Graves ophthalmopathy, also known as thyroid eye disease (TED), is an autoimmune inflammatory disorder of the orbit and periorbital tissues, characterized by upper eyelid retraction, lid lag, swelling, redness (erythema), conjunctivitis, and bulging eyes (exophthalmos).[rx] It occurs most commonly in individuals with Graves’ disease,[rx] and less commonly in individuals with Hashimoto’s thyroiditis,[rx] or in those … [Read more…]

Cranial Nerve Six/Cranial nerve six (CN VI) also known as the abducens nerve, is one of the nerves responsible for the extraocular motor functions of the eye, along with the oculomotor nerve (CN III) and the trochlear nerve (CN IV). The sixth cranial nerve runs a long course from the brainstem to the lateral rectus muscle. Based on the location of … [Read more…]

The Occipital Nerves are a group of nerves that arise from the C2 and C3 spinal nerves. They innervate the posterior scalp up as far as the vertex and other structures as well, such as the ear.[rx] There are three major occipital nerves in the human body: the greater occipital nerve (GON), the lesser (or small) … [Read more…]

Third Cranial Nerve (CN III) /Oculomotor Nerve is the third cranial nerve (CN III). It enters the orbit via the superior orbital fissure and innervates extrinsic eye muscles that enable most movements of the eye and that raise the eyelid. The nerve also contains fibers that innervate the intrinsic eye muscles that enable pupillary constriction and accommodation (ability to focus on near objects as … [Read more…]

Oculomotor Nerve is the third cranial nerve (CN III). It enters the orbit via the superior orbital fissure and innervates extrinsic eye muscles that enable most movements of the eye and that raise the eyelid. The nerve also contains fibers that innervate the intrinsic eye muscles that enable pupillary constriction and accommodation (ability to focus on near objects as in reading). The oculomotor nerve … [Read more…]

The ophthalmic artery is the first branch of the internal carotid artery. It comes off just distal to the cavernous sinus. The ophthalmic artery gives off many branches, which supply the orbit, meninges, face, and upper nose. When the ophthalmic artery is occluded, it can compromise vision. The ophthalmic artery comes off the internal carotid … [Read more…]

The orbits are bony structures of the skull that house the globe, extraocular muscles, nerves, blood vessels, lacrimal apparatus, and adipose tissue. Each orbit protects the globe, while the supportive tissues allow the globe to move in three dimensions (horizontal, vertical, and torsional).[rx][rx] The anatomy of the orbit is a complex topic vital for understanding the communication … [Read more…]

The optic canal is a funnel-like structure as part of the sphenoid bone that extends from the optic foramen to the orbital apex, the posterior-most end of the orbit. The orbital apex consists of the optic canal and the superior orbital fissure. The superior orbital fissure is bordered superomedially by the lesser wing of the sphenoid bone … [Read more…]

Optic nerve sheath decompression more commonly known as optic nerve sheath fenestration (ONSF), is a surgical procedure performed to decompress the optic nerves and relieve vision-threatening papilledema in the setting of elevated intracranial pressure (ICP). Performance of this procedure is generally in cases of pseudotumor cerebri syndrome (PTC), where patients are rapidly losing vision from … [Read more…]

Optic Nerve Compression results in progressive, and often painless, vision loss. In features of anterior and posterior compressive optic neuropathy. We next review the common causes of compressive optic neuropathy, which include orbital tumors (e.g., optic nerve sheath meningioma, optic glioma, and capillary hemangioma), orbital infection, orbital inflammation, intracranial tumors (e.g., pituitary macroadenoma, meningioma, and … [Read more…]

Cysts of the optic nerve sheaths are exceptional, and the differential diagnosis with a slow evolutive tumor is very difficult. In the case of cysts of both optic nerves, with the progressive loss of vision that we are reporting, the possibility that its origin lies a coloboma of the optic disc is suggested by pathological … [Read more…]