3D Reconstruction of the Morpho-Functional Topography of the Human Vagal Trigone

Abstract

The Vagal Trigone, often referred to as Ala Cinerea, is a triangular-shaped area of the floor of the fourth ventricle that is strictly involved in the network of chardiochronotropic, baroceptive, respiratory, and gastrointestinal control systems of the medulla oblongata. While it is frequently identified as the superficial landmark for the underlying Dorsal Motor Nucleus of the Vagus, this correspondence is not univocal in anatomical literature and is often oversimplified in neuroanatomy textbooks and neurosurgical atlases. As the structure represents an important landmark for neurosurgical procedures involving the floor of the fourth ventricle, accurate morphological characterization is required to avoid unwanted side effects (e.g., bradychardia, hypertension) during neuorphysiological monitoring and cranial nerve nuclei stimulation in intraoperative settings. The aim of this study was to address the anatomo-topographical relationships of the Vagal Trigone with the underlying nuclei. For this purpose, we have conducted an anatomo-microscopical examination of serial sections deriving from 54 Human Brainstems followed by 3D reconstruction and rendering of the specimens. Our findings indicate that the Vagal Trigone corresponds only partially with the Dorsal Motor Nucleus of the Vagus, while most of its axial profile is occupied by the dorsal regions of the Solitary Tract Nucleus. Furthermore, basing on literature and our findings we speculate that the neuroblasts of the Dorsal Motor Nucleus of the Vagus undergo neurobiotaxic migration induced by the neuroblasts of the dorsolaterally located solitary tract nucleus, giving rise to the Ala Cinerea, a topographically defined area for parasympathetic visceral control.

Infrapatellar Fat Pad-Synovial Membrane Anatomo-Fuctional Unit: Microscopic Basis for Piezo1/2 Mechanosensors Involvement in Osteoarthritis Pain

“…Photomicrographs were acquired under a Leica DM4500B microscope (Leica Microsystems) connected to a Leica DFC320 high-resolution digital camera (Leica Microsystems). Image processing was performed through softwares for image acquisition (QWin, Leica Microsystems) and analysis (ImageJ), as previously reported ( Porzionato et al, 2020 ; Emmi et al, 2021 ) ( Figure 1 ).…”

“…Image processing was performed through softwares for image acquisition (QWin, Leica Microsystems) and analysis (ImageJ), as previously reported (Porzionato et al, 2020;Emmi et al, 2021) (Figure 1).…”

COVID-19 Neuropathology: Evidence for SARS-CoV-2 invasion of Human Brainstem Nuclei

“…However, when comparing COVID-19 patients with and without viral immunoreactivity, no statistically signi cant differences in the overall degree of brainstem microgliosis were found, as seen in Figure 5. Hence, microglial activation does not appear to be directly related to neuronal invasion of SARS-CoV-2 within affected regions, but could represent the consequence of systemic infection / cytokine storm ongoing during COVID-19 affecting topographic compartments of the brainstem with an intrinsic anatomical vulnerability, such as the medullary tegmentum, and the substantia nigra [34][35] . Furthermore, COVID-19 is characterized by different evolutionary phases and heterogeneous individual responses, and the short interval between infection and death in our cohort (mean hospitalization time = 14 days) and the fact that included patients died during the acute phase of the disease, may not be su cient to determine detectable neuropathological alterations as a direct consequence of viral invasion, which may require more time to develop 3,31 .…”

Topography and distribution of adenosine A2A and dopamine D2 receptors in the human Subthalamic Nucleus

“…Ten (10) Human Brains with no history of neurological or psychiatric disorders obtained from the Body Donation Program of the Institute of Human Anatomy of University of Padova ( Porzionato et al, 2012 ; Emmi et al, 2021a , b ) were employed for the study. All procedures were carried out according to the ethical standards of the Body Donation Program and to the Declaration of Helsinki.…”