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Nasal and Facial Fractures
Published in John C Watkinson, Raymond W Clarke, Louise Jayne Clark, Adam J Donne, R James A England, Hisham M Mehanna, Gerald William McGarry, Sean Carrie, Basic Sciences Endocrine Surgery Rhinology, 2018
Class 2 fractures are the result of greater force and are often associated with significant cosmetic deformity. In addition to fracturing the nasal bones, the frontal process of the maxilla and septum are also involved. However, the ethmoid labyrinth and adjacent orbital structures remain intact (see Class 3). The pattern of deformity is determined by the direction of the force applied. A frontal impact tends to comminute the nasal bones and cause gross flattening and widening of the dorsum; while a lateral impact produces a high deviation of the nasal skeleton.
Anatomy of the Skull Base and Infratemporal Fossa
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
The ethmoid bone consists of: the central perpendicular platethe cribriform platethe paired labyrinths. The midline perpendicular plate forms the central superior aspect of the nasal septum, articulating anteroinferiorly with the quadrilateral cartilage and posteroinferiorly with the vomer. It extends superiorly as the crista galli; either side of the crista lie the cribriform plates, through which pass 20 or so olfactory nerve filaments on each side. The labyrinths, containing numerous air cells, lie medial to the orbit and form part of the lateral wall of the nose, being anterior to the body of the sphenoid. They occupy much of the upper part of the maxillary hiatus, a large defect in the medial aspect of the maxilla, itself closed by several bones, and the medial aspect of these is surgically important in endoscopic sinus surgery. The superior and middle conchae (‘turbinates’) are part of the ethmoidal labyrinth, as is the bulla ethmoidalis anteriorly. The lamina papyracea, the paper-thin orbital plate of the ethmoid, separates the ethmoid sinuses from the orbital cavity, knowledge of which is important for endoscopic access to the medial aspect of the orbit, such as for (medial) periorbital abscess drainage, orbital decompression or access to infraorbital/intrazonal tumours.
Sinus headache and nasal disease
Published in Stephen D. Silberstein, Richard B. Upton, Peter J. Goadsby, Headache in Clinical Practice, 2018
Stephen D. Silberstein, Richard B. Upton, Peter J. Goadsby
The ethmoid bone, a T-shaped structure that supports the bilateral ethmoid labyrinth, forms the lateral nasal wall. The horizontal limb of the T is formed by the cribriform plate, from which the ethmoid labyrinth is suspended. This is a complex structure with multiple bony septa and the medial projections of the superior and middle turbinates. Lateral to the uncinate process, which is a secondary projection of the ethmoid bone, is the infundibuium, a recess into which the maxillary sinus drains. The infundibuium drains into the hiatus semilunaris, which in turn drains into the middle meatus, which is located between the uncinate process and the middle turbinate. The frontal sinus drains into the frontal recess, which may drain into either the middle meatus or the ethmoidal infundibuium. This region is known as the osteomeatal complex11 (maxillary sinus ostium, infundibuium, hiatus semilunaris, middle turbinate, ethmoidal bulla, and frontal ostium). The sphenoidal sinus and posterior ethmoidal cells drain into the sphenoethmoidal recess (Figure 14.2).
The Neurotropic Varicella Zoster Virus: a Case of Isolated Abducens Nerve Palsy without Skin Rash in a Young Healthy Woman
Published in Strabismus, 2021
Maria Elisa Vares Luís, Carlos Diogo Hipólito-Fernandes, José Lopes Moniz, Joana Tavares Ferreira
To analyze the possibility of a demyelinating disease or other CNS process a head Magnetic Resonance Imaging (MRI) with gadolinium was performed. Except for an antral mucosal thickening with partial opacification of ethmoidal labyrinth no other abnormalities such as demyelinating plaques, space-occupying lesion was observed. It was not possible to identify the inflammation of the abducens nerve palsy pair along its path, with the T2 Short-Tau Inversion-Recovery (T2-STIR) MR imaging sequences used.
Impact of the ethmoid volume on endoscopic medial wall decompression outcomes in Graves’ orbitopathy
Published in Acta Oto-Laryngologica, 2020
Pedro Clarós, Agnieszka Waląg, Marta López-Fortuny, Andrés Clarós
About 209 clinical charts (319 orbits) of 252 consecutive patients operated by a single surgeon were analyzed. Six patients were lost to follow-up, and 37 were excluded due to incomplete records, mainly unavailable CT imagining. Postoperative data refer to a minimum 6 months follow-up period. For each patient information recorded included date of surgery, date of birth, age at the time of surgery, sex, eyes operated, smoking status, ethmoid size and the type of thyroid dysfunction (subclinical hypothyroidism, euthyroidism, subclinical hyperthyroidism). Preoperative and postoperative ophthalmological measurements were analyzed and the indication for subsequent strabismus correction and eyelid surgery was established. Exophthalmos was defined as proptosis greater than 18 mm from the lateral orbital rim to the corneal apex on Hertel exophthalmometer or a difference between both eyes greater than 2 mm. Preoperative computed tomography (three planes, bone window, no contrast) was a standard at our institution. The ethmoid length and width were measured in the axial plane and the height was measured in the sagittal plane (Figure 2(A,B)). The ethmoid length (the maximal anteroposterior diameter) was defined as the longest distance from the most anterior point of anterior ethmoid cells to the most posterior point of the anterior wall of the sphenoid sinus on the axial image. The ethmoid width (the maximal transverse diameter) was defined as the longest distance perpendicular from the medial wall of ethmoidal labyrinth to lamina papyracea on the axial image. The ethmoid height (the maximal craniocaudal diameter) was defined as the longest distance from the lowest point of the ethmoid to the highest point of the skull base on the sagittal image. The volume was calculated using the formula reported by Adibelli et al. [18] and later used by Eren et al. [19] which was based on the ethmoid shape resemblance with the ellipsoid. They simplified the ellipsoid volume calculation as volume = 1/2 × A × B × C (A, B, and C were the diameters) and referred to the result as sinus volume index (SVI) which will we use in this article as well. The Ager nasi, Onodi, and Haller cells, the pneumatized uncinate processes, concha bullosa were included in the ethmoid measurements following Stamberger et al. [17].