Heads-up Surgery: Endoscopes and Exoscopes for Otology and Neurotology in the Era of the COVID-19 Pandemic.

A new era of surgical visualization and magnification is poised to disrupt the field of otology and neurotology. The once revolutionary benefits of the binocular microscope now are shared with rigid endoscopes and exoscopes. These 2 modalities are complementary. The endoscope improves visualization of the hidden recesses through the external auditory canal or canal-up mastoidectomy. The exoscope provides an immersive visual experience and superior ergonomics compared with binocular microscopy. Endoscopes and exoscopes are poised to disrupt the standard of care for surgical visualization and magnification in otology and neurotology.

In Vivo Evaluation of a Miniaturized Fluorescence Molecular Tomography (FMT) Endoscope for Breast Cancer Detection Using Targeted Nanoprobes.

In this study, in vivo animal experiments with 12 nude mice bearing breast-cancer-patient-tissue-derived xenograft (PDX) tumors were performed aiming to verify the imaging capability of a novel miniaturized fluorescence molecular tomography (FMT) endoscope, in combination with targeted nanoparticle-near-infrared (NIR) dye conjugates. Tumor-bearing mice were divided into two groups by systematic injection with urokinase plasminogen activator receptor-targeted (n = 7) and nontargeted (n = 5) imaging nanoprobes as a contrast agent, respectively. Each mouse was imaged at 6, 24, and 48 h following the injection of nanoprobes using the FMT endoscope. The results show that systemic delivery of targeted nanoprobes produced a 4-fold enhancement in fluorescence signals from tumors, compared with tumors that received nontargeted nanoprobes. This study indicates that our miniaturized FMT endoscope, coupled with the targeted nanoparticle-NIR dye conjugates as a contrast agent, has high sensitivity and specificity, and thus great potential to be used for image-guided detection and removal of a primary tumor and local metastatic tumors during surgery.

Quality Systems Approach for Endoscope Reprocessing: You Don't Know What You Don't Know!

Several factors affect the efficacy of endoscope reprocessing, including human factors, inadequate cleaning, simethicone residuals, moisture in channels during storage, and biofilm or buildup biofilm formation. These factors all contribute to contamination of patient-ready endoscopes that may contribute to transmission of microorganisms resulting in infection and/or colonization. This article reviews monitoring as part of a quality management system that includes manual cleaning, dry storage, and culture to detect endoscope contamination. The published data for rapid tests that detect organic residuals and adenosine triphosphate to monitor manual cleaning are reviewed.

Endoscopic mask innovation and protective measures changes during the coronavirus disease-2019 pandemic: Experience from a Chinese hepato-biliary-pancreatic unit.

Endoscopy is widely used as a clinical diagnosis and treatment method for certain hepatobiliary and pancreatic diseases. However, due to the distinctive epidemiological characteristics of severe acute respiratory syndrome coronavirus 2, the virus causing coronavirus disease-2019 (COVID-19), healthcare providers are exposed to the patient's respiratory and gastrointestinal fluids, rendering endoscopy a high risk for transmitting a nosocomial infection. This article introduces preventive measures for endoscopic treatment enacted in our medical center during COVID-19, including the adjustment of indications, the application of endoscope protective equipment, the design and application of endoscopic masks and splash-proof films, and novel recommendations for bedside endoscope pre-sterilization.

[Chinese Expert Consensus Statement on Clinical Evaluation System of Medical Endoscopy].

Nowadays, there is a rising development and popularity of medical endoscopes. The international brand dominates the endoscope market. The market size of domestic brands is also growing rapidly. The electronic technologies of hard or soft endoscopes are developing rapidly and gradually approaching to the advanced level in worldwide. However, at present, there is a lack of relevant standards for national standards and industry regulations for evaluating medical endoscopes, and also lacking of quantitative and clear understanding of the gap between domestic and foreign products. It is urgently necessary to give a comprehensive and accurate evaluation to the medical endoscopes. In this context, the expert group has established a scientific, systematic, and applicable standardized medical endoscopy clinical evaluation system to standardize various endoscopic evaluation indicators.

Reprocessing of flexible endoscopes and endoscopic accessories used in gastrointestinal endoscopy: Position Statement of the European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastroenterology Nurses and Associates (ESGENA) - Update 2018.

This Position Statement from the European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology Nurses and Associates (ESGENA) sets standards for the reprocessing of flexible endoscopes and endoscopic devices used in gastroenterology. An expert working group of gastroenterologists, endoscopy nurses, chemists, microbiologists, and industry representatives provides updated recommendations on all aspects of reprocessing in order to maintain hygiene and infection control.

Stapedotomy using a 4 mm endoscope: any advantage over a microscope?

OBJECTIVES: To ascertain the feasibility of endoscopic (4 mm) stapedotomy, and compare intra- and post-operative variations with microscopic stapedotomies. METHODS: Forty otosclerosis patients were scheduled for microscopic or endoscopic stapedotomy. Intra-operative variables compared were: incision, canalplasty, canal wall curettage for ossicular assessment, chorda tympani manipulation, ability to perform stapes footplate perforation before its supra-structure removal, and operative time. Post-operative variables compared were ear pain and hearing improvement. RESULTS: Of the 20 microscopy patients, 4 required endaural incision and canalplasty because of canal overhangs, and 7 required canal wall curettage for ossicular assessment. None of the 20 endoscopy patients required these procedures. Chorda tympani was manipulated in 13 and 6 patients in the microscopy and endoscopy groups respectively, while the stapes footplate could be perforated in 5 and 11 patients respectively. Mean operative time was 50.25 and 76.05 minutes in the microscopy and endoscopy groups respectively. In the endoscopy group, mean air-bone gap was 37.12 and 10.73 dB pre- and post-operation respectively; in the microscopy group, these values were 35.95 and 13.81 dB. CONCLUSION: Endoscopic stapedotomy has comparable hearing outcomes. Sinonasal endoscope serves as a better tool for: minimal incision, canalplasty avoidance, less chorda tympani mobilisation, and stapes footplate perforation ability.

Fast calibration of electromagnetically tracked oblique-viewing rigid endoscopes.

PURPOSE: The oblique-viewing (i.e., angled) rigid endoscope is a commonly used tool in conventional endoscopic surgeries. The relative rotation between its two moveable parts, the telescope and the camera head, creates a rotation offset between the actual and the projection of an object in the camera image. A calibration method tailored to compensate such offset is needed. METHODS: We developed a fast calibration method for oblique-viewing rigid endoscopes suitable for clinical use. In contrast to prior approaches based on optical tracking, we used electromagnetic (EM) tracking as the external tracking hardware to improve compactness and practicality. Two EM sensors were mounted on the telescope and the camera head, respectively, with considerations to minimize EM tracking errors. Single-image calibration was incorporated into the method, and a sterilizable plate, laser-marked with the calibration pattern, was also developed. Furthermore, we proposed a general algorithm to estimate the rotation center in the camera image. Formulas for updating the camera matrix in terms of clockwise and counterclockwise rotations were also developed. RESULTS: The proposed calibration method was validated using a conventional [Formula: see text], 5-mm laparoscope. Freehand calibrations were performed using the proposed method, and the calibration time averaged 2 min and 8 s. The calibration accuracy was evaluated in a simulated clinical setting with several surgical tools present in the magnetic field of EM tracking. The root-mean-square re-projection error averaged 4.9 pixel (range 2.4-8.5 pixel, with image resolution of [Formula: see text] for rotation angles ranged from [Formula: see text] to [Formula: see text]. CONCLUSIONS: We developed a method for fast and accurate calibration of oblique-viewing rigid endoscopes. The method was also designed to be performed in the operating room and will therefore support clinical translation of many emerging endoscopic computer-assisted surgical systems.

Performance of a fully disposable, digital, single-operator cholangiopancreatoscope.

Background and study aim Our aim was to evaluate the first use in humans of a new, single-use, digital, single-operator intraductal cholangiopancreatoscopy system (IDCP). Patients and methods Data were collected retrospectively from four US institutions between February 2015 and April 2015. The visual impression of neoplasia or benign findings with IDCP was determined by the performing endoscopist. High grade dysplasia, intraductal papillary mucinous neoplasm, neuroendocrine tumor, and malignancy were categorized as neoplasia. Benign disease was defined as the absence of neoplasia during ≥ 6 months of follow-up. Results Patients (n = 108) with indeterminate strictures, dilatation, or difficult stones underwent IDCP. Of 74 patients with indeterminate stricture or dilatation, 29 (39 %) had neoplasia, of which 25 were confirmed by miniature biopsy forceps, 2 by surgical pathology, and 2 by the presence of metastatic disease on follow-up imaging. In patients with benign disease, 15 had concentric stenosis or normal/erythematous changes, 5 had low papillary mucosal projections, 6 had coarse granular mucosa, and 4 had nodular mucosa. Findings in patients with neoplastic disease included dilated, tortuous vessels ("tumor vessels"; n = 13), irregular margins with partial occlusion of the lumen (infiltrative stricture, n = 12), villous or nodular mass (n = 9), and finger-like villiform projections (n = 5). Operating characteristics for indeterminate stricture or dilatation were: 97 % sensitivity, 93 % specificity, 90 % positive predictive value, 98 % negative predictive value. Targeted biopsy yielded 86 % sensitivity and 100 % specificity. Stone clearance was noted in all cases. Adverse events occurred in 3 %. Conclusion The new IDCP system provides enhanced image resolution, and may improve the ability to target difficult stones and diagnose indeterminate strictures.

Review of Techniques to Achieve Optical Surface Cleanliness and Their Potential Application to Surgical Endoscopes.

A clear visualization of the operative field is of critical importance in endoscopic surgery. During surgery the endoscope lens can get fouled by body fluids (eg, blood), ground substance, rinsing fluid, bone dust, or smoke plumes, resulting in visual impairment. As a result, surgeons spend part of the procedure on intermittent cleaning of the endoscope lens. Current cleaning methods that rely on manual wiping or a lens irrigation system are still far from ideal, leading to longer procedure times, dirtying of the surgical site, and reduced visual acuity, potentially reducing patient safety. With the goal of finding a solution to these issues, a literature review was conducted to identify and categorize existing techniques capable of achieving optically clean surfaces, and to show which techniques can potentially be implemented in surgical practice. The review found that the most promising method for achieving surface cleanliness consists of a hybrid solution, namely, that of a hydrophilic or hydrophobic coating on the endoscope lens and the use of the existing lens irrigation system.

[Some Thoughts on Risk Prevention of Endoscopic Instruments].

There is a certain risk of nosocomial infection within the use of endoscopic instruments including trocars for laparoscope use. Attention should be paid to the content of the product manual in the seventh chapter of the industry standard YY 0672.1-2008. This paper proposes some comments and suggestions on this issue. We suggest there should add some contents in product manual.

Transparent antifouling material for improved operative field visibility in endoscopy.

Camera-guided instruments, such as endoscopes, have become an essential component of contemporary medicine. The 15-20 million endoscopies performed every year in the United States alone demonstrate the tremendous impact of this technology. However, doctors heavily rely on the visual feedback provided by the endoscope camera, which is routinely compromised when body fluids and fogging occlude the lens, requiring lengthy cleaning procedures that include irrigation, tissue rubbing, suction, and even temporary removal of the endoscope for external cleaning. Bronchoscopies are especially affected because they are performed on delicate tissue, in high-humidity environments with exposure to extremely adhesive biological fluids such as mucus and blood. Here, we present a repellent, liquid-infused coating on an endoscope lens capable of preventing vision loss after repeated submersions in blood and mucus. The material properties of the coating, including conformability, mechanical adhesion, transparency, oil type, and biocompatibility, were optimized in comprehensive in vitro and ex vivo studies. Extensive bronchoscopy procedures performed in vivo on porcine lungs showed significantly reduced fouling, resulting in either unnecessary or ∼10-15 times shorter and less intensive lens clearing procedures compared with an untreated endoscope. We believe that the material developed in this study opens up opportunities in the design of next-generation endoscopes that will improve visual field, display unprecedented antibacterial and antifouling properties, reduce the duration of the procedure, and enable visualization of currently unreachable parts of the body, thus offering enormous potential for disease diagnosis and treatment.

Design and validation of a near-infrared fluorescence endoscope for detection of early esophageal malignancy.

Barrett's esophagus is a known precursor lesion to esophageal adenocarcinoma. In these patients, early detection of premalignant disease, known as dysplasia, allows curative minimally invasive endoscopic therapy, but is confounded by a lack of contrast in white light endoscopy. Imaging fluorescently labeled lectins applied topically to the tissue has the potential to more accurately delineate dysplasia, but tissue autofluorescence limits both sensitivity and contrast when operating in the visible region. To overcome this challenge, we synthesized near-infrared (NIR) fluorescent wheat germ agglutinin (WGA-IR800CW) and constructed a clinically translatable bimodal NIR and white light endoscope. Images of NIR and white light with a field of view of 63 deg and an image resolution of 182 µm are coregistered and the honeycomb artifact arising from the fiber bundle is removed. A minimum detectable concentration of 110 nM was determined using a dilution series of WGA-IR800CW. We demonstrated ex vivo that this system can distinguish between gastric and squamous tissue types in mouse stomachs (p=0.0005) and accurately detect WGA-IR800CW fluorescence in human esophageal resections (compared with a gold standard imaging system, rs>0.90). Based on these findings, future work will optimize the bimodal endoscopic system for clinical trials in Barrett's surveillance.

The vacuum cleaner effect in minimally invasive percutaneous nephrolitholapaxy.

INTRODUCTION: Percutaneous stone removal increasingly plays an important role among the different approaches of interventional stone therapy, particularly since the development of miniaturized instruments is resulting in lower morbidity for the patients. One major drawback of smaller instruments is the increased difficulty of stone retrieval after disintegration due to the reduced tract diameter. This results in longer operation time and the need of additional tools such as disposable retrieval baskets. One of the key factors in the development of minimally invasive percutaneous nephrolitholapaxy (MIP) was the design of an Amplatz sheath which provides a built-in vacuum cleaner effect for stone retrieval. METHODS: A series of flow analyses with the gauges and shapes of the most commonly used nephroscopes and sheaths in percutaneous nephrolitholapaxy was performed by computational fluid dynamics. Flow velocity and direction in front of the nephroscope were computed and visualized by the software. RESULTS: In our study, the vacuum cleaner effect developed exclusively when a round-shaped nephroscope was used (Nagele Miniature Nephroscope System, Karl Storz GmbH & Co. KG) and depended on the relation between nephroscope diameter and inner sheath diameter. The strongest effect was observed with a 12 F nephroscope and an inner sheath diameter of 15 F. It did not develop when an oval- or crescent-shaped nephroscope was used. In front of the distal end of the round-shaped nephroscope, a slipstream develops, induced by the excursive change of width of the fluid flow on the outlet of the flushing canal. This allows the adhesion of a stone fragment in the eddy while the fluid flow is circulating around the stone. CONCLUSION: This study illustrates and explains the vacuum cleaner effect which has been detected in the development of the Nagele Miniature Nephroscope System used in MIP. It combines the reduced morbidity of smaller kidney puncture diameters with the benefit of quick and complete stone removal.

New techniques on the horizon: interventional radiology and interventional endoscopy of the urinary tract ('endourology').

PRACTICAL RELEVANCE: Interventional radiology and interventional endoscopy (IR/IE) uses contemporary imaging modalities, such as fluoroscopy and endoscopy, to perform diagnostic and therapeutic procedures in various body parts. The majority of IR/IE procedures currently undertaken in veterinary medicine pertain to the urinary tract, and this subspecialty has been termed 'endourology'. This technology treats diseases of the renal pelvis, ureter(s), bladder and urethra. In human medicine, endourology has overtaken traditional open urologic surgery in the past 20-30 years, and in veterinary medicine similar progress is occurring. AIM: This article presents a brief overview of some of the more common IR/IE procedures currently being performed for the treatment of urinary tract disease in veterinary patients. These techniques include percutaneous nephrolithotomy for lithotripsy of problematic nephrolithiasis, mesenchymal stem cell therapy for chronic kidney disease, sclerotherapy for the treatment of idiopathic renal hematuria, various diversion techniques for ureteral obstructions, laser lithotripsy for lower urinary tract stone disease, percutaneous cystolithotomy for removal of bladder stones, hydraulic occluder placement for refractory urinary incontinence, percutaneous cystostomy tube placement for bladder diversion, urethral stenting for benign and malignant urethral obstructions, and antegrade urethral catheterization for treatment of urethral tears. EVIDENCE BASE: The majority of the data presented in this article is solely the experience of the author, and some of this has only been published and/or presented in abstract form or small case series. For information on traditional surgical approaches to these ailments readers are encouraged to evaluate other sources.

Hand-eye and radial distortion calibration for rigid endoscopes.

BACKGROUND: In this paper, we propose a non-linear calibration method for hand-eye system equipped with a camera undergoing radial distortion as the rigid endoscope. Whereas classic methods propose either a separated estimation of the camera intrinsics and the hand-eye transform or a mixed non-linear estimation of both hand-eye and camera intrinsics assuming a pin-hole model, the proposed approach enables a simultaneous refinement of the hand-eye and the camera parameters including the distortion factor with only three frames of the calibrated pattern. METHODS: Our approach relies on three steps: (i) linear initial estimates of hand-eye and radial distortion with minimum number of frames: one single image to estimate the radial distortion and three frames to estimate the initial hand-eye transform, (ii) we propose to express the camera extrinsic with respect to hand-eye and world-grid transforms and (iii) we run bundle adjustment on the reprojection error with respect to the distortion parameters, the camera intrinsics and the hand-eye transform. RESULTS: Our method is quantitatively compared with state-of-the-art linear and non-linear methods. We show that our method provides a 3D reconstruction error of approximately 5% of the size of the 3D shape. CONCLUSIONS: Our experimental results show the effectiveness of simultaneously estimating hand-eye and distortion parameters for 3D reconstruction.

Factors determining the quality of screening colonoscopy: a prospective study on adenoma detection rates, from 12,134 examinations (Berlin colonoscopy project 3, BECOP-3).

BACKGROUND: Screening colonoscopy (SC) outcome quality is best determined by the adenoma detection rate (ADR). The substantial variability in the ADRs between endoscopists may reflect different skills, experience and/or equipment. OBJECTIVE: To analyse the potential factors that may influence ADR variance, including case volume. DESIGN: 12,134 consecutive SCs (mean age 64.5 years, 47% men) from 21 Berlin private-practice colonoscopists were prospectively studied during 18 months. The data were analysed using a two-level mixed linear model to adequately address the characteristics of patients and colonoscopists. The ADR was regressed after considering the following factors: sex, age, bowel cleanliness, NSAID intake, annual SC case volume, lifetime experience, instrument withdrawal times, instrument generations used, and the number of annual continuing medical education (CME) meetings attended by the physician. The case volume was also retrospectively analysed from the 2007 national SC registry data (312,903 colonoscopies and 1004 colonoscopists). RESULTS: The patient factors that correlated with the ADR were sex, age (p<0.001) and low quality of bowel preparation (p=0.005). The factors that were related to the colonoscopists were the number of CME meetings attended (p=0.012) and instrument generation (p=0.001); these factors accounted for approximately 40% of the interphysician variability. Within a narrow range (6-11 min), the withdrawal time was not correlated with the ADR. Annual screening case volume did not correlate with the ADR, and this finding was confirmed by the German registry data. CONCLUSIONS: The outcome quality of screening colonoscopies is mainly influenced by individual colonoscopist factors (ie, CME activities) and instrument quality. CLINICAL TRIAL REGISTRATION NUMBER: Clinical Trial Gov Registration number: NCT00860665.

Guidelines for reprocessing nonlumened heat-sensitive ear/nose/throat endoscopes.

Endoscopes have become an indispensable instrument in the daily activity of the ear/nose/throat (ENT) department, but their use has introduced potential health risks such as the transmission of infection. Over the years, scientific knowledge has been consolidated regarding the most appropriate ways for the correct disinfection, and numerous guidelines have been issued for both digestive and respiratory endoscopes, whereas to date specific references to ENT endoscopes do not exist. The diagnostic ENT endoscope does not generally have an operative channel; it is shorter and thinner and has a much more frequent usage, also in the outpatient setting. As a consequence, the guidelines for digestive or respiratory endoscopes are not always functional for the ENT department in that they do not take into account the dynamics or the intensity of the work performed therein. This article proposes: 1) to standardize the correct way to carry out the disinfection procedure of heat-sensitive nonlumened ENT endoscopes to reduce to a minimum the possibility of errors or oversights; and 2) to guarantee the disinfection within a limited time frame, appropriate for an ENT outpatient department. In the initial phase, the critical areas encountered in ENT endoscopy are determined. This is followed by an examination of the literature to identify existing guidelines for the reprocessing of endoscopes (mainly digestive and respiratory), with a view to establishing a common disinfection procedure for nonlumened ENT endoscopes. Finally, the new methods of disinfection developed specifically for the reprocessing of ENT endoscopes are examined and discussed.

Validation of sleep nasendoscopy for assessment of snoring with bispectral index monitoring.

Bispectral index (BIS) monitor is a neurophysiological monitoring device which continually analyses a patient's electroencephalogram during sedation and general anaesthesia to assess the level of consciousness and depth of anaesthesia. BIS monitoring, whilst performing sleep nasendoscopy (using midazolam and propofol), has helped validate depth of sedation and allowed comparison with levels of sedation of control patients during natural sleep. A prospective study of 30 patients with snoring undergoing sleep nasendoscopy with BIS monitoring was conducted. BIS monitoring was recorded throughout the procedure and assessment of snoring was made at the appropriate level of sedation and snoring. BIS values were compared with control patients. The 30 patients undergoing sleep nasendoscopy had average BIS values ranging from 50.72 to 61.2. Similar results were seen with BIS and oxygen saturation in the control group. BIS monitoring provides an adjunct to the assessment of sleep nasendoscopy in determining the level of sedation required for snoring assessment. Comparable BIS values and oxygen saturation levels were obtained between controls and patients during sedation-induced sleep, thus validating the role of sleep nasendoscopy.