title: The peri-esophageal connective tissue layers and related compartments: visualization by histology and magnetic resonance imaging.
abstract: An organized layer of connective tissue coursing from aorta to esophagus was recently discovered in the mediastinum. The relations with other peri-esophageal fascias have not been described and it is unclear whether this layer can be visualized by non-invasive imaging. This study aimed to provide a comprehensive description of the peri-esophageal fascias and determine whether the connective tissue layer between aorta and esophagus can be visualized by magnetic resonance imaging (MRI). First, T2-weighted MRI scanning of the thoracic region of a human cadaver was performed, followed by histological examination of transverse sections of the peri-esophageal tissue between the thyroid gland and the diaphragm. Secondly, pretreatment motion-triggered MRI scans were prospectively obtained from 34 patients with esophageal cancer and independently assessed by two radiologists for the presence and location of the connective tissue layer coursing from aorta to esophagus. A layer of connective tissue coursing from the anterior aspect of the descending aorta to the left lateral aspect of the esophagus, with a thin extension coursing to the right pleural reflection, was visualized ex vivo in the cadaver on MR images, macroscopic tissue sections, and after histologic staining, as well as on in vivo MR images. The layer connecting esophagus and aorta was named 'aorto-esophageal ligament' and the layer connecting aorta to the right pleural reflection 'aorto-pleural ligament'. These connective tissue layers divides the posterior mediastinum in an anterior compartment containing the esophagus, (carinal) lymph nodes and vagus nerve, and a posterior compartment, containing the azygos vein, thoracic duct and occasionally lymph nodes. The anterior compartment was named 'peri-esophageal compartment' and the posterior compartment 'para-aortic compartment'. The connective tissue layers superior to the aortic arch and at the diaphragm corresponded with the currently available anatomic descriptions. This study confirms the existence of the previously described connective tissue layer coursing from aorta to esophagus, challenging the long-standing paradigm that no such structure exists. A comprehensive, detailed description of the peri-esophageal fascias is provided and, furthermore, it is shown that the connective tissue layer coursing from aorta to esophagus can be visualized in vivo by MRI.
authors.affiliation: Department of Anatomy, University Medical Center Utrecht, Utrecht, The Netherlands.|Department of Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: T J
authors.initials: TJ
authors.lastname: Weijs
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.|Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: L
authors.initials: L
authors.lastname: Goense
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.|Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: P S N
authors.initials: PSN
authors.lastname: van Rossum
authors.affiliation: Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: G J
authors.initials: GJ
authors.lastname: Meijer
authors.affiliation: Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: A L H M W
authors.initials: AL
authors.lastname: van Lier
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: F J
authors.initials: FJ
authors.lastname: Wessels
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: M N G
authors.initials: MN
authors.lastname: Braat
authors.affiliation: Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: I M
authors.initials: IM
authors.lastname: Lips
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: J P
authors.initials: JP
authors.lastname: Ruurda
authors.affiliation: Department of Surgery, Vrije Universiteit Medical Centre, Amsterdam, the Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Cuesta
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: van Hillegersberg
authors.affiliation: Department of Anatomy, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: R L A W
authors.initials: RL
authors.lastname: Bleys
mesh_terms: D000368:Aged; D002102:Cadaver; D003238:Connective Tissue / Q000000981:diagnostic imaging* / Q000473:pathology*; D004947:Esophagus / Q000000981:diagnostic imaging* / Q000473:pathology*; D006652:Histological Techniques / Q000379:methods* / Q000592:standards; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards; D008297:Male
keywords: esophageal anatomy; esophageal surgery; magnetic resonance imaging; peri-esophageal fascia