Search results for "Foramen"
showing 10 items of 93 documents
Cranial circulation of the pen-tailed tree shrewPtilocercus lowii and relationships of Scandentia
1994
The major cranial arteries and veins are described for a 30-mm crown-rump length fetus of the pen-tailed tree shrewPtilocercus lowii, and comparisons are made with cranial vessels reported in the tree shrewTupaia and with the vascular pattern reconstructed for primitive eutherians.Ptilocercus shares a number of derived features of the cranial circulation withTupaia, which, therefore, represent synapomorphies of tree shrews (Tupaiidae, Scandentia). Included are (1) the enclosure of the intratympanic portion of the internal carotid artery in a bony canal that is floored proximally and distally by the entotympanic and by the petrosal in between, (2) the enclosure of the intratympanic portion o…
Comparison of the shaping characteristics of Neolix and Protaper Universal systems in preparation of severely-curved simulated canals
2017
Background The aim of this in vitro study was to compare the shaping characteristics of two types of nickel-titanium endodontic file systems with regard to the following parameters: Canal straightening, Canal deviation and Instrumentation time. Material and Methods Fifty severely curved canals simulated in resin blocks were prepared to an apical size 25 using Protaper Universal orNeolix systems (n=25 canals/group). The angle of canal curvature was determined before and after instrumentation. Pre- and post-operative images were superimposed to determine any canal deviation. The instrumentation time was also recorded. The data were statistically analyzed by using independent sample t-test and…
Necrosis of the long process of the incus following stapes surgery: new anatomical observations.
2009
Objectives/Hypothesis: The most frequent complication (generally recognized during revision procedures) following seemingly successful stapedotomies and stapedectomies is necrosis of the long process of the incus. This is currently ascribed to a malcrimped stapes prosthesis or to a compromised blood supply of the incus. The two-point fixation can cause a mucosal injury with a resulting toxic reaction, and also osteoclastic activity. An important aspect in the engineering of ideal stapes prostheses is that they should be fixed circularly to the long process of the incus with appropriate strength. The objective of this study was to compare current knowledge relating to the blood supply of the…
DOUBLE TRANSVERSE FORAMEN IN INFANTILE CERVICAL VERTEBRAE OF THE LATE 17TH AND EARLY 18TH CENTURIES. Doble foramen transverso en las vértebras infant…
2016
La presencia de doble foramen transverso es una variante anatómica que se observa con frecuencia en el raquis cervical inferior y que presenta implicaciones clínicas en relación con la arteria vertebral. Aunque en la actualidad existe cierta controversia acerca de si el origen de esta variante cervical es congénito o adquirido, y a pesar de que la presencia de doble foramen transverso en población infantil descartaría un origen degenerativo-artrósico, se encuentra una falta de información acerca de su presencia en vértebras cervicales infantiles. En este sentido, nuestro objetivo ha sido analizar la presencia de doble foramen transverso en vértebras cervicales infantiles procedentes de rest…
Agujero Transverso Bipartito en población rural del siglo XVII y en poblablación actual
2015
INTRODUCCIÓN La columna cervical se diferencia claramente de la región torácica y lumbar, tanto en su anatomía como en su biomecánica (Kapandji IA, 2007). Asimismo, la región cervical debe conciliar su gran movilidad con su papel clave en el paso de estructuras vasculares y nerviosas relacionadas con la región craneal (Gray H, 1989; Das, S et al, 2005; Drake RL et al, 2010; White TD et al, 2011). En este sentido, entre los rasgos anatómicos distintivos de las vértebras cervicales, se encuentra un orificio en las apófisis transversas, denominado foramen transverso, a través del cual asciende la arteria vertebral (White TD et al, 2011; Moore KL et al, 2013). Con respecto a los diámetros anter…
Iatrogenic pulmonary artery dissection in patient with ostium secundum interatrial septum defect
2020
Pulmonary artery dissection is a rare and lethal condition. Few cases are reported in the literature, and most are derived from autopsies. In most cases, pulmonary artery dissection is a complication of chronic pulmonary hypertension leading to pulmonary artery aneurysm but there are other causes. We describe a case of iatrogenic pulmonary artery dissection in an elderly patient with ostium secundum defect. In particular, we describe the role of cardiac magnetic resonance in making this diagnosis and guiding future therapeutic decisions.
Minimally Invasive Surgery for Decompression in Chiari I Malformation
2019
Chiari malformations (CMs) includes different pathologies sharing common anatomic deformities of the brainstem and cerebellum. CM type I was originally introduced by Hans Chiari and described as an “elongation of the tonsils and the medial parts of the inferior lobes of the cerebellum into cone-shaped projections which accompany the medulla oblongata into the spinal canal.” The prevalence of CM has been estimated to be between 0.1% and 0.5%, but it is possible that higher rates will be identified since the increasing the use of magnetic resonance imaging (MRI) in common clinical practice. Clinical studies have shown an equal prevalence in both sexes without particular ethnic or geographic d…
Endoscopic Neurosurgery “Around the Corner” with a Rigid Endoscope. Technical Note
1999
Endoscopically "working around the corner" is presently restricted to the use of flexible endoscopes or an endoscope-assisted microneurosurgical (EAM) technique. In order to overcome the limitations of these solutions, endoscopic equipment and techniques were developed for "working around the corner" with rigid endoscopes. A steering insert with a 5 French working channel is capable of steering instruments around the corner by actively bending the guiding track and consecutively the instrument. A special fixation device enables strict axial rotation of the endoscope in the operating field. Endoscopic procedures "around the corner", including aqueductal stenting, pellucidotomy, third ventric…
Orofacial clinical features in Arnold Chiari type I malformation: A case series
2017
Background Arnold Chiari malformation (ACM) is characterized by an anatomical defect at the base of the skull where the cerebellum and the spinal cord herniate through the foramen magnum into the cervical spinal canal. Among the subtypes of the condition, ACM type I (ACM-I) is particularly outstanding because of the severity of symptoms. This study aimed to analyze the orofacial clinical manifestations of patients with ACM-I, and discuss their demographic distribution and clinical features in light of the literature. Material and methods A case series with patients with ACM-I treated between 2012 and 2015 was described. The sample consisted of patients who were referred by the Department of…