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Post-Traumatic Orbital Reconstruction: Anatomical Landmarks and the Concept of the Deep Orbit
Published in Niall MH McLeod, Peter A Brennan, 50 Landmark Papers every Oral & Maxillofacial Surgeon Should Know, 2020
As increased exposure is required, the authors identify the need to mobilise the orbital contents via division of the contents of the inferior orbital fissure. This is a crucial principle and allows increased surgical access, as well as aiding hemostasis.
Orbit
Published in Swati Goyal, Neuroradiology, 2020
The inferior orbital fissure, present between the floor and the lateral wall of the orbit, contains the inferior ophthalmic vein, the infraorbital artery, and the infraorbital nerve (a branch of the maxillary division of trigeminal nerve). The infraorbital foramen crosses the floor of the orbit and carries the infraorbital artery, vein, and nerve from the inferior orbital fissure.
Central nervous system
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
The inferior orbital fissure is situated between the greater wing of sphenoid and the maxilla at the junction of the lateral wall and floor. It transmits the maxillary branch of the trigeminal nerve and the infraorbital artery. The optic foramen or canal, which is situated at the apex of the orbit in the sphenoid bone, transmits the optic nerve and the ophthalmic artery. The optic nerves from both eyeballs intercommunicate at the optic chiasma, which is situated in the middle cranial fossa anterior to the sella turcica. The optic tract then passes posteriorly through the lateral geniculate bodies to the visual cortex in the occipital lobe of the cerebrum.
Orbital cavernous venous malformation with partial bone encasement
Published in Orbit, 2023
Quillan M. Austria, Ann Q. Tran, Andrea A. Tooley, Michael Kazim, Kyle J. Godfrey
A 66-year-old man was noted to have 2.5 mm of proptosis in the left eye. He had no additional orbital signs or evidence of cranial neuropathy. His visual acuity was 20/20 bilaterally. Computed tomography revealed a well-circumscribed, extraconal, inferolateral orbital mass that appeared to originate from the inferolateral zygoma, with areas of spiculated osseous densities partially surrounding the lesion (Figure 1A,B). Further characterization on magnetic resonance imaging revealed a heterogeneous mass without diffusion restriction or flow voids (Figure 1C,D). There was slowly increasing, stippled, heterogeneous contrast enhancement within the mass. The patient elected for an excisional biopsy. A swinging-eyelid orbitotomy was performed and the tumor was firmly adherent to the inferotemporal zygomatic bone at the area of the zygomaticofacial neurovascular bundle and inferior orbital fissure. The bone adjacent to the lesion was widely eroded, reflecting chronicity. The authors hypothesize that the bone encasement was acquired during growth and emergence through the inferior orbital fissure. The tumor was excised in total (Figure 1E). Histopathologic analysis was consistent with a cavernous venous malformation (Figure 1F). Post-operatively, his proptosis resolved and vision remained 20/20 without complications or evidence of recurrence at 8 months follow-up (Figure 2A,B).
The ROC Staging System for COVID-related Rhino-Orbital-Cerebral Mucormycosis
Published in Seminars in Ophthalmology, 2022
Milind N. Naik, Suryasnata Rath
Shah et al. reported a scoring system to define indications for exenteration. They used clinical symptoms, ophthalmic fundus findings, and imaging to score 15 patients.19 The authors categorized clinical signs such as ‘fixed eyeball’ (ophthalmoplegia) and ‘total blindness’ under ‘high score’. ROCM has a wide clinical spectrum, and patients can have ophthalmoplegia with preserved vision. The scoring system did not define how to score when such conflicting findings exist. Another set of 15 points were given to ophthalmic findings, some of which coincide with classic retinal findings expected in diabetics (cotton wool spots), while others simply indicated degree of proptosis (choroidal folds and congested retinal vessels). In radiology, any form of orbital involvement (globe, muscle, fat) was scored high, making exenteration a more likely choice. Moreover, intra-cranial spread was scored high, which in case of diffuse involvement, may not benefit with exenteration. Similarly, involvement of the superior orbital fissure and inferior orbital fissure both were scored high, which can be managed by IV antifungals and para-sinus dissection respectively rather than exenteration. Although this was the first attempt to form an objective scoring, it might skew the decision towards exenteration in cases that could have been managed by alternative means. Furthermore, there has been no validation of this scoring system.
Post-traumatic enophthalmos secondary to orbital fat atrophy: a volumetric analysis
Published in Orbit, 2020
Liza M. Cohen, Larissa A. Habib, Michael K. Yoon
CT images were exported in DICOM format and analyzed using OsiriX imaging software (v.9.0.2, Pixmeo, Switzerland). Total orbital volume and orbital fat volume for the fractured and normal contralateral orbits were measured via semiautomated segmentation with three-dimensional volume rendering assisted region-of-interest (ROI) computation in the axial plane (Figure 1). The “Closed Polygon” tool was used to manually create an ROI every three slices, encompassing all the orbital contents including prolapsed tissue for the total orbital volume measurements and only fat for orbital fat volume measurements. After the group of ROIs were selected, the “missing” ROIs were generated. These were checked for errors in segmentation, and corrections were made by manual adjustment using the “Repulsor” tool to adjust the borders of an ROI. Then, the volume of the ROI was computed. Bone window was used for total orbital volume measurements, and soft tissue window was used for orbital fat volume measurements. Intraconal and extraconal fat volumes were quantified separately by measuring volumes of ROIs for contiguous regions of fat and computing the sum. Approximation of the orbital septum was defined as the anterior orbital boundary. Posterior regions lacking a bony boundary (i.e. superior/inferior orbital fissures, orbital apex) were traced with a straight line. Enophthalmos was measured radiographically in relation to the lateral orbital rim and orbital apex, which has been shown to have a strong positive correlation with clinically measured enophthalmos using a Hertel exophthalmometer (r = 0.97).3