Orbital apex anatomy pdf

It presents a critical relationship with the lateral sellar compartment, the pterygopalatine fossa and the middle cranial fossa. On the other hand, the transcranial approach generally is selected for orbital tumors with intracranial extension 7, 12, tumors located in the orbital apex or optic canal 3, 5, 7, and intracranial tumors with extension into the orbit 4, 12. Microsurgical anatomy of the superior orbital fissure. Lemke the clinician must have a detailed knowledge of orbital anatomy to understand the structural disarrangements in orbital disease and to employ appropriate medical and surgical procedures. In nontraumatic disorders, magnetic resonance imaging is the diagnostic modality of choice. This chapter discusses orbital anatomy with emphasis on those aspects that are important in. The anatomy of the orbital apex is significant for the complex association between bony, neural, and vascular elements. The optic nerve and ophthalmic artery pass through. Orbital apex figure 1a3 the apex of the orbit is the entry portal for all nerves and vessels to the eye and the site of origin of all extraocular muscles except the inferior oblique. Orbital anatomy and its clinical applications ento key.

The orbital apex refers to the posterior confluence of the orbit at the craniofacial junction, where nerves and vessels are transmitted from the intracranial compartment into the orbit via several bony apertures. The inferior orbital rim is formed by the maxillary bone medially and zygomatic bone laterally. Osseous anatomy of the orbital apex american journal of. Patients could present with signs and symptoms deriving from the involvement of structures within the orbital apex, the superior orbital fissure or the. Blowout fracture this refers to partial herniation of the orbital contents through one of its walls. At the apex of the orbital cavity lies the opening of the optic canal that runs at an angle of 45 degrees through the body of the.

Orbital apex syndrome is defined as the simultaneous dysfunction of the optic nerve and the cranial nerves manifesting with vision loss, ptosis, and a complete internal and external ophthalmoplegia as a result of a process occurring in the region of the optic canal and the superior orbital fissure orbital apex. Orbital anatomy study guide by picklesmd includes 292 questions covering vocabulary, terms and more. The slabs were reformatted from the orbital rim up to the orbital apex and evaluated at planes located 12 mm, 18 mm, and 24 mm from that interzygomatic line, defined as the line between the anterior margins of the frontal processes of zygomatic bones at the level of optic nerve plane. In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. A 61yearold man presented with retroorbital pain, nearcomplete ophthalmoplegia, loss of vision, and facial sensory deficits.

The origin of the inferior oblique muscle is here and represents the only extraocular muscle origin not at the orbital apex. These structures include the four rectus muscles taking their origin from the tendinous annulus of zinn, the optic nerve and ophthalmic artery through the. From an endoscopic viewpoint, only the medial aspect has a clinical significance. Where is the trochlear fossa located on the orbital bone. Applied anatomy tolosa hunt syndromeinflammation of the superior orbital fissure and apex may result in a multitude of signs including ophthalmoplegia and venous outflow obstruction superior orbital syndromefracture at superior orbital fissure involvement of cranial nerves diplopia, ophthalmoplegia, exophthalmos, ptosis 30. Orbitorbital cavity dimensions topographic relationships apertures soft tissues periorbital structures dimensions and topographic relationships dimensions 25 mm adult orbital dimensions volume 30 cc entrance height 35 mm entrance width 40 mm medial wall length 45 mm distance from posterior globe to optic 18 mm. Aug 22, 20 inflammation of the superior orbital fissure and apex tolosahunt syndrome may therefore result in a multitude of sign including ophthalmoplegia and venous outflow obstruction. Superior orbital fissure syndrome along with involvement of maxillary division of trigeminal nerve and optic nerve is known as orbital apex syndrome. The mri allows a good anatomic dissection of the orbital apex neurovascular. The bony orbit borders contents fractures teachmeanatomy.

Orbital anatomy and its clinical applications deborah d. Orbital apex syndrome, is a collection of cranial nerve deficits associated with a mass lesion near the apex of the orbit of the eye. Pdf endoscopic endonasal anatomy of superior orbital. Objective to study the outcome of patients with orbital apex lesions treated with endoscopic decompression alone. Zygomatic nerve the zygomatic nerve is a main branch of the maxillary division of the trigeminal nerve. Isolated sphenoid sinus mucocele presented as orbital apex syndrome maryam naser md and nafiseh hashemi md neuroophthalmology clinic, hashemi eye care, usa introduction a 62yearold male presented with horizontal diplopia to neuroophthalmology office on november 2018. Orbital apex syndrome oas involves cranial neuropathies in association with optic nerve dysfunction. Apex of orbit posterior most end of pyramid shaped orbit 4 orbital walls converge here at craniofacial junction complex association bw bony, neural, and vascular elements has 2 orifices situated in the sphenoid bone optic foramen superior orbital fissure. This article outlines the clinical presentation, neuroradiological approach, and the application of helpful ancillary investigations in the diagnosis of a range of cranial nerve syndromes. Traumatic orbital apex syndrome toas is a rare disease characterized by the damage of cranial nerves cns ii, iii, iv, and vi. The aim of our study was to analyze the functional recovery of cns in toas and discuss the management of these patients. The distinction is the precise anatomic involvement of the disease process. Orbital apex syndrome is symptomatically related to superior orbital fissure syndrome and cavernous sinus syndrome with similar etiologies.

Orbital apex syndrome an overview sciencedirect topics. An anatomical characteristic of the orbit is that structures are arranged in groups of seven. The superior orbital fissure and the orbital apex syndromes usually occur together. The orbital apex is the most posterior portion of the pyramidalshaped orbit, positioned at the craniofacial junction. The cavernous sinus syndrome affects iii, iv, v 1, v 2, vi and the sensory plexus of the ophthalmic artery. The orbital apex, formed by the superior orbital fissure and optic canal, is the cross. Functional recovery of cranial nerves in patients with. Evaluating osseous anatomy of the orbital apexwithcomputedtomographyctrequires knowledgeofitsthreedimensionalappearance. Syndromes of the orbital fissure, cavernous sinus, cerebello.

The orbital rim is more or less spiral with its two ends overlapping medially on either side of lacrimal fossa. At the apex of the orbital cavity lies the opening of the optic canal that runs at an angle of 45 degrees through the body of the sphenoid bone. Inflammation of the superior orbital fissure and apex tolosahunt syndrome may therefore result in a multitude of sign including ophthalmoplegia and venous outflow obstruction. We evaluated the ability of square area measurements of orbital apex crowding, calculated with mdct, to detect don. This syndrome is a separate entity from rochonduvigneaud syndrome, which occurs due to a lesion immediately anterior to the orbital apex. Setting departments of ophthalmology and otolaryngology, university of washington. Endoscopic endonasal anatomy of superior orbital fissure and. This usually occurs via blunt force trauma to the eye. The optic canal at the orbital apex connects the orbital cavity to the middle cranial fossa. The zygomatic bone forms the lateral orbital rim, while the frontal bone forms the superior orbital rim. Muscular crowding was calculated at each of these planes. Endoscopic endonasal anatomy of superior orbital fissure and orbital apex regions. Orbital apex syndrome oas denotes involvement of the optic nerve in addition to some or all of the cranial nerves within the cavernous sinussuperior orbital fissure iii, iv, v, vi.

A 61yearold man presented with retro orbital pain, nearcomplete ophthalmoplegia, loss of vision, and facial sensory deficits. Aug 21, 2015 applied anatomy tolosa hunt syndromeinflammation of the superior orbital fissure and apex may result in a multitude of signs including ophthalmoplegia and venous outflow obstruction superior orbital syndromefracture at superior orbital fissure involvement of cranial nerves diplopia, ophthalmoplegia, exophthalmos, ptosis 30. Pathological processes may extend intracranially via the superior orbital fissure and vice versa. It is also the point where the extraocular muscles derive their origins. Of course, proper selection of surgical approaches is very important, but it should be kept in.

Quizlet flashcards, activities and games help you improve your grades. Quantification of orbital apex crowding for screening of. Anatomy and physiology of the eye the orbital floor actually comprises bones. Their exposition should help in the development of new strategies by precisely defining the anatomy of structures in the orbital apex, the superior orbital fissure, and the oculomotor foramen. The anterior orbital rim has horizontal and vertical diameters of 4. These syndromes are characterised by combinations of cranial nerve lesions that occur because of the involvement of contiguous nerves that direct investigation to a specific site. A brief discussion of the ocular globe is also included. Orbital apex the orbital apex refers to the posterior confluence of the orbit at the craniofacial junction, where nerves and vessels are transmitted from the i. The volume of the orbital cavity in an adult is roughly about 30cc. Due to anatomical proximity, two other syndromes that can have overlapping features are the superior orbital fissure syndrome and the.

The superior orbital fissure lies between the body and the greater and lesser wings of the sphenoid bone. The orbital apex is an enclosed space containing several important neural and vascular structures, including the optic nerve, vascular supply to the eye and orbit. However, knowing this anatomy is crucial to evaluate complex fractures,tumors,andinflammatoryprocessesinvolvingtheorbitalapex. Clinical sciences radiology ecnr dubrovnik oct 2018. Orbital rim fracture this is a fracture of the bones forming the outer rim of the bony orbit.

Anatomy of orbit and clinical aspect of orbital disease. Not only can site of involvement guide the differential diagnostic considerations, but accurate descriptions of lesion location, involved structures, and extent of dissemination can facilitate proper treatment planning. P a t h o l o g y lesions of the optic nervesheath complex these lesions are located in the central portion of the ho kyu lee, et al. It usually occurs at the sutures joining the three bones of the orbital rim the maxilla, zygomatic and frontal. Dec 12, 2019 orbital apex syndrome is characterized by vision loss from optic neuropathy and ophthalmoplegia due to the involvement of ocular motor nerves in the anatomical region of the orbital apex. Orbit can refer to the bony socket, or it can also be used to imply the contents. Superior orbital fissure syndrome presents similarly to orbital apex syndrome without optic nerve. It transmits the optic nerve and ophthalmic artery, a branch of the internal carotid artery, which is the main arterial supply to the eye and orbital contents. From the medial orbital rim to apex, the orbit measures approximately 45 mm in length, whereas from the lateral orbital rim to the apex, the measurement is approximately 1 cm shorter. The thin orbital floor is susceptible to blunt trauma, often causing a blowout fracture. A basic understanding of orbital anatomy is critical in evaluation of orbital neoplasms.

This syndrome is a separate entity from rochonduvigneaud syndrome, which occurs due to a lesion immediately anterior to the. In superior orbital fissure syndrome, there is progressive paralysis of abducent, oculomotor and trochlear nerves. It is also the point where the extraocular muscles derive their origins contents. The superior orbital fissure is a critical threedimensional space connecting the middle cranial fossa and the orbit. In the adult human, the volume of the orbit is 30 millilitres 1. Tao clinical anatomy the orbit is conical and has a volume of about 30 cm3. Any information contained in this pdf file is automatically generated from digital. Nov 21, 2012 the superior orbital fissure is a critical threedimensional space connecting the middle cranial fossa and the orbit. It curves downwards and medially widening at the orbital apex containing the superior ophthalmic vein, ophthalmic division of the trigeminal nerve and branches lacrimal, frontal, supraorbital, supratrochlear and nasocillary, and the nerves to the extra ocular muscles table 2. Diseases of the orbital apex and cavernous sinus usually present with involvement of multiple cranial nerves, corresponding to the complex anatomy of the region. Jun 21, 2016 orbital anatomy swapna vemuri and jeremiah p. Morphologically, each orbit is a four sided pyramid with a posterior apex and anterior base.

The orbits are pyramidal structures separating the upper and middle facial skeletons. Fractures of the apex rarely are isolated because they occur in the association with or as extension of fractures of the facial skeleton, base of skull. In the orbit, all openings are arranged around the base, apex or between the orbital walls. The inferior orbital fissure lies between the greater wing of sphenoid bone and maxilla, connecting the orbit to the pterygopalatine and infratemporal fossae. Orbital apex syndrome is characterized by vision loss from optic neuropathy and ophthalmoplegia due to the involvement of ocular motor nerves in the anatomical region of the orbital apex. May 20, 2016 the orbital apex is the most posterior portion of the pyramidalshaped orbit, positioned at the craniofacial junction. Clinical anatomy of the superior orbital fissure and the. He recently had a cold and was having mucus discharge on the left eye and. Endoscopic endonasal anatomy of superior orbital fissure. Evaluating osseous anatomy of the orbital apex with computed tomography ct requires knowledge of its threedimensional appearance. Isolated sphenoid sinus mucocele presented as orbital apex. The connective tissue layers and neural and vascular structures of. The orbits are paired structures, located on the anterior part of the face. The orbital apex syndrome affects the cranial nerves.

Don, a serious complication of go, is frequently difficult to diagnose clinically in its early stages because of confounding signs and symptoms of congestive orbitopathy. The orbital apex is the narrowest area of the orbit, and the optic nerve lies in close proximity to the medial and superior recti in the area of annulus of zinn. Schematic drawing of coronal anatomy of the orbital apex. Even with magnification and microtechniques, it is extremely difficult to deal with infiltrating pathology meningiomas or tumors crowding the region. There are three bony apertures that permit the entry of neurovasculature in to the orbit. The type of fracture was identified, and the presence of optic nerve damage, the superior orbital fissure syndrome, or the orbital apex syndrome was noted. The walls, apex, and base harbor several foramina and fissures as well as bony irregularities where various ligaments, muscles, and capsules attach. A comprehensive knowlege of orbital and peri orbital anatomy is necessary to understand the various disorders of this region and in its surgical mangement. However, its capabilities can be fully used only with thorough knowledge of the complicated topographic relationships in this region.

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