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Ginzel M, Huber N, Bauer L, Kluth D, Metzger R. Development of the foregut and the formation of the trachea and esophagus in rat embryos. A symphony of confusion. Front Cell Dev Biol 2023; 11:1092753. [PMID: 36824366 PMCID: PMC9941168 DOI: 10.3389/fcell.2023.1092753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 01/23/2023] [Indexed: 02/10/2023] Open
Abstract
Introduction: During embryonic development, the trachea emerges from an area of the foregut, which is often referred to as "anterior" or "common" foregut tube or simply foregut. To explain this process of differentiation, four competing models exist to date. The outgrowth and watershed models propose a foregut that remains constant in length. In the outgrowth model, the trachea buds off and elongates from the foregut, while in the watershed model, a mesenchymal wedge splits the growing foregut into the trachea and esophagus. In contrast, the septation model proposes a cranial splitting and thus a shortening of the "common" foregut tube into the trachea and esophagus by an emerging septum. Finally, the splitting and extension model describes an interaction of cranial splitting of the foregut and simultaneous caudal tracheal and esophageal growth. Methods: Here we examine the development of the undifferentiated foregut by micro computed tomography, which allows precise measurements. Results: Our results show that this area of the foregut transforms into the larynx, a process, which is independent from tracheal and esophageal development. Discussion: These observations are only consistent with the outgrowth model.
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Affiliation(s)
- Marco Ginzel
- Department of Pediatric and Adolescent Surgery, Paracelsus Medical University Hospital, Salzburg, Austria,*Correspondence: Marco Ginzel,
| | - Nana Huber
- Department of Pediatric and Adolescent Surgery, Paracelsus Medical University Hospital, Salzburg, Austria
| | - Leopold Bauer
- Department of Pediatric and Adolescent Surgery, Paracelsus Medical University Hospital, Salzburg, Austria
| | - Dietrich Kluth
- Department of Pediatric Surgery, University Hospital Leipzig, Leipzig, Germany
| | - Roman Metzger
- Department of Pediatric and Adolescent Surgery, Paracelsus Medical University Hospital, Salzburg, Austria
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2
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Anatomy and embryology of tracheo-esophageal fistula. Semin Pediatr Surg 2022; 31:151231. [PMID: 36459913 DOI: 10.1016/j.sempedsurg.2022.151231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Anomalies in tracheo-esophageal development result in a spectrum of congenital malformations ranging from, most commonly, esophageal atresia with or without trachea-esophageal fistula (EA+/-TEF) to esophageal web, duplication, stricture, tracheomalacia and tracheal agenesis. Despite the relative frequency of EA, however, the underlying etiology remains unknown and is likely due to a combination of genetic, epigenetic and environmental factors. In recent years, animal models have dramatically increased our understanding of the molecular and morphological processes involved in normal esophageal development during the key stages of anterior-posterior regionalization, dorsal-ventral patterning and morphogenic separation. Moreover, the use of animal models in conjunction with increasingly advanced techniques such as genomic sequencing, sophisticated live imaging studies and organoid models have more recently cast light on potential mechanisms involved in EA pathogenesis. This article aims to unravel some of the mysteries behind the anatomy and embryology of EA whilst providing insights into future directions for research.
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Mostafa H, Hussein MT, Abd‐Elnaeim M. Developmental events in the lung of the Japanese quail (
Coturnix coturnix japonica
): Morphological, histochemical and electron‐microscopic studies. Microsc Res Tech 2022; 85:3761-3776. [DOI: 10.1002/jemt.24225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 06/13/2022] [Accepted: 08/09/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Heba Mostafa
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine Assiut University Assiut Egypt
| | - Manal T. Hussein
- Department of Cell and Tissues, Faculty of Veterinary Medicine Assiut University Assiut Egypt
| | - Mahmoud Abd‐Elnaeim
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine Assiut University Assiut Egypt
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4
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Bugter O, Li Y, Wolters AH, Agrawal V, Dravid A, Chang A, Hardillo J, Giepmans BN, Baatenburg de Jong RJ, Amelink A, Backman V, Robinson DJ. Early Upper Aerodigestive Tract Cancer Detection Using Electron Microscopy to Reveal Chromatin Packing Alterations in Buccal Mucosa Cells. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2021; 27:878-888. [PMID: 34108070 PMCID: PMC8939050 DOI: 10.1017/s1431927621000507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A profound characteristic of field cancerization is alterations in chromatin packing. This study aimed to quantify these alterations using electron microscopy image analysis of buccal mucosa cells of laryngeal, esophageal, and lung cancer patients. Analysis was done on normal-appearing mucosa, believed to be within the cancerization field, and not tumor itself. Large-scale electron microscopy (nanotomy) images were acquired of cancer patients and controls. Within the nuclei, the chromatin packing of euchromatin and heterochromatin was characterized. Furthermore, the chromatin organization was quantified through chromatin packing density scaling. A significant difference was found between the cancer and control groups in the chromatin packing density scaling parameter for length scales below the optical diffraction limit (200 nm) in both the euchromatin (p = 0.002) and the heterochromatin (p = 0.006). The chromatin packing scaling analysis also indicated that the chromatin organization of cancer patients deviated significantly from the control group. They might allow for novel strategies for cancer risk stratification and diagnosis with high sensitivity. This could aid clinicians in personalizing screening strategies for high-risk patients and follow-up strategies for treated cancer patients.
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Affiliation(s)
- Oisín Bugter
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
- Center for Optical Diagnostics and Therapy, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
| | - Yue Li
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Anouk H.G. Wolters
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, the Netherlands
| | - Vasundhara Agrawal
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Amil Dravid
- Department of Electrical Engineering and Computer Science, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Andrew Chang
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Jose Hardillo
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
| | - Ben N.G. Giepmans
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, the Netherlands
| | - Robert J. Baatenburg de Jong
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
| | - Arjen Amelink
- Department of Optics, the Netherlands Organization for Applied Scientific Research (TNO), Stieltjesweg 1, 2628 CK Delft, the Netherlands
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, the Netherlands
| | - Vadim Backman
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Dominic J. Robinson
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
- Center for Optical Diagnostics and Therapy, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
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5
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Bugter O, Hardillo JA, Baatenburg de Jong RJ, Amelink A, Robinson DJ. Optical pre-screening for laryngeal cancer using reflectance spectroscopy of the buccal mucosa. BIOMEDICAL OPTICS EXPRESS 2018; 9:4665-4678. [PMID: 30319894 PMCID: PMC6179391 DOI: 10.1364/boe.9.004665] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/06/2018] [Accepted: 08/06/2018] [Indexed: 05/04/2023]
Abstract
A new approach in early cancer detection focuses on detecting field cancerization (FC) instead of the tumor itself. The aim of the current study is to investigate whether reflectance spectroscopy can detect FC in the buccal mucosa of patients with laryngeal cancer. The optical properties of the buccal mucosa of patients were measured with multidiameter single-fiber reflectance spectroscopy. The blood oxygen saturation and blood volume fraction were significantly lower in the buccal mucosa of laryngeal cancer patients than in non-oncologic controls. The data of these two parameters were combined to form a single 'biomarker α', which optimally discriminates these two groups. Alpha was lower in the laryngeal cancer group (0.28) than the control group (0.30, p = 0.007). Alpha could identify oncologic patients with a sensitivity of 78% and a specificity of 74%. These results might be the first step toward optical pre-screening for laryngeal cancer.
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Affiliation(s)
- Oisín Bugter
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, 's-Gravendijkwal 230, 3015 CE Rotterdam, the Netherlands
- Center for Optical Diagnostics and Therapy, Erasmus MC Cancer Institute, 's-Gravendijkwal 230, 3015 CE Rotterdam, the Netherlands
| | - Jose A. Hardillo
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, 's-Gravendijkwal 230, 3015 CE Rotterdam, the Netherlands
| | - Robert J. Baatenburg de Jong
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, 's-Gravendijkwal 230, 3015 CE Rotterdam, the Netherlands
| | - Arjen Amelink
- Department of Optics, the Netherlands Organization for Applied Scientific Research (TNO), Stieltjesweg 1, 2628 CK Delft, the Netherlands
| | - Dominic J. Robinson
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, 's-Gravendijkwal 230, 3015 CE Rotterdam, the Netherlands
- Center for Optical Diagnostics and Therapy, Erasmus MC Cancer Institute, 's-Gravendijkwal 230, 3015 CE Rotterdam, the Netherlands
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6
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Wosen JE, Mukhopadhyay D, Macaubas C, Mellins ED. Epithelial MHC Class II Expression and Its Role in Antigen Presentation in the Gastrointestinal and Respiratory Tracts. Front Immunol 2018; 9:2144. [PMID: 30319613 PMCID: PMC6167424 DOI: 10.3389/fimmu.2018.02144] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 08/30/2018] [Indexed: 12/13/2022] Open
Abstract
As the primary barrier between an organism and its environment, epithelial cells are well-positioned to regulate tolerance while preserving immunity against pathogens. Class II major histocompatibility complex molecules (MHC class II) are highly expressed on the surface of epithelial cells (ECs) in both the lung and intestine, although the functional consequences of this expression are not fully understood. Here, we summarize current information regarding the interactions that regulate the expression of EC MHC class II in health and disease. We then evaluate the potential role of EC as non-professional antigen presenting cells. Finally, we explore future areas of study and the potential contribution of epithelial surfaces to gut-lung crosstalk.
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Affiliation(s)
- Jonathan E Wosen
- Program in Immunology, Department of Pediatrics, Stanford University, Stanford, CA, United States
| | - Dhriti Mukhopadhyay
- Program in Immunology, Department of Pediatrics, Stanford University, Stanford, CA, United States
| | - Claudia Macaubas
- Program in Immunology, Department of Pediatrics, Stanford University, Stanford, CA, United States
| | - Elizabeth D Mellins
- Program in Immunology, Department of Pediatrics, Stanford University, Stanford, CA, United States
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Abstract
Esophageal duplication and congenital esophageal stenosis (CES) may represent diseases with common embryologic etiologies, namely, faulty tracheoesophageal separation and differentiation. Here, we will re-enforce definitions for these diseases as well as review their embryology, diagnosis, and treatment.
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Affiliation(s)
- A Francois Trappey
- David Grant Medical Center, Travis Air Force Base, California; Division of Trauma, Acute Care Surgery, and Surgical Critical Care, UC Davis Medical Center, Sacramento, California
| | - Shinjiro Hirose
- Department of Surgery, UC Davis Medical Center, Sacramento, California; Division of Pediatric General, Thoracic, and Fetal Surgery, UC Davis Medical Center, Sacramento, California; Shriners Hospitals for Children-Northern California, 2425 Stockton Blvd, Sacramento, California 95817.
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8
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9
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Zhang Y, Jiang M, Kim E, Lin S, Liu K, Lan X, Que J. Development and stem cells of the esophagus. Semin Cell Dev Biol 2016; 66:25-35. [PMID: 28007661 DOI: 10.1016/j.semcdb.2016.12.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 12/16/2016] [Accepted: 12/16/2016] [Indexed: 02/07/2023]
Abstract
The esophagus is derived from the anterior portion of the developmental intermediate foregut, a structure that also gives rise to other organs including the trachea, lung, and stomach. Genetic studies have shown that multiple signaling pathways (e.g. Bmp) and transcription factors (e.g. SOX2) are required for the separation of the esophagus from the neighboring respiratory system. Notably, some of these signaling pathways and transcription factors continue to play essential roles in the subsequent morphogenesis of the esophageal epithelium which undergoes a simple columnar-to-stratified squamous conversion. Reactivation of the relevant signaling pathways has also been associated with pathogenesis of esophageal diseases that affect the epithelium and its stem cells in adults. In this review we will summarize these findings. We will also discuss new data regarding the cell-of-origin for the striated and smooth muscles surrounding the esophagus and how they are differentiated from the mesenchyme during development.
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Affiliation(s)
- Yongchun Zhang
- Division of Digestive and Liver Diseases and Center for Human Development, Department of Medicine, Columbia University, NY 10032, USA
| | - Ming Jiang
- Division of Digestive and Liver Diseases and Center for Human Development, Department of Medicine, Columbia University, NY 10032, USA
| | - Eugene Kim
- Division of Digestive and Liver Diseases and Center for Human Development, Department of Medicine, Columbia University, NY 10032, USA
| | - Sijie Lin
- Division of Digestive and Liver Diseases and Center for Human Development, Department of Medicine, Columbia University, NY 10032, USA
| | - Kuancan Liu
- Division of Digestive and Liver Diseases and Center for Human Development, Department of Medicine, Columbia University, NY 10032, USA; Institute for Laboratory Medicine, Fuzhou General Hospital, PLA, Fuzhou, Fujian 350025, PR China
| | - Xiaopeng Lan
- Institute for Laboratory Medicine, Fuzhou General Hospital, PLA, Fuzhou, Fujian 350025, PR China
| | - Jianwen Que
- Division of Digestive and Liver Diseases and Center for Human Development, Department of Medicine, Columbia University, NY 10032, USA.
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10
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Congenital Tracheal Web Malformation in a Wild Brown Bear ( Ursus arctos ), Sweden, 2010. J Wildl Dis 2016; 52:411-3. [PMID: 27054473 DOI: 10.7589/2015-05-118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We describe a congenital tracheal web malformation in a wild female brown bear (Ursus arctos) yearling that was euthanized after being hit by a train in Norrbotten County, Sweden, December 2010. A 3-cm-long, abnormal, longitudinal mucosal fold divided the trachea into two halves, without obviously blocking the airflow.
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11
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Tapia IE. Mini-symposium: Upper Airway Anomalies. Paediatr Respir Rev 2016; 17:1-2. [PMID: 26620224 DOI: 10.1016/j.prrv.2015.09.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 09/17/2015] [Indexed: 12/28/2022]
Affiliation(s)
- Ignacio E Tapia
- Perelman School of Medicine at the University of Pennsylvania, Attending Physician, Division of Pulmonary Medicine, The Children's Hospital of Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA 19104.
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12
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Zinovyeva MV, Kostina MB, Monastyrskaya GS, Sass AV, Filyukova OB, Vinogradova TV, Kopantzev EP, Sverdlov ED. Genetic markers for lung and esophagus common precursor cells in human development. DOKL BIOCHEM BIOPHYS 2015; 463:203-8. [DOI: 10.1134/s1607672915040031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Indexed: 11/23/2022]
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13
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Que J. The initial establishment and epithelial morphogenesis of the esophagus: a new model of tracheal-esophageal separation and transition of simple columnar into stratified squamous epithelium in the developing esophagus. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2015; 4:419-30. [PMID: 25727889 DOI: 10.1002/wdev.179] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 01/06/2015] [Accepted: 01/23/2015] [Indexed: 11/07/2022]
Abstract
The esophagus and trachea are tubular organs that initially share a single common lumen in the anterior foregut. Several models have been proposed to explain how this single-lumen developmental intermediate generates two tubular organs. However, new evidence suggests that these models are not comprehensive. I will first briefly review these models and then propose a novel 'splitting and extension' model based on our in vitro modeling of the foregut separation process. Signaling molecules (e.g., SHHs, WNTs, BMPs) and transcription factors (e.g., NKX2.1 and SOX2) are critical for the separation of the foregut. Intriguingly, some of these molecules continue to play essential roles during the transition of simple columnar into stratified squamous epithelium in the developing esophagus, and they are also closely involved in epithelial maintenance in the adults. Alterations in the levels of these molecules have been associated with the initiation and progression of several esophageal diseases and cancer in adults.
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Affiliation(s)
- Jianwen Que
- Department of Biomedical Genetics, University of Rochester, Rochester, NY, USA
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Cuesta MA, Weijs TJ, Bleys RLAW, van Hillegersberg R, van Berge Henegouwen MI, Gisbertz SS, Ruurda JP, Straatman J, Osugi H, van der Peet DL. A new concept of the anatomy of the thoracic oesophagus: the meso-oesophagus. Observational study during thoracoscopic esophagectomy. Surg Endosc 2014; 29:2576-82. [PMID: 25480608 DOI: 10.1007/s00464-014-3972-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Accepted: 10/28/2014] [Indexed: 01/14/2023]
Abstract
BACKGROUND During thoracoscopic oesophageal surgery, we observed not previously described fascia-like structures. Description of similar structures in rectal cancer surgery was of paramount importance in improving the quality of resection. Therefore, we aimed to describe a new comprehensive concept of the surgical anatomy of the thoracic oesophagus with definition of the meso-oesophagus. METHODS We retrospectively evaluated 35 consecutive unedited videos of thoracoscopic oesophageal resections for cancer, to determine the surgical anatomy of the oesophageal fascia's vessels and lymphatic drainage. The resulting concept was validated in a prospective study, including 20 patients at three different centres. Additional confirmation was sought by a histologic study of a cadaver's thorax. RESULTS A thin layer of connective tissue around the infracarinal oesophagus, involving the lymph nodes at the level of the carina, was observed during thoracoscopic esophagectomy in 32 of the 35 patients included in the retrospective study and in 19 of the 20 patients included in the prospective study. A thick fascia-like structure from the upper thoracic aperture to the lower thoracic aperture was visualized in all patients. This fascia is encountered between the descending aorta and left aspect of the infracarinal oesophagus. Above the carina it expands on both sides of the oesophagus to lateral mediastinal structures. This fascia contains oesophageal vessels, lymph vessels and nodes and nerves. The histologic study confirmed these findings. CONCLUSIONS Here we described the concept of the "meso-oesophagus". Applying the description of the meso-oesophagus will create a better understanding of the oesophageal anatomy, leading to more adequate and reproducible surgery.
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Affiliation(s)
- Miguel A Cuesta
- Department of Surgery, Vrije Universiteit Medical Centre, de Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands,
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15
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Billmyre KK, Hutson M, Klingensmith J. One shall become two: Separation of the esophagus and trachea from the common foregut tube. Dev Dyn 2014; 244:277-88. [PMID: 25329576 DOI: 10.1002/dvdy.24219] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 10/14/2014] [Accepted: 10/14/2014] [Indexed: 12/23/2022] Open
Abstract
The alimentary and respiratory organ systems arise from a common endodermal origin, the anterior foregut tube. Formation of the esophagus from the dorsal region and the trachea from the ventral region of the foregut primordium occurs by means of a poorly understood compartmentalization process. Disruption of this process can result in severe birth defects, such as esophageal atresia and tracheo-esphageal fistula (EA/TEF), in which the lumina of the trachea and esophagus remain connected. Here we summarize the signaling networks known to be necessary for regulating dorsoventral patterning within the common foregut tube and cellular behaviors that may occur during normal foregut compartmentalization. We propose that dorsoventral patterning serves to establish a lateral region of the foregut tube that is capable of undergoing specialized cellular rearrangements, culminating in compartmentalization. We review established as well as new rodent models that may be useful in addressing this hypothesis. Finally, we discuss new experimental models that could help elucidate the mechanism behind foregut compartmentalization. An integrated approach to future foregut morphogenesis research will allow for a better understanding of this complex process.
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