[Music] hi this is Peter from Anatomy Zone and in this tutorial we will be taking a look at the anatomy of the Bony orbit this video is a collaboration between Anatomy Zone and teachmeanatomy doino check out the links in the video description below for some useful articles to accompany this video tutorial the Bony orbits or eye sockets are bilateral and symmetrical cavities in the head they enclose the eyeball and its Associated structures the orbit can be thought of as a pyramidal structure with the Apex pointing posterior medially into the optic Fen and the base situated anteriorly opening up into the face and formed by the orbital Rim the boundaries of the orbit are formed by seven Bones from this anterior view you can see the frontal bone in red the maxillar in purple the zygomatic bone in light blue the sphenoid bone posteriorly in yellow and the ethoid bone in orange looking here at the medial aspect of the orbit you can see a better view of the lacal bone in green the ethmoid bone in Orange and a small part of the Palatine bone in dark blue let's take a look at the base of this pyramid and the boundaries of the orbital Rim starting superiorly you can see this border formed by the frontal bone the medial border is formed by the frontal process of the maxilla the inferior border is formed by the zygomatic process of the mailla and the zygomatic bone the lateral border is formed by the front Al process of the zygomatic bone and the zygomatic process of the frontal bone now let's take a look at the other components of the Bony orbit the roof or the superior wall is formed by the frontal bone and the Lesser wing of the sphenoid the frontal bone separates the orbit from the anterior cranial fosser I've just switched to A View to demonstrate the sphenoid bone which can be a confusing bone to understand from this anterior view you can see the Lesser Wing the greater wing and the superior orbital fissure and to illustrate this from within the cranium I've rotated around to show these structures from a posterior and internal view the floor or inferior wall is formed by the Magilla the Palatine and zygomatic Bones the Magilla separates the orbit from the underlying maxillary sinus the medial wall is formed by the ethmoid the maxilla the lacal and sphenoid Bones the ethmoid bone separates the orbit from the ethmoid sinus the lateral wall is formed by the zygomatic bone and the greater wing of the sphenoid the apex of the orbit is located at the opening to the optic Canal which is known as the optic framan the face as we have seen opens out into the face and is bounded by the eyelids it is also known as the orbital Rim let's take a quick look now at the contents of the Bony orbit the Bony orbit contains the eyeballs and their Associated structures these include the extraocular muscles the eyelids and several nerves and blood vessels the extraocular muscles are responsible for the movement of the eyeball and the superior eyelid we'll take a look at the extraocular muscles in the next tutorial in terms of the nerves within the Bony orbit there are several cranial nerves which Supply the eye and its structures these include the optic the ocular motor the troa the trigeminal and the abducens nerve there are also several blood vessels within the Bony orbit the eye receives blood primarily from the Opthalmic artery Venus drainage is VI the superior and inferior Opthalmic veins let's take a look now at the pathways into the orbit there are three main Pathways by which structures can enter and exit the orbit these include the optic Canal the superior orbital fissure and the inferior orbital fissure the optic Canal transmits the optic nerve and the Opthalmic artery it opens into the middle cranial the superior orbital fure lies laterally to the optic canal and transmits several nerves including the lacal the frontal the fourth cranial nerve which is the tra the superior and inferior branches of the ocular motor nerve which is cranial nerve 3 the nasos branches of the Opthalmic nerve which is the first branch of the trigeminal nerve cranial nerve 5 and it also transmits the abducens nerve cranial nerve number six in addition it also carries the superior Opthalmic vein the inferior orbital fure separates the lateral wall of the orbit from the floor of the orbit this fissure transmits the zygomatic branch of the maxillary nerve which is the second branch of the trigeminal nerve cranial nerve 5 as well as the maxillary nerve itself in addition it transmits the inferior Opthalmic vein and also some sympathetic nerves there are also o some other minor openings into the orbital cavity the nasolacrimal canal which drains tears from the eye to the nasal cavity is located on the medial wall of the orbit other small openings include the Supra orbital framan and the infraorbital Fen which transmits small neurovascular structures the infraorbital Groove begins posteriorly at the inferior orbital fissure and passes across the floor of the orbit to connect with the infraorbital Canal which then opens up onto the face via the infraorbital framen so that's the anatomy of the Bony orbit for more Anatomy articles check out teachmeanatomy doino and for more Anatomy videos and flashcards check out Anatomy zone.com if you have found this video useful click on the like button below and subscribe to Anatomy zone for more video tutorials thank you for watching the 3D models uced in this tutorial were powered by the excellent and free Anatomy learning app check it out for yourself