Endoscopic Landmarks Research Articles

S902 Evaluating the Visual Accuracy of Gemini Pro 1.5 and GPT-4o in Identifying Endoscopic Anatomical Landmarks

S902 Evaluating the Visual Accuracy of Gemini Pro 1.5 and GPT-4o in Identifying Endoscopic Anatomical Landmarks

Endoscopic landmarks corresponding to anatomical landmarks for esophageal subsite classification.

Individual treatment strategies for esophageal cancer have been investigated based on the anatomical subsite classification. Accurate subsite classification based on these anatomical landmarks is thus important. We investigated the suitability of the existing endoscopic classification and explored alternative landmarks for esophageal subsite classification. Patients who received endoscopic ultrasonography (and computed tomography scans for surveillance of esophageal cancer treatment or esophageal submucosal tumors were included. Distances between anatomical landmarks, including the inferior cricoid cartilage border, superior border of the sternum, and tracheal bifurcation, were measured using a combination of endoscopic ultrasonography, computed tomography, and other information. The mean (standard deviation) distances from the superior incisor dentition to the pharynx-esophagus, cervical-upper thoracic esophagus, and upper-middle thoracic esophagus boundaries were 16.9 (1.7), 21.7 (1.9), and 29.0 (1.9) cm, respectively. However, variances in the differences between the mean and individual distances were large (2.8, 3.4, and 3.7, respectively), mainly because of differences in body height. However, variances in the differences between individual distances and novel endoscopic landmarks, including the lower end of the pyriform sinus and lower end of compression of the left main bronchus, were lower (1.7, 1.2, and 0.6, respectively). Existing indicators of esophageal subsite boundaries were not consistent with anatomical boundaries. Modification of the distance from the superior incisor dentition based on average distances from anatomical landmarks or the use of alternative endoscopic landmarks is recommended to provide more suitable anatomical boundaries.

Endonasal Endoscopic Anatomy of the Orbito-Cavernous-Pterygopalatine Interface: Multilayer Anatomical Description and Landmarks to Define the Limits of the Compartments

Despite growing interest in the endoscopic endonasal approach (EEA) to the medial orbital apex (OA), a comprehensive description of the multilayer topology lying at the intersection of the regional compartments is missing. An EEA to the OA, pterygopalatine fossa, and cavernous sinus was performed in 20 specimens. A 360° layer-by-layer dissection was performed taking into consideration relevant anatomical aspects of the interface and documented with 3-dimensional technologies. Endoscopic landmarks were analyzed to provide an outline of the compartments and identify critical structures. Additionally, the consistency of a previously described reference called orbital apex convergence prominence was analyzed and a method to identify its position was introduced. The orbital apex convergence prominence was an inconsistent finding (15%). However, a craniometric method introduced in this study proved to be reliable to reach the orbital apex convergence point. Additional structures such as the sphenoethmoidal suture and a 3-suture junction (sphenoethmoidal-palatoethmoidal-palatosphenoidal) helped to identify the posterior limit of the OA and define a keyhole to access the compartments of the interface. We defined the bone limits of the "optic risk zone," an area where the optic nerve is more susceptible to damage. Furthermore, an orbital fusion line (periorbita-dura-periosteum) was identified and divided into 4 segments according to adjacent structures: optic, cavernous, pterygopalatine, and infraorbital. Understanding cranial landmarks and the folds of the layers covering the orbito-cavernous-pterygopalatine interface can facilitate tailoring an EEA to the medial orbital space and avoid unnecessary exposure of sensitive anatomy in the vicinity.

Adherence to Quality Indicators for Diagnosis and Surveillance of Barrett's Esophagus: A Comparative Study of Barrett's Experts and Nonexperts

Background and AimsThere is considerable variability in adherence to endoscopic quality indicators (QIs) for Barrett's esophagus (BE). The aims of this study were to (1) assess adherence to published Qis for diagnosis and surveillance of BE, (2) compare adherence between BE experts and nonexperts, and (3) identify factors associated with adherence. MethodsWe identified all patients with BE on esophagogastroduodenoscopy between 2010 and 2018. QIs evaluated included inspection using high-definition white light endoscopy, use of the Prague Classification, identification of endoscopic landmarks, use of the Seattle Protocol, and guideline-adherent recommendations for surveillance or endoscopic eradication therapy. BE experts and nonexperts were compared using logistic mixed-effects models. ResultsA total of 467 patients were identified, with BE experts performing fewer overall esophagogastroduodenoscopies (n = 162, 34.7% vs n = 305, 65.3%). Whereas BE experts were more likely to document Prague Classification (52.5% vs 41.3%; P = 0.017) and landmarks (43.2% vs 22.6%; P = 0.036), there was no significant difference between experts and nonexperts in use of high-definition white light endoscopy (8.6% vs 3.3%; P = 0.123), Seattle Protocol (48.1% vs 40.3%; P = 0.313), or guideline-adherent surveillance or treatment recommendations (71.0% vs 67.5%; P = 0.509). Patient enrollment in a BE surveillance program was the only factor associated with improved QI adherence, specifically adherence to Prague Classification documentation (OR 1.85, 95% CI 1.08-3.14; P = 0.025), Seattle Protocol (1.28, 95% CI 1.16-1.50; P < 0.001), and follow-up recommendations (OR 2.64, 95% CI 1.55-4.48; P < 0.001). ConclusionPatterns of adherence to published QIs for endoscopy in patients with BE are mostly independent of expertise. Further training initiatives are needed to standardize the performance of endoscopic practice in patients with BE.

Endoscopic “retrograde” dacryocystorhinostomy: A fast route to the lacrimal sac

Endoscopic Dacryocystorhinostomy (DCR) is an established surgical technique for the management of peripheral nasolacrimal duct (NLD) obstruction. Its main points are the correct identification of the lacrimal sac and the execution of surgical procedures that allow a rapid and accurate healing of the surgical field. The main endoscopic landmarks used for the identification of the lacrimal sac are the middle turbinate and the maxillary line.However, in some cases, this procedure can be difficult due to several factors (e.g. anatomical variations, former surgery).In the present study, a variation of “classic” endoscopic DCR, named “retrograde” endoscopic endonasal DCR (rDCR), is described. rDCR is performed through the quick identification of the NLD at the level of the most anterior insertion of the inferior turbinate in the lateral nasal wall. In most cases, at this level only a very thin shell of bone is present (crack point), easily fractured by using blunt angled dissector. The duct is then followed upward along its course by removing the overlying bone in order to correctly identify the lacrimal sac and unequivocally drill along the lacrimal pathway. This technique proved to be a safe, quick and effective procedure, even in patients with difficult anatomy.

BIOPASS hybrid navigation for endoscopic sinus surgery - an assistance system

Previous navigation systems can determine the position of the "tracked" surgical instrument in CT images in the context of functional endoscopic sinus surgery (FESS), but do not provide any assistance directly in the video endoscopic image of the surgeon. Developing this direct assistance for intraoperative orientation and risk reduction was the goal of the BIOPASS project (Bild Ontologie und prozessgestütztes Assistenzsystem). The Project pursues the development of a novel navigation system for FESS without markers. BIOPASS describes a hybrid system that integrates various sensor data and makes it available. The goal is to abandon tracking and exclusively provide navigation information directly in the video image. This paper describes the first step of the development by collecting and structuring the surgical phases (workflows), the video endoscopic landmarks and a first clinical evaluation of the model version. The results provide the important basis and platform for the next step of the project.

Topographic Anatomy of the Medial Labyrinthine Wall: Implications for the Transcanal Endoscopic Approach to the Internal Auditory Canal.

To characterize transcanal endoscopic landmarks of the medial labyrinthine wall and correlate these with anatomical features of the fundus of the internal auditory canal (IAC). The transcanal transpromontorial approach (TTA) enables minimally invasive access to the IAC. The establishment of a landmark-based dissection technique for the approach is crucial to avoid injury to the facial nerve. Twenty temporal bones were dissected endoscopically through the TTA. Furthermore, high-resolution computed tomography (CT) scans from ten adult normal temporal bones were analyzed and three-dimensionally reconstructed. A stepwise dissection technique for the TTA was demonstrated depending on a newly described landmark used in the identification of the facial nerve. The proposed landmark, which was named the intervestibulocochlear crest (IVCC), is an integrated part of the otic capsule. It can be differentiated after the excision of the lateral labyrinthine wall as a laterally based bony pyramid between the cochlea and the vestibule. Its medially directed apex blends with the central part of the falcifrom crest and points to the distal part of the meatal facial nerve. The IVCC is best detected on axial CT images at the level of the tympanic facial nerve. The union between the IVCC and the falciform crest appears radiologically as a short stem or mini-martini glass. The proposed IVCC is a novel landmark with a consistent relationship to the IAC fundus and the facial nerve. It may be utilized in conjunction with the falciform crest to identify the facial nerve during minimally invasive transcanal surgeries.

Rio de Janeiro Global Consensus on Landmarks, Definitions, and Classifications in Barrett’s Esophagus: World Endoscopy Organization Delphi Study

Despite the significant advances made in the diagnosis and treatment of Barrett's esophagus (BE), there is still a need for standardized definitions, appropriate recognition of endoscopic landmarks, and consistent use of classification systems. Current controversies in basic definitions of BE and the relative lack of anatomic knowledge are significant barriers to uniform documentation. We aimed to provide consensus-driven recommendations for uniform reporting and global application. The World Endoscopy Organization Barrett's Esophagus Committee appointed leaders to develop an evidence-based Delphi study. A working group of 6 members identified and formulated 23 statements, and 30 internationally recognized experts from 18 countries participated in 3 rounds of voting. We defined consensus as agreement by ≥80% of experts for each statement and used the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool to assess the quality of evidence and the strength of recommendations. After 3 rounds of voting, experts achieved consensus on 6 endoscopic landmarks (palisade vessels, gastroesophageal junction, squamocolumnar junction, lesion location, extraluminal compressions, and quadrant orientation), 13 definitions (BE, hiatus hernia, squamous islands, columnar islands, Barrett's endoscopic therapy, endoscopic resection, endoscopic ablation, systematic inspection, complete eradication of intestinal metaplasia, complete eradication of dysplasia, residual disease, recurrent disease, and failure of endoscopic therapy), and 4 classification systems (Prague, Los Angeles, Paris, and Barrett's International NBI Group). In round 1, 18 statements (78%) reached consensus, with 12 (67%) receiving strong agreement from more than half of the experts. In round 2, 4 of the remaining statements (80%) reached consensus, with 1 statement receiving strong agreement from 50% of the experts. In the third round, a consensus was reached on the remaining statement. We developed evidence-based, consensus-driven statements on endoscopic landmarks, definitions, and classifications of BE. These recommendations may facilitate global uniform reporting in BE.

Functional endoscopic sinus surgery outcome in chronic rhinosinusitis patients with hypoplastic maxillary sinus.

To review the clinical characteristics, prevalence and outcomes of chronic rhinosinusitis patients with a hypoplastic maxillary sinus who underwent functional endoscopic sinus surgery. A retrospective review was performed for the 814 consecutive, elective functional endoscopic sinus surgery procedures performed at an academic centre from 2010 to 2020, to identify patients with a hypoplastic maxillary sinus. A total of 56 hypoplastic maxillary sinus cases were detected. Maxillary sinus hypoplasia presented unilaterally in 20 cases and bilaterally in 18 cases. Of the maxillary sinus hypoplasia cases, 38 were type I, 17 were type II and 1 was type III. The average Lund-McKay score was 8.6. No major post-operative complications were reported. Four patients had minor complications and one had persistent post-nasal drip. Functional endoscopic sinus surgery is a safe and effective procedure for improving the clinical condition of patients with a hypoplastic maxillary sinus; however, careful pre-operative radiological evaluation, identification of intra-operative endoscopic landmarks and use of additional techniques may be essential to achieve satisfactory results and avoid possible serious complications.

Computed tomography analysis of the anterior ethmoid genu of the frontal recess in non-diseased sinuses.

Knowledge of anatomical variations of the frontal recess and frontal sinus and recognition of endoscopic landmarks are vital for safe and effective endoscopic sinus surgery. This study revisited an anatomical landmark in the frontal recess that could serve as a guide to the frontal sinus. Prevalence of the anterior ethmoid genu, its morphology and its relationship with the frontal sinus drainage pathway was assessed. Computed tomography scans with multiplanar reconstruction were used to study non-diseased sinonasal complexes. The anterior ethmoidal genu was present in all 102 anatomical sides studied, independent of age, gender and race. Its position was within the frontal sinus drainage pathway, and the drainage pathway was medial to it in 98 of 102 cases. The anterior ethmoidal genu sometimes extended laterally and formed a recess bounded by the lamina papyracea laterally, by the uncinate process anteriorly and by the bulla ethmoidalis posteriorly. Distance of the anterior ethmoidal genu to frontal ostia can be determined by the height of the posterior wall of the agger nasi cell rather than its volume or other dimensions. This study confirmed that the anterior ethmoidal genu is a constant anatomical structure positioned within frontal sinus drainage pathway. The description of anterior ethmoidal genu found in this study explained the anatomical connection between the agger nasi cell, uncinate process and bulla ethmoidalis and its structural organisation.

S3276 Review of American and International Guidelines for Endoscopic Management of Barrett's Esophagus

Introduction: Gastroesophageal reflux disease (GERD) is seen in approximately 10 to 20 % of the Western population. Complications of GERD include Barrett’s esophagus (BE) and esophageal adenocarcinoma (EAC). EAC has been increasing in the past few decades and now encompasses over 60% of all esophageal cancers in the US. Dysplasia in BE further increases the risk of progression from low grade dysplasia (LGD) to high grade dysplasia (HGD) and eventually EAC.The objective of this study was to perform a review of the current guidelines from American and international gastroenterology societies for the endoscopic management of BE. Methods: Guidelines and recommendations from major American and other prominent international GI societies were reviewed from January 25th to 29th, 2021 on the management of BE. We included ACG, AGA, ASGE, ESGE, BSG, SFED, Japanese GI and Internal Medicine societies, CAG, and AMG. Results: While there is a common consensus among the international GI community in diagnosis and management of BE, there are also major notable differences. Screening for BE in the general population is usually not recommended but many suggest individualized assessment. The American societies generally manage nondysplastic Barrett’s esophagus (NDBE) with surveillance endoscopy every 3 to 5 years. However, the ASGE considers endoscopic ablation (RFA) in high-risk groups. After diagnosis of BE is made, the majority provide guidelines for surveillance intervals based on the presence and grading of dysplasia. The ESGE, BSG, and SFED provide varying intervals for NDBE based on BE segment length. Endoscopic eradication therapy (EET) is recommended by some societies for LGD, while all societies recommend it for HGD. Post-EET surveillance is often performed in practice, but officially recommended by 5 out of 9 societies. EAC only accounts for 5% of all esophageal cancers in Japan. Additionally, Japanese societies do not require intestinal metaplasia for diagnosis of BE and also have different endoscopic landmarks for the gastroesophageal junction, biopsy protocols, and histologic definition of BE. Conclusion: Most societies agree on endoscopic surveillance for NDBE and EET for HGD. Endoscopic therapy with RFA for NDBE is controversial and not widely accepted. However, EET for LGD is becoming more common in the US and some parts of Europe. BE in Japan is diagnosed and managed differently than in the West; further studies are warranted to provide a fair comparison.

Accuracy and applicability of the artificial intelligence integrated software in Z-line segmentation

Conducted from April 2019 to July 2020, this study aimed to assess the software accuracy in assisting Z-line segmentation by comparing with medical doctors’ detection results and by recording doctors’ satisfaction in scale, time-of-implementation in interactive mode, and integrated mode. For the development of the Z-line detection algorithm, a dataset of 533 high-definition endoscopic WLI (white-light) images in diverse forms of Z-line were collected. The software was subsequently developed in 4 modes, including manual mode, interactive mode (using Superpixels-BPT), automatic mode (using AI algorithm), and integrated mode (the combination of BPT and U-Net). 30 endoscopic images were assigned to 2 groups of doctors (under 2-year experience and over 5-year experience) for the Z-line detection using the software in 4 modes. Time-of-implementation, number of mouse clicks, satisfaction in scales, and IoU (Interception over Union) metric with expert’s ground-truth are used for assessment. The results showed that IoU metrics of interactive and integrated modes in the experimental dataset was 88% with no statistical difference to the IoU value of manual mode, and mean IoU metrics from the results of 4 modes were high, from 86.7 to 90.8%. The mean values of time-of-implementation in interactive mode and integrated mode were not statistically different from manual mode. The median number of mouse-clicks each use in the interactive mode and the integrated mode were 24.5 and 15.5 times, respectively. The software received good feedbacks from the doctors, with the mean values of satisfaction scores of automatic mode, interactive mode and integrated mode are 7.2, 7.3, and 7.2 respectively. The development of the software for detecting endoscopic anatomy landmarks is a novel and feasible research direction in Vietnam. Further studies could focus on detecting some specific lesions classified according to anatomy landmarks.

Transoral Endoscopic Localization of the Parapharyngeal Internal Carotid Artery.

Objectives To define transoral endoscopic surgical landmarks for the parapharyngeal segment of the internal carotid artery (ppICA) using cadaveric dissection. Methods Ten fresh cadaveric heads were dissected to demonstrate the parapharyngeal space anatomy and course of the ppICA as seen in a transoral approach. Anatomical measurements of the distance between the ppICA and bony landmarks were recorded and analyzed. Results The stylohyoid ligament, styloglossus, and stylopharyngeus could be considered to be the safe anterior boundary of the ppICA in the transoral approach; among them, the styloid ligament was the most rigid tissue. Dissection between the stylopharyngeus muscle and superior pharyngeal constrictor muscle provides direct access to the ppICA. At the level of the skull base, the distance from the root of the styloid process to the lateral margin of the external aperture of the carotid canal on the left side and on the right side was 8.57 ± 1.97 and 8.80 ± 1.21 mm, respectively. At the level of the maxillary tuberosity, the distance from the ppICA to the maxillary tuberosity on the left side and on the right side was 31.48 ± 2.24 and 31.01 ± 2.88 mm, respectively. Conclusion The endoscopic-assisted transoral approach can facilitate exposure of the ppICA. The root of the styloid process, styloid ligament, and maxillary tuberosity are critical landmarks in the identification of the ppICA in the transoral approach.

Surgical nuances of the expanded endoscopic anterior skull base craniectomy for hyperostotic meningioma resection.

The rostral expanded endoscopic approach (EEA) to anterior cranial fossa (ACF) has several advantages over transcranial/craniofacial surgery, providing early access to the vascular supply of tumors and reducing morbidities of craniotomy especially that of brain retraction. This article presents endoscopic landmarks and nuances for a wide ACF corridor, with stepwise image-guided dissections highlighting surgical tricks and techniques to enhance surgical safety. We describe an expanded endoscopic endonasal anterior skull base craniectomy for a recurrent large olfactory groove hyperostotic meningioma, with correlated cadaveric dissections. The widening of rostral EEA can provide a safe and feasible route to access ACF. This article highlights the specific landmarks in endoscopic anatomy with reference to the angle of visualization and bayonetted instruments.

The endoscopic anatomy of the cochlear hook region and fustis: surgical implications.

SUMMARYThe cochlear hook region can be considered as the interface between the middle and inner ear. The identification of surgically-relevant endoscopic landmarks of this anatomical entity and assessment of their clinical value is still lacking in the literature. Procedures like cholesteatoma surgery and minimal invasive endoscopic approaches to the lateral skull base may particularly benefit from these considerations. We hypothesize that the spatial orientation of anatomical landmarks in the cochlear hook can be expressed in angles and are reproducibly identifiable by transcanal otoendoscopy. Therefore, endoscopic dissection of the cochlear hook region was performed in 32 temporal bone specimens. Topographic anatomy was documented and analysed. We performed computed tomography of 28 specimens to assess the region in three-dimensional reconstructions. The mean angle between the round window and the basal scala tympani was assessed 25.9° in endoscopic and 28.2° in three-dimensionally reconstructed models. The fustis was recognised as a reliable landmark for the basal turn. A mean angle of 155.4° to the basal scala tympani was assessed. A slight bulging without obstruction of the basal turn was observed in 5 cases. The utility of the revealed anatomical details was assessed in minimal invasive endoscopic lateral skull base approaches. In conclusion, we described the angles between anatomical landmarks of the cochlear hook region. Moreover, the angle as recorded through an endoscope was found to be reliable compared to three-dimensional reconstructions from computed tomography.

Advanced CT imaging demonstrating the bulla lamella and the basal lamella of the middle turbinate as endoscopic landmarks for the anterior ethmoid artery

Advanced CT imaging demonstrating the bulla lamella and the basal lamella of the middle turbinate as endoscopic landmarks for the anterior ethmoid artery

Ilececum: A Comprehensive Review.

For gastrointestinal endoscopists, the ileocecum is the finishing line during colonoscopy and it is identified by three endoscopic landmarks: terminal ileum, ileocecal valve, and the appendiceal orifice. Although ileal intubation is recommended during routine screening colonoscopy, it is not required in most cases of screening colonoscopy. Ileal intubation is indicated in certain circumstances such as suspected inflammatory bowel disease and GI bleeding. There is much pathology that can be observed within the ileocecum. Careful and systematic examination should be stressed during GI endoscopic training and practice. In this review, the authors demonstrate its anatomy, endoscopic findings, and pathologies.

Morphometric Analysis of the Orbital Process of the Palatine Bone and its Relationship to Endoscopic Orbital Apex Surgery.

Endoscopic approaches to the orbit improve the ability to directly access apical lesions while minimizing manipulation of normal structures. Inferomedial orbital access is limited by the orbital process of the palatine bone (OPPB) which prevents dissection and retraction in the inferolateral vector. The objective of this study was to examine the morphometric characteristics of the OPPB and quantify the benefit of complete resection to surgical access. Morphometric osteologic measurements of the OPPB were performed in 59 human skulls. A radius subtended by the OPPB was calculated to generate a hemispheric dissection corridor achievable by complete resection of the OPPB. Cadaveric and live surgical dissections were then performed on 15 orbits to develop discreet endoscopic surgical landmarks which could be used to both identify the OPPB and verify complete resection. The mean(± SD) radius of the OPPB was 0.47 ± 0.28 cm. Complete OPPB resection provided an additional 0.36 ± 0.42 cm of surgical exposure within the inferomedial apex. Relative to the Caucasian (n = 27) skulls, the radii in the Asian (n = 27) and African (n = 5) skulls were significantly smaller (p < 0.001 and p = 0.02, respectively). The OPPB significantly limits surgical access to the inferomedial orbital apex during endoscopic approaches. Complete surgical resection of the OPPB improves surgical exposure facilitating retraction of the inferior rectus muscle and circumferential dissection of lesions within this space. Knowledge of the morphology and clinical relevance of this structure provides an opportunity to improve surgical exposure for relevant pathologic assessment and optimize endoscopic surgical outcomes.

Radioanatomic Study of the Greater Palatine Canal Relevant to Endoscopic Endonasal Surgical Landmarks.

Objective A radioanatomic study of surgically relevant variations in the greater palatine canal (GPC) on computed tomography (CT) was performed to determine susceptibility during endoscopic endonasal procedures. Study Design Blinded radioanatomic analysis. Setting Tertiary university hospital. Subjects and Methods Fifty consecutive paranasal CT scans (100 sides) were analyzed. Measurements were standardized to landmarks such as the inferior turbinate (IT) and floor of the nasal cavity (FNC) to assess variability and vulnerability of the nerve. Measurements included (1) incidence of maxillary sinus pneumatization posterior to the GPC, (2) distance from the posterior wall of the maxillary sinus to the GPC at the IT and FNC, (3) width of bone containing the GPC, (4) incidence of medial GPC dehiscence, and (5) angle of the GPC extending from the IT to FNC. Results Ninety-one percent of maxillary sinuses were pneumatized posterior to the GPC. The distance from the posterior wall of the maxillary sinus to the GPC was 2.8 ± 1.7 mm (range, -2.3 to 5.9) at the posterior attachment of the IT and 4.1 ± 3.1 mm (range, -6.3 to 11.9) at the FNC. The width of bone containing the GPC was 3.3 ± 1.3 mm (range, 1-8.9), and the medial bony GPC was dehiscent in 38% of cases. In the sagittal plane, the angle of the GPC between the IT and the FNC was 31.9 ± 6.9 degrees (range, 10.8-45). Conclusion The GPC has considerable anatomic variability relative to important surgical landmarks in endoscopic procedures. Preoperative review of CTs to assess vulnerability may prevent postoperative complications.

Virtual Mapping of the Frontal Recess: Guiding Safe and Efficient Frontal Sinus Surgery.

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