Actuated Variable-View Rigid Scope System to Assist Visualization in Diagnostic Procedures.

OBJECTIVE: Variable-view rigid scopes offer advantages compared to traditional angled laparoscopes for examining a diagnostic site. However, altering the scope's view requires a high level of dexterity and understanding of spatial orientation. This requires an intuitive mechanism to allow an operator to easily understand the anatomical surroundings and smoothly adjust the scope's focus during diagnosis. To address this challenge, the objective of this work is to develop a mechanized arm that assists in visualization using variable-view rigid scopes during diagnostic procedures. METHODS: A system with a mechanized arm to maneuver a variable-view rigid scope (EndoCAMeleon - Karl Storz) was developed. A user study was conducted to assess the ability of the proposed mechanized arm for diagnosis in a preclinical navigation task and a simulated cystoscopy procedure. RESULTS: The mechanized arm performed significantly better than direct maneuvering of the rigid scope. In the preclinical navigation task, it reduced the percentage of time the scope's focus shifted outside a predefined track. Similarly, for simulated cystoscopy procedure, it reduced the duration and the perceived workload. CONCLUSION: The proposed mechanized arm enhances the operator's ability to accurately maneuver a variable-view rigid scope and reduces the effort in performing diagnostic procedures.Clinical and Translational Impact Statement: The preclinical research introduces a mechanized arm to intuitively maneuver a variable-view rigid scope during diagnostic procedures, while minimizing the mental and physical workload to the operator.

Eye-controlled endoscopy - a benchtop trial of a novel robotic steering platform - iGAZE2.

The endoscopic control system has remained similar in design for many decades The remit of advanced therapeutic endoscopy continues to expand requiring precision control and high cognitive workloads. Robotic systems are emerging, but all still require bimanual control and expensive and large new systems. Eye tracking is an exciting area that can be used as an endoscope control system. This is a study to establish the feasibility of an eye-controlled endoscope and compare its performance and cognitive demand to use of a conventional endoscope. An eye gaze-control system consisting of eye-tracking glasses, customised software and a small motor unit was built and attached to a conventional endoscope. Twelve non-endoscopists used both the eye gaze system and a conventional endoscope to complete a benchtop task in a simulated oesophagus and stomach. Completion of tasks was timed. Subjective feedback was collected from each participant on task load using the NASA Task Load Index. Participants were significantly quicker completing the task using iGAZE2 vs a conventional endoscope (65.02 ± 16.34s vs 104.21 ± 51.31s, p = 0.013) Participants were also significantly quicker completing retroflexion using iGAZE2 vs a conventional endoscope (8.48 ± 3.08 vs 11.38 ± 5.36s, p = 0.036). Participants reported a significantly lower workload (raw NASA-TLX score) when using iGAZE2 vs the conventional endoscope (152.1 ± 63.4 vs 319.6 ± 81.6, p = 0.0001) (Fig. 7). Users found iGAZE2 to have a significantly lower temporal demand, mental demand, effort, mental demand, physical demand, and frustration level. The eye gaze system is an exciting, small, and retrofittable system to any endoscope. The system shows exciting potential as a novel endoscopic control system with a significantly lower workload and better performance in novices suggesting a more intuitive control system.

The Usefulness of the 3.1-mm-diameter 4K Rigid Endoscope for Intracerebral Hematoma Evacuation.

The indication for surgical intervention in spontaneous intracerebral hemorrhage remains controversial. Although many clinical trials have failed to demonstrate its efficacy over medical treatment, less invasive endoscopic treatment is expected to demonstrate its superiority. A novel endoscopic system for hematoma removal consisting of a 3.1-mm-diameter 4K high-resolution rigid endoscope was used.The system was used in eight cases of spontaneous intracerebral hemorrhage. It provided improved maneuverability of the surgical instrument while maintaining satisfactory image quality. The surgical goal was achieved in all cases without any complications, including perioperative rebleeding.Endoscopic hematoma removal using the 3.1 mm high-resolution endoscope is an alternative minimally invasive approach to spontaneous intracerebral hemorrhage with improved reliability.

Unveiling the importance of the endoscope in the sealing of the superior canal dehiscence syndrome, how we do it.

The superior canal dehiscence syndrome is a pathology that affects the arcuate eminence creating a "third window" between the inner ear and the middle fossa. This condition can lead to symptoms such as hearing loss, autophony, or sound-induced vertigo. Traditionally, surgical treatment has been performed by microscope-assisted temporal craniotomy, but when the dehiscence is in the medial part of the arcuate eminence the bone defect may not be seen. We present case series treated at our institution diagnosed of superior canal dehiscence syndrome involving the medial slope of the arcuate eminence. During surgery, the bone defect could not be visible with traditional microscopic techniques. Nonetheless, by introducing the endoscope with the 0º and 30º optics, the dehiscence could be clearly observed and treated correctly. Our results show a clinical improvement without side effects or complications in the patients undergoing this technique. Endoscope-assisted surgery is a safe procedure and provides a better visualization of medial defects.

Endoscope sampling and culturing methods.

BACKGROUND: Contamination rates reported in the literature for patient-ready flexible endoscopes vary from 0.4% to 49%. Unfortunately, the comparison and interpretation of these results is almost impossible since several factors including sampling and culturing methods, target levels for contamination, or definition of indicator micro-organisms vary widely from one study to the other. AIM: To compare the efficacy of six duodenoscope sampling and culturing methods by means of extraction efficacy comparison, while at the same time identifying key parameters that provide optimal microbial recovery. METHODS: The duodenoscope sample extraction efficacy of each method was assessed using the repetitive recovery method described in ISO 11737-1: 2018. FINDINGS: Mean overall bioburden extraction efficacy varied from 1% for the Australian method to 39% for the French one. The lowest endoscope sample extraction efficacy was associated with the absence of any neutralizer, friction, or tensioactive agent, and when only a small portion of the sampling solution collected was inoculated on to culture media. The efficacy of the sampling and culturing methods also varied according to the nature of micro-organisms present in the endoscope, and the time between sampling and culturing. CONCLUSION: This study supports the need for a harmonized and standardized sampling and culturing method for flexible endoscopes.

Endoscopic Dilatation with Ultrathin Endoscope Assisted Method for Esophageal and Pyloric Stricture related Corrosive Injury: 4 Years Case Series Study.

Corrosive injuries (CI) become medical problems related complications include esophageal, pyloric stricture and squamous cell carcinoma, physical and quality of life. Endoscopic (ED) dilatation is primary therapy. The ultrathin endoscope-assisted method is potentially safe and useful in avoiding technical failure. Describe clinical outcomes of ED ED-related CI including successful, refractory, recurrent, and complications-related procedures. Case series study of esophageal and/or pyloric stricture patients after CI who underwent dilatation at Soetomo General Hospital (July 2018 - July 2022). One - biweekly ED using Through The Scope (TTS) balloon or Savary Bougie dilator. The target diameter is 14mm. Fifteen patients with stricture-related CI. Eleven patients underwent ED with a total of 73 procedures. Mean age 31,45 years, predominantly male patients (6), suicide attempt (7), acid agent (9), located at esophagus (3), pylorus (3), or both (5). Number of esophageal dilatation to achieve the target of 14 mm was 1-2 and 2-15 procedures for simple and complex stricture. Five esophageal strictures were successfully dilated but 2 patients were recurrent and 3 cases were refractory to ED. Pyloric dilatation resulted in a lower success rate. Recurrent and refractory cases were 5 and 3 patients respectively. ED with ultrathin endoscope method is useful for traversing guidewire during ED. Ongoing inflammation and fibrosis were linked to recurrent and refractory stricture.

One-hole split endoscope versus unilateral biportal endoscopy for lumbar spinal stenosis: a retrospective propensity score study.

BACKGROUND: The one-hole split endoscopy (OSE) was first proposed and clinically applied in China in 2019. The aim of this study was to compare the clinical efficacy of one-hole split endoscopy (OSE) and unilateral biportal endoscopy (UBE) for treating lumbar spinal stenosis (LSS). METHODS: One hundred sixty patients with LSS who met the inclusion from November 2020 to August 2022 were analyzed and divided into OSE and UBE groups. The propensity score matching (PSM) method was used to adjust the imbalanced confounding variables between the two groups. After matching, surgical outcomes were recorded, and clinical data, including functional scores and imaging findings, were compared. Functional scores included the visual analog scale of leg pain (VAS-LP) and back pain (VAS-BP), the Japanese Orthopedic Association score (JOA), and the Oswestry Disability Index (ODI). Imaging data included dural sac cross-sectional area (DCSA), lumbar range of motion (ROM), and sagittal translation (ST). RESULTS: After PSM, 104 LSS patients were included in the study, and all covariates were well-balanced between the two groups. Among the matched patients, the OSE showed advantages over the UBE regarding operative time (62.42 ± 4.86 vs. 68.96 ± 4.56) and incision length (2.30 ± 0.14 vs. 2.70 ± 0.15) (P < 0.001). However, differences between the two groups in intraoperative blood loss, hospital length of stay, and complication rates were not statistically significant (P > 0.05). There was no statistically significant difference regarding VAS-BP, VAS-LP, JOA, and ODI between the two groups (P > 0.05). However, all clinical and functional scores significantly improved postoperatively (P < 0.05). Postoperative DCSA of both groups was significantly found to be improved (P < 0.05), ROM and ST remained within the normal range, and no cases of lumbar instability were recorded. According to the modified MacNab criteria, the excellent and good rates in the OSE and UBE groups were 94.23% and 90.38%, respectively, with no statistically significant difference (P = 0.713). CONCLUSION: OSE is an alternative technique to UBE for the treatment of LSS, with similar satisfactory clinical outcomes, shorter operative time, and smaller incision length. Further studies are needed for long-term efficacy.

Thin flexible photoacoustic endoscopic probe with a distal-driven micro-step motor for pump-probe-based high-specific molecular imaging.

Conventional photoacoustic endoscopy (PAE) is mostly for structural imaging, and its molecular imaging ability is quite limited. In this work, we address this issue and present the development of a flexible acoustic-resolution-based photoacoustic endoscopic (AR-PAE) probe with an outer diameter of 8 mm. This probe is driven by a micro-step motor at the distal end, enabling flexible and precise angular step control to synchronize with the optical parametric oscillator (OPO) lasers. This probe retains the high spatial resolution, high penetration depth, and spectroscopic imaging ability of conventional AR-PAE. Moreover, it is capable for background-free high-specific photoacoustic molecular imaging with a novel pump-probe detection technique, as demonstrated by the distribution visualizing of the FDA approved contrast agent methylene blue (MB) in an ex-vivo pig ileum. This proposed method represents an important technical advancement in multimodal PAE, and can potentially make considerable contributions across various biomedical fields.

Autonomous Magnetic Navigation in Endoscopic Image Mosaics.

Endoscopes navigate within the human body to observe anatomical structures with minimal invasiveness. A major shortcoming of their use is their narrow field-of-view during navigation in large, hollow anatomical regions. Mosaics of endoscopic images can provide surgeons with a map of the tool's environment. This would facilitate procedures, improve their efficiency, and potentially generate better patient outcomes. The emergence of magnetically steered endoscopes opens the way to safer procedures and creates an opportunity to provide robotic assistance both in the generation of the mosaic map and in navigation within this map. This paper proposes methods to autonomously navigate magnetic endoscopes to 1) generate endoscopic image mosaics and 2) use these mosaics as user interfaces to navigate throughout the explored area. These are the first strategies, which allow autonomous magnetic navigation in large, hollow organs during minimally invasive surgeries. The feasibility of these methods is demonstrated experimentally both in vitro and ex vivo in the context of the treatment of twin-to-twin transfusion syndrome. This minimally invasive procedure is performed in utero and necessitates coagulating shared vessels of twin fetuses on the placenta. A mosaic of the vasculature in combination with autonomous navigation has the potential to significantly facilitate this challenging surgery.

Usefulness of Direct Peroral Cholangioscopy Using a Multibending Ultraslim Endoscope for the Management of Intrahepatic Bile Duct Lesions (with Videos).

Background/Aims: : Peroral cholangioscopy (POC) has been used to assess intrahepatic duct (IHD) lesions but with a limited role. A new multibending (MB) ultraslim endoscope has been designed to improve POC performance. We evaluated the usefulness of POC using the MB ultraslim endoscope for the management of IHD lesions. Methods: : Between March 2017 and March 2020, 22 patients underwent direct POC using the MB ultraslim endoscope for IHD lesions documented by previous imaging or cholangiopancreatography. The primary outcome was technical success of POC, and secondary outcomes were technical success of POC-guided interventions, median procedure time, and POC-related adverse events. Results: : The technical success rate for POC using the MB ultraslim endoscope for IHD lesions was 95.5% (21/22). Free-hand insertion was successful in 95.2% (20/21). The overall technical success rate for POC-guided intervention was 100% (21/21), including nine diagnostic and 12 therapeutic procedures (eight direct stone removal and four intraductal lithotripsies). The median procedure time was 29 minutes (range, 9 to 79 minutes). There were no procedure-related adverse events. Conclusions: : Direct POC using the MB ultraslim endoscope allows direct visualization of IHD lesions and may be useful for diagnosis and therapeutic management in selected patients.

Beyond Endoscopes: Pilot Study of Surgical Instrument Lumen Inspection.

Objective: Borescope examinations of endoscope channels are commonly described in literature, but no studies on surgical instrument lumen inspection have been published recently. Inadequately processed surgical instruments have been implicated in patient infections. This study assessed the utility of borescopes for inspecting surgical instruments. Methods: The study team inspected and photographed sterilized, patient-ready arthroscopic shaver handpieces and suction tips using a tablet camera and borescopes to characterize internal anatomy, defects found in lumens, and the impact of recleaning on debris or residues. Results: Ten suctions and eight shavers were inspected. All suctions had internal ridges and suction holes that were perpendicular to the lumen. All shavers had visible ridges, elbows, and lever mechanisms inside lumens. Of the 18 instruments, 16 (88%) had internal features that appeared rough or jagged and 17 (94%) had visible debris or discoloration in the lumens. Recleaning efforts generally were effective for suctions, but multiple rounds of recleaning with enhanced steps were less effective for shavers, which were replaced. Researchers documented retained soil and brush bristles in several new shavers despite following manufacturer instructions for cleaning and found visible damage and discoloration within five uses. Discussion: This study demonstrated the value of borescope examinations for surgical instrument lumens. Visual inspections identified anatomical features that could influence cleaning effectiveness and detected residual soil, discoloration, and debris in most instruments. The findings suggested that manufacturer cleaning instructions were insufficient and additional cleaning was not always effective. In response, the site's multidisciplinary team strengthened risk assessment protocols and enhanced their cleaning practices.

Safety and efficacy of one-hole split endoscope technique for surgical treatment of thoracic ossification of the ligamentum flavum.

Surgical intervention is typically recommended for thoracic ossification of the ligamentum flavum (TOLF). This study aimed to evaluate the efficacy and safety of a novel non-coaxial one-hole split endoscope (OSE) technique for treating TOLF. We performed OSE procedure on 13 patients with TOLF from June 2022 to July 2023. The mean operative time was 117.5 ± 15.4 min. VAS scores for lower limbs decreased from 6.5 ± 0.8 preoperative to 1.6 ± 0.4 at the last follow-up (P < 0.001). ODI scores improved from 62.4 ± 5.7 preoperative to 18.6 ± 2.2 at the last follow-up (P < 0.001), and mJOA scores increased from 5.1 ± 1.6 preoperative to 8.4 ± 1.5 at the latest follow-up (P < 0.001). All patients achieved ASIA scale grade D or E at the final follow-up, except for two patients remained residual limb numbness. None of the thirteen patients suffered from severe perioperative complications. The OSE technique proves to be a safe and effective procedure for treating TOLF or even with dura mater ossification, characterized by minimal surgical trauma, relatively smooth learning curve and flexible operation.